Casella Waste Systems (CWST) 10-Q 5 May 17 2017 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2017	Apr. 28, 2017
Document Information [Line Items]
Entity Registrant Name	CASELLA WASTE SYSTEMS INC
Entity Central Index Key	911,177
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q1
Amendment Flag	false
Trading Symbol	CWST
Class A Common Stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		40,891,927
Class B Common Stock
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		988,200

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
CURRENT ASSETS:
Cash and cash equivalents	$ 2,226	$ 2,544
Accounts receivable - trade, net of allowance for doubtful accounts $645 and $1,069, respectively	55,627	61,196
Refundable income taxes	618	654
Prepaid expenses	7,851	7,989
Inventory	5,338	4,915
Other current assets	1,075	1,290
Total current assets	72,735	78,588
Property, plant, and equipment, net of accumulated depreciation and amortization of $850,962 and $837,122, respectively	393,744	398,466
Goodwill	119,936	119,899
Intangible assets, net	7,472	7,696
Restricted assets	1,039	1,002
Cost method investments	12,333	12,333
Other non-current assets	13,990	13,528
Total assets	621,249	631,512
CURRENT LIABILITIES:
Current maturities of long-term debt and capital leases	4,669	4,686
Accounts payable	40,512	44,997
Accrued payroll and related expenses	4,610	12,505
Accrued interest	2,413	4,654
Current accrued capping, closure and post-closure costs	705	668
Other accrued liabilities	16,572	14,916
Total current liabilities	69,481	82,426
Long-term debt and capital leases, less current portion	503,743	503,961
Accrued capping, closure and post-closure costs, less current portion	44,897	43,539
Deferred income taxes	6,104	6,178
Other long-term liabilities	20,201	19,958
COMMITMENTS AND CONTINGENCIES
Casella Waste Systems, Inc. stockholders' deficit
Additional paid-in capital	350,046	348,434
Accumulated deficit	(373,532)	(373,308)
Accumulated other comprehensive loss	(86)	(68)
Total Casella Waste Systems, Inc. stockholders' deficit	(23,153)	(24,526)
Noncontrolling interests	(24)	(24)
Total stockholders' deficit	(23,177)	(24,550)
Total liabilities and stockholders' deficit	621,249	631,512
Class A Common Stock
Casella Waste Systems, Inc. stockholders' deficit
Common stock	409	406
Class B Common Stock
Casella Waste Systems, Inc. stockholders' deficit
Common stock	$ 10	$ 10

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) $ in Thousands	Mar. 31, 2017USD ($)Vote$ / sharesshares	Dec. 31, 2016USD ($)Vote$ / sharesshares
Accounts receivable - trade, allowance for doubtful accounts | $	$ 645	$ 1,069
Property, plant and equipment, accumulated depreciation and amortization | $	$ 850,962	$ 837,122
Class A Common Stock
Common stock, par value (in USD per share) | $ / shares	$ 0.01	$ 0.01
Common stock, authorized shares (in shares)	100,000,000	100,000,000
Common stock, issued shares (in shares)	40,892,000	40,572,000
Common stock, outstanding shares (in shares)	40,892,000	40,572,000
Class B Common Stock
Common stock, par value (in USD per share) | $ / shares	$ 0.01	$ 0.01
Common stock, authorized shares (in shares)	1,000,000	1,000,000
Common stock, issued shares (in shares)	988,000	988,000
Common stock, outstanding shares (in shares)	988,000	988,000
Common stock, votes (in votes per share) | Vote	10	10

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Statement [Abstract]
Revenues	$ 133,802	$ 125,432
Operating expenses:
Cost of operations	94,544	90,418
General and administration	18,845	18,587
Depreciation and amortization	13,849	14,453
Total operating expenses	127,238	123,458
Operating income	6,564	1,974
Other expense (income):
Interest income	(69)	(104)
Interest expense	6,450	10,030
Loss (gain) on debt extinguishment	472	(48)
Other income	(81)	(141)
Other expense, net	6,772	9,737
Loss before income taxes	(208)	(7,763)
Provision (benefit) for income taxes	16	(149)
Net loss	(224)	(7,614)
Less: Net loss attributable to noncontrolling interests	0	(6)
Net loss attributable to common stockholders	$ (224)	$ (7,608)
Basic and diluted earnings per share attributable to common stockholders:
Basic and diluted weighted average common shares outstanding (in shares)	41,584	40,996
Basic and diluted earnings per common share (in USD per share)	$ (0.01)	$ (0.19)

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
Net loss	$ (224)	$ (7,614)
Hedging activity:
Interest rate swap settlements	(44)	0
Interest rate swap amounts reclassified into interest expense	69	0
Unrealized loss resulting from changes in fair value of derivative instruments	(66)	0
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax	23	(83)
Other comprehensive loss	(18)	(83)
Income tax expense related to items of other comprehensive loss	0	0
Other comprehensive loss, net of tax	(18)	(83)
Comprehensive loss	(242)	(7,697)
Less: Comprehensive loss attributable to noncontrolling interests	0	(6)
Comprehensive loss attributable to common stockholders	$ (242)	$ (7,691)

CONSOLIDATED STATEMENT OF STOCK

CONSOLIDATED STATEMENT OF STOCKHOLDERS' DEFICIT (Unaudited) - 3 months ended Mar. 31, 2017 - USD ($) shares in Thousands, $ in Thousands	Total	Additional Paid-In Capital	Accumulated Deficit	Comprehensive Loss	Noncontrolling Interests	Class A Common Stock	Class A Common StockCommon Stock	Class B Common Stock	Class B Common StockCommon Stock
Beginning balance at Dec. 31, 2016	$ (24,550)	$ 348,434	$ (373,308)	$ (68)	$ (24)		$ 406		$ 10
Balance (in shares) at Dec. 31, 2016						40,572	40,572	988	988
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(224)		(224)		0
Other comprehensive loss	(18)			(18)
Issuances of Class A common stock	358	355					$ 3
Issuances of Class A common stock (in shares)							320
Stock-based compensation	1,257	1,257
Ending balance at Mar. 31, 2017	$ (23,177)	$ 350,046	$ (373,532)	$ (86)	$ (24)		$ 409		$ 10
Balance (in shares) at Mar. 31, 2017						40,892	40,892	988	988

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash Flows from Operating Activities:
Net loss	$ (224)	$ (7,614)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	13,849	14,453
Depletion of landfill operating lease obligations	1,764	1,950
Interest accretion on landfill and environmental remediation liabilities	965	886
Amortization of debt issuance costs and discount on long-term debt	646	1,040
Stock-based compensation	1,257	722
Gain on sale of property and equipment	(84)	(203)
Loss (gain) on debt extinguishment	472	(48)
Deferred income taxes	(74)	100
Changes in assets and liabilities, net of effects of acquisitions and divestitures:
Accounts receivable	5,569	7,133
Accounts payable	(4,485)	(6,112)
Prepaid expenses, inventories and other assets	(145)	(1,492)
Accrued expenses and other liabilities	(8,834)	(9,091)
Net cash provided by operating activities	10,676	1,724
Cash Flows from Investing Activities:
Acquisitions, net of cash acquired	(414)	0
Acquisition related additions to property, plant and equipment	(58)	0
Additions to property, plant and equipment	(8,634)	(9,848)
Payments on landfill operating lease contracts	(977)	(500)
Proceeds from sale of property and equipment	84	359
Net cash used in investing activities	(9,999)	(9,989)
Cash Flows from Financing Activities:
Proceeds from long-term borrowings	71,200	64,300
Principal payments on long-term debt	(71,933)	(57,948)
Payments of debt issuance costs	(620)	(99)
Proceeds from the exercise of share based awards	358	0
Change in restricted cash	0	1,348
Net cash (used in) provided by financing activities	(995)	7,601
Net decrease in cash and cash equivalents	(318)	(664)
Cash and cash equivalents, beginning of period	2,544	2,312
Cash and cash equivalents, end of period	2,226	1,648
Cash paid during the period for:
Interest	8,045	16,122
Income taxes, net of refunds	$ 54	$ 101

BASIS OF PRESENTATION

BASIS OF PRESENTATION	3 Months Ended
	Mar. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
BASIS OF PRESENTATION	BASIS OF PRESENTATION Casella Waste Systems, Inc. (“Parent”), and its consolidated subsidiaries (collectively, “we”, “us” or “our”), is a regional, vertically integrated solid waste services company that provides collection, transfer, disposal, landfill, landfill gas-to-energy, recycling and organics services in the northeastern United States. We market recyclable metals, aluminum, plastics, paper and corrugated cardboard, which have been processed at our recycling facilities, as well as recyclables purchased from third-parties. We manage our solid waste operations on a geographic basis through two regional operating segments, the Eastern and Western regions, each of which provides a full range of solid waste services, and our larger-scale recycling and commodity brokerage operations through our Recycling segment. Organics services, ancillary operations, major account and industrial services, discontinued operations and earnings from equity method investees, as applicable, are included in our Other segment. The accompanying unaudited consolidated financial statements, which include the accounts of the Parent, our wholly-owned subsidiaries and any partially owned entities over which we have a controlling financial interest, have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). All significant intercompany accounts and transactions are eliminated in consolidation. Investments in entities in which we do not have a controlling financial interest are accounted for under either the equity method or the cost method of accounting, as appropriate. Our significant accounting policies are more fully discussed in Item 8 of our Annual Report on Form 10-K for the fiscal year ended December 31, 2016 , which was filed with the SEC on March 2, 2017. Preparation of our consolidated financial statements in accordance with GAAP requires management to make certain estimates and assumptions. These estimates and assumptions affect the accounting for and recognition and disclosure of assets, liabilities, equity, revenues and expenses. We must make these estimates and assumptions because certain information that we use is dependent on future events, cannot be calculated with a high degree of precision given the available data, or simply cannot be readily calculated. In the opinion of management, these consolidated financial statements include all adjustments, which include normal recurring and nonrecurring adjustments, necessary for a fair presentation of the financial position, results of operations and cash flows for the periods presented. The results for the three months ended March 31, 2017 may not be indicative of the results for any other interim period or the entire fiscal year. The consolidated financial statements presented herein should be read in conjunction with our audited consolidated financial statements included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2016 . Subsequent Events We have evaluated subsequent events or transactions that have occurred after the consolidated balance sheet date of March 31, 2017 through the date of filing of the consolidated financial statements with the SEC on this Quarterly Report on Form 10-Q. We have determined that, except as disclosed, there are no subsequent events that require disclosure in this Quarterly Report on Form 10-Q.

ACCOUNTING CHANGES

ACCOUNTING CHANGES	3 Months Ended
	Mar. 31, 2017
Accounting Changes and Error Corrections [Abstract]
ACCOUNTING CHANGES	ACCOUNTING CHANGES A table providing a brief description of recent Accounting Standards Updates (“ASU”) to the Accounting Standards Codification (“ASC”) issued by the Financial Accounting Standards Board (“FASB”) that may have a material effect on our consolidated financial statements upon adoption follows: Standard Description Effect on the Financial Statements or Other Significant Matters Accounting standards that are pending adoption ASU 2017-04: Intangibles - Goodwill and Other (Topic 350) Requires that when an entity is performing its annual, or interim, goodwill impairment test, it should compare the fair value of the reporting unit with its carrying amount when calculating its impairment charge, noting that the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. Additionally, if applicable, an entity should consider income tax effects from any tax deductible goodwill on the carrying amount of the reporting unit when calculating its impairment charge. As of December 31, 2016, we did not record a goodwill impairment charge related to our annual goodwill impairment test. Furthermore, at that time the fair value of each reporting unit exceeded its respective carrying value. If the carrying value of any of these reporting units exceeds the fair value when we perform a goodwill impairment test, we would record an impairment change equal to the amount by which the carrying value exceeds its fair value. This guidance is effective January 1, 2020 with early adoption permitted for interim or annual goodwill impairment tests performed after January 1, 2017. ASU 2016-02: Leases (Topic 842) Requires that a lessee recognize at the commencement date: a lease liability, which is the obligation of the lessee to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. We are currently assessing the provisions of this guidance and evaluating the timing and impact the guidance will have on our consolidated financial statements and related disclosures. We are also in the process of aggregating operating lease documentation for review. The adoption of this ASU primarily impacts the balance sheet through the recognition of a right-of-use asset and a lease liability for all leases with terms in excess of 12 months and currently classified as operating leases. This guidance is effective January 1, 2019 using a modified retrospective transition approach with early adoption permitted. ASU 2016-01: Financial Instruments - Overall (Topic 825-10) Requires the following: (1) equity investments (except those accounted for under the equity method of accounting, or those that result in consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income; (2) entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes; (3) separate presentation of financial assets and financial liabilities by measurement category and form of financial asset; and (4) the elimination of the disclosure requirement to disclose the method(s) and significant assumptions used to estimate the fair value that is required to be disclosed for financial instruments measured at amortized cost. The adoption of this guidance results in a cumulative-effect adjustment to the balance sheet, the recognition of changes in fair value of certain equity investments in net income, and enhanced disclosure. This guidance is effective January 1, 2018 with a cumulative-effect adjustment. ASU 2014-09, ASU 2015-14, ASU 2016-06, ASU 2016-10, ASU 2016-12 and ASU 2016-20: Revenue from Contracts with Customers (Topic 606) The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. We are currently evaluating the alternative methods of adoption and the effect of this guidance on our consolidated financial statements and related disclosures. To assess the impact of this standard, our internal resources have reviewed the amended guidance and attended training to assist with interpretation of the amended guidance. We are also in the process of identifying material contracts and revenue streams that are impacted by this guidance. This guidance is effective January 1, 2018 using a full or modified retrospective approach with early adoption permitted January 1, 2017.

BUSINESS COMBINATIONS

BUSINESS COMBINATIONS	3 Months Ended
	Mar. 31, 2017
Business Combinations [Abstract]
BUSINESS COMBINATIONS	BUSINESS COMBINATIONS We acquired one solid waste collection business in our Western region during the three months ended March 31, 2017 . The operating results of the acquired business are included in the accompanying unaudited consolidated statements of operations from the date of acquisition, and the purchase price has been allocated to the net assets acquired based on fair values at the date of the acquisition, with the residual amount recorded as goodwill. A summary of the purchase price for this acquisition and the allocation of the purchase price for this acquisition follows: Three Months Ended 2017 2016 Purchase Price: Cash paid for acquisitions $ 414 $ — Holdback 46 — Total 460 — Allocated as follows: Equipment 170 — Intangible assets 262 — Other liabilities, net (9 ) — Fair value of assets acquired and liabilities assumed 423 — Excess purchase price allocated to goodwill $ 37 $ — We also acquired three transfer stations in our Western region during the quarter ended June 30, 2016 whose operating results are included in the accompanying unaudited consolidated statements of operations from the date of acquisition. Unaudited pro forma combined information that shows our operational results as though each acquisition completed since the beginning of the prior fiscal year had occurred as of January 1, 2016 follows: Three Months Ended 2017 2016 Revenue $ 133,916 $ 126,426 Operating income $ 6,577 $ 1,914 Net loss attributable to common stockholders $ (217 ) $ (7,645 ) Basic earnings per share attributable to common stockholders $ (0.01 ) $ (0.19 ) Basic weighted average common shares outstanding 41,584 40,996 The pro forma results set forth in the table above have been prepared for comparative purposes only and are not necessarily indicative of the actual results of operations had the acquisitions occurred as of January 1, 2016 or of the results of our future operations. Furthermore, the pro forma results do not give effect to all cost savings or incremental costs that may occur as a result of the integration and consolidation of the completed acquisitions.

GOODWILL AND INTANGIBLE ASSETS

GOODWILL AND INTANGIBLE ASSETS	3 Months Ended
	Mar. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND INTANGIBLE ASSETS	GOODWILL AND INTANGIBLE ASSETS A summary of the activity and balances related to goodwill by operating segment follows: December 31, 2016 Acquisitions March 31, 2017 Eastern region $ 17,429 $ — $ 17,429 Western region 88,426 37 88,463 Recycling 12,315 — 12,315 Other 1,729 — 1,729 Total $ 119,899 $ 37 $ 119,936 A summary of intangible assets by intangible asset type follows: Covenants Not-to-Compete Client Lists Total Balance, March 31, 2017 Intangible assets $ 17,624 $ 16,304 $ 33,928 Less accumulated amortization (16,517 ) (9,939 ) (26,456 ) $ 1,107 $ 6,365 $ 7,472 Covenants Not-to-Compete Client Lists Total Balance, December 31, 2016 Intangible assets $ 17,594 $ 16,071 $ 33,665 Less accumulated amortization (16,402 ) (9,567 ) (25,969 ) $ 1,192 $ 6,504 $ 7,696 Intangible amortization expense was $487 during the three months ended March 31, 2017 , as compared to $524 during the three months ended March 31, 2016 . A summary of intangible amortization expense estimated for the five fiscal years following the fiscal year ended December 31, 2016 and thereafter follows: Estimated Future Amortization Expense as of March 31, 2017 Fiscal year ending December 31, 2017 $ 1,455 Fiscal year ending December 31, 2018 $ 1,741 Fiscal year ending December 31, 2019 $ 1,366 Fiscal year ending December 31, 2020 $ 1,168 Fiscal year ending December 31, 2021 $ 910 Thereafter $ 832

ACCRUED FINAL CAPPING, CLOSURE

ACCRUED FINAL CAPPING, CLOSURE AND POST CLOSURE	3 Months Ended
	Mar. 31, 2017
Asset Retirement Obligation Disclosure [Abstract]
ACCRUED FINAL CAPPING, CLOSURE AND POST CLOSURE	ACCRUED FINAL CAPPING, CLOSURE AND POST CLOSURE Accrued final capping, closure and post-closure costs include the current and non-current portion of costs associated with obligations for final capping, closure and post-closure of our landfills. We estimate our future final capping, closure and post-closure costs in order to determine the final capping, closure and post-closure expense per ton of waste placed into each landfill. The anticipated time frame for paying these costs varies based on the remaining useful life of each landfill, as well as the duration of the post-closure monitoring period. A summary of the changes to accrued final capping, closure and post-closure liabilities follows: Three Months Ended 2017 2016 Beginning balance $ 44,207 $ 41,041 Obligations incurred 556 526 Accretion expense 965 886 Obligations settled (1) (126 ) (198 ) Ending balance $ 45,602 $ 42,255 (1) Includes amounts that are being processed through accounts payable as a part of our disbursement cycle.

LONG-TERM DEBT

LONG-TERM DEBT	3 Months Ended
	Mar. 31, 2017
Debt Disclosure [Abstract]
LONG-TERM DEBT	LONG-TERM DEBT A summary of long-term debt and capital leases by debt instrument follows: March 31, December 31, Senior Secured Credit Facility: Revolving Credit Facility due October 2021; bearing interest at LIBOR plus 2.75% and 3.00%, respectively $ 63,000 $ 62,600 Term Loan B Facility due October 2023; bearing interest at LIBOR plus 3.00% 349,125 350,000 Tax-Exempt Bonds: New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014 due December 2044 - fixed rate interest period through 2019; bearing interest at 3.75% 25,000 25,000 New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014R-2 due December 2044 - fixed rate interest period through 2026; bearing interest at 3.125% 15,000 15,000 Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-3 due January 2025 - fixed rate interest period through 2025; bearing interest at 5.25% 25,000 — Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2015 due August 2035 - fixed rate interest period through 2025; bearing interest at 5.125% 15,000 15,000 Vermont Economic Development Authority Solid Waste Disposal Long-Term Revenue Bonds Series 2013 due April 2036 - fixed rate interest period through 2018; bearing interest at 4.75% 16,000 16,000 Business Finance Authority of the State of New Hampshire Solid Waste Disposal Revenue Bonds Series 2013 due April 2029 - fixed rate interest period through 2019; bearing interest at 4.00% 11,000 11,000 Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-2 due January 2025 - fixed rate interest period through 2017; bore interest at 6.25% — 21,400 Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-1; letter of credit backed due January 2025 - bore interest at SIFMA Index — 3,600 Other: Capital leases maturing through April 2023; bearing interest at up to 7.70% 5,318 5,534 Notes payable maturing through January 2021; bearing interest at up to 7.00% 407 449 Principal amount of long-term debt and capital leases 524,850 525,583 Less—unamortized discount and debt issuance costs (1) 16,438 16,936 Long-term debt and capital leases less unamortized discount and debt issuance costs 508,412 508,647 Less—current maturities of long-term debt 4,669 4,686 $ 503,743 $ 503,961 (1) A summary of unamortized discount and debt issuance costs by debt instrument follows: March 31, December 31, Revolving Credit Facility $ 4,709 $ 4,965 Term Loan B Facility (including unamortized discount of $1,655 and $1,712) 7,462 7,718 New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014 1,174 1,221 New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014R-2 556 571 Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-3 666 — Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2015 743 760 Vermont Economic Development Authority Solid Waste Disposal Long-Term Revenue Bonds Series 2013 597 605 Business Finance Authority of the State of New Hampshire Solid Waste Disposal Revenue Bonds Series 2013 531 563 Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-1 — 31 Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-2 — 502 $ 16,438 $ 16,936 Financing Activities Term Loan B Facility In April 2017, we entered into the first amendment (“Repricing Amendment”) to our $350,000 aggregate principal amount term loan B facility ("Term Loan B Facility") and $160,000 revolving line of credit facility (“Revolving Credit Facility” and, together with the Term Loan B Facility, the "Credit Facility"). The Repricing Amendment decreased the applicable interest margin for our Term Loan B Facility by 25 basis points for both LIBOR borrowings and base rate borrowings. The applicable interest rate margin will continue to be determined based on our consolidated net leverage ratio, with the interest currently set at 2.75% for LIBOR borrowings (with a 1.00% LIBOR floor), and 1.75% for base rate borrowings. The applicable interest rate will be reduced to 2.50% for LIBOR borrowings (with a 1.00% LIBOR floor), and 1.50% for base rate borrowings upon us reaching a consolidated net leverage ratio of 3.75 x or less. Maine Bonds In the three months ended March 31, 2017, we completed the remarketing of $3,600 aggregate principal amount of Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-1 (“FAME Bonds 2005R-1”) and $21,400 aggregate principal amount of Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-2 (“FAME Bonds 2005R-2”) into one series of $25,000 aggregate principal amount Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-3 (“FAME Bonds 2005R-3”). The FAME Bonds 2005R-3, which are unsecured and guaranteed jointly and severally, fully and unconditionally by all of our significant wholly-owned subsidiaries, accrue interest at 5.25% per annum until they mature on January 1, 2025. Loss on Debt Extinguishment We recorded a loss on debt extinguishment of $472 in the three months ended March 31, 2017 , as compared to a gain on debt extinguishment of $(48) during the three months ended March 31, 2016 , associated with the following: • the write-off of debt issuance costs in connection with the remarketing of the FAME Bonds 2005R-1 and the FAME Bonds 2005R-2 into the FAME Bonds 2005R-3 in the three months ended March 31, 2017; and • the below par repurchase price, net of the write off of debt issuance costs and unamortized original issue discount in proportion with the settlement amount, associated with the early retirement of a portion of our 7.75% senior subordinated notes due February 2019 in the three months ended March 31, 2016. Cash Flow Hedges In the three months ended March 31, 2017 , we entered into three interest rate derivative agreements to hedge interest rate risk associated with the variable rate portion of our long-term debt. The total notional amount of these agreements is $60,000 and requires us to receive interest based on changes in the 1-month LIBOR index with a 1.0% floor and pay interest at a weighted average rate of approximately 1.95% . Two of the agreements, with a total notional amount of $35,000 , mature in February 2021, and the final agreement, with a total notional amount of $25,000 , matures in February 2022. We have designated these derivative instruments as cash flow hedges. In accordance with the derivatives and hedging guidance in FASB ASC 815 - Derivatives and Hedging, the effective portions of the changes in fair values of interest rate swaps have been recorded in equity as a component of accumulated other comprehensive loss, net of tax. As the critical terms of the interest rate swaps match the underlying debt being hedged, no ineffectiveness is recognized on these swaps and, therefore, all unrealized changes in fair value are recorded in accumulated other comprehensive loss, net of tax. Amounts are reclassified from accumulated other comprehensive loss, net of tax into earnings in the same period or periods during which the hedged transaction effects earnings. As of March 31, 2017 , we have recorded a derivative asset with a fair value of $388 in other non-current assets and a derivative liability with a fair value of $454 in other accrued liabilities associated with these cash flow hedges.

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Legal Proceedings In the ordinary course of our business and as a result of the extensive governmental regulation of the solid waste industry, we are subject to various judicial and administrative proceedings involving state and local agencies. In these proceedings, an agency may seek to impose fines or to revoke or deny renewal of an operating permit held by us. From time to time, we may also be subject to actions brought by special interest or other groups, adjacent landowners or residents in connection with the permitting and licensing of landfills and transfer stations, or allegations of environmental damage or violations of the permits and licenses pursuant to which we operate. In addition, we may be named defendants in various claims and suits pending for alleged damages to persons and property, alleged violations of certain laws and alleged liabilities arising out of matters occurring during the ordinary operation of a waste management business. In accordance with FASB ASC 450 - Contingencies, we accrue for legal proceedings, inclusive of legal costs, when losses become probable and reasonably estimable. As of the end of each applicable reporting period, we review each of our legal proceedings to determine whether it is probable, reasonably possible or remote that a liability has been incurred and, if it is at least reasonably possible, whether a range of loss can be reasonably estimated under the provisions of FASB ASC 450-20. In instances where we determine that a loss is probable and we can reasonably estimate a range of loss we may incur with respect to such a matter, we record an accrual for the amount within the range that constitutes our best estimate of the possible loss. If we are able to reasonably estimate a range, but no amount within the range appears to be a better estimate than any other, we record an accrual in the amount that is the low end of such range. When a loss is reasonably possible, but not probable, we will not record an accrual, but we will disclose our estimate of the possible range of loss where such estimate can be made in accordance with FASB ASC 450-20. Environmental Remediation Liability We are subject to liability for environmental damage, including personal injury and property damage, that our solid waste, recycling and power generation facilities may cause to neighboring property owners, particularly as a result of the contamination of drinking water sources or soil, possibly including damage resulting from conditions that existed before we acquired the facilities. We may also be subject to liability for similar claims arising from off-site environmental contamination caused by pollutants or hazardous substances if we or our predecessors arrange or arranged to transport, treat or dispose of those materials. The following matters represent our material outstanding claims. Southbridge Recycling & Disposal Park, Inc. In October 2015, our Southbridge Recycling and Disposal Park, Inc. (“SRD”) subsidiary reported to the Massachusetts Department of Environmental Protection (“MADEP”) results of analysis of samples collected pursuant to our existing permit from private drinking water wells located near the Town of Southbridge, Massachusetts (“Town”) Landfill (“Southbridge Landfill”), which is operated by SRD. Those results indicated the presence of contaminants above the levels triggering notice and response obligations under MADEP regulations. In response to those results, we are carrying out an Immediate Response Action pursuant to Massachusetts General Law Chapter 21E (the "Charlton 21E Obligations") pursuant to state law. Further, we have implemented a plan to analyze and better understand the groundwater near the Southbridge Landfill and we are investigating with the objective of identifying the source or sources of the elevated levels of contamination measured in the well samples. If it is determined that some or all of the contamination originated at the Southbridge Landfill, we will work with the Town, the Southbridge Landfill owner and the former operator of an unlined portion of the Southbridge Landfill, which was used prior to our operation of a double-lined portion of the Southbridge Landfill commencing in 2004, to evaluate and allocate the liabilities related to the Charlton 21E Obligations. In July 2016, we sent correspondence to the Town pursuant to Chapter 21E of Massachusetts General Laws ("Chapter 21E") demanding that the Town reimburse us for the environmental response costs we had spent and that the Town be responsible for all such costs in the future, as well as any other costs or liabilities resulting from the release of contaminants from the unlined portion of the Southbridge Landfill. The Town responded in September 2016, denying that the Southbridge Landfill is the source of such contamination, and claiming that if it is, that we may owe an indemnity to the Town pursuant to the Operating Agreement between us and the Town dated May 29, 2007, as amended. As of March 31, 2017 , we have incurred total costs of approximately $2,809 . We entered into a Tolling Agreement with the Town to delay any further administrative or legal actions until our work with MADEP more specifically defines the parties’ responsibilities for the Charlton 21E Obligations, if any. Please see below for further discussion of our relationship with the Town regarding the Charlton 21E Obligations. In February 2016, we and the Town received a Notice of Intent to Sue under the Resource Conservation and Recovery Act ("RCRA") from a law firm purporting to represent residents proximate to the Southbridge Landfill, indicating its intent to file suit against us alleging the groundwater contamination originated from the Southbridge Landfill. In February 2017, we received an additional Notice of Intent to Sue from the National Environmental Law Center under the Federal Clean Water Act ("CWA") and RCRA (the “Acts”) on behalf of Environment America, Inc., d/b/a Environment Massachusetts, and Toxics Action Center, Inc., which have referred to themselves as the Citizen Groups. The Citizen Groups allege that we have violated the Acts, and that they intend to seek appropriate relief in federal court for those alleged violations. We believe it is reasonably possible that a loss will occur as a result of these potential matters although an estimate of loss cannot be reasonably provided at this time. We believe the Town should be responsible for costs or liabilities associated with these possible suits relative to alleged contamination originating from the unlined portion of the Southbridge Landfill, although there can be no assurance that we will not be required to incur some or all of such costs and liabilities. While no suit has yet been filed against us or the Town related to the foregoing, we entered into an Administrative Consent Order on April 26, 2017 (the “ACO”), with MADEP, the Town, and the Town of Charlton, committing us to equally share the costs with MADEP, of up to $10,000 ( $5,000 each) for the Town to install a municipal waterline in the Town of Charlton ("Waterline"). Upon satisfactory completion of that Waterline, and other matters covered by the ACO, we and the Town will be released by MADEP from any future responsibilities for the Charlton Chapter 21E Obligations. We also entered into an agreement with the Town on April 28, 2017 entitled the “21E Settlement and Water System Construction Funding Agreement” (the “Waterline Agreement”), wherein we and the Town released each other from claims arising from the Charlton 21E Obligations. Pursuant to the Waterline Agreement, the Town will issue a twenty ( 20 ) year bond for our portion of the Waterline costs (up to $5,000 ). We have agreed to reimburse the Town for periodic payments under such bond. In August 2016, we filed a complaint against Steadfast Insurance Company (“Steadfast”) in the Superior Court of Suffolk County, Massachusetts, alleging among other things, that Steadfast breached its Pollution Liability Policy (“Policy”) purchased by us in April 2015, by refusing to acknowledge coverage under the Policy, and refusing to cover any of the costs and liabilities incurred by us as described above as well as costs and liabilities that we may incur in the future. Steadfast filed an answer and counterclaim in September 2016, denying that it has any obligations to us under the Policy, and seeking declaratory judgment of Steadfast’s obligations under the Policy. We are in the discovery phase of this litigation. The costs and liabilities we may be required to incur in connection with the foregoing could be material to our results of operations, our cash flows and our financial condition. We are continuing to pursue development of the Southbridge Landfill, and we believe that the commitments that we have undertaken in the ACO are specifically in furtherance of the development of limited short-term expansion of the Southbridge Landfill and our efforts to develop longer-term new landfill capacity in the Town. We believe that our commitments in the ACO will allow us to continue to develop good faith relationships with MADEP, the Town, and abutting communities. Nevertheless, we are carefully evaluating the impact and potential impact of the foregoing matters, together with estimated future costs associated with the permitting, engineering and construction activities for the planned expansion of the Southbridge Landfill, and any potential future landfill, against the possible outcomes of the permitting process and the anticipated future benefits of successful expansions. It is possible that based on these ongoing anlyses we may conclude that closing the Southbridge Landfill and/or terminating our development efforts, is in our best economic interest. While no conclusions have been reached at this time and we continue to be committed to the expansion process, we are acting to prudently manage waste volumes into the Southbridge Landfill to prolong the useful life of the Southbridge Landfill in the event we are unsuccessful in obtaining the expansion permits or choose to modify or withdraw our permit application due to our estimate of the economic benefit of the expansion relative to costs. Potsdam Environmental Remediation Liability On December 20, 2000, the State of New York Department of Environmental Conservation (“DEC”) issued an Order on Consent (“Order”) which named Waste-Stream, Inc. (“WSI”), our subsidiary, General Motors Corporation (“GM”) and Niagara Mohawk Power Corporation (“NiMo”) as Respondents. The Order required that the Respondents undertake certain work on a 25 -acre scrap yard and solid waste transfer station owned by WSI in Potsdam, New York, including the preparation of a Remedial Investigation and Feasibility Study (“Study”). A draft of the Study was submitted to the DEC in January 2009 (followed by a final report in May 2009). The Study estimated that the undiscounted costs associated with implementing the preferred remedies would be approximately $10,219 . On February 28, 2011, the DEC issued a Proposed Remedial Action Plan for the site and accepted public comments on the proposed remedy through March 29, 2011. We submitted comments to the DEC on this matter. In April 2011, the DEC issued the final Record of Decision (“ROD”) for the site. The ROD was subsequently rescinded by the DEC for failure to respond to all submitted comments. The preliminary ROD, however, estimated that the present cost associated with implementing the preferred remedies would be approximately $12,130 . The DEC issued the final ROD in June 2011 with proposed remedies consistent with its earlier ROD. An Order on Consent and Administrative Settlement naming WSI and NiMo as Respondents was executed by the Respondents and DEC with an effective date of October 25, 2013. On January 29, 2016, a Cost-Sharing Agreement was executed between WSI, NiMo, Alcoa Inc. (“Alcoa”) and Reynolds Metal Company (“Reynolds”) whereby Alcoa and Reynolds elected to voluntarily participate in the onsite remediation activities at a 15% participant share. It is unlikely that any significant expenditures relating to onsite remediation will be incurred until the fiscal year ending December 31, 2018. WSI is jointly and severally liable with NiMo, Alcoa and Reynolds for the total cost to remediate. We have recorded an environmental remediation liability associated with the Potsdam site based on incurred costs to date and estimated costs to complete the remediation in other accrued liabilities and other long-term liabilities. Our expenditures could be significantly higher if costs exceed estimates. We inflate the estimated costs in current dollars to the expected time of payment and discount the total cost to present value using a risk free interest rate of 1.5% . The environmental remediation liability associated with the Potsdam site as of each of March 31, 2017 and December 31, 2016 is $5,866 .

STOCKHOLDERS' EQUITY

STOCKHOLDERS' EQUITY	3 Months Ended
	Mar. 31, 2017
Equity [Abstract]
STOCKHOLDERS' EQUITY	STOCKHOLDERS' EQUITY Stock Based Compensation Shares Available For Issuance In the fiscal year ended December 31, 2016, we adopted the 2016 Incentive Plan (“2016 Plan”). Under the 2016 Plan, we may grant awards up to an aggregate amount of shares equal to the sum of: (i) 2,250 shares of Class A common stock (subject to adjustment in the event of stock splits and other similar events), plus (ii) such additional number of shares of Class A common stock (up to 2,723 shares) as is equal to the sum of the number of shares of Class A common stock that remained available for grant under the 2006 Stock Incentive Plan (“2006 Plan”) immediately prior to the expiration of the 2006 Plan and the number of shares of Class A common stock subject to awards granted under the 2006 Plan that expire, terminate or are otherwise surrendered, canceled, forfeited or repurchased by us. As of March 31, 2017 , there were 1,927 Class A common stock equivalents available for future grant under the 2016 Plan. Stock Options Stock options are granted at a price equal to the prevailing fair value of our Class A common stock at the date of grant. Generally, stock options granted have a term not to exceed ten years and vest over a one year to four year period from the date of grant. The fair value of each stock option granted, with the exception of market-based performance stock option grants, is estimated using a Black-Scholes option-pricing model, which requires extensive use of accounting judgment and financial estimation, including estimates of the expected term stock option holders will retain their vested stock options before exercising them and the estimated volatility of our Class A common stock price over the expected term. The fair value of each market-based performance stock option granted is estimated using a Monte Carlo option-pricing model, which also requires extensive use of accounting judgment and financial estimation, including estimates of the expected term stock option holders will retain their vested stock options before exercising them and the estimated volatility of our Class A common stock price over the expected term, but also including estimates of share price appreciation plus the value of dividends of our Class A common stock as compared to the Russell 2000 Index over the requisite service period. A summary of stock option activity follows: Stock Options (1) Weighted Average Exercise Price Weighted Average Remaining Contractual Term (years) Aggregate Intrinsic Value Outstanding, December 31, 2016 1,115 $ 6.13 Granted — $ — Exercised (33 ) $ 11.01 Forfeited (2 ) $ 4.06 Outstanding, March 31, 2017 1,080 $ 5.98 5.7 $ 8,787 Exercisable, March 31, 2017 747 $ 5.51 4.5 $ 6,431 Unvested, March 31, 2017 373 $ 7.62 8.4 $ 2,421 (1) Market-based performance stock options are included at the 100% attainment level. Attainment of the maximum performance targets and market achievements would result in the issuance of an additional 40 shares of Class A common stock currently included in unvested. Stock-based compensation expense for stock options was $171 during the three months ended March 31, 2017 , as compared to $146 during the three months ended March 31, 2016 . During the three months ended March 31, 2017 , the aggregate intrinsic value of stock options exercised was $53 . As of March 31, 2017 , total unrecognized stock-based compensation expense related to outstanding stock options, including market-based performance stock options assuming the attainment of maximum performance targets, was $947 , which will be recognized over a weighted average period of 1.0 year. Other Stock Awards Restricted stock awards, restricted stock units and performance stock units, with the exception of market-based performance stock units, are granted at a price equal to the fair value of our Class A common stock at the date of grant. The fair value of each market-based performance stock unit is estimated using a Monte Carlo pricing model, which requires extensive use of accounting judgment and financial estimation, including the estimated share price appreciation plus the value of dividends of our Class A common stock as compared to the Russell 2000 Index over the requisite service period. Restricted stock awards granted to non-employee directors vest incrementally over a three year period beginning on the first anniversary of the date of grant. Restricted stock units vest incrementally over an identified service period beginning on the grant date based on continued employment. Performance stock units, including market-based performance stock units, vest at a future date following the grant date and are based on the attainment of performance targets and market achievements, as applicable. A summary of restricted stock, restricted stock unit and performance stock unit activity follows: Restricted Stock, Restricted Stock Units, and Performance Stock Units (1) Weighted Average Exercise Price Weighted Average Remaining Contractual Term (years) Aggregate Intrinsic Value Outstanding, December 31, 2016 1,099 $ 7.03 Granted 407 $ 12.13 Class A Common Stock Vested (288 ) $ 5.01 Forfeited (17 ) $ 5.94 Outstanding, March 31, 2017 1,201 $ 9.20 1.9 $ 5,936 Unvested, March 31, 2017 1,563 $ 9.97 2.0 $ 6,539 (1) Market-based performance stock unit grants are included at the 100% attainment level. Attainment of the maximum performance targets and market achievements would result in the issuance of an additional 362 shares of Class A common stock currently included in unvested. Stock-based compensation expense related to restricted stock, restricted stock units and performance stock units was $1,058 during the three months ended March 31, 2017 , as compared to $550 during the three months ended March 31, 2016 . During the three months ended March 31, 2017 , the total fair value of other stock awards vested was $3,408 . As of March 31, 2017 , total unrecognized stock-based compensation expense related to outstanding restricted stock and restricted stock units was $4,704 , which will be recognized over a weighted average period of 1.7 years. As of March 31, 2017 , maximum unrecognized stock-based compensation expense related to outstanding performance stock units, assuming the attainment of maximum performance targets, was $7,700 to be recognized over a weighted average period of 2.2 years. The weighted average fair value of market-based performance stock units granted during the three months ended March 31, 2017 was $12.51 per award, which was calculated using a Monte Carlo pricing model assuming a risk free interest rate of 1.45% and an expected volatility of 32.80% assuming no expected dividend yield. The risk-free interest rate is based on the U.S. Treasury yield curve for the expected service period of the award. Expected volatility is calculated using the daily volatility of our Class A common stock over the expected service period of the award. The Monte Carlo pricing model requires extensive use of accounting judgment and financial estimation. Application of alternative assumptions could produce significantly different estimates of the fair value of stock-based compensation and consequently, the related amounts recognized in the consolidated statements of operations. We also recorded $28 of stock-based compensation expense related to our Amended and Restated 1997 Employee Stock Purchase Plan during the three months ended March 31, 2017 , as compared to $26 during the three months ended March 31, 2016 . Comprehensive Loss A summary of the changes in the balances of each component of accumulated other comprehensive loss , net of tax follows: Marketable Securities Interest Rate Swaps Balance, December 31, 2016 $ (68 ) $ — Other comprehensive income (loss) before reclassifications 23 (110 ) Amounts reclassified from accumulated other comprehensive income (loss) — 69 Net current-period other comprehensive income (loss) 23 (41 ) Balance, March 31, 2017 $ (45 ) $ (41 ) A summary of reclassifications out of accumulated other comprehensive loss , net of tax follows: Three Months Ended 2017 2016 Details About Accumulated Other Comprehensive Loss Components Amounts Reclassified Out of Accumulated Other Comprehensive Loss Affected Line Item in the Consolidated Statements of Operations Interest rate swaps 69 — Interest expense 69 — Loss before income taxes — — Provision (benefit) for income taxes $ 69 $ — Net loss

EARNINGS PER SHARE

EARNINGS PER SHARE	3 Months Ended
	Mar. 31, 2017
Earnings Per Share [Abstract]
EARNINGS PER SHARE	EARNINGS PER SHARE A summary of the numerator and denominators used in the computation of earnings per share follows: Three Months Ended 2017 2016 Numerator: Net loss attributable to common stockholders $ (224 ) $ (7,608 ) Denominators: Number of shares outstanding, end of period: Class A common stock 40,892 40,243 Class B common stock 988 988 Unvested restricted stock (88 ) (115 ) Effect of weighted average shares outstanding (208 ) (120 ) Basic and diluted weighted average common shares outstanding 41,584 40,996 Anti-dilutive potentially issuable shares 2,683 2,445

FAIR VALUE OF FINANCIAL INSTRUM

FAIR VALUE OF FINANCIAL INSTRUMENTS	3 Months Ended
	Mar. 31, 2017
Fair Value Disclosures [Abstract]
FAIR VALUE OF FINANCIAL INSTRUMENTS	FAIR VALUE OF FINANCIAL INSTRUMENTS We use a three-tier fair value hierarchy to classify and disclose all assets and liabilities measured at fair value on a recurring basis, as well as assets and liabilities measured at fair value on a non-recurring basis, in periods subsequent to their initial measurement. These tiers include: Level 1, defined as quoted market prices in active markets for identical assets or liabilities; Level 2, defined as inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; and Level 3, defined as unobservable inputs that are not corroborated by market data. We use valuation techniques that maximize the use of market prices and observable inputs and minimize the use of unobservable inputs. In measuring the fair value of our financial assets and liabilities, we rely on market data or assumptions that we believe market participants would use in pricing an asset or a liability. Assets and Liabilities Accounted for at Fair Value Our financial instruments include cash and cash equivalents, accounts receivable-trade, restricted cash and investments held in trust on deposit with various banks as collateral for our obligations relative to our landfill final capping, closure and post-closure costs, interest rate derivatives, trade payables and long-term debt. The carrying values of cash and cash equivalents, accounts receivable - trade and trade payables approximate their respective fair values due to their short-term nature. The fair value of restricted cash and investments held in trust, which are valued using quoted market prices, are included as restricted assets in the Level 1 tier below. The fair value of the interest rate derivatives included in the Level 2 tier below was calculated using discounted cash flow valuation methodologies based upon the one month LIBOR yield curves that are observable at commonly quoted intervals for the full term of the swaps. Summaries of our financial assets and liabilities that are measured at fair value on a recurring basis follow: Fair Value Measurement at March 31, 2017 Using: Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Interest rate derivatives $ — $ 388 $ — Restricted investments - landfill closure 1,039 — — Total $ 1,039 $ 388 $ — Liabilities: Interest rate derivatives $ — $ 454 $ — Fair Value Measurement at December 31, 2016 Using: Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Restricted investments - landfill closure $ 1,002 $ — $ — Fair Value of Debt As of March 31, 2017 , the fair value of our fixed rate debt, including our FAME Bonds 2005R-3, Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2015 (“FAME Bonds 2015”), Vermont Economic Development Authority Solid Waste Disposal Long-Term Revenue Bonds Series 2013 (“Vermont Bonds”), New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014 (“New York Bonds 2014”), New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014R-2 (“New York Bonds 2016”) and Solid Waste Disposal Revenue Bonds Series 2013 issued by the Business Finance Authority of the State of New Hampshire (“New Hampshire Bonds”) was approximately $104,308 and the carrying value was $107,000 . The fair value of the FAME Bonds 2005R-3, the FAME Bonds 2015, the Vermont Bonds, the New York Bonds 2014, the New York Bonds 2016 and the New Hampshire Bonds is considered to be Level 2 within the fair value hierarchy as the fair value is determined using market approach pricing provided by a third-party that utilizes pricing models and pricing systems, mathematical tools and judgment to determine the evaluated price for the security based on the market information of each of the bonds or securities with similar characteristics. As of March 31, 2017 , the fair value of our Term Loan B Facility was approximately $351,743 and the carrying value was $349,125 . The fair value of the Term Loan B Facility is considered to be Level 2 within the fair value hierarchy as its fair value is based off of quoted market prices in a principal to principal market with limited public information. As of March 31, 2017 , the fair value of our Revolving Credit Facility approximated its carrying value of $63,000 based on current borrowing rates for similar types of borrowing arrangements, or Level 2 inputs. Although we have determined the estimated fair value amounts of the Term Loan B Facility, FAME Bonds 2005R-3, FAME Bonds 2015, Vermont Bonds, New York Bonds 2014, New York Bonds 2016 and New Hampshire Bonds using available market information and commonly accepted valuation methodologies, a change in available market information, and/or the use of different assumptions and/or estimation methodologies could have a material effect on the estimated fair values. These amounts have not been revalued, and current estimates of fair value could differ significantly from the amounts presented.

SEGMENT REPORTING

SEGMENT REPORTING	3 Months Ended
	Mar. 31, 2017
Segment Reporting [Abstract]
SEGMENT REPORTING	SEGMENT REPORTING We report selected information about operating segments in a manner consistent with that used for internal management reporting. We classify our solid waste operations on a geographic basis through regional operating segments, our Western and Eastern regions. Revenues associated with our solid waste operations are derived mainly from solid waste collection and disposal, landfill, landfill gas-to-energy, transfer and recycling services in the northeastern United States. Our revenues in the Recycling segment are derived from municipalities and customers in the form of processing fees, tipping fees and commodity sales. Organics services, ancillary operations, major account and industrial services, discontinued operations, and earnings from equity method investees, as applicable, are included in our Other segment. Three Months Ended March 31, 2017 Segment Outside revenues Inter-company revenue Depreciation and amortization Operating income Total assets Eastern $ 38,686 $ 9,522 $ 5,404 $ 21 $ 197,817 Western 54,144 15,781 6,604 4,089 324,262 Recycling 16,635 (244 ) 1,004 1,583 50,138 Other 24,337 374 837 871 49,032 Eliminations — (25,433 ) — — — Total $ 133,802 $ — $ 13,849 $ 6,564 $ 621,249 Three Months Ended March 31, 2016 Segment Outside revenues Inter-company revenue Depreciation and amortization Operating income (loss) Total assets Eastern $ 38,987 $ 9,536 $ 6,190 $ (788 ) $ 209,315 Western 52,462 14,852 6,490 2,993 312,369 Recycling 10,638 631 1,092 (1,074 ) 48,042 Other 23,345 280 681 843 50,680 Eliminations — (25,299 ) — — — Total $ 125,432 $ — $ 14,453 $ 1,974 $ 620,406 A summary of our revenues attributable to services provided follows: Three Months Ended 2017 2016 Collection $ 59,838 $ 57,851 Disposal 31,281 32,253 Power generation 1,352 1,707 Processing 1,660 973 Solid waste operations 94,131 92,784 Organics 9,214 8,935 Customer solutions 13,822 13,075 Recycling 16,635 10,638 Total revenues $ 133,802 $ 125,432

ACCOUNTING CHANGES (Policies)

ACCOUNTING CHANGES (Policies)	3 Months Ended
	Mar. 31, 2017
Accounting Changes and Error Corrections [Abstract]
Basis of Presentation	Casella Waste Systems, Inc. (“Parent”), and its consolidated subsidiaries (collectively, “we”, “us” or “our”), is a regional, vertically integrated solid waste services company that provides collection, transfer, disposal, landfill, landfill gas-to-energy, recycling and organics services in the northeastern United States. We market recyclable metals, aluminum, plastics, paper and corrugated cardboard, which have been processed at our recycling facilities, as well as recyclables purchased from third-parties. We manage our solid waste operations on a geographic basis through two regional operating segments, the Eastern and Western regions, each of which provides a full range of solid waste services, and our larger-scale recycling and commodity brokerage operations through our Recycling segment. Organics services, ancillary operations, major account and industrial services, discontinued operations and earnings from equity method investees, as applicable, are included in our Other segment. The accompanying unaudited consolidated financial statements, which include the accounts of the Parent, our wholly-owned subsidiaries and any partially owned entities over which we have a controlling financial interest, have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). All significant intercompany accounts and transactions are eliminated in consolidation. Investments in entities in which we do not have a controlling financial interest are accounted for under either the equity method or the cost method of accounting, as appropriate. Our significant accounting policies are more fully discussed in Item 8 of our Annual Report on Form 10-K for the fiscal year ended December 31, 2016 , which was filed with the SEC on March 2, 2017.
Use of Estimates	Preparation of our consolidated financial statements in accordance with GAAP requires management to make certain estimates and assumptions. These estimates and assumptions affect the accounting for and recognition and disclosure of assets, liabilities, equity, revenues and expenses. We must make these estimates and assumptions because certain information that we use is dependent on future events, cannot be calculated with a high degree of precision given the available data, or simply cannot be readily calculated. In the opinion of management, these consolidated financial statements include all adjustments, which include normal recurring and nonrecurring adjustments, necessary for a fair presentation of the financial position, results of operations and cash flows for the periods presented. The results for the three months ended March 31, 2017 may not be indicative of the results for any other interim period or the entire fiscal year. The consolidated financial statements presented herein should be read in conjunction with our audited consolidated financial statements included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2016 .
Subsequent Events	We have evaluated subsequent events or transactions that have occurred after the consolidated balance sheet date of March 31, 2017 through the date of filing of the consolidated financial statements with the SEC on this Quarterly Report on Form 10-Q. We have determined that, except as disclosed, there are no subsequent events that require disclosure in this Quarterly Report on Form 10-Q.
Accounting standards that are not yet adopted	Standard Description Effect on the Financial Statements or Other Significant Matters Accounting standards that are pending adoption ASU 2017-04: Intangibles - Goodwill and Other (Topic 350) Requires that when an entity is performing its annual, or interim, goodwill impairment test, it should compare the fair value of the reporting unit with its carrying amount when calculating its impairment charge, noting that the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. Additionally, if applicable, an entity should consider income tax effects from any tax deductible goodwill on the carrying amount of the reporting unit when calculating its impairment charge. As of December 31, 2016, we did not record a goodwill impairment charge related to our annual goodwill impairment test. Furthermore, at that time the fair value of each reporting unit exceeded its respective carrying value. If the carrying value of any of these reporting units exceeds the fair value when we perform a goodwill impairment test, we would record an impairment change equal to the amount by which the carrying value exceeds its fair value. This guidance is effective January 1, 2020 with early adoption permitted for interim or annual goodwill impairment tests performed after January 1, 2017. ASU 2016-02: Leases (Topic 842) Requires that a lessee recognize at the commencement date: a lease liability, which is the obligation of the lessee to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. We are currently assessing the provisions of this guidance and evaluating the timing and impact the guidance will have on our consolidated financial statements and related disclosures. We are also in the process of aggregating operating lease documentation for review. The adoption of this ASU primarily impacts the balance sheet through the recognition of a right-of-use asset and a lease liability for all leases with terms in excess of 12 months and currently classified as operating leases. This guidance is effective January 1, 2019 using a modified retrospective transition approach with early adoption permitted. ASU 2016-01: Financial Instruments - Overall (Topic 825-10) Requires the following: (1) equity investments (except those accounted for under the equity method of accounting, or those that result in consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income; (2) entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes; (3) separate presentation of financial assets and financial liabilities by measurement category and form of financial asset; and (4) the elimination of the disclosure requirement to disclose the method(s) and significant assumptions used to estimate the fair value that is required to be disclosed for financial instruments measured at amortized cost. The adoption of this guidance results in a cumulative-effect adjustment to the balance sheet, the recognition of changes in fair value of certain equity investments in net income, and enhanced disclosure. This guidance is effective January 1, 2018 with a cumulative-effect adjustment. ASU 2014-09, ASU 2015-14, ASU 2016-06, ASU 2016-10, ASU 2016-12 and ASU 2016-20: Revenue from Contracts with Customers (Topic 606) The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. We are currently evaluating the alternative methods of adoption and the effect of this guidance on our consolidated financial statements and related disclosures. To assess the impact of this standard, our internal resources have reviewed the amended guidance and attended training to assist with interpretation of the amended guidance. We are also in the process of identifying material contracts and revenue streams that are impacted by this guidance. This guidance is effective January 1, 2018 using a full or modified retrospective approach with early adoption permitted January 1, 2017.
Accrued Final Capping, Closure and Post Closure	Accrued final capping, closure and post-closure costs include the current and non-current portion of costs associated with obligations for final capping, closure and post-closure of our landfills. We estimate our future final capping, closure and post-closure costs in order to determine the final capping, closure and post-closure expense per ton of waste placed into each landfill. The anticipated time frame for paying these costs varies based on the remaining useful life of each landfill, as well as the duration of the post-closure monitoring period.

ACCOUNTING CHANGES (Tables)

ACCOUNTING CHANGES (Tables)	3 Months Ended
	Mar. 31, 2017
Accounting Changes and Error Corrections [Abstract]
Description of Recent Accounting Standards Updates ("ASU") Not Yet Adopted	A table providing a brief description of recent Accounting Standards Updates (“ASU”) to the Accounting Standards Codification (“ASC”) issued by the Financial Accounting Standards Board (“FASB”) that may have a material effect on our consolidated financial statements upon adoption follows: Standard Description Effect on the Financial Statements or Other Significant Matters Accounting standards that are pending adoption ASU 2017-04: Intangibles - Goodwill and Other (Topic 350) Requires that when an entity is performing its annual, or interim, goodwill impairment test, it should compare the fair value of the reporting unit with its carrying amount when calculating its impairment charge, noting that the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. Additionally, if applicable, an entity should consider income tax effects from any tax deductible goodwill on the carrying amount of the reporting unit when calculating its impairment charge. As of December 31, 2016, we did not record a goodwill impairment charge related to our annual goodwill impairment test. Furthermore, at that time the fair value of each reporting unit exceeded its respective carrying value. If the carrying value of any of these reporting units exceeds the fair value when we perform a goodwill impairment test, we would record an impairment change equal to the amount by which the carrying value exceeds its fair value. This guidance is effective January 1, 2020 with early adoption permitted for interim or annual goodwill impairment tests performed after January 1, 2017. ASU 2016-02: Leases (Topic 842) Requires that a lessee recognize at the commencement date: a lease liability, which is the obligation of the lessee to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. We are currently assessing the provisions of this guidance and evaluating the timing and impact the guidance will have on our consolidated financial statements and related disclosures. We are also in the process of aggregating operating lease documentation for review. The adoption of this ASU primarily impacts the balance sheet through the recognition of a right-of-use asset and a lease liability for all leases with terms in excess of 12 months and currently classified as operating leases. This guidance is effective January 1, 2019 using a modified retrospective transition approach with early adoption permitted. ASU 2016-01: Financial Instruments - Overall (Topic 825-10) Requires the following: (1) equity investments (except those accounted for under the equity method of accounting, or those that result in consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income; (2) entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes; (3) separate presentation of financial assets and financial liabilities by measurement category and form of financial asset; and (4) the elimination of the disclosure requirement to disclose the method(s) and significant assumptions used to estimate the fair value that is required to be disclosed for financial instruments measured at amortized cost. The adoption of this guidance results in a cumulative-effect adjustment to the balance sheet, the recognition of changes in fair value of certain equity investments in net income, and enhanced disclosure. This guidance is effective January 1, 2018 with a cumulative-effect adjustment. ASU 2014-09, ASU 2015-14, ASU 2016-06, ASU 2016-10, ASU 2016-12 and ASU 2016-20: Revenue from Contracts with Customers (Topic 606) The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. We are currently evaluating the alternative methods of adoption and the effect of this guidance on our consolidated financial statements and related disclosures. To assess the impact of this standard, our internal resources have reviewed the amended guidance and attended training to assist with interpretation of the amended guidance. We are also in the process of identifying material contracts and revenue streams that are impacted by this guidance. This guidance is effective January 1, 2018 using a full or modified retrospective approach with early adoption permitted January 1, 2017.

BUSINESS COMBINATIONS (Tables)

BUSINESS COMBINATIONS (Tables)	3 Months Ended
	Mar. 31, 2017
Business Combinations [Abstract]
Summary of Purchase Price Paid for Acquisitions	A summary of the purchase price for this acquisition and the allocation of the purchase price for this acquisition follows: Three Months Ended 2017 2016 Purchase Price: Cash paid for acquisitions $ 414 $ — Holdback 46 — Total 460 — Allocated as follows: Equipment 170 — Intangible assets 262 — Other liabilities, net (9 ) — Fair value of assets acquired and liabilities assumed 423 — Excess purchase price allocated to goodwill $ 37 $ —
Schedule of Unaudited Pro forma Combined Information	Unaudited pro forma combined information that shows our operational results as though each acquisition completed since the beginning of the prior fiscal year had occurred as of January 1, 2016 follows: Three Months Ended 2017 2016 Revenue $ 133,916 $ 126,426 Operating income $ 6,577 $ 1,914 Net loss attributable to common stockholders $ (217 ) $ (7,645 ) Basic earnings per share attributable to common stockholders $ (0.01 ) $ (0.19 ) Basic weighted average common shares outstanding 41,584 40,996

GOODWILL AND INTANGIBLE ASSETS

GOODWILL AND INTANGIBLE ASSETS (Tables)	3 Months Ended
	Mar. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Activity and Balances Related to Goodwill by Operating Segment	A summary of the activity and balances related to goodwill by operating segment follows: December 31, 2016 Acquisitions March 31, 2017 Eastern region $ 17,429 $ — $ 17,429 Western region 88,426 37 88,463 Recycling 12,315 — 12,315 Other 1,729 — 1,729 Total $ 119,899 $ 37 $ 119,936
Summary of Intangible Assets by Intangible Asset Type	A summary of intangible assets by intangible asset type follows: Covenants Not-to-Compete Client Lists Total Balance, March 31, 2017 Intangible assets $ 17,624 $ 16,304 $ 33,928 Less accumulated amortization (16,517 ) (9,939 ) (26,456 ) $ 1,107 $ 6,365 $ 7,472 Covenants Not-to-Compete Client Lists Total Balance, December 31, 2016 Intangible assets $ 17,594 $ 16,071 $ 33,665 Less accumulated amortization (16,402 ) (9,567 ) (25,969 ) $ 1,192 $ 6,504 $ 7,696
Summary of Intangible Amortization Expense Estimated	A summary of intangible amortization expense estimated for the five fiscal years following the fiscal year ended December 31, 2016 and thereafter follows: Estimated Future Amortization Expense as of March 31, 2017 Fiscal year ending December 31, 2017 $ 1,455 Fiscal year ending December 31, 2018 $ 1,741 Fiscal year ending December 31, 2019 $ 1,366 Fiscal year ending December 31, 2020 $ 1,168 Fiscal year ending December 31, 2021 $ 910 Thereafter $ 832

ACCRUED FINAL CAPPING, CLOSUR23

ACCRUED FINAL CAPPING, CLOSURE AND POST CLOSURE (Tables)	3 Months Ended
	Mar. 31, 2017
Asset Retirement Obligation Disclosure [Abstract]
Summary of Changes to Accrued Capping, Closure and Post-Closure Liabilities	A summary of the changes to accrued final capping, closure and post-closure liabilities follows: Three Months Ended 2017 2016 Beginning balance $ 44,207 $ 41,041 Obligations incurred 556 526 Accretion expense 965 886 Obligations settled (1) (126 ) (198 ) Ending balance $ 45,602 $ 42,255 (1) Includes amounts that are being processed through accounts payable as a part of our disbursement cycle.

LONG-TERM DEBT (Tables)

LONG-TERM DEBT (Tables)	3 Months Ended
	Mar. 31, 2017
Debt Disclosure [Abstract]
Summary of Components of Long-Term Debt and Capital Leases by Debt Instrument	A summary of long-term debt and capital leases by debt instrument follows: March 31, December 31, Senior Secured Credit Facility: Revolving Credit Facility due October 2021; bearing interest at LIBOR plus 2.75% and 3.00%, respectively $ 63,000 $ 62,600 Term Loan B Facility due October 2023; bearing interest at LIBOR plus 3.00% 349,125 350,000 Tax-Exempt Bonds: New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014 due December 2044 - fixed rate interest period through 2019; bearing interest at 3.75% 25,000 25,000 New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014R-2 due December 2044 - fixed rate interest period through 2026; bearing interest at 3.125% 15,000 15,000 Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-3 due January 2025 - fixed rate interest period through 2025; bearing interest at 5.25% 25,000 — Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2015 due August 2035 - fixed rate interest period through 2025; bearing interest at 5.125% 15,000 15,000 Vermont Economic Development Authority Solid Waste Disposal Long-Term Revenue Bonds Series 2013 due April 2036 - fixed rate interest period through 2018; bearing interest at 4.75% 16,000 16,000 Business Finance Authority of the State of New Hampshire Solid Waste Disposal Revenue Bonds Series 2013 due April 2029 - fixed rate interest period through 2019; bearing interest at 4.00% 11,000 11,000 Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-2 due January 2025 - fixed rate interest period through 2017; bore interest at 6.25% — 21,400 Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-1; letter of credit backed due January 2025 - bore interest at SIFMA Index — 3,600 Other: Capital leases maturing through April 2023; bearing interest at up to 7.70% 5,318 5,534 Notes payable maturing through January 2021; bearing interest at up to 7.00% 407 449 Principal amount of long-term debt and capital leases 524,850 525,583 Less—unamortized discount and debt issuance costs (1) 16,438 16,936 Long-term debt and capital leases less unamortized discount and debt issuance costs 508,412 508,647 Less—current maturities of long-term debt 4,669 4,686 $ 503,743 $ 503,961 (1) A summary of unamortized discount and debt issuance costs by debt instrument follows: March 31, December 31, Revolving Credit Facility $ 4,709 $ 4,965 Term Loan B Facility (including unamortized discount of $1,655 and $1,712) 7,462 7,718 New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014 1,174 1,221 New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014R-2 556 571 Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-3 666 — Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2015 743 760 Vermont Economic Development Authority Solid Waste Disposal Long-Term Revenue Bonds Series 2013 597 605 Business Finance Authority of the State of New Hampshire Solid Waste Disposal Revenue Bonds Series 2013 531 563 Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-1 — 31 Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-2 — 502 $ 16,438 $ 16,936

STOCKHOLDERS' EQUITY (Tables)

STOCKHOLDERS' EQUITY (Tables)	3 Months Ended
	Mar. 31, 2017
Equity [Abstract]
Summary of Stock Option Activity	A summary of stock option activity follows: Stock Options (1) Weighted Average Exercise Price Weighted Average Remaining Contractual Term (years) Aggregate Intrinsic Value Outstanding, December 31, 2016 1,115 $ 6.13 Granted — $ — Exercised (33 ) $ 11.01 Forfeited (2 ) $ 4.06 Outstanding, March 31, 2017 1,080 $ 5.98 5.7 $ 8,787 Exercisable, March 31, 2017 747 $ 5.51 4.5 $ 6,431 Unvested, March 31, 2017 373 $ 7.62 8.4 $ 2,421 (1) Market-based performance stock options are included at the 100% attainment level. Attainment of the maximum performance targets and market achievements would result in the issuance of an additional 40 shares of Class A common stock currently included in unvested.
Summary of Restricted Stock, Restricted Stock Unit and Performance-based Stock Unit Activity	A summary of restricted stock, restricted stock unit and performance stock unit activity follows: Restricted Stock, Restricted Stock Units, and Performance Stock Units (1) Weighted Average Exercise Price Weighted Average Remaining Contractual Term (years) Aggregate Intrinsic Value Outstanding, December 31, 2016 1,099 $ 7.03 Granted 407 $ 12.13 Class A Common Stock Vested (288 ) $ 5.01 Forfeited (17 ) $ 5.94 Outstanding, March 31, 2017 1,201 $ 9.20 1.9 $ 5,936 Unvested, March 31, 2017 1,563 $ 9.97 2.0 $ 6,539 (1) Market-based performance stock unit grants are included at the 100% attainment level. Attainment of the maximum performance targets and market achievements would result in the issuance of an additional 362 shares of Class A common stock currently included in unvested.
Summary of Changes in Balances of Each Component of Accumulated Other Comprehensive Loss	A summary of the changes in the balances of each component of accumulated other comprehensive loss , net of tax follows: Marketable Securities Interest Rate Swaps Balance, December 31, 2016 $ (68 ) $ — Other comprehensive income (loss) before reclassifications 23 (110 ) Amounts reclassified from accumulated other comprehensive income (loss) — 69 Net current-period other comprehensive income (loss) 23 (41 ) Balance, March 31, 2017 $ (45 ) $ (41 )
Summary of Reclassifications Out of Accumulated Other Comprehensive Loss	A summary of reclassifications out of accumulated other comprehensive loss , net of tax follows: Three Months Ended 2017 2016 Details About Accumulated Other Comprehensive Loss Components Amounts Reclassified Out of Accumulated Other Comprehensive Loss Affected Line Item in the Consolidated Statements of Operations Interest rate swaps 69 — Interest expense 69 — Loss before income taxes — — Provision (benefit) for income taxes $ 69 $ — Net loss

EARNINGS PER SHARE (Tables)

EARNINGS PER SHARE (Tables)	3 Months Ended
	Mar. 31, 2017
Earnings Per Share [Abstract]
Summary of Numerator and Denominators Used in Computation of Earnings Per Share	A summary of the numerator and denominators used in the computation of earnings per share follows: Three Months Ended 2017 2016 Numerator: Net loss attributable to common stockholders $ (224 ) $ (7,608 ) Denominators: Number of shares outstanding, end of period: Class A common stock 40,892 40,243 Class B common stock 988 988 Unvested restricted stock (88 ) (115 ) Effect of weighted average shares outstanding (208 ) (120 ) Basic and diluted weighted average common shares outstanding 41,584 40,996 Anti-dilutive potentially issuable shares 2,683 2,445

FAIR VALUE OF FINANCIAL INSTR27

FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)	3 Months Ended
	Mar. 31, 2017
Fair Value Disclosures [Abstract]
Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis	Summaries of our financial assets and liabilities that are measured at fair value on a recurring basis follow: Fair Value Measurement at March 31, 2017 Using: Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Interest rate derivatives $ — $ 388 $ — Restricted investments - landfill closure 1,039 — — Total $ 1,039 $ 388 $ — Liabilities: Interest rate derivatives $ — $ 454 $ — Fair Value Measurement at December 31, 2016 Using: Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Assets: Restricted investments - landfill closure $ 1,002 $ — $ —

SEGMENT REPORTING (Tables)

SEGMENT REPORTING (Tables)	3 Months Ended
	Mar. 31, 2017
Segment Reporting [Abstract]
Summary of Financial Information by Reportable Segment	Three Months Ended March 31, 2017 Segment Outside revenues Inter-company revenue Depreciation and amortization Operating income Total assets Eastern $ 38,686 $ 9,522 $ 5,404 $ 21 $ 197,817 Western 54,144 15,781 6,604 4,089 324,262 Recycling 16,635 (244 ) 1,004 1,583 50,138 Other 24,337 374 837 871 49,032 Eliminations — (25,433 ) — — — Total $ 133,802 $ — $ 13,849 $ 6,564 $ 621,249 Three Months Ended March 31, 2016 Segment Outside revenues Inter-company revenue Depreciation and amortization Operating income (loss) Total assets Eastern $ 38,987 $ 9,536 $ 6,190 $ (788 ) $ 209,315 Western 52,462 14,852 6,490 2,993 312,369 Recycling 10,638 631 1,092 (1,074 ) 48,042 Other 23,345 280 681 843 50,680 Eliminations — (25,299 ) — — — Total $ 125,432 $ — $ 14,453 $ 1,974 $ 620,406
Summary of Revenues Attributable to Services Provided by Company	A summary of our revenues attributable to services provided follows: Three Months Ended 2017 2016 Collection $ 59,838 $ 57,851 Disposal 31,281 32,253 Power generation 1,352 1,707 Processing 1,660 973 Solid waste operations 94,131 92,784 Organics 9,214 8,935 Customer solutions 13,822 13,075 Recycling 16,635 10,638 Total revenues $ 133,802 $ 125,432

BASIS OF PRESENTATION (Details)

BASIS OF PRESENTATION (Details)	3 Months Ended
	Mar. 31, 2017regional_operating_segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of regional operating segments	2

BUSINESS COMBINATIONS - Additio

BUSINESS COMBINATIONS - Additional Information (Details) - Western - transfer_station	3 Months Ended
	Mar. 31, 2017	Jun. 30, 2016
Solid Waste Collection
Business Acquisition [Line Items]
Number of transfer stations acquired	1
Transfer Stations Acquisition
Business Acquisition [Line Items]
Number of transfer stations acquired		3

BUSINESS COMBINATIONS - Summary

BUSINESS COMBINATIONS - Summary of Purchase Price Paid for Acquisitions (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Allocated as follows:
Excess purchase price allocated to goodwill	$ 119,936		$ 119,899
Transfer Stations Acquisition
Purchase Price:
Cash paid for acquisitions	414	$ 0
Holdback	46	0
Total	460	0
Allocated as follows:
Equipment	170	0
Intangible assets	262	0
Other liabilities, net	(9)	0
Fair value of assets acquired and liabilities assumed	423	0
Excess purchase price allocated to goodwill	$ 37	$ 0

BUSINESS COMBINATIONS - Schedul

BUSINESS COMBINATIONS - Schedule of Unaudited Pro forma Combined Information (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Business Combinations [Abstract]
Revenue	$ 133,916	$ 126,426
Operating income	6,577	1,914
Net loss attributable to common stockholders	$ (217)	$ (7,645)
Basic earnings per share attributable to common stockholders (in USD per share)	$ (0.01)	$ (0.19)
Basic weighted average common shares outstanding (in shares)	41,584	40,996

GOODWILL AND INTANGIBLE ASSET33

GOODWILL AND INTANGIBLE ASSETS - Schedule of Activity and Balances Related to Goodwill by Operating Segment (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2017USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 119,899
Acquisitions	37
Goodwill, ending balance	119,936
Eastern
Goodwill [Roll Forward]
Goodwill, beginning balance	17,429
Acquisitions	0
Goodwill, ending balance	17,429
Western
Goodwill [Roll Forward]
Goodwill, beginning balance	88,426
Acquisitions	37
Goodwill, ending balance	88,463
Recycling
Goodwill [Roll Forward]
Goodwill, beginning balance	12,315
Acquisitions	0
Goodwill, ending balance	12,315
Other
Goodwill [Roll Forward]
Goodwill, beginning balance	1,729
Acquisitions	0
Goodwill, ending balance	$ 1,729

GOODWILL AND INTANGIBLE ASSET34

GOODWILL AND INTANGIBLE ASSETS - Summary of Intangible Assets by Intangible Asset Type (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 33,928	$ 33,665
Less accumulated amortization	(26,456)	(25,969)
Intangible assets, net	7,472	7,696
Covenants Not-to-Compete
Finite-Lived Intangible Assets [Line Items]
Intangible assets	17,624	17,594
Less accumulated amortization	(16,517)	(16,402)
Intangible assets, net	1,107	1,192
Client Lists
Finite-Lived Intangible Assets [Line Items]
Intangible assets	16,304	16,071
Less accumulated amortization	(9,939)	(9,567)
Intangible assets, net	$ 6,365	$ 6,504

GOODWILL AND INTANGIBLE ASSET35

GOODWILL AND INTANGIBLE ASSETS - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible amortization expenses	$ 487	$ 524

GOODWILL AND INTANGIBLE ASSET36

GOODWILL AND INTANGIBLE ASSETS - Summary of Intangible Amortization Expense Estimated (Detail) $ in Thousands	Mar. 31, 2017USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Estimated Future Amortization Expense, For the fiscal year ending December 31, 2017	$ 1,455
Estimated Future Amortization Expense, For the fiscal year ending December 31, 2018	1,741
Estimated Future Amortization Expense, For the fiscal year ending December 31, 2019	1,366
Estimated Future Amortization Expense, For the fiscal year ending December 31, 2020	1,168
Estimated Future Amortization Expense, For the fiscal year ending December 31, 2021	910
Estimated Future Amortization Expense, Thereafter	$ 832

ACCRUED FINAL CAPPING, CLOSUR37

ACCRUED FINAL CAPPING, CLOSURE AND POST CLOSURE - Summary of Changes to Accrued Capping, Closure and Post-Closure Liabilities (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	$ 44,207	$ 41,041
Obligations incurred	556	526
Accretion expense	965	886
Obligations settled	(126)	(198)
Ending balance	$ 45,602	$ 42,255

LONG-TERM DEBT - Summary of Com

LONG-TERM DEBT - Summary of Components of Long-Term Debt and Capital Leases by Debt Instrument (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long-term debt and capital lease	$ 524,850	$ 525,583
Less—unamortized discount and debt issuance costs	16,438	16,936
Long-term debt and capital leases less unamortized discount and debt issuance costs	508,412	508,647
Less—current maturities of long-term debt	4,669	4,686
Non current portion of long term debt and capital lease obligation	503,743	503,961
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt and capital lease	63,000	62,600
Less—unamortized discount and debt issuance costs	4,709	4,965
New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014 due December 2044 - fixed rate interest period through 2019; bearing interest at 3.75%
Debt Instrument [Line Items]
Long-term debt and capital lease	25,000	25,000
Less—unamortized discount and debt issuance costs	1,174	1,221
New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014R-2 due December 2044 - fixed rate interest period through 2026; bearing interest at 3.125%
Debt Instrument [Line Items]
Long-term debt and capital lease	15,000	15,000
Less—unamortized discount and debt issuance costs	556	571
Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-3 due January 2025 - fixed rate interest period through 2025; bearing interest at 5.25%
Debt Instrument [Line Items]
Long-term debt and capital lease	25,000	0
Less—unamortized discount and debt issuance costs	666	0
Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2015 due August 2035 - fixed rate interest period through 2025; bearing interest at 5.125%
Debt Instrument [Line Items]
Long-term debt and capital lease	15,000	15,000
Less—unamortized discount and debt issuance costs	743	760
Vermont Economic Development Authority Solid Waste Disposal Long-Term Revenue Bonds Series 2013 due April 2036 - fixed rate interest period through 2018; bearing interest at 4.75%
Debt Instrument [Line Items]
Long-term debt and capital lease	16,000	16,000
Less—unamortized discount and debt issuance costs	597	605
Business Finance Authority of the State of New Hampshire Solid Waste Disposal Revenue Bonds Series 2013 due April 2029 - fixed rate interest period through 2019; bearing interest at 4.00%
Debt Instrument [Line Items]
Long-term debt and capital lease	11,000	11,000
Less—unamortized discount and debt issuance costs	531	563
Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-2 due January 2025 - fixed rate interest period through 2017; bore interest at 6.25%
Debt Instrument [Line Items]
Long-term debt and capital lease	0	21,400
Less—unamortized discount and debt issuance costs	0	502
Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-1; letter of credit backed due January 2025 - bore interest at SIFMA Index
Debt Instrument [Line Items]
Long-term debt and capital lease	0	3,600
Less—unamortized discount and debt issuance costs	0	31
Capital Lease Obligations
Debt Instrument [Line Items]
Long-term debt and capital lease	5,318	5,534
Notes Payable
Debt Instrument [Line Items]
Long-term debt and capital lease	407	449
Term Loan B Facility due October 2023; bearing interest at LIBOR plus 3.00% | Secured Debt
Debt Instrument [Line Items]
Long-term debt and capital lease	349,125	350,000
Less—unamortized discount and debt issuance costs	7,462	7,718
Unamortized discount	$ 1,655	$ 1,712

LONG-TERM DEBT - Summary of C39

LONG-TERM DEBT - Summary of Components of Long-Term Debt and Capital Leases by Debt Instruments, Interest Rates (Detail)	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument variable rate basis	2.75%	3.00%
New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014 due December 2044 - fixed rate interest period through 2019; bearing interest at 3.75%
Debt Instrument [Line Items]
Debt instrument stated percentage	3.75%
New York State Environmental Facilities Corporation Solid Waste Disposal Revenue Bonds Series 2014R-2 due December 2044 - fixed rate interest period through 2026; bearing interest at 3.125%
Debt Instrument [Line Items]
Debt instrument stated percentage	3.125%
Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-2 due January 2025 - fixed rate interest period through 2017; bore interest at 6.25%
Debt Instrument [Line Items]
Debt instrument stated percentage		6.25%
Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-3 due January 2025 - fixed rate interest period through 2025; bearing interest at 5.25%
Debt Instrument [Line Items]
Debt instrument stated percentage	5.25%
Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2015 due August 2035 - fixed rate interest period through 2025; bearing interest at 5.125%
Debt Instrument [Line Items]
Debt instrument stated percentage	5.125%
Vermont Economic Development Authority Solid Waste Disposal Long-Term Revenue Bonds Series 2013 due April 2036 - fixed rate interest period through 2018; bearing interest at 4.75%
Debt Instrument [Line Items]
Debt instrument stated percentage	4.75%
Business Finance Authority of the State of New Hampshire Solid Waste Disposal Revenue Bonds Series 2013 due April 2029 - fixed rate interest period through 2019; bearing interest at 4.00%
Debt Instrument [Line Items]
Debt instrument stated percentage	4.00%
Capital Lease Obligations
Debt Instrument [Line Items]
Debt instrument stated percentage	7.70%
Notes Payable
Debt Instrument [Line Items]
Debt instrument stated percentage	7.00%
Senior Subordinated Notes Due 2019 Notes
Debt Instrument [Line Items]
Debt instrument stated percentage	7.75%
Term Loan B Facility due October 2023; bearing interest at LIBOR plus 3.00% | Secured Debt
Debt Instrument [Line Items]
Debt instrument variable rate basis	3.00%

LONG-TERM DEBT - Additional Inf

LONG-TERM DEBT - Additional Information (Detail)	1 Months Ended	3 Months Ended
	Apr. 30, 2017USD ($)	Mar. 31, 2017USD ($)interest_rate_derviative	Mar. 31, 2016USD ($)	Feb. 28, 2017USD ($)
Debt Instrument [Line Items]
Gain (loss) on debt extinguishment		$ (472,000)	$ 48,000
Secured Debt | Term Loan B Facility due October 2023; bearing interest at LIBOR plus 3.00%
Debt Instrument [Line Items]
Debt instrument variable rate basis		3.00%
New York Bonds 2016 | Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-2 due January 2025 - fixed rate interest period through 2017; bore interest at 6.25%
Debt Instrument [Line Items]
Aggregate principal amount		$ 21,400,000
New York Bonds 2016 | Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-3 due January 2025 - fixed rate interest period through 2025; bearing interest at 5.25%
Debt Instrument [Line Items]
Aggregate principal amount				$ 25,000,000
Debt instrument interest rate		5.25%
Senior Subordinated Notes Due 2019 Notes
Debt Instrument [Line Items]
Debt instrument interest rate		7.75%
Maine Bonds | Variable Rate Bonds
Debt Instrument [Line Items]
Carrying value of bonds		$ 3,600,000
Subsequent Event | Secured Debt | Term Loan B Facility due October 2023; bearing interest at LIBOR plus 3.00%
Debt Instrument [Line Items]
Aggregate principal amount	$ 350,000,000
Subsequent Event | Secured Debt | Term Loan B Facility due October 2023; bearing interest at LIBOR plus 3.00%
Debt Instrument [Line Items]
Net leverage ratio	3.75
Cash Flow Hedging
Debt Instrument [Line Items]
Derivative asset fair value		388,000
Derivative liability fair value		$ 454,000
Cash Flow Hedging | Interest Rate Derivative
Debt Instrument [Line Items]
Interest rate derivatives entered into | interest_rate_derviative		3
Notional amount		$ 60,000,000
Weighted average rate paid		1.95%
Cash Flow Hedging | Interest Rate Derivative - February 2021
Debt Instrument [Line Items]
Notional amount		$ 35,000,000
Cash Flow Hedging | Interest Rate Derivative - February 2022
Debt Instrument [Line Items]
Notional amount		$ 25,000
LIBOR | Subsequent Event | Secured Debt | Term Loan B Facility due October 2023; bearing interest at LIBOR plus 3.00%
Debt Instrument [Line Items]
Debt instrument variable rate basis	2.75%
LIBOR | Cash Flow Hedging | Interest Rate Derivative
Debt Instrument [Line Items]
Floor interest rate received		1.00%
LIBOR Floor | Subsequent Event | Secured Debt | Term Loan B Facility due October 2023; bearing interest at LIBOR plus 3.00%
Debt Instrument [Line Items]
Debt instrument variable rate basis	1.00%
Base Rate | Subsequent Event | Secured Debt | Term Loan B Facility due October 2023; bearing interest at LIBOR plus 3.00%
Debt Instrument [Line Items]
Debt instrument variable rate basis	1.75%
Decrease in applicable interest margin	0.25%
Revolving Credit Facility | Subsequent Event | Line of Credit | Revolving Credit Facility due October 2021
Debt Instrument [Line Items]
Revolving facility amount	$ 160,000,000
Consolidated net leverage ratio of 3.75x or less | LIBOR | Subsequent Event | Secured Debt | Term Loan B Facility due October 2023; bearing interest at LIBOR plus 3.00%
Debt Instrument [Line Items]
Debt instrument variable rate basis	2.50%
Consolidated net leverage ratio of 3.75x or less | LIBOR Floor | Subsequent Event | Secured Debt | Term Loan B Facility due October 2023; bearing interest at LIBOR plus 3.00%
Debt Instrument [Line Items]
Debt instrument variable rate basis	1.00%
Consolidated net leverage ratio of 3.75x or less | Base Rate | Subsequent Event | Secured Debt | Term Loan B Facility due October 2023; bearing interest at LIBOR plus 3.00%
Debt Instrument [Line Items]
Debt instrument variable rate basis	1.50%

COMMITMENTS AND CONTINGENCIES -

COMMITMENTS AND CONTINGENCIES - Additional Information (Detail)	Apr. 28, 2017USD ($)	Apr. 30, 2011USD ($)	May 31, 2009USD ($)	Apr. 26, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Jan. 29, 2016	Dec. 20, 2000a
Potsdam Environmental Remediation Liability
Loss Contingencies [Line Items]
Scrap yard and solid waste transfer station (in acres) | a								25
Estimate of total undiscounted costs associated with implementing the preferred remedies		$ 12,130,000	$ 10,219,000
Remediation activities, participant share percentage							15.00%
Risk free interest rate					1.50%
Accrual for Environmental Loss Contingencies					$ 5,866,000	$ 5,866,000
Subsequent Event | Notice of Intent to Sue under the Resource Conservation and Recovery Act
Loss Contingencies [Line Items]
Shared costs				$ 5,000,000
Subsequent Event | MADEP and Casella Waste System | Notice of Intent to Sue under the Resource Conservation and Recovery Act
Loss Contingencies [Line Items]
Shared costs				$ 10,000,000
Subsequent Event | 21E Settlement and Water System Construction Funding Agreement | Bonds
Loss Contingencies [Line Items]
Bond period	20 years
Aggregate principal amount	$ 5,000,000
Town of Southbridge, Massachusetts Landfill
Loss Contingencies [Line Items]
Investigative expenditure incurred, expect recovery amount					$ 2,809,000

STOCKHOLDERS' EQUITY - Addition

STOCKHOLDERS' EQUITY - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Restricted Stock, Restricted Stock Units, and Performance-Based Stock Units
Limited Partners' Capital Account [Line Items]
Stock-based compensation expense	$ 1,058	$ 550
Restricted Stock and Restricted Stock Unit
Limited Partners' Capital Account [Line Items]
Unrecognized stock-based compensation expense, weighted average period	1 year 8 months 4 days
Total fair value of other stock awards vested	$ 3,408
Unrecognized stock-based compensation expense	$ 4,704
Performance-Based Stock Units
Limited Partners' Capital Account [Line Items]
Unrecognized stock-based compensation expense, weighted average period	2 years 2 months
Stock Options
Limited Partners' Capital Account [Line Items]
Stock-based compensation expense	$ 171	146
Aggregate intrinsic value of options exercised	53
Unrecognized stock-based compensation expense	$ 947
Unrecognized stock-based compensation expense, weighted average period	1 year
Market-based Performance Stock Options
Limited Partners' Capital Account [Line Items]
Weighted average fair value (in dollars per share)	$ 12.51
Risk free interest rate	1.45%
Expected volatility	32.80%
Dividend yield	0.00%
Amended and Restated 1997 Employee Stock Purchase Plan
Limited Partners' Capital Account [Line Items]
Stock-based compensation expense	$ 28	$ 26
Non-Employee Director | Restricted Stock Awards
Limited Partners' Capital Account [Line Items]
Options vesting period	3 years
Minimum | 2016 Plan
Limited Partners' Capital Account [Line Items]
Options vesting period	1 year
Maximum | Performance-Based Stock Units
Limited Partners' Capital Account [Line Items]
Unrecognized stock-based compensation expense	$ 7,700
Maximum | 2016 Plan
Limited Partners' Capital Account [Line Items]
Options granted period	10 years
Options vesting period	4 years
Class A Common Stock | 2016 Plan
Limited Partners' Capital Account [Line Items]
Common stock, authorized shares (in shares)			2,250,000
Number of shares available for future grant (in shares)	1,927,000
Class A Common Stock | 2006 Incentive Plan
Limited Partners' Capital Account [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized			2,723,000

STOCKHOLDERS' EQUITY - Summary

STOCKHOLDERS' EQUITY - Summary of Stock Option Activity (Detail) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017USD ($)$ / sharesshares
Stock Options
Beginning balance, outstanding (in shares)	1,115
Granted (in shares)	0
Exercised (in shares)	(33)
Forfeited (in shares)	(2)
Ending balance, outstanding (in shares)	1,080
Exercisable at end of period (in shares)	747
Unvested at end of period (in shares)	373
Weighted Average Exercise Price
Beginning balance, Outstanding (in USD per share) | $ / shares	$ 6.13
Granted (in USD per share) | $ / shares	0
Exercised (in USD per share) | $ / shares	11.01
Forfeited (in USD per share) | $ / shares	4.06
Ending balance, Outstanding (in USD per share) | $ / shares	5.98
Exercisable at end of period (in USD per share) | $ / shares	5.51
Unvested at end of period (in USD per share) | $ / shares	$ 7.62
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted Average Remaining Contractual Term, Outstanding	5 years 8 months 12 days
Weighted Average Remaining Contractual Term, Exercisable	4 years 6 months
Weighted Average Remaining Contractual Term, Unvested	8 years 4 months 24 days
Aggregate Intrinsic Value, Outstanding at end of period | $	$ 8,787
Aggregate Intrinsic Value, Exercisable at end of period | $	6,431
Aggregate Intrinsic Value, Unvested at end of period | $	$ 2,421
Market-based Performance Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Percentage of vesting of share-based compensation awards	100.00%
Issuance of additional shares (in shares)	40

STOCKHOLDERS' EQUITY - Summar44

STOCKHOLDERS' EQUITY - Summary of Restricted Stock, Restricted Stock Unit and Performance-based Stock Unit Activity (Detail) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017USD ($)$ / sharesshares
Weighted Average Exercise Price
Outstanding at beginning of period (in USD per share) | $ / shares	$ 7.03
Granted (in USD per share) | $ / shares	12.13
Forfeited (in USD per share) | $ / shares	5.94
Outstanding at end of period (in USD per share) | $ / shares	9.20
Expected to vest at end of period (in USD per share) | $ / shares	$ 9.97
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Weighted Average Remaining Contractual Term, Outstanding	1 year 11 months
Weighted Average Remaining Contractual Term, Expected to vest	2 years
Aggregate Intrinsic Value, Outstanding at end of period | $	$ 5,936
Aggregate Intrinsic Value, Expected to vest at end of period | $	$ 6,539
Restricted Stock, Restricted Stock Units, and Performance-Based Stock Units
Restricted Stock, Restricted Stock Units, and Performance-Based Stock Units
Outstanding at beginning of period | shares	1,099
Granted (in shares) | shares	407
Forfeited (in shares) | shares	(17)
Outstanding at end of period | shares	1,201
Expected to vest at end of period (in shares) | shares	1,563
Class A Common Stock
Weighted Average Exercise Price
Class A Common Stock Vested (in USD per share) | $ / shares	$ 5.01
Class A Common Stock | Restricted Stock, Restricted Stock Units, and Performance-Based Stock Units
Restricted Stock, Restricted Stock Units, and Performance-Based Stock Units
Class A Common Stock Vested (in shares) | shares	(288)

STOCKHOLDERS' EQUITY - Summar45

STOCKHOLDERS' EQUITY - Summary of Restricted Stock, Restricted Stock Unit and Performance-based Stock Unit Activity Footnote (Detail) - Performance-Based Stock Units shares in Thousands	3 Months Ended
	Mar. 31, 2017shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance-based stock units, percentage of attainment level	100.00%
Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance-based stock units	362

STOCKHOLDERS' EQUITY - Summar46

STOCKHOLDERS' EQUITY - Summary of Changes in Balances of Each Component of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ (24,550)
Other comprehensive loss, net of tax	(18)	$ (83)
Ending balance	(23,177)
Marketable Securities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(68)
Other comprehensive income (loss) before reclassifications	23
Amounts reclassified from accumulated other comprehensive income (loss)	0
Other comprehensive loss, net of tax	23
Ending balance	(45)
Interest Rate Swaps
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	0
Other comprehensive income (loss) before reclassifications	(110)
Amounts reclassified from accumulated other comprehensive income (loss)	69
Other comprehensive loss, net of tax	(41)
Ending balance	$ (41)

STOCKHOLDERS' EQUITY - Summar47

STOCKHOLDERS' EQUITY - Summary of Reclassifications Out of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	$ 6,450	$ 10,030
Loss before income taxes	208	7,763
Provision (benefit) for income taxes	16	(149)
Net loss	224	7,614
Interest rate swaps | Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	69	0
Loss before income taxes	69	0
Provision (benefit) for income taxes	0	0
Net loss	$ 69	$ 0

EARNINGS PER SHARE - Summary of

EARNINGS PER SHARE - Summary of Numerator and Denominators Used in Computation of Earnings Per Share (Detail) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Numerator:
Net loss attributable to common stockholders	$ (224)	$ (7,608)
Number of shares outstanding, end of period:
Unvested restricted stock (in shares)	(88)	(115)
Effect of weighted average shares outstanding (in shares)	(208)	(120)
Basic and diluted weighted average common shares outstanding (in shares)	41,584	40,996
Antidilutive potentially issuable shares (in shares)	2,683	2,445
Class A Common Stock
Number of shares outstanding, end of period:
Common stock, outstanding shares (in shares)	40,892	40,243	40,572
Class B Common Stock
Number of shares outstanding, end of period:
Common stock, outstanding shares (in shares)	988	988	988

FAIR VALUE OF FINANCIAL INSTR49

FAIR VALUE OF FINANCIAL INSTRUMENTS - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Assets:
Restricted assets	$ 1,039	$ 1,002
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Assets:
Interest rate derivatives	0
Restricted assets	1,039
Liabilities:
Interest rate derivative	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Restricted investments - landfill closure
Assets:
Restricted assets	1,039	1,002
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Assets:
Interest rate derivatives	388
Restricted assets	388
Liabilities:
Interest rate derivative	454
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Restricted investments - landfill closure
Assets:
Restricted assets	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Assets:
Interest rate derivatives	0
Restricted assets	0
Liabilities:
Interest rate derivative	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Restricted investments - landfill closure
Assets:
Restricted assets	$ 0	$ 0

FAIR VALUE OF FINANCIAL INSTR50

FAIR VALUE OF FINANCIAL INSTRUMENTS - Additional Information (Detail) $ in Thousands	Mar. 31, 2017USD ($)
Significant Other Observable Inputs (Level 2)
Debt Instrument [Line Items]
Carrying value of revolver debt	$ 63,000
Fair Value | Fixed Rate Bonds
Debt Instrument [Line Items]
Fair value of fixed rate debt	104,308
Carrying Value | Fixed Rate Bonds
Debt Instrument [Line Items]
Fair value of fixed rate debt	107,000
Term Loan B Facility due October 2023; bearing interest at LIBOR plus 3.00% | Fair Value | Secured Debt | Significant Other Observable Inputs (Level 2)
Debt Instrument [Line Items]
Fair value of fixed rate debt	349,125
Term Loan B Facility due October 2023; bearing interest at LIBOR plus 3.00% | Carrying Value | Secured Debt
Debt Instrument [Line Items]
Fair value of fixed rate debt	$ 351,743

SEGMENT REPORTING - Summary of

SEGMENT REPORTING - Summary of Financial Information by Reportable Segment (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Segment Reporting Information [Line Items]
Revenues	$ 133,802	$ 125,432
Inter-Company Revenues	0	0
Depreciation and amortization	13,849	14,453
Operating income (loss)	6,564	1,974
Total assets	621,249	620,406	$ 631,512
Operating Segments | Eastern
Segment Reporting Information [Line Items]
Revenues	38,686	38,987
Depreciation and amortization	5,404	6,190
Operating income (loss)	21	(788)
Total assets	197,817	209,315
Operating Segments | Western
Segment Reporting Information [Line Items]
Revenues	54,144	52,462
Depreciation and amortization	6,604	6,490
Operating income (loss)	4,089	2,993
Total assets	324,262	312,369
Operating Segments | Recycling
Segment Reporting Information [Line Items]
Revenues	16,635	10,638
Depreciation and amortization	1,004	1,092
Operating income (loss)	1,583	(1,074)
Total assets	50,138	48,042
Operating Segments | Other
Segment Reporting Information [Line Items]
Revenues	24,337	23,345
Depreciation and amortization	837	681
Operating income (loss)	871	843
Total assets	49,032	50,680
Eliminations
Segment Reporting Information [Line Items]
Revenues	0	0
Inter-Company Revenues	(25,433)	(25,299)
Depreciation and amortization	0	0
Operating income (loss)	0	0
Total assets	0	0
Eliminations | Eastern
Segment Reporting Information [Line Items]
Inter-Company Revenues	9,522	9,536
Eliminations | Western
Segment Reporting Information [Line Items]
Inter-Company Revenues	15,781	14,852
Eliminations | Recycling
Segment Reporting Information [Line Items]
Inter-Company Revenues	(244)	631
Eliminations | Other
Segment Reporting Information [Line Items]
Inter-Company Revenues	$ 374	$ 280

SEGMENT REPORTING - Summary o52

SEGMENT REPORTING - Summary of Revenues Attributable to Services Provided by Company (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Revenue from External Customer [Line Items]
Revenues	$ 133,802	$ 125,432
Collection
Revenue from External Customer [Line Items]
Revenues	59,838	57,851
Disposal
Revenue from External Customer [Line Items]
Revenues	31,281	32,253
Power generation
Revenue from External Customer [Line Items]
Revenues	1,352	1,707
Processing
Revenue from External Customer [Line Items]
Revenues	1,660	973
Solid waste operations
Revenue from External Customer [Line Items]
Revenues	94,131	92,784
Organics
Revenue from External Customer [Line Items]
Revenues	9,214	8,935
Customer solutions
Revenue from External Customer [Line Items]
Revenues	13,822	13,075
Recycling
Revenue from External Customer [Line Items]
Revenues	$ 16,635	$ 10,638