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Weighted-average discount rate - finance leases Finance Lease, Weighted Average Discount Rate, Percent Income Statement Location [Axis] Income Statement Location [Axis] Class A Common Stock Common Class A [Member] Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] Revolving Credit Facility Due 2023 Revolving Credit Facility Due 2023 [Member] Revolving Credit Facility Due 2023 [Member] Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Beginning balance, outstanding (in shares) Ending balance, outstanding (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Thereafter Lessee, Operating Lease, Liability, Payments, Due after Year Five Prepaid expenses, inventories and other assets Increase (Decrease) in Prepaid Expense and Other Assets STOCKHOLDERS' EQUITY Shareholders' Equity and Share-based Payments [Text Block] Recurring Fair Value, Recurring [Member] Fiscal year ending December 31, 2019 Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year Operating income Operating Income (Loss) Operating Income (Loss) Income tax provision related to items of other comprehensive loss Other Comprehensive Income (Loss), Tax Lease liability balance Operating Lease, Liability LEASES Lessee, Finance Leases [Text Block] Other liabilities, net Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Commitments and Contingencies Disclosure [Abstract] Unrecognized stock-based compensation, weighted average period Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Estimated accumulated benefit obligation as complete withdrawal Multiemployer Plans, Complete Withdrawal, Estimated Accumulated Benefit Obligation Multiemployer Plans, Complete Withdrawal, Estimated Accumulated Benefit Obligation Proceeds from property insurance settlement Proceeds from Insurance Settlement, Investing Activities Weighted average Weighted Average [Member] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] ACCRUED FINAL CAPPING, CLOSURE AND POST CLOSURE Asset Retirement Obligation Disclosure [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 Finance Leases Finance Lease, Liability, Payment, Due [Abstract] Debt Instrument [Line Items] Debt Instrument [Line Items] Subsequent event Subsequent Event [Member] Short-term lease cost Short-term Lease, Cost Withdrawal costs - multiemployer pension plan Pension and Other Postretirement Benefits Cost (Reversal of Cost) Accrued payroll and related expenses Employee-related Liabilities, Current Revenues Business Acquisition, Pro Forma Revenue Total Assets, Fair Value Disclosure Issuance of Class A common stock - equity offering Stock Issued During Period, Value, New Issues Reversal of pension costs Pension Cost (Reversal of Cost) Fiscal year ending December 31, 2023 Finite-Lived Intangible Assets, Amortization Expense, Year Five COMMITMENTS AND CONTINGENCIES Commitments and Contingencies LIBOR London Interbank Offered Rate (LIBOR) [Member] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Estimated Minimum Future Finance Lease Obligations Finance Lease, Liability, Maturity [Table Text Block] Statement of Stockholders' Equity [Abstract] 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] Cover page. Revenue, Initial Application Period Cumulative Effect Transition [Table] Revenue, Initial Application Period Cumulative Effect Transition [Table] Inventory Inventory, Gross Recycling Recycling Revenues [Member] Recycling Revenues [Member] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] 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. Less: interest expense Lessee, Operating Lease, Liability, Undiscounted Excess Amount Trading Symbol Trading Symbol Interest rate swaps Interest Rate Derivative Liabilities, at Fair Value Basic earnings per common share (in dollars per share) Earnings Per Share, Basic 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. Thereafter Finance Lease, Liability, Payments, Due after Year Five Document Period End Date Document Period End Date Unregistered Sale Unregistered Sale [Member] Unregistered Sale Other non-cash consideration Business Combination, Consideration Transferred, Other Right-of-use assets obtained in exchange for new finance lease liabilities Right-of-Use Asset Obtained in Exchange for Finance Lease Liability Fiscal year ending December 31, 2022 Lessee, Operating Lease, Liability, Payments, Due Year Four Power generation Solid Waste Operations Power Generation [Member] Solid Waste Operations Power Generation [Member] Unvested restricted stock (in shares) Weighted Average Number of Shares, Restricted Stock Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Cumulative effect of new accounting principle Cumulative Effect of New Accounting Principle in Period of Adoption Derivative Instruments, Gain (Loss) [Table] Derivative Instruments, Gain (Loss) [Table] Revolving Credit Facility Revolving Credit Facility [Member] LONG-TERM DEBT Debt and Capital Leases Disclosures [Text Block] Accounting Standards Update 2014-09 Accounting Standards Update 2014-09 [Member] Common stock Common Stock, Value, Issued Less: interest expense Finance Lease, Liability, Undiscounted Excess Amount Interest expense Interest Expense [Member] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Issuance of Class A common stock - acquisition Stock Issued During Period, Value, Acquisitions Equipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Equipment Landfill gas-to-energy Landfill - Gas To Energy [Member] Landfill - Gas To Energy [Member] Basis of Accounting Basis of Accounting, Policy [Policy Text Block] Solid Waste Collection, Transfer and Recycling Solid Waste Collection, Transfer and Recycling Business [Member] Solid Waste Collection, Transfer and Recycling Business [Member] Cost of operations Cost of Goods and Services Sold Total lease payments Finance Lease, Liability, Payment, Due Stock-based compensation APIC, Share-based Payment Arrangement, Increase for Cost Recognition Net income Business Acquisition, Pro Forma Net Income (Loss) Total assets Assets Cash flow hedge derivatives, liabilities Derivative Liability, Fair Value, Gross Asset Summary of Intangible Amortization Expense Estimated Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Net income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net leverage ratio Debt Instrument, Covenant Terms, Net Leverage Ratio Debt Instrument, Covenant Terms, Net Leverage Ratio Exercisable contractual term at end of period Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Plan Name [Domain] Plan Name [Domain] Transferred over time Transferred over Time [Member] Southbridge landfill closure charge (settlement), net Southbridge Landfill closure charge (settlement), 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. Weighted-average remaining lease term - finance leases (years) Finance Lease, Weighted Average Remaining Lease Term Tuck-in Solid Waste Collection Tuck-in Solid Waste Collection Business [Member] Tuck-in Solid Waste Collection Business [Member] Other non-current assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets Document Fiscal Period Focus Document Fiscal Period Focus Deferred income taxes Deferred Income Tax Expense (Benefit) Document Type Document Type Summary of Purchase Price Paid for Acquisitions Schedule of Business Acquisitions, by Acquisition [Table Text Block] Timing of Transfer of Good or Service [Axis] Timing of Transfer of Good or Service [Axis] Term Loan Facility Term Facility due 2023 (Term Loan A Facility) [Member] Term Facility due 2023 (Term Loan A Facility) [Member] Summary of Financial Assets and Liabilities Measured at Fair Value Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Tax Identification Number Entity Tax Identification Number Weighted average percentage rate paid Derivative, Average Fixed Interest Rate 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 Organics Organics [Member] Organics. Fiscal year ending December 31, 2023 Finance Lease, Liability, Payments, Due Year Five Income Statement [Abstract] Net current-period other comprehensive loss Other Comprehensive Income (Loss), Net of Tax Reduction of goodwill Goodwill, Transfers Estimate of possible loss Loss Contingency, Estimate of Possible Loss LEASES Lessee, Operating Leases [Text Block] Principal amount of long-term debt and finance leases Debt and Lease Obligation Income taxes, net of refunds Income Taxes Paid, Net Other expense (income): Nonoperating Income (Expense) [Abstract] Intangible amortization expense Amortization of Intangible Assets Total operating expenses Costs and Expenses Goodwill [Roll Forward] Goodwill [Roll Forward] Entity Interactive Data Current Entity Interactive Data Current Dilutive effect of stock options and other stock awards (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Number of regional operating segments Number of Operating Segments Use of Estimates Use of Estimates, Policy [Policy Text Block] Provision (benefit) for income taxes Income Tax Expense (Benefit) 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. Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Total current assets Assets, Current Schedule of Estimated Minimum Future Operating Lease Obligations Lessee, Operating Lease, Liability, Maturity [Table Text Block] Income tax provision related to items of other comprehensive (loss) income Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent Hedging Designation [Domain] Hedging Designation [Domain] Fiscal year ending December 31, 2022 Finance Lease, Liability, Payments, Due Year Four Fiscal year ending December 31, 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Four Acquisitions, net of cash acquired Cash used in acquisitions, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Numerator: Net Income (Loss) Available to Common Stockholders, Diluted [Abstract] Total current liabilities Liabilities, Current Number of interest rate derivative agreements Number of Interest Rate Derivatives Held Accounting Changes and Error Corrections [Abstract] Principal payments on long-term debt Repayment of Long-term Debt, Long-term Lease Obligation, and Capital Security General and administration General and Administrative Expense Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Restricted assets Restricted investment securities - landfill closure Restricted Cash and Investments, Noncurrent Environmental Remediation Site [Domain] Environmental Remediation Site [Domain] Aggregate principal amount Debt Instrument, Face Amount Interest income Interest Income, Other Local Phone Number Local Phone Number Landfill operating lease contract expenditures Increase (Decrease) in Operating Lease Liabilities Increase (Decrease) in Operating Lease Liabilities Total liabilities and stockholders' equity (deficit) Liabilities and Equity Non-current assets obtained through long-term obligations Fair Value of Assets Acquired Accounts receivable, net of allowance for doubtful accounts of $1,478 and $931, respectively Accounts Receivable, after Allowance for Credit Loss, Current Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Floor interest rate received Derivative, Basis Spread on Variable Rate Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Equity Components [Axis] Equity Components [Axis] Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Variable Rate [Axis] Variable Rate [Axis] 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 Net income Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent Award Type [Axis] Award Type [Axis] Operating Operating Segments [Member] Undiscounted costs preferred remedies Undiscounted Costs Preferred Remedies Estimated undiscounted remediation costs. Weighted average common shares outstanding Weighted average common shares outstanding, diluted Weighted Average Number of Shares Outstanding, Diluted Fair value of fixed rate debt Debt Instrument, Fair Value Disclosure ACCOUNTING CHANGES New Accounting Pronouncements and Changes in Accounting Principles [Text Block] Landfill Landfill Revenue [Member] Landfill Revenue [Member] Transportation Transportation [Member] Transportation [Member] Fair Value of Financial Instruments Fair Value of Financial Instruments, Policy [Policy Text Block] Votes per share held Stockholders' Equity, Votes per Share Held Stockholders' Equity, Votes per Share Held Summary of Cash Flow Hedges Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Common stock, shares issued Common Stock, Shares, Issued 2006 Incentive Plan Two Thousand Six Stock Incentive Plan [Member] Two thousand six stock incentive plan. Operating lease right-of-use assets Operating Lease, Right-of-Use Asset Fiscal year ending December 31, 2020 Finance Lease, Liability, Payments, Due Year Two Collection Collection [Member] Collection [Member] Disposal Solid Waste Operations Disposal [Member] Solid Waste Operations Disposal [Member] 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] Processing Solid Waste Operations Processing [Member] Solid Waste Operations Processing [Member] Summary of Revenue Attributable to Services Revenue from External Customers by Products and Services [Table Text Block] 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 Number of businesses acquired Number of Businesses Acquired 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] Revision in estimate Asset Retirement Obligation, Revision of Estimate Percentage of attainment level Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Net income Net income Net Income (Loss) Attributable to Parent Forfeited (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Less accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Variable lease cost Variable Lease, Cost Fiscal year ending December 31, 2019 Finance Lease, Liability, Payments, Remainder of Fiscal Year Operating lease right-of-use assets expense Operating Lease, Expense 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] Entity Small Business Entity Small Business Entity File Number Entity File Number Leases Lessee, Leases [Policy Text Block] Other Other Segments [Member] Current operating lease liabilities Operating Lease, Liability, Current Site Contingency [Table] Site Contingency [Table] Schedule of Unaudited Pro forma Combined Information Business Acquisition, Pro Forma Information [Table Text Block] COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Contingent consideration from business combinations Business Combination, Contingent Consideration, Liability Fair value of assets acquired and liabilities assumed Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Contingent liability term Multiemployer Plans, Withdrawal Obligation, Contingent Liability Term Multiemployer Plans, Withdrawal Obligation, Contingent Liability Term Debt instrument, term Bond period Debt Instrument, Term 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 Fiscal year ending December 31, 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Three Summary of Changes in Balances of Each Component of Accumulated Other Comprehensive Loss Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Land Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Land Proceeds from sale of property and equipment Proceeds from Sale of Property, Plant, and Equipment Performance Stock Unit Performance Stock Unit [Member] Performance stock unit. Charlton settlement charge Loss Contingency, Loss in Period Legal and other costs Legal Fees Cash flow hedge derivatives, assets Derivative Asset, Fair Value, Gross Asset Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Other comprehensive loss Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Options, vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Product and Service [Axis] Product and Service [Axis] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Depreciation and amortization Depreciation, Depletion and Amortization Other current assets Other Assets, Current Letters of credit outstanding Letters of Credit Outstanding, Amount Diluted earnings per share attributable to common stockholders: Earnings Per Share, Diluted [Abstract] 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. Other expense, net Nonoperating Income (Expense) CURRENT LIABILITIES: Liabilities, Current [Abstract] Exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Revenue from External Customer [Line Items] Revenue from External Customer [Line Items] Interest Rate Derivative Interest Rate Contract [Member] LIABILITIES AND STOCKHOLDERS' EQUITY (DEFICIT) Liabilities and Equity [Abstract] 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 Total revenues Revenue from Contract with Customer, Excluding Assessed Tax Inter-company revenues Consolidation, Eliminations [Member] Credit Facility [Domain] Credit Facility [Domain] INCOME TAXES Income Tax Disclosure [Text Block] Payments of debt issuance costs Payments of Debt Issuance Costs Segment Reporting [Abstract] Fiscal year ending December 31, 2019 Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year Proceeds from unregistered sale of Class A Common Stock Proceeds from Sale of Common Stock Proceeds from Sale of Common Stock Statement of Cash Flows [Abstract] Interest expense Interest Expense Goodwill and Intangible Assets Disclosure [Abstract] Other comprehensive (loss) income Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent Additional revolver capacity Additional Revolver Capacity Amount of additional optional borrowing capacity under the credit facility. Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Axis] Weighted-average remaining lease term - operating leases (years) Operating Lease, Weighted Average Remaining Lease Term Litigation Case [Axis] Litigation Case [Axis] Site Contingency [Line Items] Site Contingency [Line Items] Derivative Contract [Domain] Derivative Contract [Domain] Diluted earnings per common share (in dollars per share) Business Acquisition, Pro Forma Earnings Per Share, Diluted Proceeds from long-term borrowings Proceeds from Issuance of Long-term Debt and Capital Securities, Net Contract liabilities Contract with Customer, Liability, Current Earnings Per Share [Abstract] Common stock, authorized shares Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Revenue Recognition Revenue [Policy Text Block] Leases [Abstract] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Exercised (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Minimum Minimum [Member] Security Exchange Name Security Exchange Name Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Address, Address Line One Entity Address, Address Line One Basic earnings per common share (in dollars per share) Business Acquisition, Pro Forma Earnings Per Share, Basic CURRENT ASSETS: Assets, Current [Abstract] Client Lists Customer Lists [Member] Schedule of Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Fixed lease cost Operating Lease, Cost Issuance of Class A common stock (in shares) Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture Credit Facility [Axis] Credit Facility [Axis] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Measurement Frequency [Domain] Measurement Frequency [Domain] Statement of Comprehensive Income [Abstract] Scrap yard and solid waste transfer station (in acres) Scrap Yard And Solid Waste Transfer Station Acreage of scrap yard owned by WSI. Covenants Not-to-Compete Noncompete Agreements [Member] Revenues Rebates Revenues Other long-term liabilities Other Liabilities, Noncurrent Obligations incurred Asset Retirement Obligation, Liabilities Incurred EARNINGS PER SHARE Earnings Per Share [Text Block] Class of Stock [Domain] Class of Stock [Domain] Class of Stock [Domain] Accretion expense Asset Retirement Obligation, Accretion Expense Unrecognized stock-based compensation expense Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount Western Western Region [Member] Western region. 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 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. Buildings Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Buildings Allocated as follows: Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract] Southbridge Landfill Southbridge Landfill [Member] Southbridge landfill. 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. Maximum Maximum [Member] Title of 12(b) Security Title of 12(b) Security