Organization, Consolidation and Presentation of Financial Statements [Abstract] Number of regional operating segments Number of Operating Segments Goodwill and Intangible Assets Disclosure [Abstract] Schedule of Goodwill [Table] Schedule of Goodwill [Table] Segments [Axis] Segments [Axis] Segments [Domain] Segments [Domain] Eastern Eastern Region [Member] Eastern region. Western Western Region [Member] Western region. Recycling Recycling [Member] Recycling [Member] Other Other Segments [Member] Goodwill [Line Items] Goodwill [Line Items] Goodwill [Roll Forward] Goodwill [Roll Forward] Goodwill, beginning balance Goodwill Acquisitions Goodwill, Acquired During Period Goodwill, ending balance Statement of Comprehensive Income [Abstract] Net loss Net Income (Loss) Attributable to Parent Other comprehensive (loss) income, before tax: Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract] Hedging activity: Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, before Tax [Abstract] Interest rate swap settlements Other Comprehensive Income (Loss), Derivative, Excluded Component, Increase (Decrease), Adjustments, before Tax Interest rate swap amounts reclassified into interest expense Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax Unrealized (loss) gain resulting from changes in fair value of derivative instruments Other Comprehensive Income (Loss), Financial Liability, Fair Value Option, Unrealized Gain (Loss) Arising During Period, before Tax Other comprehensive (loss) income Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent Income tax (benefit) provision related to items of other comprehensive (loss) income Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent Other comprehensive (loss) income, net of tax Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Comprehensive income (loss) Comprehensive Income (Loss), Net of Tax, Attributable to Parent Environmental Remediation Obligations [Abstract] Environmental Exit Costs by Cost Environmental Exit Costs by Cost [Table Text Block] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Covenants Not-to-Compete Noncompete Agreements [Member] Client Lists Customer Lists [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Intangible assets Finite-Lived Intangible Assets, Gross Less accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Intangible assets, net Finite-Lived Intangible Assets, Net Equity [Abstract] Summary of Stock Option Activity Share-based Payment Arrangement, Option, Activity [Table Text Block] Summary of Restricted Stock, Restricted Stock Unit and Performance-based Stock Unit Activity Share-based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block] Summary of Changes in Balances of Each Component of Accumulated Other Comprehensive Loss Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Summary of Reclassifications Out of Accumulated Other Comprehensive Loss Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Earnings Per Share [Abstract] EARNINGS PER SHARE Earnings Per Share [Text Block] Leases [Abstract] Schedule of Lease Costs and Other Lease Information Lease, Cost [Table Text Block] Schedule of estimated minimum future finance lease obligations Finance Lease, Liability, Maturity [Table Text Block] Schedule of estimated minimum future operating lease obligations Lessee, Operating Lease, Liability, Maturity [Table Text Block] Asset Retirement Obligation Disclosure [Abstract] Summary of Changes to Accrued Capping, Closure and Post-Closure Liabilities Schedule of Change in Asset Retirement Obligation [Table Text Block] Debt And Derivatives Disclosure [Abstract] Debt And Derivatives Disclosure [Abstract] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Hedging Relationship [Axis] Hedging Relationship [Axis] Hedging Relationship [Domain] Hedging Relationship [Domain] Cash Flow Hedging Cash Flow Hedging [Member] Derivative Instrument [Axis] Derivative Instrument [Axis] Derivative Contract [Domain] Derivative Contract [Domain] Interest Rate Derivative Interest Rate Contract [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Interest rate derivatives entered into Number of Interest Rate Derivatives Held Notional amount Derivative, Notional Amount Weighted average percentage rate paid Derivative, Average Fixed Interest Rate Fair Value Disclosures [Abstract] Measurement Basis [Axis] Measurement Basis [Axis] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Fair Value Estimate of Fair Value Measurement [Member] Carrying Value Reported Value Measurement [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Term Loan B Facility due October 2023; bore interest at LIBOR plus 2.50% Term Facility due October 2023 (Term Loan B Facility) [Member] Term Facility due October 2023 (Term Loan B Facility) [Member] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Fixed Rate Bonds Fixed Rate Bonds [Member] Fixed rate bonds. Secured Debt Secured Debt [Member] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Significant Other Observable Inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Fair value of fixed rate debt Debt Instrument, Fair Value Disclosure Carrying value of revolver debt Lines of Credit, Fair Value Disclosure Loss on debt extinguishment Gain (Loss) on Extinguishment of Debt FAIR VALUE OF FINANCIAL INSTRUMENTS Fair Value Disclosures [Text Block] Derivative Instruments, Gain (Loss) [Table] Derivative Instruments, Gain (Loss) [Table] Hedging Designation [Axis] Hedging Designation [Axis] Hedging Designation [Domain] Hedging Designation [Domain] Designated as Hedging Instrument Designated as Hedging Instrument [Member] Interest rate swaps Interest Rate Swap [Member] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Interest expense Interest Expense [Member] Derivative Instruments, Gain (Loss) [Line Items] Derivative Instruments, Gain (Loss) [Line Items] Other comprehensive loss, reclassification adjustment from AOCI GOODWILL AND INTANGIBLE ASSETS Intangible Assets Disclosure [Text Block] Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Measurement Frequency [Domain] Measurement Frequency [Domain] Fair Value, Measurements, Recurring Fair Value, Recurring [Member] Quoted Prices in Active Markets for Identical Assets (Level 1) Fair Value, Inputs, Level 1 [Member] Significant Unobservable Inputs (Level 3) Fair Value, Inputs, Level 3 [Member] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Restricted investment securities - landfill closure Landfill [Member] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Assets: Assets [Abstract] Restricted investment securities - landfill closure Restricted Cash and Investments, Noncurrent Interest rate swaps Derivative Asset Total Assets, Fair Value Disclosure Liabilities: Liabilities [Abstract] Interest rate swaps Interest Rate Derivative Liabilities, at Fair Value Revenue from Contract with Customer [Abstract] Revenue, Initial Application Period Cumulative Effect Transition [Table] Revenue, Initial Application Period Cumulative Effect Transition [Table] Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition [Domain] Initial Application Period Cumulative Effect Transition [Domain] Adjustments Difference between Revenue Guidance in Effect before and after Topic 606 [Member] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Accounting Standards Update 2014-09 Accounting Standards Update 2014-09 [Member] Revenue, Initial Application Period Cumulative Effect Transition [Line Items] Revenue, Initial Application Period Cumulative Effect Transition [Line Items] Revenues Revenues Revenue recognized Contract with Customer, Performance Obligation Satisfied in Previous Period Gross receivables from contracts Contract with Customer, Asset, Gross, Current Contract liabilities Contract with Customer, Liability, Current Acquisition activities Expense From Acquisition And Financing Costs And Other Items, Acquisition Activities Acquisition And Financing Costs And Other Items, Acquisition Activities Write-off Of deferred costs Expense From Acquisition And Financing Costs And Other Items, Write-Off Of Deferred Costs Expense From Acquisition And Financing Costs And Other Items, Write-Off Of Deferred Costs Site Contingency [Table] Site Contingency [Table] Environmental Remediation Site [Axis] Environmental Remediation Site [Axis] Environmental Remediation Site [Domain] Environmental Remediation Site [Domain] Southbridge Landfill Southbridge Landfill [Member] Southbridge landfill. Site Contingency [Line Items] Site Contingency [Line Items] Charlton settlement charge Loss Contingency, Loss in Period Legal settlement Legal Fees Southbridge Landfill closure charge, net Landfill Closure (Settlement) Charge, Net The aggregate (recovery) charge associated with the closure of a landfill, which is comprised of an asset impairment charge, a development project charge write-off, an environmental remediation charge, a legal settlement charge, related legal and transaction costs and a recovery on insurance settlement. A positive number is an expense and a negative number is a gain. Contract settlement charge Contract Settlement Charge Amount of loss recognized in the period associated with the settlement of a future obligation associated with the termination of a contract. Project development charge Noncash Project Abandonment Costs Accounting Changes and Error Corrections [Abstract] Basis of Accounting Basis of Accounting, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Subsequent Events Subsequent Events, Policy [Policy Text Block] Accounting Standards that are Adopted and Pending Adoption New Accounting Pronouncements, Policy [Policy Text Block] Revenue Recognition Revenue [Policy Text Block] Leases Lessee, Leases [Policy Text Block] Accrued Final Capping, Closure and Post Closure Asset Retirement Obligation [Policy Text Block] Commitments and Contingencies Commitments and Contingencies, Policy [Policy Text Block] Fair Value of Financial Instruments Fair Value of Financial Instruments, Policy [Policy Text Block] Segment Reporting Segment Reporting, Policy [Policy Text Block] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Class A Common Stock Common Class A [Member] Class B Common Stock Common Class B [Member] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Numerator: Net Income (Loss) Available to Common Stockholders, Diluted [Abstract] Net income (loss) Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent Number of shares outstanding, end of period: Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Common stock, outstanding shares (in shares) Common Stock, Shares, Outstanding Shares to be issued - acquisition (in shares) Weighted Average Number of Shares, Contingently Issuable Unvested restricted stock (in shares) Weighted Average Number of Shares, Restricted Stock Effect of weighted average shares outstanding (in shares) Weighted Average Number of Shares Issued, Basic Basic weighted average common share outstanding (in shares) Weighted Average Number of Shares Outstanding, Basic Impact of potentially dilutive securities: Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract] Dilutive effect of stock options and other stock awards (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Diluted weighted average shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Diluted Antidilutive potentially issuable shares (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount LONG-TERM DEBT Debt and Capital Leases Disclosures [Text Block] Segment Reporting [Abstract] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Operating Segments Operating Segments [Member] Eliminations Consolidation, Eliminations [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Revenues Depreciation and amortization Depreciation, Depletion and Amortization Operating income (loss) Operating Income (Loss) Total assets Assets Commitments and Contingencies Disclosure [Abstract] Summary of Environmental Liability Associated with Potsdam Schedule of Environmental Loss Contingencies by Site [Table Text Block] Accrual for Environmental Loss Contingencies [Roll Forward] Accrual for Environmental Loss Contingencies [Roll Forward] Beginning balance Accrual for Environmental Loss Contingencies Accretion expense Accrual for Environmental Loss Contingencies, Charges to Expense for New Losses Obligations settled Accrual for Environmental Loss Contingencies, Payments Ending balance COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Business Combinations [Abstract] Revenues Business Acquisition, Pro Forma Revenue Operating income Business Acquisitions Pro Forma Operating Income Loss The pro forma operating income for the period as if the business combination or combinations had been completed at the beginning of the period. Net income (loss) Business Acquisition, Pro Forma Net Income (Loss) Basic earnings per common share attributable to common stockholders (in dollars per share) Business Acquisition, Pro Forma Earnings Per Share, Basic Diluted earnings per share attributable to common stockholders (in dollars per share) Business Acquisition, Pro Forma Earnings Per Share, Diluted OTHER ITEMS AND CHARGES Unusual or Infrequent Items, or Both, Disclosure [Text Block] Income Tax Disclosure [Abstract] INCOME TAXES Income Tax Disclosure [Text Block] Summary of Numerator and Denominators Used in Computation of Earnings Per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Statement of Stockholders' Equity [Abstract] Statement [Table] Statement [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock Common Stock [Member] Additional Paid-In Capital Additional Paid-in Capital [Member] Accumulated Deficit Retained Earnings [Member] Accumulated Other Comprehensive Loss AOCI Attributable to Parent [Member] Statement [Line Items] Statement [Line Items] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning balance Stockholders' Equity Attributable to Parent Beginning balance (in shares) Issuance of Class A common stock - equity offering Stock Issued During Period, Value, New Issues Issuance of Class A common stock - equity offering (in shares) Stock Issued During Period, Shares, New Issues Issuance of Class A common stock - acquisition Stock Issued During Period, Value, Acquisitions Issuance of Class A common stock - acquisition (in shares) Stock Issued During Period, Shares, Acquisitions Issuances of Class A common stock Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture Issuances of Class A common stock (in shares) Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture Stock-based compensation APIC, Share-based Payment Arrangement, Increase for Cost Recognition Net income (loss) Hedging activity Cumulative effect of new accounting principle Cumulative Effect of New Accounting Principle in Period of Adoption Ending balance Ending balance (in shares) Schedule of Limited Partners' Capital Account by Class [Table] Schedule of Limited Partners' Capital Account by Class [Table] Sale of Stock [Axis] Sale of Stock [Axis] Sale of Stock [Domain] Sale of Stock [Domain] Public Stock Offering Public Stock Offering [Member] Public Stock Offering [Member] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] 2016 Plan 2016 Incentive Plan [Member] 2016 Incentive Plan 2006 Incentive Plan Two Thousand Six Stock Incentive Plan [Member] Two thousand six stock incentive plan. Amended and Restated 1997 Employee Stock Purchase Plan Amended And Restated Nineteen Ninety Seven Employee Stock Purchase Plan [Member] Amended And Restated Nineteen Ninety Seven Employee Stock Purchase Plan [Member] Statistical Measurement [Axis] Statistical Measurement [Axis] Statistical Measurement [Domain] Statistical Measurement [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Weighted Average Weighted Average [Member] Award Type [Axis] Award Type [Axis] Award Type [Domain] Award Type [Domain] Stock Options Share-based Payment Arrangement, Option [Member] Restricted Stock, Restricted Stock Units, and Performance-Based Stock Units Restricted Stock Restricted Stock Units And Performance Stock Units [Member] Restricted stock, restricted stock units and performance stock units. Restricted Stock Awards Restricted Stock Awards [Member] Restricted Stock Awards [Member] Restricted Stock and Restricted Stock Unit Restricted Stock And Restricted Stock Unit [Member] Restricted stock and restricted stock unit. Performance-Based Stock Units Performance Stock Unit [Member] Performance stock unit. Title of Individual [Axis] Title of Individual [Axis] Title of Individual [Domain] Title of Individual [Domain] Non-Employee Director Non Employee Director [Member] Non Employee Director [Member] Limited Partners' Capital Account [Line Items] Limited Partners' Capital Account [Line Items] Sale of stock, number of shares issued (in shares) Sale of Stock, Number of Shares Issued in Transaction Sale of stock, price per share (in dollars per share) Sale of Stock, Price Per Share Sale of stock, net proceeds Sale of Stock, Consideration Received on Transaction Common stock, authorized shares (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Common stock, additional authorized shares (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Number of shares available for future grant (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Options granted period Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period Options vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Stock-based compensation expense Share-based Payment Arrangement, Expense Aggregate intrinsic value of options exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Total fair value of other stock awards vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Unrecognized stock-based compensation expense Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount Unrecognized stock-based compensation expense, weighted average period Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Stock Options Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Beginning balance, outstanding (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Ending balance, outstanding (in shares) Exercisable at end of period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Beginning balance, outstanding (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Granted (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Exercised (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Forfeited (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Ending balance, outstanding (in dollars per share) Exercisable at end of period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Weighted Average Remaining Contractual Term (years) and Aggregate Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Weighted Average Remaining Contractual Term, Outstanding Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Weighted Average Remaining Contractual Term, Exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Aggregate Intrinsic Value, Outstanding at end of period Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Aggregate Intrinsic Value, Exercisable at end of period Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Interest Rate Swaps Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] Other comprehensive income before reclassifications Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Amounts reclassified from accumulated other comprehensive income Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax Income tax benefit (provision) related to items of other comprehensive loss Other Comprehensive Income (Loss), Tax Other comprehensive income (loss), net of tax Other Comprehensive Income (Loss), Net of Tax Reclassification out of Accumulated Other Comprehensive Income [Table] Reclassification out of Accumulated Other Comprehensive Income [Table] Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] Amounts Reclassified Out of Accumulated Other Comprehensive Income Reclassification out of Accumulated Other Comprehensive Income [Member] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Interest expense Interest Expense Income (loss) before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest (Benefit) provision for income taxes Income Tax Expense (Benefit) Statement of Cash Flows [Abstract] Landfill Cash Flows from Operating Activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Net income (loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Adjustments to reconcile net income (loss) to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Operating lease right-of-use assets expense Operating Lease, Expense Depletion of landfill operating lease obligations Depletion Of Landfill Operating Lease Obligations This element represents the noncash expense charged against earnings to recognize the depletion of landfill operating lease obligations. Interest accretion on landfill and environmental remediation liabilities Accretion Expense, Including Asset Retirement Obligations Amortization of debt issuance costs and discount on long-term debt Amortization of Debt Issuance Costs and Discounts Stock-based compensation Share-based Payment Arrangement, Noncash Expense Gain on sale of property and equipment Gain (Loss) on Disposition of Property Plant Equipment Southbridge Landfill non-cash closure charge Noncash Landfill Closure Charge The non-cash portion of the aggregate charge associated with the closure of a landfill, which includes a non-cash asset impairment charge, a non-cash project development charge, a reserve for a legal settlement and a non-cash environmental remediation charge. Development project charge Non-cash expense from acquisition activities and other items Non-Cash Expense From Acquisition Activities and Other Items The aggregate amount of noncash expense associated with acquisition activities and other items recognized during the accounting period that are not disclosed separately. Generally, these items are either unusual or infrequent, but not both. Loss on debt extinguishment Deferred income taxes Deferred Income Tax Expense (Benefit) Changes in assets and liabilities, net of effects of acquisitions and divestitures: Increase (Decrease) in Operating Capital [Abstract] Accounts receivable Increase (Decrease) in Accounts Receivable Accounts payable Increase (Decrease) in Accounts Payable Prepaid expenses, inventories and other assets Increase (Decrease) in Prepaid Expense and Other Assets Accrued expenses, contract liabilities and other liabilities Increase (Decrease) in Accrued Liabilities Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Cash Flows from Investing Activities: Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Acquisitions, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Additions to property, plant and equipment Payments to Acquire Property, Plant, and Equipment Payments on landfill operating lease contracts Payments For Landfill Operating Lease The cash outflow associated with landfill operating agreements consisting of up-front or one-time payments, future minimum rental payments, including success/expansion fees, other direct costs and capping, closure and post closure costs. Proceeds from sale of property and equipment Proceeds from Sale of Property, Plant, and Equipment Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Cash Flows from Financing Activities: Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Proceeds from long-term borrowings Proceeds from Issuance of Long-term Debt and Capital Securities, Net Principal payments on long-term debt Repayment of Long-term Debt, Long-term Lease Obligation, and Capital Security Payments of debt issuance costs Payments of Debt Issuance Costs Proceeds from the exercise of share based awards Proceeds, Issuance of Shares, Share-based Payment Arrangement, Including Option Exercised Proceeds from the issuance of Class A Common Stock Proceeds from Issuance of Common Stock Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities Net (decrease) increase in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents, beginning of period Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents, end of period Cash paid during the period for: Supplemental Cash Flow Information [Abstract] Interest Interest Paid, Excluding Capitalized Interest, Operating Activities Income taxes, net of refunds Income Taxes Paid, Net Supplemental Disclosure of Non-Cash Investing and Financing Activities: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Non-current assets obtained through long-term obligations Fair Value of Assets Acquired Revolving line of credit facility (Revolving Credit Facility) due May 2023; bearing interest at LIBOR plus 1.75% Revolving Credit Facility Due May Two Thousand Twenty Three [Member] Revolving Credit Facility Due May Two Thousand Twenty Three [Member] New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014 (New York Bonds 2014) due December 2044 - fixed rate interest period through 2019; bearing interest at 3.75% Revenue Bonds Series Two Thousand Fourteen Due Two Thousand Forty Four [Member] Revenue Bonds Series Two Thousand Fourteen Due Two Thousand Forty Four [Member] New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014R-2 (New York Bonds 2014R-2) due December 2044 - fixed rate interest period through 2026; bearing interest at 3.125% Revenue Bond Series Two Thousand Fourteen R Two Due Two Thousand Forty Four [Member] Revenue Bond Series Two Thousand Fourteen R Two Due Two Thousand Forty Four [Member] Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-3 (FAME Bonds 2005R-3) due January 2025 - fixed rate interest period through 2025; bearing interest at 5.25% Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-3 (FAME Bonds 2005R-3) [Member] Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-3 (FAME Bonds 2005R-3) [Member] Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2015R-1 (FAME Bonds 2015R-1) due August 2035 - fixed rate interest period through 2025; bearing interest at 5.125% Finance Authority Of Maine Solid Waste Disposal Revenue Bonds Series 2015R-1 [Member] Finance Authority Of Maine Solid Waste Disposal Revenue Bonds Series 2015R-1 [Member] Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2015R-2 (FAME Bonds 2015R-2) due August 2035 - fixed rate interest period through 2025; bearing interest at 4.375% Finance Authority Of Maine Solid Waste Disposal Revenue Bonds Series 2015R-2 [Member] Finance Authority Of Maine Solid Waste Disposal Revenue Bonds Series 2015R-2 [Member] Vermont Economic Development Authority Solid Waste Disposal Long-Term Revenue Bonds Series 2013 (Vermont Bonds) due April 2036 - fixed rate interest period through 2028; bearing interest at 4.625% Long Term Revenue Bond Series Two Thousand Thirteen Due Two Thousand Thirty Six [Member] Long Term Revenue Bond Series Two Thousand Thirteen Due Two Thousand Thirty Six [Member] Business Finance Authority of the State of New Hampshire Solid Waste Disposal Revenue Bonds Series 2013 (New Hampshire Bonds) due April 2029 - fixed rate interest period through 2019; bearing interest at 4.00% Revenue Bond Series Two Thousand Thirteen Due Two Thousand Twenty Nine [Member] Revenue Bond Series Two Thousand Thirteen Due Two Thousand Twenty Nine [Member] Finance leases maturing through December 2107; bearing interest at a weighted average of 5.2% Capital Lease Obligations [Member] Notes payable maturing through June 2027; bearing interest at a weighted average of 3.4% Notes Payable [Member] Notes Payable [Member] Revolving Credit Facility and Term Loan Facility (collectively, the Credit Facility) Credit Facility [Member] Credit Facility [Member] Term loan A facility (Term Loan Facility) due May 2023; bearing interest at LIBOR plus 1.75% Term Facility Due May 2023 (Term Loan B Facility) [Member] Term Facility Due May 2023 (Term Loan B Facility) [Member] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] LIBOR London Interbank Offered Rate (LIBOR) [Member] Long-term debt and capital lease Debt and Lease Obligation Finance leases maturing through December 2107; bearing interest at a weighted average of 5.2% Finance Lease, Liability Less—unamortized discount and debt issuance costs Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net Long-term debt and finance leases less unamortized discount and debt issuance costs Long-term Debt and Lease Obligation, Including Current Maturities Less—current maturities of long-term debt and finance leases Long-term Debt and Lease Obligation, Current Non current portion of long term debt and capital lease obligation Long-term Debt and Lease Obligation Basis spread on variable rate Debt Instrument, Basis Spread on Variable Rate Stated interest rate Debt Instrument, Interest Rate, Stated Percentage Weighted-average interest rate - finance leases Finance Lease, Weighted Average Discount Rate, Percent Weighted average interest rate Debt, Weighted Average Interest Rate Summary of Financial Information by Reportable Segment Schedule of Segment Reporting Information, by Segment [Table Text Block] Summary of Revenues Attributable to Services Provided by Company Revenue from External Customers by Products and Services [Table Text Block] Revenue from External Customers by Products and Services [Table] Revenue from External Customers by Products and Services [Table] Product and Service [Axis] Product and Service [Axis] Product and Service [Domain] Product and Service [Domain] Collection Solid Waste Operations Collection [Member] Solid Waste Operations Collection [Member] Disposal Solid Waste Operations Disposal [Member] Solid Waste Operations Disposal [Member] Power generation Solid Waste Operations Power Generation [Member] Solid Waste Operations Power Generation [Member] Processing Solid Waste Operations Processing [Member] Solid Waste Operations Processing [Member] Solid waste operations Solid Waste Operations [Member] Solid waste operations. Organics Organics [Member] Organics. Customer solutions Customer Solutions [Member] Customer solutions. Revenue from External Customer [Line Items] Revenue from External Customer [Line Items] Potsdam Environmental Remediation Liability Potsdam Environmental Liability [Member] Potsdam environmental liability. Obligations settled Summary of Goodwill Activity Schedule of Goodwill [Table Text Block] Summary of Intangible Assets by Intangible Asset Type Schedule of Finite-Lived Intangible Assets [Table Text Block] Summary of Intangible Amortization Expense Estimated Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] REVENUE RECOGNITION Revenue from Contract with Customer [Text Block] BASIS OF PRESENTATION Business Description and Basis of Presentation [Text Block] Operating Leases Lessee, Operating Lease, Liability, Payment, Due [Abstract] Fiscal year ending December 31, 2019 Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year Fiscal year ending December 31, 2020 Lessee, Operating Lease, Liability, Payments, Due Year Two Fiscal year ending December 31, 2021 Lessee, Operating Lease, Liability, Payments, Due Year Three Fiscal year ending December 31, 2022 Lessee, Operating Lease, Liability, Payments, Due Year Four Fiscal year ending December 31, 2023 Lessee, Operating Lease, Liability, Payments, Due Year Five Thereafter Lessee, Operating Lease, Liability, Payments, Due after Year Five Total lease payments Lessee, Operating Lease, Liability, Payments, Due Less: interest expense Lessee, Operating Lease, Liability, Undiscounted Excess Amount Lease liability balance Operating Lease, Liability Finance Leases Finance Lease, Liability, Payment, Due [Abstract] Fiscal year ending December 31, 2019 Finance Lease, Liability, Payments, Remainder of Fiscal Year Fiscal year ending December 31, 2020 Finance Lease, Liability, Payments, Due Year Two Fiscal year ending December 31, 2021 Finance Lease, Liability, Payments, Due Year Three Fiscal year ending December 31, 2022 Finance Lease, Liability, Payments, Due Year Four Fiscal year ending December 31, 2023 Finance Lease, Liability, Payments, Due Year Five Thereafter Finance Lease, Liability, Payments, Due after Year Five Total lease payments Finance Lease, Liability, Payment, Due Less: interest expense Finance Lease, Liability, Undiscounted Excess Amount Lease liability balance Income Statement [Abstract] Operating expenses: Costs and Expenses [Abstract] Cost of operations Cost of Goods and Services Sold General and administration General and Administrative Expense Expense from acquisition activities and other items Expense From Acquisition And Financing Costs And Other Items The aggregate amount of expense associated with acquisition activities and other items recognized during the accounting period that are not disclosed separately. Generally, these items are either unusual or infrequent, but not both. Southbridge Landfill closure charge, net Total operating expenses Costs and Expenses Operating income Other expense (income): Nonoperating Income (Expense) [Abstract] Interest income Interest Income, Other Other income Other Nonoperating Income Other expense, net Nonoperating Income (Expense) Income (loss) before income taxes Net income (loss) Basic earnings per share attributable to common stockholders: Earnings Per Share, Basic [Abstract] Weighted average common shares outstanding (in shares) Basic earnings per common shares (in dollars per share) Earnings Per Share, Basic Diluted earnings per share attributable to common stockholders: Earnings Per Share, Diluted [Abstract] Weighted average common shares outstanding (in shares) Diluted earnings per common share (in dollars per share) Earnings Per Share, Diluted ACCRUED FINAL CAPPING, CLOSURE AND POST CLOSURE Asset Retirement Obligation Disclosure [Text Block] Schedule of New Accounting Pronouncements and Changes in Accounting Principles Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block] Intangible amortization expenses Amortization of Intangible Assets Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Tuck-in Solid Waste Collection Tuck-in Solid Waste Collection Business [Member] Tuck-in Solid Waste Collection Business [Member] Solid Waste Collection, Transfer and Recycling Business Solid Waste Collection, Transfer and Recycling Business [Member] Solid Waste Collection, Transfer and Recycling Business [Member] Waste Collection, Transfer and Processing Business Collection Business [Member] Collection Business [Member] Solid Waste Collection Solid Waste Collection Business [Member] Solid Waste Collection Business [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Number of businesses acquired Number of Businesses Acquired Useful life of finite lived intangible assets Finite-Lived Intangible Asset, Useful Life Cover page. Document Information [Table] Document Information [Table] Document Information [Line Items] Document Information [Line Items] Document Type Document Type Document Quarterly Report Document Quarterly Report Document Transition Report Document Transition Report Entity Registrant Name Entity Registrant Name Entity File Number Entity File Number Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Current Fiscal Year End Date Current Fiscal Year End Date Entity Central Index Key Entity Central Index Key Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Filer Category Entity Filer Category Title of 12(b) Security Title of 12(b) Security Trading Symbol Trading Symbol Security Exchange Name Security Exchange Name Entity Small Business Entity Small Business Entity Emerging Growth Company Entity Emerging Growth Company Entity Shell Company Entity Shell Company Amendment Flag Amendment Flag Entity Current Reporting Status Entity Current Reporting Status Entity Interactive Data Current Entity Interactive Data Current Entity Tax Identification Number Entity Tax Identification Number Entity Address, Address Line One Entity Address, Address Line One Entity Address, City or Town Entity Address, City or Town Entity Address, State or Province Entity Address, State or Province Entity Address, Postal Zip Code Entity Address, Postal Zip Code City Area Code City Area Code Local Phone Number Local Phone Number Statement of Financial Position [Abstract] ASSETS CURRENT ASSETS: Assets, Current [Abstract] Cash and cash equivalents Accounts receivable - trade, net of allowance for doubtful accounts Accounts Receivable, after Allowance for Credit Loss, Current Refundable income taxes Income Taxes Receivable, Current Prepaid expenses Prepaid Expense, Current Inventory Inventory, Gross Other current assets Other Assets, Current Total current assets Assets, Current Property, plant and equipment, net Property, Plant and Equipment, Net Operating lease right-of-use assets Operating Lease, Right-of-Use Asset Goodwill Intangible assets, net Restricted assets Cost method investments Investments and Other Noncurrent Assets Deferred income taxes Deferred Income Tax Assets, Net Other non-current assets Other Assets, Noncurrent Total assets LIABILITIES AND STOCKHOLDERS' EQUITY (DEFICIT) Liabilities and Equity [Abstract] CURRENT LIABILITIES: Liabilities, Current [Abstract] Current maturities of long-term debt and finance leases Accounts payable Accounts Payable, Current Accrued payroll and related expenses Employee-related Liabilities, Current Accrued interest Interest Payable, Current Current accrued capping, closure and post-closure costs Accrued Capping, Closure, Post-closure and Environmental Costs Current operating lease liabilities Operating Lease, Liability, Current Other accrued liabilities Other Accrued Liabilities, Current Total current liabilities Liabilities, Current Long-term debt and finance leases, less current portion Accrued capping, closure and post-closure costs, less current portion Accrued Capping, Closure, Post-closure and Environmental Costs, Noncurrent Operating lease liabilities, less current portion Operating Lease, Liability, Noncurrent Deferred income taxes Deferred Income Tax Liabilities, Net Other long-term liabilities Other Liabilities, Noncurrent COMMITMENTS AND CONTINGENCIES Commitments and Contingencies STOCKHOLDERS' EQUITY (DEFICIT): Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Casella Waste Systems, Inc. stockholders' equity (deficit) Stockholders' Equity Attributable to Parent [Abstract] Common stock Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital, Common Stock Accumulated deficit Retained Earnings (Accumulated Deficit) Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Total stockholders' equity (deficit) Total liabilities and stockholders' equity (deficit) Liabilities and Equity Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Collection Collection [Member] Collection [Member] Landfill Landfill Revenue [Member] Landfill Revenue [Member] Transfer Transfer [Member] Transfer [Member] Recycling Recycling Revenues [Member] Recycling Revenues [Member] Transportation Transportation [Member] Transportation [Member] Landfill gas-to-energy Landfill - Gas To Energy [Member] Landfill - Gas To Energy [Member] Timing of Transfer of Good or Service [Axis] Timing of Transfer of Good or Service [Axis] Timing of Transfer of Good or Service [Domain] Timing of Transfer of Good or Service [Domain] Transferred at a point-in-time Transferred at Point in Time [Member] Transferred over time Transferred over Time [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Revenue from contracts with customers Revenue from Contract with Customer, Excluding Assessed Tax Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] Beginning balance Asset Retirement Obligation Obligations incurred Asset Retirement Obligation, Liabilities Incurred Revision in estimates Asset Retirement Obligation, Revision of Estimate Accretion expense Asset Retirement Obligation, Accretion Expense Obligations settled Asset Retirement Obligation, Liabilities Settled Ending balance Revolving Credit Facility Revolving Credit Facility [Member] Credit Facility Senior Secured Asset Based Revolving Credit Facility Due Two Thousand And Twenty Three [Member] Senior Secured Asset Based Revolving Credit Facility Due Two Thousand And Twenty Three [Member] Term Loan Facility Term Facility due 2023 (Term Loan A Facility) [Member] Term Facility due 2023 (Term Loan A Facility) [Member] Revolving Credit Facility Due 2023 Revolving Credit Facility Due 2023 [Member] Revolving Credit Facility Due 2023 [Member] Credit Facility [Axis] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Line of Credit Line of Credit [Member] Aggregate principal amount Debt Instrument, Face Amount Credit facility maximum Line of Credit Facility, Maximum Borrowing Capacity Additional revolver capacity Additional Revolver Capacity Amount of additional optional borrowing capacity under the credit facility. Debt instrument, term Debt Instrument, Term Floor interest rate received Derivative, Basis Spread on Variable Rate Net leverage ratio Debt Instrument, Covenant Terms, Net Leverage Ratio Debt Instrument, Covenant Terms, Net Leverage Ratio Line of credit facility, remaining borrowing capacity Line of Credit Facility, Remaining Borrowing Capacity Letters of credit outstanding, amount Letters of Credit Outstanding, Amount Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] SEGMENT REPORTING Segment Reporting Disclosure [Text Block] ACCOUNTING CHANGES New Accounting Pronouncements and Changes in Accounting Principles [Text Block] STOCKHOLDERS' EQUITY Shareholders' Equity and Share-based Payments [Text Block] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Vesting [Axis] Vesting [Axis] Vesting [Domain] Vesting [Domain] Unvested Share-based Payment Arrangement, Tranche One [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Restricted Stock, Restricted Stock Units, and Performance Stock Units Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Outstanding at beginning of period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Class A Common Stock Vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Outstanding at end of period (in shares) Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Outstanding at beginning of period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Granted (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Class A Common Stock Vested (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Forfeited (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Outstanding at end of period (in dollars per share) Weighted Average Remaining Contractual Term (in years) and Aggregate Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract] Weighted Average Remaining Contractual Term, Outstanding Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms Aggregate Intrinsic Value, Outstanding at end of period Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Outstanding Performance-based stock units, percentage of attainment level Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Number of performance-based stock units (in shares) Additional Shares Issued Maximum Attainment Level Additional shares of Class A Common Stock potentially issuable if maximum attainment levels are met. Deferred tax benefit Deferred tax liabilities, goodwill Deferred Tax Liabilities, Goodwill Summary of Purchase Price Paid for Acquisitions Schedule of Business Acquisitions, by Acquisition [Table Text Block] Schedule of Unaudited Pro forma Combined Information Business Acquisition, Pro Forma Information [Table Text Block] Summary of Financial Assets and Liabilities at Fair Value Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Waste Collection Acquisitions Transfer Stations Acquisition [Member] Transfer Stations Acquisition [Member] Purchase Price: Business Combination, Consideration Transferred [Abstract] Cash used in acquisitions, net of cash acquired Notes payable Business Combination, Consideration Transferred, Notes Payable Amount of notes payable incurred by the acquirer as part of consideration transferred in a business combination. Contingent consideration and holdbacks Business Combination, Consideration Transferred, Liabilities Incurred Total Business Combination, Consideration Transferred Allocated as follows: Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract] Current assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets Land Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Land Buildings Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Buildings Equipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Equipment Intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill Other liabilities, net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Deferred tax liability Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Fair value of assets acquired and liabilities assumed Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Excess purchase price allocated to goodwill Summary of Components of Long-Term Debt and Capital Leases by Debt Instrument Schedule of Debt [Table Text Block] Schedule of Cash Flow Hedges Related to Derivative Instruments Schedule of Cash Flow Hedging Instruments, Statements of Financial Performance and Financial Position, Location [Table Text Block] Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Other current assets Other Current Assets [Member] Other non-current assets Other Noncurrent Assets [Member] Other accrued liabilities Other Accrued Liabilities [Member] Other Accrued Liabilities [Member] Other long-term liabilities Other Noncurrent Liabilities [Member] Accumulated other comprehensive loss Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Cash flow hedge derivatives, assets Derivative Asset, Fair Value, Gross Asset Cash flow hedge derivatives, liabilities Derivative Liability, Fair Value, Gross Asset Accumulated other comprehensive loss, interest rate swaps - tax provision Other Comprehensive Income (Loss), Financial Liability, Fair Value Option, Unrealized Gain (Loss) Arising During Period, Tax Accumulated other comprehensive loss Other Comprehensive Income (Loss), Financial Liability, Fair Value Option, Unrealized Gain (Loss) Arising During Period, after Tax Accounts receivable - trade, allowance for doubtful accounts Accounts Receivable, Allowance for Credit Loss, Current Property, plant and equipment, accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, authorized shares (in shares) Common Stock, Shares Authorized Common stock, issued shares (in shares) Common Stock, Shares, Issued Votes per share held Stockholders' Equity, Votes per Share Held Stockholders' Equity, Votes per Share Held BUSINESS COMBINATIONS Business Combination Disclosure [Text Block] Fiscal year ending December 31, 2019 Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year Fiscal year ending December 31, 2020 Finite-Lived Intangible Assets, Amortization Expense, Year Two Fiscal year ending December 31, 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Three Fiscal year ending December 31, 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Four Fiscal year ending December 31, 2023 Finite-Lived Intangible Assets, Amortization Expense, Year Five Thereafter Finite-Lived Intangible Assets, Amortization Expense, after Year Five Lease cost: Lease, Cost [Abstract] Amortization of right-of-use assets Finance Lease, Right-of-Use Asset, Amortization Interest expense Finance Lease, Interest Expense Fixed lease cost Operating Lease, Cost Short-term lease cost Short-term Lease, Cost Variable lease cost Variable Lease, Cost Total lease cost Lease, Cost Other information: Lease, Other Information [Abstract] Lease, Other Information [Abstract] Cash paid for amounts included in the measurement of lease liabilities: Cash Flow, Operating and Financing Activities, Lessee [Abstract] Cash Flow, Operating and Financing Activities, Lessee [Abstract] Financing cash flows for finance leases Finance Lease, Principal Payments Operating cash flows for operating leases Operating Lease, Payments Right-of-use assets obtained in exchange for new finance lease liabilities Right-of-Use Asset Obtained in Exchange for Finance Lease Liability Right-of-use assets obtained in exchange for new operating lease liabilities Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Weighted-average remaining lease term - finance leases (years) Finance Lease, Weighted Average Remaining Lease Term Weighted-average remaining lease term - operating leases (years) Operating Lease, Weighted Average Remaining Lease Term Weighted-average discount rate - finance leases Weighted-average discount rate - operating leases Operating Lease, Weighted Average Discount Rate, Percent LEASES Lessee, Finance Leases [Text Block] LEASES Lessee, Operating Leases [Text Block] Loss Contingencies [Table] Loss Contingencies [Table] Litigation Case [Axis] Litigation Case [Axis] Litigation Case [Domain] Litigation Case [Domain] Notice of Intent to Sue under the Resource Conservation and Recovery Act Notice of Intent to Sue under the Resource Conservation and Recovery Act [Member] Notice of Intent to Sue under the Resource Conservation and Recovery Act [Member] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] MADEP and Casella Waste System Massachusetts Department of Environmental Protection (MADEP) and Casella Waste Systems [Member] Massachusetts Department of Environmental Protection (MADEP) and Casella Waste Systems [Member] 21E Settlement and Water System Construction Funding Agreement 21E Settlement and Water System Construction Funding Agreement [Member] 21E Settlement and Water System Construction Funding Agreement [Member] Bonds Bonds [Member] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Estimate of possible loss Loss Contingency, Estimate of Possible Loss Bond period Amount of costs Environmental Exit Costs, Anticipated Cost Risk free interest percentage rate Accrual for Environmental Loss Contingencies, Discount Rate Scrap yard and solid waste transfer station (in acres) Scrap Yard And Solid Waste Transfer Station Acreage of scrap yard owned by WSI. Undiscounted costs preferred remedies Undiscounted Costs Preferred Remedies Estimated undiscounted remediation costs. Remediation activities, participant share percentage Percentage Participation in Onsite Remediation Activities Percentage participation in onsite remediation activities.