Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Outstanding aggregate intrinsic value at end of period Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Other income Other Nonoperating Income (Expense) Net leverage ratio Debt Instrument, Covenant Terms, Net Leverage Ratio Debt Instrument, Covenant Terms, Net Leverage Ratio Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Disposal Solid Waste Operations Disposal [Member] Solid Waste Operations Disposal [Member] Deferred tax liability Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Limited Partners' Capital Account [Line Items] Limited Partners' Capital Account [Line Items] Segments [Axis] Segments [Axis] 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 Summary of Changes in Balances of Each Component of Accumulated Other Comprehensive Loss Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Common stock, additional authorized shares Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Significant Unobservable Inputs (Level 3) Fair Value, Inputs, Level 3 [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] Leases Lessee, Leases [Policy Text Block] Statistical Measurement [Domain] Statistical Measurement [Domain] LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities and Equity [Abstract] Line of Credit Line of Credit [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Unrealized loss resulting from changes in fair value of derivative instruments Accumulated other comprehensive loss, interest rate swaps Other Comprehensive Income (Loss), Financial Liability, Fair Value Option, Unrealized Gain (Loss) Arising During Period, before Tax Amortization of right-of-use assets Finance Lease, Right-of-Use Asset, Amortization Deferred income taxes Deferred Income Tax Liabilities, Net Current Fiscal Year End Date Current Fiscal Year End Date Forward Starting Interest Rate Derivative Forward Interest Rate Contract [Member] Forward Interest Rate Contract Operating income Operating Income (Loss) Operating Income (Loss) Payments of debt issuance costs Payments of Debt Issuance Costs Entity Address, Postal Zip Code Entity Address, Postal Zip Code Total current liabilities Liabilities, Current Amount Reclassified Out of Accumulated Other Comprehensive Income Reclassification out of Accumulated Other Comprehensive Income [Member] Diluted earnings per common share (in dollars per share) Business Acquisition, Pro Forma Earnings Per Share, Diluted Transferred over time Transferred over Time [Member] Outstanding at beginning of period (in dollars per share) Outstanding at end 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 Transportation Transportation [Member] Transportation [Member] Variable Rate [Domain] Variable Rate [Domain] Solid waste operations Solid Waste Operations [Member] Solid waste operations. Variable Rate [Axis] Variable Rate [Axis] Accretion expense Accrual for Environmental Loss Contingencies, Charges to Expense for New Losses Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Total lease payments Finance Lease, Liability, Payment, Due ASSETS Assets: Assets [Abstract] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Options, vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Landfill gas-to-energy Landfill - Gas To Energy [Member] Landfill - Gas To Energy [Member] Issuances of Class A common stock Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture Entity Shell Company Entity Shell Company Class A Common Stock Vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Cover [Abstract] Operating cash flows for operating leases Operating Lease, Payments Accounts payable Accounts Payable, Current Additional revolver capacity Additional Revolver Capacity Amount of additional optional borrowing capacity under the credit facility. Document Type Document Type Allocated as follows: Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract] 2006 Incentive Plan Two Thousand Six Stock Incentive Plan [Member] Two thousand six stock incentive plan. Accumulated deficit Adjustment to retained earnings Retained Earnings (Accumulated Deficit) 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] Operating lease right-of-use assets Operating Lease, Right-of-Use Asset Fiscal year ending December 31, 2021 Lessee, Operating Lease, Liability, to be Paid, Year One Class B Common Stock Common Class B [Member] Beginning balance, outstanding (in shares) Ending balance, outstanding (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Fiscal year ending December 31, 2021 Finance Lease, Liability, to be Paid, Year One STOCKHOLDERS' EQUITY: Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Fiscal year ending December 31, 2024 Lessee, Operating Lease, Liability, to be Paid, Year Four Summary of Financial Assets and Liabilities Measured at Fair Value Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Debt, less current portion Long-term Debt and Lease Obligation New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Summary of Changes to Accrued Capping, Closure and Post-Closure Liabilities Schedule of Change in Asset Retirement Obligation [Table Text Block] Hedging Designation [Domain] Hedging Designation [Domain] Total lease cost Lease, Cost Document Quarterly Report Document Quarterly Report Exercisable at end of period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Other long-term liabilities Other Liabilities, Noncurrent Deferred income taxes Deferred Income Tax Assets, Net Forfeited (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Financing cash flows for finance leases Finance Lease, Principal Payments AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] Stock-based compensation APIC, Share-based Payment Arrangement, Increase for Cost Recognition Beginning balance Ending balance Asset Retirement Obligation Adjustments Difference between Revenue Guidance in Effect before and after Topic 606 [Member] Land Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Land Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Restricted Stock, Restricted Stock Units And Performance Stock Units Restricted Stock Restricted Stock Units And Performance Stock Units [Member] Restricted stock, restricted stock units and performance stock units. Total revenues Revenue from Contract with Customer, Excluding Assessed Tax Measurement Frequency [Domain] Measurement Frequency [Domain] Debt And Derivatives Disclosure [Abstract] Debt And Derivatives Disclosure [Abstract] Accrued capping, closure and post-closure costs, less current portion Accrued Capping, Closure, Post-closure and Environmental Costs, Noncurrent Entity File Number Entity File Number Business Acquisition [Axis] Business Acquisition [Axis] Options granted, term Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period 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 2.875% Revenue Bonds Series Two Thousand Fourteen Due Two Thousand Forty Four [Member] Revenue Bonds Series Two Thousand Fourteen Due Two Thousand Forty Four [Member] Undiscounted costs preferred remedies Undiscounted Costs Preferred Remedies Estimated undiscounted remediation costs. Statement [Line Items] Statement [Line Items] Issuance of Class A common stock - acquisition (in shares) Stock Issued During Period, Shares, Acquisitions Forecast Forecast [Member] Class of Stock [Domain] Class of Stock [Domain] Class of Stock [Domain] Tuck-in Solid Waste Collection Business Tuck-in Solid Waste Collection Business [Member] Tuck-in Solid Waste Collection Business [Member] Debt instrument, term Bond period Debt Instrument, Term Document Fiscal Period Focus Document Fiscal Period Focus Obligations incurred Accrual For Environmental Loss Contingencies, Obligations Incurred Accrual For Environmental Loss Contingencies, Obligations Incurred Site Contingency [Line Items] Site Contingency [Line Items] Accrued interest Interest Payable, Current Statement [Table] Statement [Table] Statistical Measurement [Axis] Statistical Measurement [Axis] Gross receivables from contracts Contract with Customer, Asset, before Allowance for Credit Loss, Current Legal and other costs Legal Fees Credit Facility [Axis] Credit Facility [Axis] Fixed rate debt Debt Instrument, Fair Value Disclosure Unusual or Infrequent Items, or Both [Abstract] Interest income Interest Income, Other Weighted average Weighted Average [Member] Business Combinations [Abstract] Interest rate swap amounts reclassified into interest expense Other comprehensive loss, reclassification adjustment from AOCI Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax Performance Stock Unit Performance Stock Unit [Member] Performance stock unit. Asset Retirement Obligation Disclosure [Abstract] Thereafter Finite-Lived Intangible Asset, Expected Amortization, after Year Four Finite-Lived Intangible Asset, Expected Amortization, after Year Four Operating Leases Lessee, Operating Lease, Liability, Payment, Due [Abstract] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Exercisable contractual term at end of period Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Prepaid expenses Prepaid Expense, Current Proceeds from the public issuance of Class A Common Stock Proceeds from Issuance of Common Stock 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] Goodwill [Roll Forward] Goodwill [Roll Forward] Summary of Earnings per Share Computation Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Votes per share held Stockholders' Equity, Votes per Share Held Stockholders' Equity, Votes per Share Held Common stock, authorized shares Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized LEASES Lessee, Finance Leases [Text Block] Amendment Flag Amendment Flag Number of shares available for future grant Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Other accrued liabilities Other Accrued Liabilities, Current NCES Landfil NCES Landfil [Member] NCES Landfil Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Other comprehensive loss, before tax: Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract] Measurement Frequency [Axis] Measurement Frequency [Axis] 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] Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition [Axis] Derivative Instrument [Axis] Derivative Instrument [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Other long-term liabilities Other Noncurrent Liabilities [Member] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Summary of Intangible Assets by Intangible Asset Type Schedule of Finite-Lived Intangible Assets [Table Text Block] Refundable income taxes Income Taxes Receivable, Current Local Phone Number Local Phone Number Accrual for Environmental Loss Contingencies [Roll Forward] Accrual for Environmental Loss Contingencies [Roll Forward] Segments [Domain] Segments [Domain] Landfill Landfill Revenue [Member] Landfill Revenue [Member] Statement of Cash Flows [Abstract] Southbridge Landfill closure charge Southbridge Landfill Closure Charge The aggregate (recovery) charge recognized in the period associated with the unplanned closure of the Southbridge Landfill. (Recovery) charges are expected to be incurred through completion of the closure process Net income Business Acquisition, Pro Forma Net Income (Loss) Property, Plant and Equipment, Type [Axis] Long-Lived Tangible Asset [Axis] Summary of Restricted Stock, Restricted Stock Unit and Performance Stock Unit Activity Share-based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block] Summary of Revenue Attributable to Services Revenue from External Customers by Products and Services [Table Text Block] Income Statement Location [Axis] Income Statement Location [Axis] Accounts receivable - trade, allowance for doubtful accounts Balance at beginning of period Balance at end of period Accounts Receivable, Allowance for Credit Loss, Current Southbridge Landfill Southbridge Landfill [Member] Southbridge landfill. Issuance of Class A common stock - acquisition Stock Issued During Period, Value, Acquisitions Income Statement Location [Domain] Income Statement Location [Domain] Interest rate swap settlements Other Comprehensive Income (Loss), Derivative, Excluded Component, Increase (Decrease), Adjustments, before Tax Fiscal year ending December 31, 2022 Lessee, Operating Lease, Liability, to be Paid, Year Two 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] Notional amount Derivative, Notional Amount Intangible amortization expense Amortization of Intangible Assets Schedule of Lease Costs and Other Lease Information Lease, Cost [Table Text Block] Landfill operating lease contract expenditures Increase (Decrease) in Landfill Operating Lease Contract Expenditures Increase (decrease) in landfill operating lease liabilities associated with landfill operating lease contract payments Entity Current Reporting Status Entity Current Reporting Status Debt less unamortized debt issuance costs Long-term Debt and Lease Obligation, Including Current Maturities Fiscal year ending December 31, 2023 Lessee, Operating Lease, Liability, to be Paid, Year Three Other non-current assets Other Assets, Noncurrent Plan Name [Axis] Plan Name [Axis] Transfer Transfer [Member] Transfer [Member] SEGMENT REPORTING Segment Reporting Disclosure [Text Block] Issuance of Class A common stock - equity offering Stock Issued During Period, Value, New Issues Net income Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent Total assets Total assets Assets Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] Scenario [Axis] Scenario [Axis] Summary of Environmental Liability Schedule of Environmental Loss Contingencies by Site [Table Text Block] Outstanding, beginning of period (in shares) Outstanding, end of period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number 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 Finance Leases Finance Lease, Liability, Payment, Due [Abstract] Intangible assets, net Intangible assets, net Finite-Lived Intangible Assets, Net Collection Solid Waste Operations Collection [Member] Solid Waste Operations Collection [Member] Credit Loss [Abstract] BASIS OF PRESENTATION Business Description and Basis of Presentation [Text Block] Entity Small Business Entity Small Business Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Axis] Vesting [Domain] Vesting [Domain] Schedule of Estimated Minimum Future Finance Lease Obligations Finance Lease, Liability, Fiscal Year Maturity [Table Text Block] Interest expense Interest Expense Environmental Remediation Site [Domain] Environmental Remediation Site [Domain] Depreciation and amortization Depreciation, Depletion and Amortization Entity Filer Category Entity Filer Category Revenue, Initial Application Period Cumulative Effect Transition [Line Items] Revenue, Initial Application Period Cumulative Effect Transition [Line Items] Schedule of New Accounting Pronouncements and Changes in Accounting Principles Accounting Standards Update and Change in Accounting Principle [Table Text Block] Environmental Remediation Site [Axis] Environmental Remediation Site [Axis] Product and Service [Axis] Product and Service [Axis] Restricted assets Restricted investment securities - landfill closure Restricted Cash and Investments, Noncurrent Entity Address, City or Town Entity Address, City or Town Transferred at a point-in-time Transferred at Point in Time [Member] Unrecognized stock-based compensation, weighted average period Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Corporate entities Other Segments [Member] Revolving credit facility Lines of Credit, Fair Value Disclosure Less: interest expense Lessee, Operating Lease, Liability, Undiscounted Excess Amount Commitments and Contingencies Disclosure [Abstract] Quoted Prices in Active Markets for Identical Assets (Level 1) Fair Value, Inputs, Level 1 [Member] Obligations settled Asset Retirement Obligation, Liabilities Settled Operating lease right-of-use assets expense Operating Lease, Expense Loss from derivative instrument Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Site Contingency [Table] Site Contingency [Table] Weighted average interest rate Debt, Weighted Average Interest Rate Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Document Fiscal Year Focus Document Fiscal Year Focus Cash flow hedge derivatives, liabilities Derivative Liability, Fair Value, Gross Asset Accounts payable Increase (Decrease) in Accounts Payable 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] Other information: Lease, Other Information [Abstract] Lease, Other Information [Abstract] Aggregate intrinsic value at end of period Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Outstanding Thereafter Lessee, Operating Lease, Liability, to be Paid, after Year Four Lessee, Operating Lease, Liability, to be Paid, after Year Four Timing of Transfer of Good or Service [Domain] Timing of Transfer of Good or Service [Domain] Debt Instrument [Axis] Debt Instrument [Axis] Additional Paid-In Capital Additional Paid-in Capital [Member] ACCRUED FINAL CAPPING, CLOSURE AND POST CLOSURE Asset Retirement Obligation Disclosure [Text Block] Summary of Purchase Price Paid for Acquisitions Schedule of Business Acquisitions, by Acquisition [Table Text Block] Inventory Inventory, Gross Operating Operating Segments [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] 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] Accrued expenses, contract liabilities and other liabilities Increase (Decrease) in Accrued Liabilities Term Loan Facility Term Facility due October 2023 (Term Loan B Facility) [Member] Term Facility due October 2023 (Term Loan B Facility) [Member] Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Litigation Case [Axis] Litigation Case [Axis] Notes payable maturing through June 2027; bearing interest at a weighted average of 3.5% Notes Payable [Member] Notes Payable [Member] Interest expense Finance Lease, Interest Expense Revenue from Contract with Customer [Abstract] Environmental remediation charge Environmental Remediation Expense Vehicles, equipment and property Machinery and Equipment [Member] Fair Value of Financial Instruments Fair Value of Financial Instruments, Policy [Policy Text Block] Common stock, shares outstanding Beginning balance (in shares) Ending balance (in shares) Common Stock, Shares, Outstanding Variable lease cost Variable Lease, Cost 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] Revolving Credit Facility Revolving Credit Facility [Member] Schedule of Goodwill [Table] Schedule of Goodwill [Table] Income before income taxes Income before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Beginning balance, outstanding (in dollars per share) Ending balance, outstanding (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Accounting Changes and Error Corrections [Abstract] Letters of credit outstanding Letters of Credit Outstanding, Amount Acquisitions, net of cash acquired Cash used in acquisitions, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Common stock, shares authorized Common Stock, Shares Authorized Dilutive effect of stock options and other stock awards (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Current maturities of debt Less—current maturities of debt Long-term Debt and Lease Obligation, Current Waste Collection Acquisitions Transfer Stations Acquisition [Member] Transfer Stations Acquisition [Member] Initial Application Period Cumulative Effect Transition [Domain] Initial Application Period Cumulative Effect Transition [Domain] Summary of Segment Reporting Information by Segment Schedule of Segment Reporting Information, by Segment [Table Text Block] Revisions in estimates Accrual for Environmental Loss Contingencies, Revision in Estimates Contingent consideration and holdbacks Business Combination, Consideration Transferred, Liabilities Incurred Document Period End Date Document Period End Date Entity Registrant Name Entity Registrant Name Fair Value Estimate of Fair Value Measurement [Member] Income Statement [Abstract] Accumulated other comprehensive loss AOCI Attributable to Parent [Member] Operating lease liabilities, less current portion Operating Lease, Liability, Noncurrent Fiscal year ending December 31, 2024 Finite-Lived Intangible Asset, Expected Amortization, Year Four Prepaid expenses, inventories and other assets Increase (Decrease) in Prepaid Expense and Other Assets 2016 Plan 2016 Incentive Plan [Member] 2016 Incentive Plan ACCOUNTS RECEIVABLE, NET OF ALLOWANCE FOR CREDIT LOSSES Credit Loss, Financial Instrument [Text Block] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Use of Estimates Use of Estimates, Policy [Policy Text Block] CURRENT ASSETS: Assets, Current [Abstract] Power generation Solid Waste Operations Power Generation [Member] Solid Waste Operations Power Generation [Member] Cash Flows from Investing Activities: Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Fiscal year ending December 31, 2023 Finance Lease, Liability, to be Paid, Year Three Current accrued capping, closure and post-closure costs Accrued Capping, Closure, Post-closure and Environmental Costs 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. Scenario [Domain] Scenario [Domain] Additions to property, plant and equipment Payments to Acquire Property, Plant, and Equipment Consolidation Items [Domain] Consolidation Items [Domain] Document Information [Line Items] Document Information [Line Items] Entity Tax Identification Number Entity Tax Identification Number Net income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Client Lists Customer Lists [Member] Schedule of Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Trading Symbol Trading Symbol accumulated other comprehensive loss Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax 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] Hedging Designation [Axis] Hedging Designation [Axis] Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] Collection Collection [Member] Collection [Member] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Obligations incurred Asset Retirement Obligation, Liabilities Incurred Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Stock-based compensation Share-based Payment Arrangement, Noncash Expense Legal Entity [Axis] Legal Entity [Axis] Designated as Hedging Instrument Designated as Hedging Instrument [Member] Acquisitions Goodwill, Acquired During Period Schedule of Limited Partners' Capital Account by Class [Table] Schedule of Limited Partners' Capital Account by Class [Table] Other comprehensive loss Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Entity [Domain] Entity [Domain] Derivative Instruments, Gain (Loss) [Table] Derivative Instruments, Gain (Loss) [Table] GOODWILL AND INTANGIBLE ASSETS Intangible Assets Disclosure [Text Block] Risk free interest percentage rate Accrual for Environmental Loss Contingencies, Discount Rate Goodwill [Line Items] Goodwill [Line Items] LEASES Lessee, Operating Leases [Text Block] Fair Value Disclosures [Abstract] Principal amount of debt Debt and Lease Obligation City Area Code City Area Code Cost of operations Cost of Goods and Services Sold Lease cost: Lease, Cost [Abstract] Total operating expenses Costs and Expenses Equity Components [Axis] Equity Components [Axis] Title of 12(b) Security Title of 12(b) Security Accrued Final Capping, Closure and Post Closure Asset Retirement Obligation [Policy Text Block] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Minimum Minimum [Member] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Accumulated other comprehensive loss Other Comprehensive Income (Loss), Financial Liability, Fair Value Option, Unrealized Gain (Loss) Arising During Period, after Tax Summary of Changes to Allowance for Credit Losses Accounts Receivable, Allowance for Credit Loss [Table Text Block] Revenue from External Customer [Line Items] Revenue from External Customer [Line Items] Current operating lease liabilities Operating Lease, Liability, Current 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] Unrecognized stock-based compensation expense Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount Right-of-use assets obtained in exchange for new finance lease liabilities Right-of-Use Asset Obtained in Exchange for Finance Lease Liability 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 Current assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets Derivative Instruments, Gain (Loss) [Line Items] Derivative Instruments, Gain (Loss) [Line Items] Summary of Cash Flow Hedges Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Exercised (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price FAIR VALUE OF FINANCIAL INSTRUMENTS Fair Value Disclosures [Text Block] 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] Cash Flows from Operating Activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Resource solutions operations Resource Solutions Operations [Member] Resource Solutions Operations Summary of Stock Option Activity Share-based Payment Arrangement, Option, Activity [Table Text Block] Accounts, Notes, Loans and Financing Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Interest rate swaps Interest Rate Swap [Member] Fiscal year ending December 31, 2020 Finite-Lived Intangible Asset, Expected Amortization, Remainder of Fiscal Year Number of landfill operation and management agreements Number of Landfill Operation and Management Agreements Entered Into Number of Landfill Operation and Management Agreements Entered Into Weighted Average Remaining Contractual Term (years) and Aggregate Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract] Cumulative effect of new accounting principle Cumulative Effect, Period of Adoption, Adjustment [Member] Additional paid-in capital Additional Paid in Capital, Common Stock Restricted Stock Restricted Stock Awards [Member] Restricted Stock Awards [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Statement of Stockholders' Equity [Abstract] Weighted-average discount rate - operating leases Operating Lease, Weighted Average Discount Rate, Percent Landfill Landfill [Member] Accounts Receivable, Allowance for Credit Loss [Roll Forward] Accounts Receivable, Allowance for Credit Loss [Roll Forward] Proceeds from sale of property and equipment Proceeds from Sale of Property, Plant, and Equipment Less - unamortized debt issuance costs Debt Issuance Costs, Net Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Less: interest expense Finance Lease, Liability, Undiscounted Excess Amount Credit Facility Credit Facility [Member] Credit Facility [Member] Consolidation Items [Axis] Consolidation Items [Axis] Impact of potentially dilutive securities: Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract] Effect of weighted average shares outstanding (in shares) Weighted Average Number of Shares Issued, Basic Notice of Intent to Sue for Violations of the CWA Notice of Intent to Sue for Violations of the CWA [Member] Notice of Intent to Sue for Violations of the CWA Accounts receivable, net of allowance for credit losses of $2,615 and $1,468, respectively Accounts Receivable, after Allowance for Credit Loss, Current Total lease payments Lessee, Operating Lease, Liability, to be Paid Adjustments for New Accounting Pronouncements [Axis] Accounting Standards Update [Axis] Basic earnings per common share (in dollars per share) Business Acquisition, Pro Forma Earnings Per Share, Basic Goodwill Excess purchase price allocated to goodwill Goodwill, beginning balance Goodwill, ending balance Goodwill Principal payments on debt Repayment of Long-term Debt, Long-term Lease Obligation, and Capital Security Other comprehensive loss, net of tax Hedging activity Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Title of Individual [Axis] Title of Individual [Axis] Timing of Transfer of Good or Service [Axis] Timing of Transfer of Good or Service [Axis] Non-current assets obtained through long-term obligations Fair Value of Assets Acquired Other expense (income): Nonoperating Income (Expense) [Abstract] Aggregate principal amount Debt Instrument, Face Amount Significant Other Observable Inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Eastern Eastern Region [Member] Eastern region. Other current assets Other Assets, Current Vesting [Axis] Vesting [Axis] MADEP and Casella Waste Systems Massachusetts Department of Environmental Protection (MADEP) and Casella Waste Systems [Member] Massachusetts Department of Environmental Protection (MADEP) and Casella Waste Systems [Member] Summary of Goodwill Activity Schedule of Goodwill [Table Text Block] Equity [Abstract] Non-cash expense from acquisition activities Non-Cash Expense From Acquisition Activities The non-cash portion of the aggregate amount of expense associated with legal, consulting and other similar costs recognized during the accounting period associated with the acquisition and integration of acquired businesses or select development projects Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Other comprehensive loss, before tax Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent Supplemental Disclosure of Non-Cash Investing and Financing Activities: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Entity Central Index Key Entity Central Index Key Contract liabilities Contract with Customer, Liability, Current Entity Emerging Growth Company Entity Emerging Growth Company Accounting standards update Accounting Standards Update [Extensible List] Granted (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Cumulative Effect, Period of Adoption [Axis] Cumulative Effect, Period of Adoption [Axis] Credit Facility [Domain] Credit Facility [Domain] ACCOUNTING CHANGES Accounting Standards Update and Change in Accounting Principle [Text Block] Derivative Contract [Domain] Derivative Contract [Domain] Summary of Intangible Amortization Expense Estimated Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Weighted average common shares outstanding Weighted average common shares outstanding, diluted Weighted Average Number of Shares Outstanding, Diluted Litigation Case [Domain] Litigation Case [Domain] Basic earnings per common share (in dollars per share) Earnings Per Share, Basic Number of additional shares Additional Shares Issued Maximum Attainment Level Additional shares of Class A Common Stock potentially issuable if maximum attainment levels are met. Organics Organics [Member] Organics. Number of regional operating segments Number of Operating Segments Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Weighted-average remaining lease term - operating leases (years) Operating Lease, Weighted Average Remaining Lease Term Buildings Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Buildings Other accrued liabilities Other Accrued Liabilities [Member] Other Accrued Liabilities [Member] Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities Stock-based compensation expense Share-based Payment Arrangement, Expense Number of citizens seeking damages Loss Contingency, Number of Plaintiffs Western Western Region [Member] Western region. Balance Sheet Location [Axis] Balance Sheet Location [Axis] Common stock Common Stock, Value, Issued Goodwill and Intangible Assets Disclosure [Abstract] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Fiscal year ending December 31, 2022 Finite-Lived Intangible Asset, Expected Amortization, Year Two Proceeds from debt borrowings Proceeds from Issuance of Long-term Debt and Capital Securities, Net Income tax benefit related to items of other comprehensive loss Income tax benefit related to items of other comprehensive loss Provision (benefit) for income taxes Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent Exercisable aggregate intrinsic value at end of period Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Fiscal year ending December 31, 2024 Finance Lease, Liability, to be Paid, Year Four Bonds Bonds [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 2029; bearing interest at 2.95% Revenue Bond Series Two Thousand Thirteen Due Two Thousand Twenty Nine [Member] Revenue Bond Series Two Thousand Thirteen Due Two Thousand Twenty Nine [Member] Issuance of Class A common stock (in shares) Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Fair value of assets acquired and liabilities assumed Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net 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 Percentage of attainment level Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Obligations settled Accrual for Environmental Loss Contingencies, Payments Common stock, shares issued Common Stock, Shares, Issued Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Revenue from External Customers by Products and Services [Table] Revenue from External Customers by Products and Services [Table] Lease liability balance Operating Lease, Liability Segment Reporting [Abstract] Interest expense Interest Expense [Member] Accounts receivable Increase (Decrease) in Accounts Receivable Debt Instrument [Line Items] Debt Instrument [Line Items] Statement of Comprehensive Income [Abstract] Total stockholders' equity Beginning balance Ending balance Stockholders' Equity Attributable to Parent Interest accretion on landfill and environmental remediation liabilities Accretion Expense, Including Asset Retirement Obligations Total Business Combination, Consideration Transferred Total liabilities and stockholders' equity Liabilities and Equity Cash paid during the period for: Supplemental Cash Flow Information, Cash Paid [Abstract] Supplemental Cash Flow Information, Cash Paid Loss Contingencies [Line Items] Loss Contingencies [Line Items] Number of businesses acquired Number of Businesses Acquired Accounting Standards Update 2014-09 Accounting Standards Update 2014-09 [Member] Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Portion at Fair Value Measurement [Member] Portion at Fair Value Measurement [Member] Accrued payroll and related expenses Employee-related Liabilities, Current Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Restricted Stock Unit Restricted Stock Units (RSUs) [Member] Fixed lease cost Operating Lease, Cost Other liabilities, net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Hedging Relationship [Axis] Hedging Relationship [Axis] General and administration General and Administrative Expense Type of Adoption [Domain] Accounting Standards Update [Domain] Anti-dilutive potentially issuable shares Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Floor interest rate Derivative, Floor Interest Rate Customer solutions Customer Solutions [Member] Customer solutions. Revolving Credit Facility Due 2023 Revolving Credit Facility Due 2023 [Member] Revolving Credit Facility Due 2023 [Member] Weighted-average remaining lease term - finance leases (years) Finance Lease, Weighted Average Remaining Lease Term Short-term lease cost Short-term Lease, Cost Loss (gain) on sale of property and equipment Gain (Loss) on Disposition of Property Plant Equipment Useful life of finite lived intangible assets Finite-Lived Intangible Asset, Useful Life Equity Component [Domain] Equity Component [Domain] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Liabilities: Liabilities [Abstract] Entity Address, Address Line One Entity Address, Address Line One Term Loan Facility Term Facility due 2023 (Term Loan A Facility) [Member] Term Facility due 2023 (Term Loan A Facility) [Member] Property, plant and equipment, net of accumulated depreciation and amortization of $879,090 and $844,874, respectively Property, Plant and Equipment, Net Fiscal year ending December 31, 2023 Finite-Lived Intangible Asset, Expected Amortization, Year Three Interest Rate Derivative Interest Rate Contract [Member] Net income Net income Net Income (Loss) Attributable to Parent Entity Address, State or Province Entity Address, State or Province Changes in assets and liabilities, net of effects of acquisitions and divestitures: Increase (Decrease) in Operating Capital [Abstract] Fiscal year ending December 31, 2020 Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year LIBOR London Interbank Offered Rate (LIBOR) [Member] Leases [Abstract] Weighted average percentage rate paid Derivative, Average Fixed Interest Rate Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Total current assets Assets, Current Number of interest rate derivative agreements Number of Interest Rate Derivatives Held Interest rate swaps Interest Rate Derivative Liabilities, at Fair Value Earnings Per Share [Abstract] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Lease liability balance Finance leases maturing through December 2107; bearing interest at a weighted average of 4.6% Finance Lease, Liability Southbridge Landfill non-cash closure charge Southbridge Landfill Non-cash Closure Charge The non-cash portion of the aggregate (recovery) charge recognized in the period associated with the unplanned closure of the Southbridge Landfill. (Recovery) charges are expected to be incurred through completion of the closure process 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. Casella Waste Systems, Inc. stockholders' equity Stockholders' Equity Attributable to Parent [Abstract] Intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Entity Interactive Data Current Entity Interactive Data Current Stock Options Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Subsequent Events Subsequent Events, Policy [Policy Text Block] Processing Solid Waste Operations Processing [Member] Solid Waste Operations Processing [Member] Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Supplemental Disclosure of Cash Flow Information: Supplemental Cash Flow Information [Abstract] Cost method investments Investments and Other Noncurrent Assets Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Resource Solutions Resource Solutions Region [Member] Resource Solutions Region [Member] Estimate of possible loss Loss Contingency, Estimate of Possible Loss Common Stock Common Stock [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Product and Service [Domain] Product and Service [Domain] Property, Plant and Equipment, Type [Domain] Long-Lived Tangible Asset [Domain] DEBT Debt and Capital Leases Disclosures [Text Block] Summary of Reclassifications Out of Accumulated Other Comprehensive Loss Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Weighted-average discount rate - finance leases Finance Lease, Weighted Average Discount Rate, Percent Fixed Rate Bonds Fixed Rate Bonds [Member] Fixed rate bonds. Reclassification out of Accumulated Other Comprehensive Income [Table] Reclassification out of Accumulated Other Comprehensive Income [Table] Secured Debt Secured Debt [Member] Line of credit facility, remaining borrowing capacity Line of Credit Facility, Remaining Borrowing Capacity Issuance of Class A common stock - equity offering (in shares) Stock Issued During Period, Shares, New Issues Thereafter Finance Lease, Liability, to be Paid, after Year Four Finance Lease, Liability, to be Paid, after Year Four Scrap yard and solid waste transfer station (in acres) Scrap Yard And Solid Waste Transfer Station Acreage of scrap yard owned by WSI. Intangible assets Finite-Lived Intangible Assets, Gross Unvested restricted stock (in shares) Weighted Average Number of Shares, Restricted Stock Stated interest rate Debt Instrument, Interest Rate, Stated Percentage Additions - charged to expense Accounts Receivable, Credit Loss Expense (Reversal) Accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Class A Common Stock Common Class A [Member] Recovery credited to environmental remediation expense Environmental Costs Recognized, Recovery Credited to Expense Diluted earnings per share attributable to common stockholders: Earnings Per Share, Diluted [Abstract] Exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Revenue recognized fro performance obligation satisfied in previous period Contract with Customer, Performance Obligation Satisfied in Previous Period 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] Net decrease in cash and cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect BUSINESS COMBINATIONS Business Combination Disclosure [Text Block] Other expense, net Nonoperating Income (Expense) Hedging Relationship [Domain] Hedging Relationship [Domain] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Schedule of Estimated Minimum Future Operating Lease Obligations Lessee, Operating Lease, Liability, Maturity [Table Text Block] Ontario County, New York Class Action Litigation Ontario County, New York Class Action Litigation [Member] Ontario County, New York Class Action Litigation Stock Options Share-based Payment Arrangement, Option [Member] Basis of Accounting Basis of Accounting, Policy [Policy Text Block] Proceeds from Hedge, Investing Activities Proceeds from Hedge, Investing Activities Weighted average common shares outstanding Weighted average common shares outstanding, basic Weighted Average Number of Shares Outstanding, Basic Basis spread on variable rate Debt Instrument, Basis Spread on Variable Rate Operating expenses: Costs and Expenses [Abstract] 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] Cash Flow Hedging Cash Flow Hedging [Member] Loss Contingencies [Table] Loss Contingencies [Table] Carrying Value Reported Value Measurement [Member] Plan Name [Domain] Plan Name [Domain] REVENUE RECOGNITION Revenue from Contract with Customer [Text Block] Interest Interest Paid, Excluding Capitalized Interest, Operating Activities Hedging activity: Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, before Tax [Abstract] Right-of-use assets obtained in exchange for new operating lease liabilities Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Fiscal year ending December 31, 2020 Finance Lease, Liability, to be Paid, Remainder of Fiscal Year STOCKHOLDERS' EQUITY Shareholders' Equity and Share-based Payments [Text Block] Fiscal year ending December 31, 2021 Finite-Lived Intangible Asset, Expected Amortization, Year One Revenues Rebates Revenues Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Axis] Shares to be issued - acquisition Weighted Average Number of Shares, Contingently Issuable Remediation activities, participant share percentage Percentage Participation in Onsite Remediation Activities Percentage participation in onsite remediation activities. Provision (benefit) for income taxes Income Tax Expense (Benefit) Income taxes, net of refunds Income Taxes Paid, Net Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents New Accounting Pronouncements or Change in Accounting Principle [Table] Accounting Standards Update and Change in Accounting Principle [Table] Title of Individual [Domain] Title of Individual [Domain] Diluted earnings per common share (in dollars per share) Earnings Per Share, Diluted Schedule of Unaudited Pro forma Combined Information Business Acquisition, Pro Forma Information [Table Text Block] Cumulative Effect, Period of Adoption [Domain] Cumulative Effect, Period of Adoption [Domain] Unvested Share-based Payment Arrangement, Tranche One [Member] Aggregate intrinsic value of options exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Summary of Long-term Debt and Finance Leases by Debt Instrument Schedule of Debt [Table Text Block] Numerator: Net Income (Loss) Available to Common Stockholders, Diluted [Abstract] Environmental remediation liability Beginning balance Ending balance Accrual for Environmental Loss Contingencies Interest Rate Swaps Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member] Equipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Equipment Inter-company revenues Consolidation, Eliminations [Member] Purchase Price: Business Combination, Consideration Transferred [Abstract] Covenants Not-to-Compete Noncompete Agreements [Member] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Revenues Business Acquisition, Pro Forma Revenue Recycling Recycling Revenues [Member] Recycling Revenues [Member] Deferred income taxes Deferred Income Tax Expense (Benefit) Non Employee Director Non Employee Director [Member] Non Employee Director [Member] Credit facility maximum Line of Credit Facility, Maximum Borrowing Capacity Award Type [Axis] Award Type [Axis] 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] Potsdam Environmental Remediation Potsdam Environmental Liability [Member] Potsdam environmental liability. Less accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Fair value of stock awards vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Maximum Maximum [Member] Amortization of debt issuance costs Amortization of Debt Issuance Costs Security Exchange Name Security Exchange Name Document Information [Table] Document Information [Table] OTHER ITEMS AND CHARGES Unusual or Infrequent Items, or Both, Disclosure [Text Block] Accumulated Deficit Retained Earnings [Member] Measurement Basis [Axis] Measurement Basis [Axis] Revision in estimates Asset Retirement Obligation, Revision of Estimate Expense from acquisition activities Expense from Acquisition Activities The aggregate amount of expense associated with legal, consulting and other similar costs recognized during the accounting period associated with the acquisition and integration of acquired businesses or select development projects 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] Anticipated cost Environmental Exit Costs, Anticipated Cost Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Weighted Average Remaining Contractual Term (years) and Aggregate Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Outstanding contractual term at end of period Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Award Type [Domain] Award Type [Domain] Document Transition Report Document Transition Report Floor interest rate received Derivative, Basis Spread on Variable Rate Denominators: Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Exercisable at end of period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Recycling Operation Recycling Operation [Member] Recycling Operation Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Contractual term at end of period Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms Proceeds from the exercise of share based awards Proceeds, Issuance of Shares, Share-based Payment Arrangement, Including Option Exercised Revenue, Initial Application Period Cumulative Effect Transition [Table] Revenue, Initial Application Period Cumulative Effect Transition [Table] EARNINGS PER SHARE Earnings Per Share [Text Block] Deductions - bad debts written off, net of recoveries Accounts Receivable, Allowance for Credit Loss, Writeoff (Recoveries) Accounts Receivable, Allowance for Credit Loss, Writeoff (Recoveries) Organization, Consolidation and Presentation of Financial Statements [Abstract] CURRENT LIABILITIES: Liabilities, Current [Abstract] Cash Flows from Financing Activities: Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Accretion expense Asset Retirement Obligation, Accretion Expense Recurring Fair Value, Recurring [Member] Fiscal year ending December 31, 2022 Finance Lease, Liability, to be Paid, Year Two Segment Reporting Segment Reporting, Policy [Policy Text Block] Accounting Standards that are Adopted and Pending Adoption New Accounting Pronouncements, Policy [Policy Text Block] Statement of Financial Position [Abstract] Basic earnings per share attributable to common stockholders: Earnings Per Share, Basic [Abstract]