Casella Waste Systems (CWST) 10-Q 28 Aug 14 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Jul. 31, 2014	Aug. 15, 2014	Aug. 15, 2014
		Class A Common Stock [Member]	Class B Common Stock [Member]
Document Information [Line Items]	'	'	'
Document Type	'10-Q	'	'
Amendment Flag	'false	'	'
Document Period End Date	31-Jul-14	'	'
Document Fiscal Year Focus	'2015	'	'
Document Fiscal Period Focus	'Q1	'	'
Entity Registrant Name	'CASELLA WASTE SYSTEMS INC	'	'
Entity Central Index Key	'0000911177	'	'
Current Fiscal Year End Date	'--04-30	'	'
Entity Filer Category	'Accelerated Filer	'	'
Entity Common Stock, Shares Outstanding	'	39,451,203	988,200

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Jul. 31, 2014	Apr. 30, 2014
In Thousands, unless otherwise specified
CURRENT ASSETS:	'	'
Cash and cash equivalents	$2,595	$2,464
Restricted cash	76	76
Accounts receivable - trade, net of allowance for doubtful accounts of $2,081 and $1,672	59,212	52,603
Refundable income taxes	462	465
Prepaid expenses	8,359	7,176
Inventory	4,191	3,905
Deferred income taxes	2,331	2,502
Other current assets	1,314	1,255
Current assets of discontinued operations	365	359
Total current assets	78,905	70,805
Property, plant and equipment, net of accumulated depreciation and amortization of $713,611 and $695,935	403,306	403,424
Goodwill	119,139	119,139
Intangible assets, net	12,733	13,420
Restricted assets	703	681
Cost method investments	16,752	16,752
Other non-current assets	23,687	24,205
Non-current assets of discontinued operations	1,377	1,471
Total assets	656,602	649,897
CURRENT LIABILITIES:	'	'
Current maturities of long-term debt and capital leases	877	885
Accounts payable	47,372	51,788
Accrued payroll and related expenses	4,602	6,062
Accrued interest	12,955	6,087
Current accrued capping, closure and post-closure costs	4,669	7,312
Other accrued liabilities	20,000	17,612
Total current liabilities	90,475	89,746
Long-term debt and capital leases, less current portion	511,192	507,134
Accrued capping, closure and post-closure costs, less current portion	38,846	37,342
Deferred income taxes	6,956	6,954
Other long-term liabilities	16,749	17,258
COMMITMENTS AND CONTINGENCIES	'	'
Casella Waste Systems, Inc. stockholders' deficit:	'	'
Additional paid-in capital	339,529	338,625
Accumulated deficit	-347,762	-347,472
Accumulated other comprehensive income	51	39
Total Casella Waste Systems, Inc. stockholders' deficit	-7,777	-8,407
Noncontrolling interests	161	-130
Total stockholders' deficit	-7,616	-8,537
Total liabilities and stockholders' deficit	656,602	649,897
Class A Common Stock [Member]	'	'
Casella Waste Systems, Inc. stockholders' deficit:	'	'
Common stock	395	391
Total stockholders' deficit	395	391
Class B Common Stock [Member]	'	'
Casella Waste Systems, Inc. stockholders' deficit:	'	'
Common stock	10	10
Total stockholders' deficit	$10	$10

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Jul. 31, 2014	Apr. 30, 2014
In Thousands, except Share data, unless otherwise specified
Accounts receivable - trade, allowance for doubtful accounts	$2,081	$1,672
Property, plant and equipment, accumulated depreciation and amortization	$713,611	$695,935
Class A Common Stock [Member]	'	'
Common stock, authorized shares	100,000,000	100,000,000
Common stock, par value	$0.01	$0.01
Common stock, issued shares	39,451,000	39,086,000
Common stock, outstanding shares	39,451,000	39,086,000
Class B Common Stock [Member]	'	'
Common stock, authorized shares	1,000,000	1,000,000
Common stock, par value	$0.01	$0.01
Common stock, votes (in votes per share)	10	10
Common stock, issued shares	988,000	988,000
Common stock, outstanding shares	988,000	988,000

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013
Income Statement [Abstract]	'	'
Revenues	$141,387	$128,558
Operating expenses:	'	'
Cost of operations	98,766	88,419
General and administration	16,840	15,078
Depreciation and amortization	16,368	15,197
Environmental remediation charge	75	'
Severance and reorganization costs	'	107
Expense from divestiture, acquisition and financing costs	'	20
Total operating expenses	132,049	118,821
Operating income	9,338	9,737
Other expense (income):	'	'
Interest income	-88	-12
Interest expense	9,551	9,359
Loss from equity method investments	'	977
Gain on derivative instruments	-69	-654
Other income	-192	-138
Other expense, net	9,202	9,532
Income from continuing operations before income taxes and discontinued operations	136	205
Provision for income taxes	290	319
Loss from continuing operations before discontinued operations	-154	-114
Discontinued operations:	'	'
Income from discontinued operations (net of income tax provision of $0 and $0)	'	329
Loss on disposal of discontinued operations (net of income tax provision of $0 and $0)	'	-378
Net loss	-154	-163
Less: Net income attributable to noncontrolling interests	136	28
Net loss attributable to common stockholders	-290	-191
Amounts attributable to common stockholders:	'	'
Loss from continuing operations before discontinued operations	-290	-142
Income from discontinued operations, net of tax	'	329
Loss on disposal of discontinued operations, net of tax	'	-378
Net loss attributable to common stockholders	($290)	($191)
Basic and diluted earnings per share:	'	'
Loss from continuing operations before discontinued operations	($0.01)	$0
Income from discontinued operations, net of tax	'	$0.01
Loss on disposal of discontinued operations, net of tax	'	($0.01)
Net loss per common share	($0.01)	$0
Basic and diluted weighted average common shares outstanding	40,123	39,662

Consolidated_Statements_of_Ope1

Consolidated Statements of Operations (Parenthetical) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013
Income Statement [Abstract]	'	'
Income from discontinued operations, income tax provision	$0	$0
Loss on disposal of discontinued operations, income tax provision	$0	$0

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Loss (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013
Statement Of Income And Comprehensive Income [Abstract]	'	'
Net loss	($154)	($163)
Other comprehensive income (loss), net of tax:	'	'
Unrealized loss resulting from changes in fair value of derivative instruments	'	-289
Realized loss on derivative instruments reclassified into earnings	'	164
Unrealized gain resulting from changes in fair value of marketable securities	12	'
Other comprehensive income (loss), net of tax	12	-125
Comprehensive loss	-142	-288
Less: Comprehensive income attributable to noncontrolling interests	136	28
Comprehensive loss attributable to common stockholders	($278)	($316)

Consolidated_Statement_of_Stoc

Consolidated Statement of Stockholders' Deficit (USD $)	Total	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income [Member]	Noncontrolling Interest [Member]	Class A Common Stock [Member]	Class B Common Stock [Member]
In Thousands, except Share data
Balance at Apr. 30, 2014	($8,537)	$338,625	($347,472)	$39	($130)	$391	$10
Balance (in shares) at Apr. 30, 2014	'	'	'	'	'	39,086,000	988,000
Net (loss) income	-154	'	-290	'	136	'	'
Other comprehensive income	12	'	'	12	'	'	'
Issuances of Class A common stock	287	283	'	'	'	4	'
Issuances of Class A common stock, shares	'	'	'	'	'	365,000	'
Stock-based compensation	562	562	'	'	'	'	'
Contributions from noncontrolling interest holders	155	'	'	'	155	'	'
Excess tax benefit on the vesting of share based awards	59	59	'	'	'	'	'
Balance at Jul. 31, 2014	($7,616)	$339,529	($347,762)	$51	$161	$395	$10
Balance (in shares) at Jul. 31, 2014	'	'	'	'	'	39,451,000	988,000

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013
Cash Flows from Operating Activities:	'	'
Net loss	($154)	($163)
Adjustments to reconcile net loss to net cash provided by operating activities:	'	'
Income from discontinued operations, net of tax	'	-329
Loss on disposal of discontinued operations, net of tax	'	378
Gain on sale of property and equipment	-25	-164
Depreciation and amortization	16,368	15,197
Depletion of landfill operating lease obligations	3,134	2,627
Interest accretion on landfill and environmental remediation liabilities	832	1,046
Amortization of discount on senior subordinated notes	64	59
Loss from equity method investments	'	977
Gain on derivative instruments	-69	-654
Stock-based compensation	562	631
Excess tax benefit on the vesting of share based awards	-59	63
Deferred income taxes	224	260
Changes in assets and liabilities, net of effects of acquisitions and divestitures:	'	'
Accounts receivable	-6,609	-5,588
Accounts payable	-4,416	278
Prepaid expenses, inventories and other assets	-913	-2,179
Accrued expenses and other liabilities	4,642	7,087
Net cash provided by operating activities	13,581	19,526
Cash Flows from Investing Activities:	'	'
Acquisitions, net of cash acquired	'	-29
Additions to property, plant and equipment	-16,881	-13,407
Payments on landfill operating lease contracts	-962	-1,982
Payments related to investments	'	-2,148
Proceeds from sale of property and equipment	163	284
Net cash used in investing activities	-17,725	-18,354
Cash Flows from Financing Activities:	'	'
Proceeds from long-term borrowings	38,300	29,890
Principal payments on long-term debt	-34,314	-29,310
Payments of financing costs	-1	-359
Proceeds from the exercise of share based awards	143	'
Excess tax benefit on the vesting of share based awards	59	-63
Net cash provided by (used in) financing activities	4,187	158
Discontinued Operations:	'	'
Net cash used in operating activities	'	-166
Net cash provided by investing activities	88	'
Net cash provided by (used in) discontinued operations	88	-166
Net increase in cash and cash equivalents	131	1,164
Cash and cash equivalents, beginning of period	2,464	1,755
Cash and cash equivalents, end of period	2,595	2,919
Cash paid during the period for:	'	'
Interest	1,868	1,902
Income taxes, net of refunds	61	720
Supplemental Disclosures of Non-Cash Investing and Financing Activities:	'	'
Receivable due from noncontrolling interest holder	155	'
Property, plant and equipment acquired through lease obligations	'	2,301
Acquisition [Member]	'	'
Cash Flows from Investing Activities:	'	'
Additions to property, plant and equipment	($45)	($1,072)

Basis_of_Presentation

Basis of Presentation	3 Months Ended
	Jul. 31, 2014
Accounting Policies [Abstract]	'
Basis of Presentation	'
	1. BASIS OF PRESENTATION
	Casella Waste Systems, Inc. (“Parent”), its wholly-owned subsidiaries and certain partially owned entities over which it has a controlling financial interest (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 our 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 customer accounts, discontinued operations and earnings from equity method investees are included in our Other segment.
	The consolidated financial statements as of July 31, 2014 and for the three months ended July 31, 2014 and 2013 are unaudited. The accompanying consolidated financial statements, which include the accounts of the Parent, our wholly-owned subsidiaries and certain 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 the cost method of accounting. Assets and liabilities of discontinued operations and assets held-for-sale are segregated from those of continuing operations and reported in separate captions in the balance sheet, as applicable. The results of operations that have been disposed of or classified as held-for-sale and qualify for discontinued operations accounting are reported in discontinued operations, as applicable. Our significant accounting policies are more fully discussed in Item 8 of our Annual Report on Form 10-K for the year ended April 30, 2014, which was filed with the SEC on June 26, 2014.
	Preparation of our unaudited 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 unaudited 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 July 31, 2014 may not be indicative of the results for any other interim period or the eight-month transition period described below. The unaudited 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 year ended April 30, 2014.
	We consider events or transactions that have occurred after the unaudited consolidated balance sheet date of July 31, 2014, but prior to the filing of the unaudited consolidated financial statements with the SEC on this Quarterly Report on Form 10-Q. We have evaluated subsequent events through the filing date of this Quarterly Report on Form 10-Q with the SEC.
	Change in Fiscal Year
	In June 2014, we elected to change our fiscal year-end from April 30th to December 31st. The change in fiscal year will become effective for our fiscal year beginning January 1, 2015 and ending December 31, 2015. We intend to file a Transition Report on Form 10-KT for the eight-month transition period ending December 31, 2014 (“Transition Period”). This Quarterly Report on Form 10-Q for the three months ended July 31, 2014 is for the first quarter of the Transition Period.
	New Accounting Pronouncements Pending Adoption
	Revenue Recognition
	In May 2014, the Financial Accounting Standards Board (“FASB”) issued an accounting standards update for the recognition of revenue, which supersedes existing revenue recognition requirements and most industry-specific guidance. The update provides 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. This guidance is effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period, under either full or modified retrospective adoption. Early application is not permitted. We are currently assessing the potential impact of these changes to our consolidated financial statements as a result of adopting this standard.
	Discontinued Operations
	In April 2014, the FASB issued an accounting standards update for the requirements of reporting discontinued operations. The update provides that an entity or a group of components of an entity is required to be reported in discontinued operations once the component of an entity meets the held for sale criteria, is disposed of by sale, or is disposed of other than by sale only if the disposal represents a strategic shift that has, or will have, a major effect on an entity’s operations and financial results. The update also requires that additional disclosures about discontinued operations be made. This guidance is effective prospectively for annual periods, and interim reporting periods within those years, beginning after December 15, 2014, with early adoption permitted, but only for disposals, or classifications as held for sale, that have not been reported in financial statements previously issued or available for issuance. Adoption of this standard may impact the presentation of, and disclosures in, our consolidated financial statements and notes thereto.
	Adoption of New Accounting Pronouncements
	Income Taxes
	In July 2013, the FASB issued an accounting standards update for the reporting of an unrecognized tax benefit, or portion thereof, as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward. The update provides an exception, requiring the unrecognized tax benefit to be presented in the financial statements as a liability when the carryforward is not available at the reporting date under the tax laws to settle additional income taxes that would result in the disallowance of a tax provision or the tax laws do not require the entity to use, and the entity does not intend to use, the deferred tax asset for such purpose. This guidance is effective prospectively, with retrospective application permitted, for annual periods, and interim reporting periods within those years, beginning after December 15, 2013, with early adoption permitted. We adopted this guidance effective May 1, 2014 and it has not had, and we believe will not have, a material impact on our consolidated financial statements.

Intangible_Assets

Intangible Assets	3 Months Ended
	Jul. 31, 2014
Goodwill And Intangible Assets Disclosure [Abstract]	'
Intangible Assets	'
	2. INTANGIBLE ASSETS
	Intangible assets as of July 31, 2014 and April 30, 2014 consisted of the following:
		Covenants			Client Lists			Total
		Not-to-Compete
	Balance, July 31, 2014
	Intangible assets	$	17,248		$	15,806		$	33,054
	Less accumulated amortization		(15,500	)		(4,821	)		(20,321	)
		$	1,748		$	10,985		$	12,733
		Covenants			Client Lists			Total
		Not-to-Compete
	Balance, April 30, 2014
	Intangible assets	$	17,245		$	15,760		$	33,005
	Less accumulated amortization		(15,363	)		(4,222	)		(19,585	)
		$	1,882		$	11,538		$	13,420
	Estimated Amortization Expense as of July 31, 2014:
	For the eight-month transition period ending December 31, 2014	$	1,227
	For the fiscal year ending December 31, 2015	$	2,531
	For the fiscal year ending December 31, 2016	$	2,009
	For the fiscal year ending December 31, 2017	$	1,749
	For the fiscal year ending December 31, 2018	$	1,547
	Thereafter	$	3,670
	Intangible amortization expense for the three months ended July 31, 2014 and 2013 was $736 and $522, respectively.

Accrued_Capping_Closure_and_Po

Accrued Capping, Closure and Post Closure	3 Months Ended
	Jul. 31, 2014
Asset Retirement Obligation Disclosure [Abstract]	'
Accrued Capping, Closure and Post Closure	'
	3. ACCRUED 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 timeframe 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. The changes to accrued final capping, closure and post-closure liabilities for the three months ended July 31, 2014 and 2013 are as follows:
		Three Months Ended July 31,
		2014			2013
	Beginning balance	$	44,654		$	43,170
	Obligations incurred		884			877
	Accretion expense		798			1,011
	Payments		(2,821	)		(309	)
	Ending balance	$	43,515		$	44,749

Commitments_and_Contingencies

Commitments and Contingencies	3 Months Ended
	Jul. 31, 2014
Commitments And Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	4. 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 alleging environmental damage or violations of the permits and licenses pursuant to which we operate. In addition, we have been 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 the waste management business.
	In accordance with FASB Accounting Standards Codification (“ASC”) 450-20, we accrue for legal proceedings 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 ASC 450-20.
	New York Attorney General Matter
	In July 2014, we entered into an Assurance of Discontinuance (“AOD”) with the office of the New York Attorney General (“NYAG”) in connection with our commercial practices in certain specified counties in New York. The AOD requires, among other things, that we modify our service contracts for two (2) to ten (10) yard containers with our commercial customers in the specified counties by shortening the initial term of such contracts to two (2) years and providing for only one (1) extension term of one (1) year. We also agreed (i) to limit the liquidated damages to be paid by a customer if a customer prematurely terminates its contract with us to three (3) months in year one of the contract and one (1) month in year two or any extension year of the contract, (ii) to provide the NYAG with post-acquisition notice within thirty (30) days of an acquisition of a provider of solid waste services with a value of $350 or more, and (iii) to pay the State of New York the sum of $100. We recorded a charge of $100, included in general and administration costs, in the three months ended July 31, 2014. The counties in New York covered by the AOD are Allegany, Cattaraugus, Chautauqua, Chemung, Clinton, Franklin, Schuyler, St. Lawrence, Steuben, and Tompkins.
	Greenwood Street Landfill, Worcester, Massachusetts
	On July 2, 2014, we received a draft Administrative Consent Order with Penalty and Notice of Noncompliance (“Draft Order”) from the Massachusetts Department of Environmental Protection (“MADEP”) alleging that a subsidiary, NEWS of Worcester, LLC, had completed substantive closure of a portion of the Greenwood Street Landfill in Worcester, Massachusetts in 2010, at an elevation exceeding the applicable permit condition. The Draft Order seeks a civil administrative cash penalty of $67 and an additional administrative penalty in the form of a Supplemental Environmental Project in the amount of $201. We are working with the MADEP to address these allegations to arrive at an appropriate resolution thereof. It is probable that we will incur a loss with respect to this matter and we have recorded a charge of $200, included in general and administration costs, in the three months ended July 31, 2014.
	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 existing 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 potential or outstanding material claims.
	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, 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. It is unlikely that any significant costs relating to onsite remediation will be incurred until fiscal year 2016.
	WSI is jointly and severally liable for the total cost to remediate, and we initially expected to be responsible for approximately 30% of such costs pursuant to a cost-sharing agreement with NiMo and GM. Based on these estimates, we recorded an environmental remediation charge of $2,823 in the third quarter of fiscal year 2009. In the fourth quarter of fiscal year 2009, we recognized an additional charge of $1,532, representing an additional 15% of the estimated costs, in recognition of the deteriorating financial condition and eventual bankruptcy filing of GM. In the fourth quarter of fiscal year 2010, we recognized an additional charge of $335 based on changes in the expected timing of cash outflows. Based on the estimated costs in the ROD, and changes in the estimated timing of cash flows, we recorded an environmental remediation charge of $549 in the fourth quarter of fiscal year 2011. Such charges could be significantly higher if costs exceed estimates. We inflate these estimated costs in current dollars until the expected time of payment and discount the total cost to present value using a risk free interest rate of 2.0%. As of July 31, 2014 and April 30, 2014, we have recorded liabilities of $5,354 and $5,320, including the recognition of $34 of accretion expense in the three months ended July 31, 2014 and 2013, respectively.
	In September 2011, the DEC settled its environmental claim against the estate of the former GM (known as “Motors Liquidation Trust”) for future remediation costs relating to the WSI site for face value of $3,000. In addition, in November 2011 we settled our own claim against the Motors Liquidation Trust for face value of $100. These claims will be paid by GM in warrants to obtain stock of the reorganized GM. We began receiving the warrants in May 2013 and at this time there is no way to accurately estimate when the remainder of these claims will be paid. We have not assumed that any future proceeds from the sale of securities received in payment of these claims will reduce our exposure.
	Southbridge Landfill Environmental Remediation Liability
	On or about August 24, 2013, we experienced the movement of stockpiled earth at our Southbridge landfill in Southbridge, Massachusetts. The stockpiled materials consisted of soil removed and relocated to create space for the construction of additional landfill airspace at our Southbridge landfill. The earth had been relocated and stored during the fall, winter and spring construction season of fiscal year 2013.
	The movement caused some of the stockpiled earth to enter wetlands on property owned by us. On or about August 29, 2013 we notified the MADEP, and the Towns of Southbridge and Charlton, Massachusetts, of the occurrence of the movement. On or about September 6, 2013, MADEP issued a “Unilateral Administrative Order” (“UAO”) requiring us to provide MADEP with a plan to remove any materials deposited in the wetlands as a result of the movement (“Plan”). On or about October 3, 2013, we submitted the Plan to MADEP, and on or about October 15, 2013, MADEP approved the Plan and verbally issued permission for us implement the Plan. We have implemented the Plan under the supervision of MADEP.
	In January 2014, we received correspondence from the Massachusetts’ Office of the Attorney General (“MAAG”), advising us that the MAAG intended to schedule a meeting with us to discuss this incident, and to possibly file suit against us for violation of the Massachusetts Wetlands Protection, Clean Air and Solid Waste Acts. We met with the MAAG in March 2014 and again in July 2014 to discuss our ongoing remediation effort, and the parties are continuing to hold discussions regarding the resolution of this matter.
	On or about April 25, 2014, we notified MADEP and other interested parties that areas of sloughing had occurred in a plateau created as part of new cell construction at our Southbridge landfill. Some of the same contractors and technical advisors that were involved in the initial movement of stockpiled earth are also involved in the new cell construction that includes this area of sloughing. We repaired the areas of sloughing on April 25, 2014 and no damage occurred in the abutting wetlands. On May 9, 2014, MADEP issued a UAO directing us to ensure that the areas of sloughing at the plateau were repaired and to take steps to ensure that there would be no incursion into the wetlands, and requiring that we undertake corrective actions to ensure the stability of the plateau. Prior to MADEP’s issuance of the latest UAO, we were in the process of awarding a contract to a soil remediation company to undertake and ensure stability at the plateau. This contract has been awarded, and we and the contractor expect the work to be finished in September 2014. We filed a written notice of claim for an adjudicatory hearing with respect to the efficacy of MADEP’s issuance of the latest UAO, but the parties have agreed to a Stipulation that includes the withdrawal by us of our notice of claim for an adjudicatory hearing.
	We anticipate that the execution of the Plan and related matters will involve remediation costs of approximately $2,322 and that such costs could be higher if actual costs exceed estimates. We have provided our insurer with notice of the Plan, and the costs expended by us to date to comply with the Plan. We have also provided notice to certain of our contractors and technical advisors that the movement has occurred, that significant remediation costs will be incurred in executing the Plan and related matters, and that we expect our contractors and technical advisors to assist in the execution of the Plan and related matters, to share in the remediation costs thereof as responsible parties, and to provide notice to their own insurers. We believe that a loss in the range of $475 to $2,322, including the resolution of our discussions with the MAAG, after taking into account amounts we expect to be reimbursed by our insurer and third-parties, is probable and have therefore recorded a charge of $75 in the three months ended July 31, 2014. We had previously recorded a charge of $400 in fiscal year 2014 as an environmental remediation charge.

Stockholders_Equity

Stockholders' Equity	3 Months Ended
	Jul. 31, 2014
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Stockholders' Equity	'
	5. STOCKHOLDERS’ EQUITY
	Shares Available For Issuance
	In fiscal year 2007, we adopted the 2006 Stock Incentive Plan (“2006 Plan”). The 2006 Plan was amended in fiscal year 2010. Under the 2006 Plan, we may grant awards up to an aggregate amount of shares equal to the sum of: (i) 2,475 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 as are currently subject to options granted under our 1993 Incentive Stock Option Plan, 1994 Non-statutory Stock Option Plan, 1996 Option Plan, and 1997 Plan (“Prior Plans”), which are not actually issued under the Prior Plans because such options expire or otherwise result in shares not being issued. As of July 31, 2014, there were 1,169 Class A common stock equivalents available for future grant under the 2006 Plan, inclusive of additional Class A common stock equivalents that were previously issued under our terminated plans and have become available for grant because such awards expired or otherwise resulted in shares not being issued.
	Stock Options
	Options under the 2006 Plan are granted at a price equal to the prevailing fair market value of our Class A common stock at the date of grant. Generally, options granted have a term not to exceed ten years and vest over a one to four year period from the date of grant.
	A summary of stock option activity for the three months ended July 31, 2014 is as follows:
			Stock Options			Weighted			Weighted		Aggregate
						Average			Average		Intrinsic Value
						Exercise Price			Remaining
									Contractual
									Term (years)
	Outstanding, April 30, 2014			1,368		$	8.65
	Granted			100		$	4.86
	Exercised			(33	)	$	4.3
	Forfeited			(115	)	$	13.28
	Outstanding, July 31, 2014			1,320		$	8.07			5.2	$	343
	Exercisable, July 31, 2014			879		$	9.81			3.4	$	183
	Expected to vest, July 31, 2014			1,319		$	8.07			5.2	$	343
	During the three months ended July 31, 2014 and 2013, stock-based compensation expense for stock options was $109 and $115, respectively.
	As of July 31, 2014, total unrecognized stock-based compensation expense related to outstanding stock options was $1,003, which will be recognized over a weighted average period of 1.8 years.
	Other Stock Awards
	We grant restricted stock awards, restricted stock units and performance stock units under the 2006 Plan at a price equal to the fair market value of our Class A common stock at the date of grant. 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 vest on the third fiscal year-end following the grant date and are based on our attainment of a targeted average return on net assets as of the vesting date.
	A summary of restricted stock, restricted stock unit and performance stock unit activity for the three months ended July 31, 2014 is as follows:
			Restricted Stock,			Weighted			Weighted Average		Aggregate Intrinsic
			Restricted Stock Units,			Average			Remaining		Value
			and Performance Stock			Grant Price			Contractual Term
			Units (1)						(years)
	Outstanding, April 30, 2014			1,077		$	4.77
	Granted			277		$	5.28
	Class A Common Stock Vested			(301	)	$	4.82
	Forfeited			(17	)	$	4.12
	Outstanding, July 31, 2014			1,036		$	4.9			1.8	$	205
	Expected to vest, July 31, 2014			888		$	4.91			1.7	$	172
	-1	Performance stock units are included at the 100% attainment level. Attainment of maximum annual returns on net assets could result in the issuance of an additional 254 shares of Class A common stock.
	During the three months ended July 31, 2014, we awarded certain employees restricted stock units, which vest incrementally over a three year period beginning on the first anniversary of the date of grant and are based on continued employment.
	During the three months ended July 31, 2014 and 2013, stock-based compensation expense related to restricted stock, restricted stock units and performance stock units was $432 and $492, respectively.
	As of July 31, 2014, total unrecognized compensation expense related to outstanding restricted stock and restricted stock units was $2,714, which will be recognized over a weighted average period of 2.0 years. Maximum unrecognized stock-based compensation expense at July 31, 2014 related to outstanding performance stock units, and subject to the attainment of targeted maximum annual returns on net assets, was $2,449 to be recognized over a weighted average period of 0.8 years. We do not expect to recognize any compensation expense as of July 31, 2014 related to outstanding performance stock units based on our expected attainment levels.
	We also recorded $21 and $24 of stock-based compensation expense related to our Employee Stock Purchase Plan during the three months ended July 31, 2014 and 2013, respectively.
	Accumulated Other Comprehensive Income
	The change in the balance of accumulated other comprehensive income, which is included as a component of our stockholders’ deficit, is as follows:
			Marketable
			Securities
	Beginning balance, April 30, 2014		$	39
	Other comprehensive income, net of tax before reclassifications			12
	Amounts reclassified from accumulated other comprehensive income			—
	Net current-period other comprehensive income, net of tax			12
	Ending balance, July 31, 2014		$	51
	A summary of reclassifications out of accumulated other comprehensive income for the three months ended July 31, 2014 and 2013 is as follows:
			Three Months Ended
			July 31,
			2014			2013
	Details about Accumulated Other		Amount Reclassified Out of						Affected Line Item in the Consolidated
	Comprehensive Income Components		Accumulated Other						Statements of Operations
			Comprehensive Income
	Loss on derivative instruments:
	Commodity hedges		$	—		$	(164	)	Loss from equity method investments
				—			(164	)	Loss from continuing operations before income taxes and discontinued operations
				—			—		Provision for income taxes
			$	—		$	(164	)	Loss from continuing operations

Earnings_Per_Share

Earnings Per Share	3 Months Ended
	Jul. 31, 2014
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	6. EARNINGS PER SHARE
	The following table sets forth the numerator and denominator used in the computation of basic and diluted earnings per share (“EPS”):
			Three Months Ended
			July 31,
			2014			2013
	Numerator:
	Loss from continuing operations before discontinued operations attributable to common stockholders		$	(290	)	$	(142	)
	Denominator:
	Number of shares outstanding, end of period:
	Class A common stock			39,451			38,944
	Class B common stock			988			988
	Unvested restricted stock			(127	)		(131	)
	Effect of weighted average shares outstanding during period			(189	)		(139	)
	Weighted average number of common shares used in basic and diluted EPS			40,123			39,662
	Number of antidilutive potentially issuable shares not included in the diluted earnings per share calculations due to loss from continuing operations (1)			2,101			2,273
	-1	Performance stock units are included at the expected attainment levels.

Fair_Value_of_Financial_Instru

Fair Value of Financial Instruments	3 Months Ended
	Jul. 31, 2014
Fair Value Disclosures [Abstract]	'
Fair Value of Financial Instruments	'
	7. 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 which 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, restricted cash, accounts receivable-trade, restricted trust and escrow accounts held in trusts with various banks as collateral for our obligations relative to 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, restricted cash, trade receivables and trade payables approximate their respective fair values due to their short-term nature. The fair value of the restricted trust and escrow accounts are included as restricted assets in the Level 1 tier below. The fair values of the interest rate derivatives, included in the Level 2 tier below, are calculated based on the three month LIBOR yield curve that is observable at commonly quoted intervals for the full term of the swaps, adjusted by the credit risk of our counter-parties and us based on observable credit default swap rates. We recognize all derivatives on the balance sheet at fair value.
	As of July 31, 2014 our assets and liabilities that are measured at fair value on a recurring basis included the following:
		Fair Value Measurement at July 31, 2014 Using:
		Quoted Prices in		Significant Other		Significant
		Active Markets for		Observable Inputs		Unobservable Inputs
		Identical Assets		(Level 2)		(Level 3)
		(Level 1)
	Assets:
	Restricted assets	$	703	$	—	$	—
	Liabilities:
	Interest rate derivatives	$	—	$	2,259	$	—
	As of April 30, 2014 our assets and liabilities that are measured at fair value on a recurring basis included the following:
		Fair Value Measurement at April 30, 2014 Using:
		Quoted Prices in		Significant Other		Significant
		Active Markets for		Observable Inputs		Unobservable Inputs
		Identical Assets		(Level 2)		(Level 3)
		(Level 1)
	Assets:
	Restricted assets	$	681	$	—	$	—
	Liabilities:
	Interest rate derivatives	$	—	$	2,770	$	—
	Fair Value of Debt
	As of July 31, 2014, the fair value of our fixed rate debt, including our 7.75% senior subordinated notes due 2019 (“2019 Notes”), the Finance Authority of Maine Solid Waste Disposal Revenue Bonds Series 2005R-2 (“FAME Bonds 2005R-2”) and the Vermont Economic Development Authority Solid Waste Disposal Long Term Revenue Bonds Series 2013 (“Vermont Bonds”), was approximately $370,105 and the carrying value was $362,400. The fair value of the 2019 Notes is considered to be Level 1 within the fair value hierarchy as the fair value is based off of a quoted market price in an active market. The fair value of the FAME Bonds 2005R-2 and the Vermont Bonds are considered to be Level 2 within the fair value hierarchy as the fair values are determined using a discounted cash flow analysis based on current market rates for similar types of instruments taking into account our credit risk. Although we have determined the estimated fair value amounts of the FAME Bonds 2005R-2 and Vermont Bonds using available market information and a commonly accepted valuation methodology, considerable judgment is required in interpreting market data to develop the estimates of fair value. Accordingly, our estimates are not necessarily indicative of the amounts that we, or holders of these instruments, could realize in a current market exchange. 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.
	As of July 31, 2014, the fair value of our 2011 senior secured revolving credit facility (“2011 Revolver”) is considered to be Level 2 within the fair value hierarchy as its fair value approximated its carrying value of $138,000 based on current borrowing rates for similar types of borrowing arrangements.

Divestiture_Transactions_and_D

Divestiture Transactions and Discontinued Operations	3 Months Ended
	Jul. 31, 2014
Discontinued Operations And Disposal Groups [Abstract]	'
Divestiture Transactions and Discontinued Operations	'
	8. DIVESTITURE TRANSACTIONS AND DISCONTINUED OPERATIONS
	We review planned business dispositions based on available information and events that have occurred to determine whether or not a business or disposal group qualifies for discontinued operations treatment. The review consists of evaluating whether the business qualifies as a component of an entity for which the operations and cash flows are clearly distinguishable; whether it is anticipated that the cash flows of the component have been or will be eliminated from ongoing operations after the disposal transaction and by the end of the assessment period; and whether we will have any significant continuing involvement in the operations of the component after the disposal transaction. Planned business dispositions are presented as discontinued operations when all three criteria are met. Additionally, we evaluate whether the component has met the criteria to be classified as held-for-sale. To be classified as held-for-sale, the criteria established by FASB ASC 360-10 must be met as of the reporting date, including an active program to market the business and the disposition of the business within one year. A business that has not been disposed of may not be classified as discontinued operations until the held-for-sale criteria are met. No depreciation is recorded during the periods in which a disposal group is classified as held-for-sale.
	Businesses that qualify as held-for-sale are carried at the lower of their carrying value or fair value less costs to sell in the period the held-for-sale criteria are met. For a business that is classified as held-for-sale and meets the discontinued operations criteria, all initial or subsequent adjustments to the carrying value of the component are classified in discontinued operations.
	Discontinued Operations
	In fiscal year 2013, we initiated a plan to dispose of KTI BioFuels, Inc. (“BioFuels”), a construction and demolition material processing facility located in Lewiston, Maine, and as a result, the assets associated with BioFuels were classified as held-for-sale and the results of operations were recorded as income from discontinued operations. Assets of the disposal group included certain inventory along with plant and equipment. In the three months ended July 31, 2013, we executed a purchase and sale agreement with ReEnergy Lewiston LLC (“ReEnergy”), pursuant to which we agreed to sell certain assets of BioFuels, which was located in our Eastern region, to ReEnergy. We agreed to sell the BioFuels assets for undiscounted purchase consideration of $2,000, which is being paid to us in equal quarterly installments over five years commencing November 1, 2013, subject to the terms of the purchase and sale agreement. The related note receivable is recorded in current and non-current assets of discontinued operations in the consolidated balance sheets. We recognized a $378 loss on disposal of discontinued operations in the three months ended July 31, 2013 associated with the disposition.
	The operating results of these operations, including those related to prior years, have been reclassified from continuing to discontinued operations in the accompanying consolidated financial statements. Revenues and income before income taxes attributable to discontinued operations for the three months ended July 31, 2014 and 2013, respectively, are as follows:
		Three Months Ended
		July 31,
		2014		2013
	Revenues	$	—	$	3,312
	Income before income taxes	$	—	$	329
	We allocate interest expense to discontinued operations. We have also eliminated inter-company activity associated with discontinued operations.
	Divestiture Transactions
	In the first quarter of fiscal year 2013, we executed a purchase and sale agreement with the City of Biddeford, Maine, pursuant to which we agreed to sell the real property of Maine Energy Recovery Company LP (“MaineEnergy”) to the City of Biddeford, subject to satisfaction of conditions precedent and closing. We agreed to sell Maine Energy for undiscounted purchase consideration of $6,650, which is being paid to us in equal installments over 21 years, subject to the terms of the purchase and sale agreement. The transaction closed in November 2012, and we waived certain conditions precedent not satisfied at that time. In December 2012, we closed the Maine Energy facility and initiated the decommissioning process in accordance with the provisions of the agreement. Following the decommissioning of the Maine Energy facility, it is our responsibility to demolish the facility, at our cost, within twelve months of the closing date and in accordance with the terms of the purchase and sale agreement. On June 2, 2014, the United States Environmental Protection Agency provided final approval of the work plans to complete the last phase of the decommissioning process. The time for completion has been consensually extended by Maine Energy and the City of Biddeford and we expect to complete the decommissioning process by the end of October 2014, which is within the current agreed upon timeframe. Based on incurred costs to date and estimates regarding the remaining costs to fulfill our obligation under the purchase and sale agreement to demolish the facility and remediate the site, recognition of a loss on divestiture, which we do not expect, or a potential gain on divestiture of up to $1,600 is possible.

Segment_Reporting

Segment Reporting	3 Months Ended
	Jul. 31, 2014
Segment Reporting [Abstract]	'
Segment Reporting	'
	9. 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. Revenues associated with our solid waste operations are derived mainly from collection, transfer, disposal, landfill, landfill-gas-to-energy 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 customer accounts, discontinued operations, and earnings from equity method investees are included in our Other segment.
	Three Months Ended July 31, 2014
	Segment	Outside		Inter-company			Depreciation and		Operating			Total assets
		revenues		revenue			amortization		income (loss)
	Eastern	$	41,205	$	12,236		$	6,736	$	1,303		$	204,569
	Western		61,176		19,578			7,971		7,737			331,505
	Recycling		12,472		(54	)		1,065		(111	)		49,968
	Other		26,534		637			596		409			70,560
	Eliminations		—		(32,397	)		—		—			—
	Total	$	141,387	$	—		$	16,368	$	9,338		$	656,602
	Three Months Ended July 31, 2013
	Segment	Outside		Inter-company			Depreciation and		Operating			Total assets
		revenues		revenue			amortization		income (loss)
	Eastern	$	38,621	$	10,431		$	6,381	$	1,626		$	205,410
	Western		57,347		19,261			7,233		6,896			346,986
	Recycling		11,184		(5	)		1,065		(44	)		50,857
	Other		21,406		512			518		1,259			71,491
	Eliminations		—		(30,199	)		—		—			—
	Total	$	128,558	$	—		$	15,197	$	9,737		$	674,744
	Amounts of our total revenue attributable to services provided are as follows:
		Three Months Ended
		July 31,
		2014		2013
	Collection	$	60,011	$	58,213
	Disposal		40,092		35,123
	Power generation		1,940		2,041
	Processing		2,859		2,951
	Solid waste operations		104,902		98,328
	Organics		10,662		9,877
	Customer solutions		13,351		9,169
	Recycling		12,472		11,184
	Total revenues	$	141,387	$	128,558

Subsidiary_Guarantors

Subsidiary Guarantors	3 Months Ended
	Jul. 31, 2014
Organization Consolidation And Presentation Of Financial Statements [Abstract]	'
Subsidiary Guarantors	'
	10. SUBSIDIARY GUARANTORS
	Our 2019 Notes are guaranteed jointly and severally, fully and unconditionally, by our significant wholly-owned subsidiaries. The Parent is the issuer and a non-guarantor of the 2019 Notes and the Parent has no independent assets or operations. The information which follows presents the condensed consolidating financial position as of July 31, 2014 and April 30, 2014, the consolidating results of operations and comprehensive loss for the three months ended July 31, 2014 and 2013, and the condensed consolidating statements of cash flows for the three months ended July 31, 2014 and 2013 of (a) the Parent company only, (b) the combined guarantors (“Guarantors”), each of which is 100% wholly-owned by the Parent, (c) the combined non-guarantors (“Non-Guarantors”), (d) eliminating entries and (e) the consolidated total.
	CASELLA WASTE SYSTEMS, INC. AND SUBSIDIARIES
	CONDENSED CONSOLIDATING BALANCE SHEET
	AS OF JULY 31, 2014
	(in thousands, except for share and per share data)
	ASSETS	Parent			Guarantors			Non-			Elimination			Consolidated
								Guarantors
	CURRENT ASSETS:
	Cash and cash equivalents	$	1,992		$	261		$	342		$	—		$	2,595
	Restricted cash		—			76			—			—			76
	Accounts receivable - trade, net		431			58,769			12			—			59,212
	Refundable income taxes		462			—			—			—			462
	Prepaid expenses		3,640			4,710			9			—			8,359
	Inventory		—			4,151			40			—			4,191
	Deferred income taxes		2,331			—			—			—			2,331
	Other current assets		296			1,011			7			—			1,314
	Current assets of discontinued operations		—			365			—			—			365
	Total current assets		9,152			69,343			410			—			78,905
	Property, plant and equipment, net		4,160			398,497			649			—			403,306
	Goodwill		—			119,139			—			—			119,139
	Intangible assets, net		136			12,597			—			—			12,733
	Restricted assets		—			703			—			—			703
	Cost method investments		16,752			1,932			—			(1,932	)		16,752
	Investments in subsidiaries		(25,882	)		—			—			25,882			—
	Other non-current assets		13,316			10,371			—			—			23,687
	Non-current assets of discontinued operations		—			1,377			—			—			1,377
			8,482			544,616			649			23,950			577,697
	Intercompany receivable		538,820			(501,875	)		(38,877	)		1,932			—
		$	556,454		$	112,084		$	(37,818	)	$	25,882		$	656,602
	LIABILITIES AND STOCKHOLDERS’ (DEFICIT) EQUITY	Parent			Guarantors			Non-			Elimination			Consolidated
								Guarantors
	CURRENT LIABILITIES:
	Current maturities of long-term debt and capital leases	$	86		$	791		$	—		$	—		$	877
	Accounts payable		17,345			29,562			465			—			47,372
	Accrued payroll and related expenses		701			3,900			1			—			4,602
	Accrued interest		12,950			5			—			—			12,955
	Current accrued capping, closure and post-closure costs		—			4,666			3			—			4,669
	Other accrued liabilities		7,674			12,098			228			—			20,000
	Total current liabilities		38,756			51,022			697			—			90,475
	Long-term debt and capital leases, less current maturities		509,018			2,174			—			—			511,192
	Accrued capping, closure and post-closure costs, less current portion		—			38,809			37			—			38,846
	Deferred income taxes		6,956			—			—			—			6,956
	Other long-term liabilities		9,501			7,166			82			—			16,749
	STOCKHOLDERS’ (DEFICIT) EQUITY:
	Casella Waste Systems, Inc. stockholders (deficit)’ equity		(7,777	)		12,913			(38,795	)		25,882			(7,777	)
	Noncontrolling interests		—			—			161			—			161
	Total stockholders’ (deficit) equity		(7,777	)		12,913			(38,634	)		25,882			(7,616	)
		$	556,454		$	112,084		$	(37,818	)	$	25,882		$	656,602
	CASELLA WASTE SYSTEMS, INC. AND SUBSIDIARIES
	CONDENSED CONSOLIDATING BALANCE SHEET
	AS OF APRIL 30, 2014
	(in thousands, except for share and per share data)
	ASSETS	Parent			Guarantors			Non-			Elimination			Consolidated
								Guarantors
	CURRENT ASSETS:
	Cash and cash equivalents	$	2,151		$	271		$	42		$	—		$	2,464
	Restricted cash		—			76			—			—			76
	Accounts receivable - trade, net		534			51,983			86			—			52,603
	Refundable income taxes		465			—			—			—			465
	Prepaid expenses		2,617			4,557			2			—			7,176
	Inventory		—			3,852			53			—			3,905
	Deferred income taxes		2,502			—			—			—			2,502
Other current assets		312			936			7			—			1,255
Current assets of discontinued operations		—			359			—			—			359
Total current assets		8,581			62,034			190			—			70,805
Property, plant and equipment, net		4,104			398,670			650			—			403,424
Goodwill		—			119,139			—			—			119,139
Intangible assets, net		159			13,261			—			—			13,420
Restricted assets		—			681			—			—			681
Cost method investments		16,752			1,932			—			(1,932	)		16,752
Investments in subsidiaries		(36,006	)		—			—			36,006			—
Other non-current assets		13,874			10,331			—			—			24,205
Non-current assets of discontinued operations		—			1,471			—			—			1,471
		(1,117	)		545,485			650			34,074			579,092
Intercompany receivable		543,291			(506,348	)		(38,875	)		1,932			—
	$	550,755		$	101,171		$	(38,035	)	$	36,006		$	649,897
LIABILITIES AND STOCKHOLDERS’ (DEFICIT) EQUITY	Parent			Guarantors			Non-			Elimination			Consolidated
							Guarantors
CURRENT LIABILITIES:
Current maturities of long-term debt and capital leases	$	84		$	801		$	—		$	—		$	885
Accounts payable		22,678			28,286			824			—			51,788
Accrued payroll and related expenses		1,212			4,849			1			—			6,062
Accrued interest		6,084			3			—			—			6,087
Current accrued capping, closure and post-closure costs		—			7,309			3			—			7,312
Other accrued liabilities		7,289			10,081			242			—			17,612
Total current liabilities		37,347			51,329			1,070			—			89,746
Long-term debt and capital leases, less current maturities		504,836			2,298			—			—			507,134
Accrued capping, closure and post-closure costs, less current portion		—			37,306			36			—			37,342
Deferred income taxes		6,954			—			—			—			6,954
Other long-term liabilities		10,025			7,149			84			—			17,258
STOCKHOLDERS’ (DEFICIT) EQUITY:
Casella Waste Systems, Inc. stockholders (deficit)’ equity		(8,407	)		3,089			(39,095	)		36,006			(8,407	)
Noncontrolling interests		—			—			(130	)		—			(130	)
Total stockholders’ (deficit) equity		(8,407	)		3,089			(39,225	)		36,006			(8,537	)
	$	550,755		$	101,171		$	(38,035	)	$	36,006		$	649,897
CASELLA WASTE SYSTEMS, INC. AND SUBSIDIARIES
CONSOLIDATING STATEMENT OF OPERATIONS
THREE MONTHS ENDED JULY 31, 2014
(in thousands)
	Parent			Guarantors			Non-			Elimination			Consolidated
							Guarantors
Revenues	$	—		$	141,090		$	297		$	—		$	141,387
Operating expenses:
Cost of operations		17			98,718			31			—			98,766
General and administration		380			16,470			(10	)		—			16,840
Depreciation and amortization		195			16,173			—			—			16,368
Environmental remediation charge		—			75			—			—			75
		592			131,436			21			—			132,049
Operating income (loss)		(592	)		9,654			276			—			9,338
Other expense (income), net:
Interest income		—			(88	)		—			—			(88	)
Interest expense		9,589			(38	)		—			—			9,551
(Income) loss from consolidated entities		(10,089	)		—			—			10,089			—
(Gain) loss on derivative instruments		(69	)		—			—			—			(69	)
Other income		(23	)		(169	)		—			—			(192	)
Other expense, net		(592	)		(295	)		—			10,089			9,202
Income (loss) from continuing operations before income taxes		—			9,949			276			(10,089	)		136
Provision (benefit) for income taxes		290			—			—			—			290
Net income (loss)		(290	)		9,949			276			(10,089	)		(154	)
Less: Net income (loss) attributable to noncontrolling interests		—			—			136			—			136
Net income (loss) attributable to common stockholders	$	(290	)	$	9,949		$	140		$	(10,089	)	$	(290	)
CASELLA WASTE SYSTEMS, INC. AND SUBSIDIARIES
CONSOLIDATING STATEMENT OF OPERATIONS
THREE MONTHS ENDED JULY 31, 2013
(in thousands)
	Parent			Guarantors			Non-			Elimination			Consolidated
							Guarantors
Revenues	$	—		$	127,693		$	865		$	—		$	128,558
Operating expenses:
Cost of operations		—			87,782			637			—			88,419
General and administration		157			14,927			(6	)		—			15,078
Depreciation and amortization		214			14,802			181			—			15,197
Expense from divestiture, acquisition and financing costs		—			20			—			—			20
Severance and reorganization costs		—			107			—			—			107
		371			117,638			812			—			118,821
Operating income (loss)		(371	)		10,055			53			—			9,737
Other expense (income), net:
Interest income		(1	)		(11	)		—			—			(12	)
Interest expense		9,347			12			—			—			9,359
(Income) loss from equity method investments		(9,172	)		(20	)		997			9,172			977
(Gain) loss on derivative instruments		(654	)		—			—			—			(654	)
Other income		(19	)		(118	)		(1	)		—			(138	)
Other expense, net		(499	)		(137	)		996			9,172			9,532
Income (loss) from continuing operations before income taxes		128			10,192			(943	)		(9,172	)		205
Provision (benefit) for income taxes		319			—			—			—			319
Income (loss) from continuing operations		(191	)		10,192			(943	)		(9,172	)		(114	)
Discontinued operations:
Income (loss) from discontinued operations, net		—			329			—			—			329
Gain (loss) on disposal of discontinued operations, net		—			(378	)		—			—			(378	)
Net income (loss)		(191	)		10,143			(943	)		(9,172	)		(163	)
Less: Net income (loss) attributable to noncontrolling interests		—			—			28			—			28
Net income (loss) attributable to common stockholders	$	(191	)	$	10,143		$	(971	)	$	(9,172	)	$	(191	)
CASELLA WASTE SYSTEMS, INC. AND SUBSIDIARIES
CONSOLIDATING STATEMENT OF COMPREHENSIVE INCOME (LOSS)
THREE MONTHS ENDED JULY 31, 2014
(in thousands)
	Parent			Guarantors			Non-			Elimination			Consolidated
							Guarantors
Net income (loss)	$	(290	)	$	9,949		$	276		$	(10,089	)	$	(154	)
Other comprehensive income (loss), net of tax:
Unrealized gain (loss) resulting from changes in fair value of marketable securities		—			12			—			—			12
Other comprehensive income (loss), net of tax		—			12			—			—			12
Comprehensive income (loss)		(290	)		9,961			276			(10,089	)		(142	)
Less: Comprehensive income (loss) attributable to noncontrolling interests		—			—			136			—			136
Comprehensive income (loss) attributable to common stockholders	$	(290	)	$	9,961		$	140		$	(10,089	)	$	(278	)
CASELLA WASTE SYSTEMS, INC. AND SUBSIDIARIES
CONSOLIDATING STATEMENT OF COMPREHENSIVE INCOME (LOSS)
THREE MONTHS ENDED JULY 31, 2013
(in thousands)
	Parent			Guarantors			Non-			Elimination			Consolidated
							Guarantors
Net income (loss)	$	(191	)	$	10,143		$	(943	)	$	(9,172	)	$	(163	)
Other comprehensive income (loss), net of tax:
Unrealized gain (loss) resulting from changes in fair value of derivative instruments		—			—			(289	)		—			(289	)
Realized loss (gain) on derivative instruments reclassified into earnings		—			—			164			—			164
Other comprehensive income (loss), net of tax		—			—			(125	)		—			(125	)
Comprehensive income (loss)		(191	)		10,143			(1,068	)		(9,172	)		(288	)
Less: Comprehensive income (loss) attributable to noncontrolling interests		—			—			28			—			28
Comprehensive income (loss) attributable to common stockholders	$	(191	)	$	10,143		$	(1,096	)	$	(9,172	)	$	(316	)
CASELLA WASTE SYSTEMS, INC. AND SUBSIDIARIES
CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS
THREE MONTHS ENDED JULY 31, 2014
(in thousands)
	Parent			Guarantors			Non-			Elimination			Consolidated
							Guarantors
Net cash provided by (used in) operating activities	$	(9,238	)	$	22,829		$	(10	)	$	—		$	13,581
Cash Flows from Investing Activities:
Acquisition related additions to property, plant and equipment		—			(45	)		—			—			(45	)
Additions to property, plant and equipment		(227	)		(16,654	)		—			—			(16,881	)
Payments on landfill operating lease contracts		—			(962	)		—			—			(962	)
Payments related to investments		—			(310	)		310			—			—
Proceeds from sale of property and equipment		—			163			—			—			163
Net cash provided by (used in) investing activities		(227	)		(17,808	)		310			—			(17,725	)
Cash Flows from Financing Activities:
Proceeds from long-term borrowings		—			38,300			—			—			38,300
Principal payments on long-term debt		(34,181	)		(133	)		—			—			(34,314	)
Payments of financing costs		(1	)		—			—			—			(1	)
Proceeds from the exercise of share based awards		—			143			—			—			143
Excess tax benefit on the vesting of share based awards		59			—			—			—			59
Intercompany borrowings		43,429			(43,429	)		—			—			—
Net cash provided by (used in) financing activities		9,306			(5,119	)		—			—			4,187
Net cash provided by (used in) discontinued operations		—			88			—			—			88
Net increase (decrease) in cash and cash equivalents		(159	)		(10	)		300			—			131
Cash and cash equivalents, beginning of period		2,151			271			42			—			2,464
Cash and cash equivalents, end of period	$	1,992		$	261		$	342		$	—		$	2,595
CASELLA WASTE SYSTEMS, INC. AND SUBSIDIARIES
CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS
THREE MONTHS ENDED JULY 31, 2013
(in thousands)
	Parent			Guarantors			Non-			Elimination			Consolidated
							Guarantors
Net cash provided by (used in) operating activities	$	(6,951	)	$	26,358		$	119		$	—		$	19,526
Cash Flows from Investing Activities:
Acquisitions, net of cash acquired		—			(29	)		—			—			(29	)
Acquisition related additions to property, plant and equipment		—			(1,072	)		—			—			(1,072	)
Additions to property, plant and equipment		(237	)		(13,109	)		(61	)		—			(13,407	)
Payments on landfill operating lease contracts		—			(1,982	)		—			—			(1,982	)
Payments related to investments		(2,148	)		—			—			—			(2,148	)
Proceeds from sale of property and equipment		—			284			—			—			284
Net cash provided by (used in) investing activities		(2,385	)		(15,908	)		(61	)		—			(18,354	)
Cash Flows from Financing Activities:
Proceeds from long-term borrowings		29,890			—			—			—			29,890
Principal payments on long-term debt		(28,585	)		(725	)		—			—			(29,310	)
Payments of financing costs		(359	)		—			—			—			(359	)
Excess tax benefit on the vesting of share based awards		(63	)		—			—			—			(63	)
Intercompany borrowings		9,513			(9,513	)		—			—			—
Net cash provided by (used in) financing activities		10,396			(10,238	)		—			—			158
Net cash provided by (used in) discontinued operations		—			(166	)		—			—			(166	)
Net increase (decrease) in cash and cash equivalents		1,060			46			58			—			1,164
Cash and cash equivalents, beginning of period		1,260			253			242			—			1,755
Cash and cash equivalents, end of period	$	2,320		$	299		$	300		$	—		$	2,919

Basis_of_Presentation_Policies

Basis of Presentation (Policies)	3 Months Ended
	Jul. 31, 2014
Accounting Policies [Abstract]	'
New Accounting Policies Adopted and Pending Adoption	'
	New Accounting Pronouncements Pending Adoption
	Revenue Recognition
	In May 2014, the Financial Accounting Standards Board (“FASB”) issued an accounting standards update for the recognition of revenue, which supersedes existing revenue recognition requirements and most industry-specific guidance. The update provides 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. This guidance is effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period, under either full or modified retrospective adoption. Early application is not permitted. We are currently assessing the potential impact of these changes to our consolidated financial statements as a result of adopting this standard.
	Discontinued Operations
	In April 2014, the FASB issued an accounting standards update for the requirements of reporting discontinued operations. The update provides that an entity or a group of components of an entity is required to be reported in discontinued operations once the component of an entity meets the held for sale criteria, is disposed of by sale, or is disposed of other than by sale only if the disposal represents a strategic shift that has, or will have, a major effect on an entity’s operations and financial results. The update also requires that additional disclosures about discontinued operations be made. This guidance is effective prospectively for annual periods, and interim reporting periods within those years, beginning after December 15, 2014, with early adoption permitted, but only for disposals, or classifications as held for sale, that have not been reported in financial statements previously issued or available for issuance. Adoption of this standard may impact the presentation of, and disclosures in, our consolidated financial statements and notes thereto.
	Adoption of New Accounting Pronouncements
	Income Taxes
	In July 2013, the FASB issued an accounting standards update for the reporting of an unrecognized tax benefit, or portion thereof, as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward. The update provides an exception, requiring the unrecognized tax benefit to be presented in the financial statements as a liability when the carryforward is not available at the reporting date under the tax laws to settle additional income taxes that would result in the disallowance of a tax provision or the tax laws do not require the entity to use, and the entity does not intend to use, the deferred tax asset for such purpose. This guidance is effective prospectively, with retrospective application permitted, for annual periods, and interim reporting periods within those years, beginning after December 15, 2013, with early adoption permitted. We adopted this guidance effective May 1, 2014 and it has not had, and we believe will not have, a material impact on our consolidated financial statements.

Intangible_Assets_Tables

Intangible Assets (Tables)	3 Months Ended
	Jul. 31, 2014
Goodwill And Intangible Assets Disclosure [Abstract]	'
Components of Intangible Assets	'
	Intangible assets as of July 31, 2014 and April 30, 2014 consisted of the following:
		Covenants			Client Lists			Total
		Not-to-Compete
	Balance, July 31, 2014
	Intangible assets	$	17,248		$	15,806		$	33,054
	Less accumulated amortization		(15,500	)		(4,821	)		(20,321	)
		$	1,748		$	10,985		$	12,733
		Covenants			Client Lists			Total
		Not-to-Compete
	Balance, April 30, 2014
	Intangible assets	$	17,245		$	15,760		$	33,005
	Less accumulated amortization		(15,363	)		(4,222	)		(19,585	)
		$	1,882		$	11,538		$	13,420
Estimated Amortization Expense	'
	Estimated Amortization Expense as of July 31, 2014:
	For the eight-month transition period ending December 31, 2014	$	1,227
	For the fiscal year ending December 31, 2015	$	2,531
	For the fiscal year ending December 31, 2016	$	2,009
	For the fiscal year ending December 31, 2017	$	1,749
	For the fiscal year ending December 31, 2018	$	1,547
	Thereafter	$	3,670

Accrued_Capping_Closure_and_Po1

Accrued Capping, Closure and Post Closure (Tables)	3 Months Ended
	Jul. 31, 2014
Asset Retirement Obligation Disclosure [Abstract]	'
Changes to Accrued Capping, Closure and Post-Closure Liabilities	'
	The changes to accrued final capping, closure and post-closure liabilities for the three months ended July 31, 2014 and 2013 are as follows:
		Three Months Ended July 31,
		2014			2013
	Beginning balance	$	44,654		$	43,170
	Obligations incurred		884			877
	Accretion expense		798			1,011
	Payments		(2,821	)		(309	)
	Ending balance	$	43,515		$	44,749

Stockholders_Equity_Tables

Stockholders' Equity (Tables)	3 Months Ended
	Jul. 31, 2014
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Summary of Stock Option Activity	'
	A summary of stock option activity for the three months ended July 31, 2014 is as follows:
			Stock Options			Weighted			Weighted		Aggregate
						Average			Average		Intrinsic Value
						Exercise Price			Remaining
									Contractual
									Term (years)
	Outstanding, April 30, 2014			1,368		$	8.65
	Granted			100		$	4.86
	Exercised			(33	)	$	4.3
	Forfeited			(115	)	$	13.28
	Outstanding, July 31, 2014			1,320		$	8.07			5.2	$	343
	Exercisable, July 31, 2014			879		$	9.81			3.4	$	183
	Expected to vest, July 31, 2014			1,319		$	8.07			5.2	$	343
Summary of Restricted Stock, Restricted Stock Unit and Performance Stock Unit Activity	'
	A summary of restricted stock, restricted stock unit and performance stock unit activity for the three months ended July 31, 2014 is as follows:
			Restricted Stock,			Weighted			Weighted Average		Aggregate Intrinsic
			Restricted Stock Units,			Average			Remaining		Value
			and Performance Stock			Grant Price			Contractual Term
			Units (1)						(years)
	Outstanding, April 30, 2014			1,077		$	4.77
	Granted			277		$	5.28
	Class A Common Stock Vested			(301	)	$	4.82
	Forfeited			(17	)	$	4.12
	Outstanding, July 31, 2014			1,036		$	4.9			1.8	$	205
	Expected to vest, July 31, 2014			888		$	4.91			1.7	$	172
	-1	Performance stock units are included at the 100% attainment level. Attainment of maximum annual returns on net assets could result in the issuance of an additional 254 shares of Class A common stock.
Accumulated Other Comprehensive Income	'
	The change in the balance of accumulated other comprehensive income, which is included as a component of our stockholders’ deficit, is as follows:
			Marketable
			Securities
	Beginning balance, April 30, 2014		$	39
	Other comprehensive income, net of tax before reclassifications			12
	Amounts reclassified from accumulated other comprehensive income			—
	Net current-period other comprehensive income, net of tax			12
	Ending balance, July 31, 2014		$	51
Summary of Reclassification Out of Accumulated Other Comprehensive Income	'
	A summary of reclassifications out of accumulated other comprehensive income for the three months ended July 31, 2014 and 2013 is as follows:
			Three Months Ended
			July 31,
			2014			2013
	Details about Accumulated Other		Amount Reclassified Out of						Affected Line Item in the Consolidated
	Comprehensive Income Components		Accumulated Other						Statements of Operations
			Comprehensive Income
	Loss on derivative instruments:
	Commodity hedges		$	—		$	(164	)	Loss from equity method investments
				—			(164	)	Loss from continuing operations before income taxes and discontinued operations
				—			—		Provision for income taxes
			$	—		$	(164	)	Loss from continuing operations

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	3 Months Ended
	Jul. 31, 2014
Earnings Per Share [Abstract]	'
Schedule of Numerator and Denominator Used in Computation of Earnings Per Share	'
	The following table sets forth the numerator and denominator used in the computation of basic and diluted earnings per share (“EPS”):
			Three Months Ended
			July 31,
			2014			2013
	Numerator:
	Loss from continuing operations before discontinued operations attributable to common stockholders		$	(290	)	$	(142	)
	Denominator:
	Number of shares outstanding, end of period:
	Class A common stock			39,451			38,944
	Class B common stock			988			988
	Unvested restricted stock			(127	)		(131	)
	Effect of weighted average shares outstanding during period			(189	)		(139	)
	Weighted average number of common shares used in basic and diluted EPS			40,123			39,662
	Number of antidilutive potentially issuable shares not included in the diluted earnings per share calculations due to loss from continuing operations (1)			2,101			2,273
	-1	Performance stock units are included at the expected attainment levels.

Fair_Value_of_Financial_Instru1

Fair Value of Financial Instruments (Tables)	3 Months Ended
	Jul. 31, 2014
Fair Value Disclosures [Abstract]	'
Assets and Liabilities Measured at Fair Value on Recurring Basis	'
	As of July 31, 2014 our assets and liabilities that are measured at fair value on a recurring basis included the following:
		Fair Value Measurement at July 31, 2014 Using:
		Quoted Prices in		Significant Other		Significant
		Active Markets for		Observable Inputs		Unobservable Inputs
		Identical Assets		(Level 2)		(Level 3)
		(Level 1)
	Assets:
	Restricted assets	$	703	$	—	$	—
	Liabilities:
	Interest rate derivatives	$	—	$	2,259	$	—
	As of April 30, 2014 our assets and liabilities that are measured at fair value on a recurring basis included the following:
		Fair Value Measurement at April 30, 2014 Using:
		Quoted Prices in		Significant Other		Significant
		Active Markets for		Observable Inputs		Unobservable Inputs
		Identical Assets		(Level 2)		(Level 3)
		(Level 1)
	Assets:
	Restricted assets	$	681	$	—	$	—
	Liabilities:
	Interest rate derivatives	$	—	$	2,770	$	—

Divestiture_Transactions_and_D1

Divestiture Transactions and Discontinued Operations (Tables)	3 Months Ended
	Jul. 31, 2014
Discontinued Operations And Disposal Groups [Abstract]	'
Schedule of Revenues and Income Before Income Taxes Attributable to Discontinued Operations	'
	Revenues and income before income taxes attributable to discontinued operations for the three months ended July 31, 2014 and 2013, respectively, are as follows:
		Three Months Ended
		July 31,
		2014		2013
	Revenues	$	—	$	3,312
	Income before income taxes	$	—	$	329

Segment_Reporting_Tables

Segment Reporting (Tables)	3 Months Ended
	Jul. 31, 2014
Segment Reporting [Abstract]	'
Summary of Financial Information by Reportable Segment	'
	Three Months Ended July 31, 2014
	Segment	Outside		Inter-company			Depreciation and		Operating			Total assets
		revenues		revenue			amortization		income (loss)
	Eastern	$	41,205	$	12,236		$	6,736	$	1,303		$	204,569
	Western		61,176		19,578			7,971		7,737			331,505
	Recycling		12,472		(54	)		1,065		(111	)		49,968
	Other		26,534		637			596		409			70,560
	Eliminations		—		(32,397	)		—		—			—
	Total	$	141,387	$	—		$	16,368	$	9,338		$	656,602
	Three Months Ended July 31, 2013
	Segment	Outside		Inter-company			Depreciation and		Operating			Total assets
		revenues		revenue			amortization		income (loss)
	Eastern	$	38,621	$	10,431		$	6,381	$	1,626		$	205,410
	Western		57,347		19,261			7,233		6,896			346,986
	Recycling		11,184		(5	)		1,065		(44	)		50,857
	Other		21,406		512			518		1,259			71,491
	Eliminations		—		(30,199	)		—		—			—
	Total	$	128,558	$	—		$	15,197	$	9,737		$	674,744
Summary of Revenue Attributable to Services Provided by Company	'
	Amounts of our total revenue attributable to services provided are as follows:
		Three Months Ended
		July 31,
		2014		2013
	Collection	$	60,011	$	58,213
	Disposal		40,092		35,123
	Power generation		1,940		2,041
	Processing		2,859		2,951
	Solid waste operations		104,902		98,328
	Organics		10,662		9,877
	Customer solutions		13,351		9,169
	Recycling		12,472		11,184
	Total revenues	$	141,387	$	128,558

Subsidiary_Guarantors_Tables

Subsidiary Guarantors (Tables)	3 Months Ended
	Jul. 31, 2014
Organization Consolidation And Presentation Of Financial Statements [Abstract]	'
Schedule of Condensed Consolidating Balance Sheet	'
	CASELLA WASTE SYSTEMS, INC. AND SUBSIDIARIES
	CONDENSED CONSOLIDATING BALANCE SHEET
	AS OF JULY 31, 2014
	(in thousands, except for share and per share data)
	ASSETS	Parent			Guarantors			Non-			Elimination			Consolidated
								Guarantors
	CURRENT ASSETS:
	Cash and cash equivalents	$	1,992		$	261		$	342		$	—		$	2,595
	Restricted cash		—			76			—			—			76
	Accounts receivable - trade, net		431			58,769			12			—			59,212
	Refundable income taxes		462			—			—			—			462
	Prepaid expenses		3,640			4,710			9			—			8,359
	Inventory		—			4,151			40			—			4,191
	Deferred income taxes		2,331			—			—			—			2,331
	Other current assets		296			1,011			7			—			1,314
	Current assets of discontinued operations		—			365			—			—			365
	Total current assets		9,152			69,343			410			—			78,905
	Property, plant and equipment, net		4,160			398,497			649			—			403,306
	Goodwill		—			119,139			—			—			119,139
	Intangible assets, net		136			12,597			—			—			12,733
	Restricted assets		—			703			—			—			703
	Cost method investments		16,752			1,932			—			(1,932	)		16,752
	Investments in subsidiaries		(25,882	)		—			—			25,882			—
	Other non-current assets		13,316			10,371			—			—			23,687
	Non-current assets of discontinued operations		—			1,377			—			—			1,377
			8,482			544,616			649			23,950			577,697
	Intercompany receivable		538,820			(501,875	)		(38,877	)		1,932			—
		$	556,454		$	112,084		$	(37,818	)	$	25,882		$	656,602
	LIABILITIES AND STOCKHOLDERS’ (DEFICIT) EQUITY	Parent			Guarantors			Non-			Elimination			Consolidated
								Guarantors
	CURRENT LIABILITIES:
	Current maturities of long-term debt and capital leases	$	86		$	791		$	—		$	—		$	877
	Accounts payable		17,345			29,562			465			—			47,372
	Accrued payroll and related expenses		701			3,900			1			—			4,602
	Accrued interest		12,950			5			—			—			12,955
	Current accrued capping, closure and post-closure costs		—			4,666			3			—			4,669
	Other accrued liabilities		7,674			12,098			228			—			20,000
	Total current liabilities		38,756			51,022			697			—			90,475
	Long-term debt and capital leases, less current maturities		509,018			2,174			—			—			511,192
	Accrued capping, closure and post-closure costs, less current portion		—			38,809			37			—			38,846
	Deferred income taxes		6,956			—			—			—			6,956
	Other long-term liabilities		9,501			7,166			82			—			16,749
	STOCKHOLDERS’ (DEFICIT) EQUITY:
	Casella Waste Systems, Inc. stockholders (deficit)’ equity		(7,777	)		12,913			(38,795	)		25,882			(7,777	)
	Noncontrolling interests		—			—			161			—			161
	Total stockholders’ (deficit) equity		(7,777	)		12,913			(38,634	)		25,882			(7,616	)
		$	556,454		$	112,084		$	(37,818	)	$	25,882		$	656,602
	CASELLA WASTE SYSTEMS, INC. AND SUBSIDIARIES
	CONDENSED CONSOLIDATING BALANCE SHEET
	AS OF APRIL 30, 2014
	(in thousands, except for share and per share data)
	ASSETS	Parent			Guarantors			Non-			Elimination			Consolidated
								Guarantors
	CURRENT ASSETS:
	Cash and cash equivalents	$	2,151		$	271		$	42		$	—		$	2,464
	Restricted cash		—			76			—			—			76
	Accounts receivable - trade, net		534			51,983			86			—			52,603
	Refundable income taxes		465			—			—			—			465
	Prepaid expenses		2,617			4,557			2			—			7,176
	Inventory		—			3,852			53			—			3,905
	Deferred income taxes		2,502			—			—			—			2,502
	Other current assets		312			936			7			—			1,255
	Current assets of discontinued operations		—			359			—			—			359
Total current assets		8,581			62,034			190			—			70,805
Property, plant and equipment, net		4,104			398,670			650			—			403,424
Goodwill		—			119,139			—			—			119,139
Intangible assets, net		159			13,261			—			—			13,420
Restricted assets		—			681			—			—			681
Cost method investments		16,752			1,932			—			(1,932	)		16,752
Investments in subsidiaries		(36,006	)		—			—			36,006			—
Other non-current assets		13,874			10,331			—			—			24,205
Non-current assets of discontinued operations		—			1,471			—			—			1,471
		(1,117	)		545,485			650			34,074			579,092
Intercompany receivable		543,291			(506,348	)		(38,875	)		1,932			—
	$	550,755		$	101,171		$	(38,035	)	$	36,006		$	649,897
LIABILITIES AND STOCKHOLDERS’ (DEFICIT) EQUITY	Parent			Guarantors			Non-			Elimination			Consolidated
							Guarantors
CURRENT LIABILITIES:
Current maturities of long-term debt and capital leases	$	84		$	801		$	—		$	—		$	885
Accounts payable		22,678			28,286			824			—			51,788
Accrued payroll and related expenses		1,212			4,849			1			—			6,062
Accrued interest		6,084			3			—			—			6,087
Current accrued capping, closure and post-closure costs		—			7,309			3			—			7,312
Other accrued liabilities		7,289			10,081			242			—			17,612
Total current liabilities		37,347			51,329			1,070			—			89,746
Long-term debt and capital leases, less current maturities		504,836			2,298			—			—			507,134
Accrued capping, closure and post-closure costs, less current portion		—			37,306			36			—			37,342
Deferred income taxes		6,954			—			—			—			6,954
Other long-term liabilities		10,025			7,149			84			—			17,258
STOCKHOLDERS’ (DEFICIT) EQUITY:
Casella Waste Systems, Inc. stockholders (deficit)’ equity		(8,407	)		3,089			(39,095	)		36,006			(8,407	)
Noncontrolling interests		—			—			(130	)		—			(130	)
Total stockholders’ (deficit) equity		(8,407	)		3,089			(39,225	)		36,006			(8,537	)
	$	550,755		$	101,171		$	(38,035	)	$	36,006		$	649,897
Schedule of Consolidating Statement of Operations	'
	CASELLA WASTE SYSTEMS, INC. AND SUBSIDIARIES
	CONSOLIDATING STATEMENT OF OPERATIONS
	THREE MONTHS ENDED JULY 31, 2014
	(in thousands)
		Parent			Guarantors			Non-			Elimination			Consolidated
								Guarantors
	Revenues	$	—		$	141,090		$	297		$	—		$	141,387
	Operating expenses:
	Cost of operations		17			98,718			31			—			98,766
	General and administration		380			16,470			(10	)		—			16,840
	Depreciation and amortization		195			16,173			—			—			16,368
	Environmental remediation charge		—			75			—			—			75
			592			131,436			21			—			132,049
	Operating income (loss)		(592	)		9,654			276			—			9,338
	Other expense (income), net:
	Interest income		—			(88	)		—			—			(88	)
	Interest expense		9,589			(38	)		—			—			9,551
	(Income) loss from consolidated entities		(10,089	)		—			—			10,089			—
	(Gain) loss on derivative instruments		(69	)		—			—			—			(69	)
	Other income		(23	)		(169	)		—			—			(192	)
	Other expense, net		(592	)		(295	)		—			10,089			9,202
	Income (loss) from continuing operations before income taxes		—			9,949			276			(10,089	)		136
	Provision (benefit) for income taxes		290			—			—			—			290
	Net income (loss)		(290	)		9,949			276			(10,089	)		(154	)
	Less: Net income (loss) attributable to noncontrolling interests		—			—			136			—			136
	Net income (loss) attributable to common stockholders	$	(290	)	$	9,949		$	140		$	(10,089	)	$	(290	)
	CASELLA WASTE SYSTEMS, INC. AND SUBSIDIARIES
	CONSOLIDATING STATEMENT OF OPERATIONS
	THREE MONTHS ENDED JULY 31, 2013
	(in thousands)
		Parent			Guarantors			Non-			Elimination			Consolidated
								Guarantors
	Revenues	$	—		$	127,693		$	865		$	—		$	128,558
	Operating expenses:
	Cost of operations		—			87,782			637			—			88,419
	General and administration		157			14,927			(6	)		—			15,078
	Depreciation and amortization		214			14,802			181			—			15,197
	Expense from divestiture, acquisition and financing costs		—			20			—			—			20
	Severance and reorganization costs		—			107			—			—			107
			371			117,638			812			—			118,821
	Operating income (loss)		(371	)		10,055			53			—			9,737
	Other expense (income), net:
	Interest income		(1	)		(11	)		—			—			(12	)
	Interest expense		9,347			12			—			—			9,359
	(Income) loss from equity method investments		(9,172	)		(20	)		997			9,172			977
	(Gain) loss on derivative instruments		(654	)		—			—			—			(654	)
	Other income		(19	)		(118	)		(1	)		—			(138	)
	Other expense, net		(499	)		(137	)		996			9,172			9,532
	Income (loss) from continuing operations before income taxes		128			10,192			(943	)		(9,172	)		205
	Provision (benefit) for income taxes		319			—			—			—			319
	Income (loss) from continuing operations		(191	)		10,192			(943	)		(9,172	)		(114	)
	Discontinued operations:
	Income (loss) from discontinued operations, net		—			329			—			—			329
	Gain (loss) on disposal of discontinued operations, net		—			(378	)		—			—			(378	)
	Net income (loss)		(191	)		10,143			(943	)		(9,172	)		(163	)
	Less: Net income (loss) attributable to noncontrolling interests		—			—			28			—			28
	Net income (loss) attributable to common stockholders	$	(191	)	$	10,143		$	(971	)	$	(9,172	)	$	(191	)
Schedule of Consolidating Statement of Comprehensive Income (Loss)	'
	CASELLA WASTE SYSTEMS, INC. AND SUBSIDIARIES
	CONSOLIDATING STATEMENT OF COMPREHENSIVE INCOME (LOSS)
	THREE MONTHS ENDED JULY 31, 2014
	(in thousands)
		Parent			Guarantors			Non-			Elimination			Consolidated
								Guarantors
	Net income (loss)	$	(290	)	$	9,949		$	276		$	(10,089	)	$	(154	)
	Other comprehensive income (loss), net of tax:
	Unrealized gain (loss) resulting from changes in fair value of marketable securities		—			12			—			—			12
	Other comprehensive income (loss), net of tax		—			12			—			—			12
	Comprehensive income (loss)		(290	)		9,961			276			(10,089	)		(142	)
	Less: Comprehensive income (loss) attributable to noncontrolling interests		—			—			136			—			136
	Comprehensive income (loss) attributable to common stockholders	$	(290	)	$	9,961		$	140		$	(10,089	)	$	(278	)
	CASELLA WASTE SYSTEMS, INC. AND SUBSIDIARIES
	CONSOLIDATING STATEMENT OF COMPREHENSIVE INCOME (LOSS)
	THREE MONTHS ENDED JULY 31, 2013
	(in thousands)
		Parent			Guarantors			Non-			Elimination			Consolidated
								Guarantors
	Net income (loss)	$	(191	)	$	10,143		$	(943	)	$	(9,172	)	$	(163	)
	Other comprehensive income (loss), net of tax:
	Unrealized gain (loss) resulting from changes in fair value of derivative instruments		—			—			(289	)		—			(289	)
	Realized loss (gain) on derivative instruments reclassified into earnings		—			—			164			—			164
	Other comprehensive income (loss), net of tax		—			—			(125	)		—			(125	)
	Comprehensive income (loss)		(191	)		10,143			(1,068	)		(9,172	)		(288	)
	Less: Comprehensive income (loss) attributable to noncontrolling interests		—			—			28			—			28
	Comprehensive income (loss) attributable to common stockholders	$	(191	)	$	10,143		$	(1,096	)	$	(9,172	)	$	(316	)
Schedule of Condensed Consolidating Statement of Cash Flows	'
	CASELLA WASTE SYSTEMS, INC. AND SUBSIDIARIES
	CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS
	THREE MONTHS ENDED JULY 31, 2014
	(in thousands)
		Parent			Guarantors			Non-			Elimination			Consolidated
								Guarantors
	Net cash provided by (used in) operating activities	$	(9,238	)	$	22,829		$	(10	)	$	—		$	13,581
	Cash Flows from Investing Activities:
	Acquisition related additions to property, plant and equipment		—			(45	)		—			—			(45	)
	Additions to property, plant and equipment		(227	)		(16,654	)		—			—			(16,881	)
	Payments on landfill operating lease contracts		—			(962	)		—			—			(962	)
	Payments related to investments		—			(310	)		310			—			—
	Proceeds from sale of property and equipment		—			163			—			—			163
	Net cash provided by (used in) investing activities		(227	)		(17,808	)		310			—			(17,725	)
	Cash Flows from Financing Activities:
	Proceeds from long-term borrowings		—			38,300			—			—			38,300
	Principal payments on long-term debt		(34,181	)		(133	)		—			—			(34,314	)
	Payments of financing costs		(1	)		—			—			—			(1	)
	Proceeds from the exercise of share based awards		—			143			—			—			143
	Excess tax benefit on the vesting of share based awards		59			—			—			—			59
	Intercompany borrowings		43,429			(43,429	)		—			—			—
	Net cash provided by (used in) financing activities		9,306			(5,119	)		—			—			4,187
	Net cash provided by (used in) discontinued operations		—			88			—			—			88
	Net increase (decrease) in cash and cash equivalents		(159	)		(10	)		300			—			131
	Cash and cash equivalents, beginning of period		2,151			271			42			—			2,464
	Cash and cash equivalents, end of period	$	1,992		$	261		$	342		$	—		$	2,595
	CASELLA WASTE SYSTEMS, INC. AND SUBSIDIARIES
	CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS
	THREE MONTHS ENDED JULY 31, 2013
	(in thousands)
		Parent			Guarantors			Non-			Elimination			Consolidated
								Guarantors
	Net cash provided by (used in) operating activities	$	(6,951	)	$	26,358		$	119		$	—		$	19,526
	Cash Flows from Investing Activities:
	Acquisitions, net of cash acquired		—			(29	)		—			—			(29	)
	Acquisition related additions to property, plant and equipment		—			(1,072	)		—			—			(1,072	)
	Additions to property, plant and equipment		(237	)		(13,109	)		(61	)		—			(13,407	)
	Payments on landfill operating lease contracts		—			(1,982	)		—			—			(1,982	)
	Payments related to investments		(2,148	)		—			—			—			(2,148	)
	Proceeds from sale of property and equipment		—			284			—			—			284
	Net cash provided by (used in) investing activities		(2,385	)		(15,908	)		(61	)		—			(18,354	)
	Cash Flows from Financing Activities:
	Proceeds from long-term borrowings		29,890			—			—			—			29,890
	Principal payments on long-term debt		(28,585	)		(725	)		—			—			(29,310	)
	Payments of financing costs		(359	)		—			—			—			(359	)
	Excess tax benefit on the vesting of share based awards		(63	)		—			—			—			(63	)
	Intercompany borrowings		9,513			(9,513	)		—			—			—
	Net cash provided by (used in) financing activities		10,396			(10,238	)		—			—			158
	Net cash provided by (used in) discontinued operations		—			(166	)		—			—			(166	)
	Net increase (decrease) in cash and cash equivalents		1,060			46			58			—			1,164
	Cash and cash equivalents, beginning of period		1,260			253			242			—			1,755
	Cash and cash equivalents, end of period	$	2,320		$	299		$	300		$	—		$	2,919

Intangible_Assets_Components_o

Intangible Assets - Components of Intangible Assets (Detail) (USD $)	Jul. 31, 2014	Apr. 30, 2014
In Thousands, unless otherwise specified
Finite-Lived Intangible Assets [Line Items]	'	'
Intangible assets	$33,054	$33,005
Less accumulated amortization	-20,321	-19,585
Intangible assets, net	12,733	13,420
Covenants Not-to-Compete [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Intangible assets	17,248	17,245
Less accumulated amortization	-15,500	-15,363
Intangible assets, net	1,748	1,882
Client Lists [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Intangible assets	15,806	15,760
Less accumulated amortization	-4,821	-4,222
Intangible assets, net	$10,985	$11,538

Intangible_Assets_Additional_I

Intangible Assets - Additional Information (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013
Goodwill And Intangible Assets Disclosure [Abstract]	'	'
Intangible amortization expenses	$736	$522

Intangible_Assets_Estimated_Am

Intangible Assets - Estimated Amortization Expense (Detail) (USD $)	Jul. 31, 2014
In Thousands, unless otherwise specified
Goodwill And Intangible Assets Disclosure [Abstract]	'
Estimated Amortization Expense, For the eight-month transition period ending December 31, 2014	$1,227
Estimated Amortization Expense, For the fiscal year ending December 31, 2015	2,531
Estimated Amortization Expense, For the fiscal year ending December 31, 2016	2,009
Estimated Amortization Expense, For the fiscal year ending December 31, 2017	1,749
Estimated Amortization Expense, For the fiscal year ending December 31, 2018	1,547
Estimated Amortization Expense, Thereafter	$3,670

Accrued_Capping_Closure_and_Po2

Accrued Capping, Closure and Post Closure - Changes to Accrued Capping, Closure and Post-Closure Liabilities (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013
Asset Retirement Obligation Disclosure [Abstract]	'	'
Beginning balance	$44,654	$43,170
Obligations incurred	884	877
Accretion expense	798	1,011
Payments	-2,821	-309
Ending balance	$43,515	$44,749

Commitments_and_Contingencies_

Commitments and Contingencies - Additional Information (Detail) (USD $)

3 Months Ended

3 Months Ended

3 Months Ended

12 Months Ended

In Thousands, unless otherwise specified

Jul. 31, 2014

Jul. 31, 2014

Jul. 31, 2014

Jul. 31, 2014

Jul. 31, 2014

Jul. 31, 2014

Jul. 31, 2014

Jul. 31, 2014

Jul. 31, 2013

Apr. 30, 2011

Apr. 30, 2010

Apr. 30, 2009

Jan. 31, 2009

Apr. 30, 2014

31-May-09

Sep. 30, 2011

Nov. 30, 2011

Jul. 31, 2014

Apr. 30, 2014

New York Attorney General Matter [Member]

Greenwood Street Landfill [Member]

Greenwood Street Landfill [Member]

Minimum [Member]

General and Administration Costs [Member]

General and Administration Costs [Member]

Potsdam Environmental Remediation Liability [Member]

Potsdam Environmental Remediation Liability [Member]

Potsdam Environmental Remediation Liability [Member]

Potsdam Environmental Remediation Liability [Member]

Potsdam Environmental Remediation Liability [Member]

Potsdam Environmental Remediation Liability [Member]

Potsdam Environmental Remediation Liability [Member]

Potsdam Environmental Remediation Liability [Member]

Potsdam Environmental Remediation Liability [Member]

Potsdam Environmental Remediation Liability [Member]

Southbridge Landfill [Member]

Southbridge Landfill [Member]

Administrative Penalty [Member]

New York Attorney General Matter [Member]

New York Attorney General Matter [Member]

Greenwood Street Landfill [Member]

acre

Waste-Stream Inc. [Member]

Motors Liquidation Trust [Member]

Condition One [Member]

Condition One [Member]

Contingencies And Commitments [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Minimum acquisition value for post acquisition notice

'

'

'

'

$350

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Litigation settlement

'

100

67

201

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Litigation settlement charge

'

'

'

'

'

100

200

'

'

'

'

'

'

'

'

'

'

'

'

Scrap yard and solid waste transfer station

'

'

'

'

'

'

'

25

'

'

'

'

'

'

'

'

'

'

'

Estimate of total undiscounted costs associated with implementing the preferred remedies

'

'

'

'

'

'

'

'

'

12,130

'

'

'

'

10,219

'

'

'

'

Environmental remediation charge

75

'

'

'

'

'

'

'

'

549

335

1,532

2,823

'

'

'

'

75

400

Percentage of environmental remediation cost

'

'

'

'

'

'

'

'

'

'

'

15.00%

30.00%

'

'

'

'

'

'

Environmental remediation liability

'

'

'

'

'

'

'

5,354

'

'

'

'

'

5,320

'

'

'

'

'

Accretion expense

'

'

'

'

'

'

'

34

34

'

'

'

'

'

'

'

'

'

'

Estimate of inflation rate

'

'

'

'

'

'

'

2.00%

'

'

'

'

'

'

'

'

'

'

'

Future remediation costs

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

3,000

100

'

'

Anticipated remediation costs

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2,322

'

Loss contingency range of possible loss minimum

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

475

'

Loss contingency range of possible loss maximum

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$2,322

'

Stockholders_Equity_Additional

Stockholders' Equity - Additional Information (Detail) (USD $)

3 Months Ended

In Thousands, unless otherwise specified

Jul. 31, 2014

Jul. 31, 2013

Jul. 31, 2014

Jul. 31, 2013

Jul. 31, 2014

Jul. 31, 2014

Jul. 31, 2014

Jul. 31, 2013

Jul. 31, 2014

Jul. 31, 2014

Jul. 31, 2014

Jul. 31, 2014

Jul. 31, 2014

Apr. 30, 2007

Stock Options [Member]

Stock Options [Member]

Restricted Stock, Restricted Stock Units and Performance Stock Units [Member]

Restricted Stock, Restricted Stock Units and Performance Stock Units [Member]

Restricted Stock and Restricted Stock Unit [Member]

Performance Stock Units [Member]

Employee Stock Purchase Plan [Member]

Employee Stock Purchase Plan [Member]

Non-Employee Director [Member]

Employee [Member]

2006 Stock Incentive Plan [Member]

2006 Stock Incentive Plan [Member]

Class A Common Stock [Member]

Class A Common Stock [Member]

Restricted Stock Awards [Member]

Restricted Stock Awards [Member]

Minimum [Member]

Maximum [Member]

2006 Stock Incentive Plan [Member]

2006 Stock Incentive Plan [Member]

Limited Partners' Capital Account [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Common stock, issued shares

'

'

'

'

'

'

'

'

'

'

'

'

'

2,475

Number of shares available for future grant

'

'

'

'

'

'

'

'

'

'

'

'

1,169

'

Options vesting period

'

'

'

'

'

'

'

'

'3 years

'3 years

'1 year

'4 years

'

'

Options granted period

'

'

'

'

'

'

'

'

'

'

'

'10 years

'

'

Stock-based compensation expense

$109

$115

$432

$492

'

'

$21

$24

'

'

'

'

'

'

Unrecognized stock-based compensation expense

$1,003

'

'

'

$2,714

$2,449

'

'

'

'

'

'

'

'

Unrecognized stock-based compensation expense, weighted average period

'1 year 9 months 18 days

'

'

'

'2 years

'9 months 18 days

'

'

'

'

'

'

'

'

Stockholders_Equity_Summary_of

Stockholders' Equity - Summary of Stock Option Activity (Detail) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jul. 31, 2014
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Stock Options, Outstanding, April 30, 2014	1,368
Stock Options, Granted	100
Stock Options, Exercised	-33
Stock Options, Forfeited	-115
Stock Options, Outstanding, July 31, 2014	1,320
Stock Options, Exercisable, July 31, 2014	879
Stock Options, Expected to vest, July 31, 2014	1,319
Weighted Average Exercise Price, Outstanding, April 30, 2014	$8.65
Weighted Average Exercise Price, Granted	$4.86
Weighted Average Exercise Price, Exercised	$4.30
Weighted Average Exercise Price, Forfeited	$13.28
Weighted Average Exercise Price, Outstanding, July 31, 2014	$8.07
Weighted Average Exercise Price, Exercisable, July 31,2014	$9.81
Weighted Average Exercise Price, Expected to vest, July 31, 2014	$8.07
Weighted Average Remaining Contractual Term, Outstanding	'5 years 2 months 12 days
Weighted Average Remaining Contractual Term, Exercisable	'3 years 4 months 24 days
Weighted Average Remaining Contractual Term, Expected to vest	'5 years 2 months 12 days
Aggregate Intrinsic Value, Outstanding, July 31, 2014	$343
Aggregate Intrinsic Value, Exercisable, July 31, 2014	183
Aggregate Intrinsic Value, Expected to vest, July 31, 2014	$343

Stockholders_Equity_Summary_of1

Stockholders' Equity - Summary of Restricted Stock, Restricted Stock Unit and Performance Stock Unit Activity (Detail) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jul. 31, 2014
Schedule Of Restricted Stock Restricted Stock Unit And Performance Stock Unit Activity [Line Items]	'
Weighted Average Grant Price, Outstanding, April 30, 2014	$4.77
Weighted Average Grant Price, Granted	$5.28
Weighted Average Grant Price, Forfeited	$4.12
Weighted Average Grant Price, Outstanding, July 31, 2014	$4.90
Weighted Average Grant Price, Expected to vest, July 31, 2014	$4.91
Weighted Average Remaining Contractual Term, Outstanding	'1 year 9 months 18 days
Weighted Average Remaining Contractual Term, Expected to vest	'1 year 8 months 12 days
Aggregate Intrinsic Value, Outstanding, July 31, 2014	$205
Aggregate Intrinsic Value, Expected to vest, July 31, 2014	$172
Restricted Stock, Restricted Stock Units and Performance Stock Units [Member]	'
Schedule Of Restricted Stock Restricted Stock Unit And Performance Stock Unit Activity [Line Items]	'
Restricted Stock, Restricted Stock Units, and Performance Stock Units Outstanding, April 30, 2014	1,077
Restricted Stock, Restricted Stock Units, and Performance Stock Units, Granted	277
Restricted Stock, Restricted Stock Units, and Performance Stock Units, Forfeited	-17
Restricted Stock, Restricted Stock Units, and Performance Stock Units Outstanding, July 31, 2014	1,036
Restricted Stock, Restricted Stock Units, and Performance Stock Units, Expected to vest, July 31, 2014	888
Class A Common Stock [Member]	'
Schedule Of Restricted Stock Restricted Stock Unit And Performance Stock Unit Activity [Line Items]	'
Weighted Average Grant Price Common Stock, Vested	$4.82
Class A Common Stock [Member] | Restricted Stock, Restricted Stock Units and Performance Stock Units [Member]	'
Schedule Of Restricted Stock Restricted Stock Unit And Performance Stock Unit Activity [Line Items]	'
Restricted Stock, Restricted Stock Units, and Performance Stock Units Common Stock, Vested	-301

Stockholders_Equity_Summary_of2

Stockholders' Equity - Summary of Restricted Stock, Restricted Stock Unit and Performance Stock Unit Activity (Parenthetical) (Detail) (Performance Stock Units [Member])	3 Months Ended
In Thousands, unless otherwise specified	Jul. 31, 2014
Performance Stock Units [Member]	'
Schedule Of Restricted Stock Restricted Stock Unit And Performance Stock Unit Activity [Line Items]	'
Performance stock units, percentage of attainment level	100.00%
Common stock additional issue	254

Stockholders_Equity_Accumulate

Stockholders' Equity - Accumulated Other Comprehensive Income (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Beginning balance	$39	'
Other comprehensive income (loss), net of tax	12	-125
Ending balance	51	'
Marketable Securities [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Beginning balance	39	'
Other comprehensive income, net of tax before reclassifications	12	'
Amounts reclassified from accumulated other comprehensive income	'	'
Other comprehensive income (loss), net of tax	12	'
Ending balance	$51	'

Stockholders_Equity_Reclassifi

Stockholders' Equity - Reclassification Out of Accumulated Other Comprehensive Income (Loss) (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'
Loss from equity method investments	'	($977)
Loss from continuing operations before income taxes and discontinued operations	136	205
Provision for income taxes	-290	-319
Loss from continuing operations before discontinued operations	-154	-114
Commodity Hedges [Member] | Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Member]	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'
Loss from continuing operations before income taxes and discontinued operations	'	-164
Provision for income taxes	'	'
Loss from continuing operations before discontinued operations	'	-164
Commodity Hedges [Member] | Commodity Contract [Member] | Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Member]	'	'
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]	'	'
Loss from equity method investments	'	($164)

Earnings_Per_Share_Schedule_of

Earnings Per Share - Schedule of Numerator and Denominator Used in Computation of Earnings Per Share (Detail) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2014	Apr. 30, 2014	Jul. 31, 2013	Jul. 31, 2014	Apr. 30, 2014	Jul. 31, 2013
			Class A Common Stock [Member]	Class A Common Stock [Member]	Class A Common Stock [Member]	Class B Common Stock [Member]	Class B Common Stock [Member]	Class B Common Stock [Member]
Numerator:	'	'	'	'	'	'	'	'
Loss from continuing operations before discontinued operations attributable to common stockholders	($290)	($142)	'	'	'	'	'	'
Number of shares outstanding, end of period:	'	'	'	'	'	'	'	'
Common stock shares outstanding	'	'	39,451,000	39,086,000	38,944,000	988,000	988,000	988,000
Unvested restricted stock	-127,000	-131,000	'	'	'	'	'	'
Effect of weighted average shares outstanding during period	-189,000	-139,000	'	'	'	'	'	'
Weighted average number of common shares used in basic and diluted EPS	40,123,000	39,662,000	'	'	'	'	'	'
Number of antidilutive potentially issuable shares not included in the diluted earnings per share calculations due to loss from continuing operations	2,101,000	2,273,000	'	'	'	'	'	'

Fair_Value_of_Financial_Instru2

Fair Value of Financial Instruments - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $)	Jul. 31, 2014	Apr. 30, 2014
In Thousands, unless otherwise specified
Assets:	'	'
Restricted assets	$703	$681
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Assets:	'	'
Restricted assets	703	681
Liabilities:	'	'
Interest rate derivatives	'	'
Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Assets:	'	'
Restricted assets	'	'
Liabilities:	'	'
Interest rate derivatives	2,259	2,770
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Assets:	'	'
Restricted assets	'	'
Liabilities:	'	'
Interest rate derivatives	'	'

Fair_Value_of_Financial_Instru3

Fair Value of Financial Instruments - Additional Information (Detail) (USD $)	Jul. 31, 2014
In Thousands, unless otherwise specified
Debt Instrument [Line Items]	'
Carrying value of Revolver Debt	$138,000
2019 Notes [Member]	'
Debt Instrument [Line Items]	'
Stated percentage of senior subordinate notes	7.75%
Fixed Rate Bonds [Member]	'
Debt Instrument [Line Items]	'
Fair value of fixed rate debt	370,105
Carrying value of fixed rate debt	$362,400

Divestiture_Transactions_and_D2

Divestiture Transactions and Discontinued Operations - Additional Information (Detail) (USD $)	3 Months Ended		3 Months Ended
In Thousands, unless otherwise specified	Jul. 31, 2013	Jul. 31, 2013	Jul. 31, 2012	Oct. 31, 2014
		BioFuels Assets [Member]	Maine Energy Facility [Member]	Maine Energy Facility [Member]
				Scenario, Forecast [Member]
				Maximum [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]	'	'	'	'
Undiscounted purchase consideration	'	$2,000	$6,650	'
Undiscounted purchase consideration paid in installments	'5 years	'	'21 years	'
Loss on disposal of discontinued operations, net of tax	-378	'	'	'
Potential gain on divestiture	'	'	'	$1,600

Divestiture_Transactions_and_D3

Divestiture Transactions and Discontinued Operations - Schedule of Revenues and Income Before Income Taxes Attributable to Discontinued Operations (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013
Discontinued Operations And Disposal Groups [Abstract]	'	'
Revenues	'	$3,312
Income before income taxes	'	$329

Segment_Reporting_Summary_of_F

Segment Reporting - Summary of Financial Information by Reportable Segment (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013	Apr. 30, 2014
Segment Reporting Information [Line Items]	'	'	'
Revenue	$141,387	$128,558	'
Depreciation and amortization	16,368	15,197	'
Operating income (loss)	9,338	9,737	'
Total assets	656,602	674,744	649,897
Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Revenue	141,387	128,558	'
Operating Segments [Member] | Recycling [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Revenue	12,472	11,184	'
Depreciation and amortization	1,065	1,065	'
Operating income (loss)	-111	-44	'
Total assets	49,968	50,857	'
Operating Segments [Member] | Other [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Revenue	26,534	21,406	'
Depreciation and amortization	596	518	'
Operating income (loss)	409	1,259	'
Total assets	70,560	71,491	'
Operating Segments [Member] | Eastern [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Revenue	41,205	38,621	'
Depreciation and amortization	6,736	6,381	'
Operating income (loss)	1,303	1,626	'
Total assets	204,569	205,410	'
Operating Segments [Member] | Western [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Revenue	61,176	57,347	'
Depreciation and amortization	7,971	7,233	'
Operating income (loss)	7,737	6,896	'
Total assets	331,505	346,986	'
Inter-Company Revenue [Member] | Recycling [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Revenue	-54	-5	'
Inter-Company Revenue [Member] | Other [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Revenue	637	512	'
Inter-Company Revenue [Member] | Eliminations [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Revenue	-32,397	-30,199	'
Inter-Company Revenue [Member] | Eastern [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Revenue	12,236	10,431	'
Inter-Company Revenue [Member] | Western [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Revenue	$19,578	$19,261	'

Segment_Reporting_Summary_of_R

Segment Reporting - Summary of Revenue Attributable to Services Provided by Company (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013
Segment Reporting Information [Line Items]	'	'
Revenues	$141,387	$128,558
Operating Segments [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Revenues	141,387	128,558
Operating Segments [Member] | Solid Waste Operations [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Revenues	104,902	98,328
Operating Segments [Member] | Solid Waste Operations [Member] | Reportable Subsegments [Member] | Collection [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Revenues	60,011	58,213
Operating Segments [Member] | Solid Waste Operations [Member] | Reportable Subsegments [Member] | Disposal [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Revenues	40,092	35,123
Operating Segments [Member] | Solid Waste Operations [Member] | Reportable Subsegments [Member] | Power Generation [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Revenues	1,940	2,041
Operating Segments [Member] | Solid Waste Operations [Member] | Reportable Subsegments [Member] | Processing [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Revenues	2,859	2,951
Operating Segments [Member] | Organics [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Revenues	10,662	9,877
Operating Segments [Member] | Customer Solutions [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Revenues	13,351	9,169
Operating Segments [Member] | Recycling [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Revenues	$12,472	$11,184

Subsidiary_Guarantors_Schedule

Subsidiary Guarantors - Schedule of Condensed Consolidating Balance Sheet (Detail) (USD $)	Jul. 31, 2014	Apr. 30, 2014	Jul. 31, 2013	Apr. 30, 2013
In Thousands, unless otherwise specified
CURRENT ASSETS:	'	'	'	'
Cash and cash equivalents	$2,595	$2,464	$2,919	$1,755
Restricted cash	76	76	'	'
Accounts receivable - trade, net	59,212	52,603	'	'
Refundable income taxes	462	465	'	'
Prepaid expenses	8,359	7,176	'	'
Inventory	4,191	3,905	'	'
Deferred income taxes	2,331	2,502	'	'
Other current assets	1,314	1,255	'	'
Current assets of discontinued operations	365	359	'	'
Total current assets	78,905	70,805	'	'
Property, plant and equipment, net	403,306	403,424	'	'
Goodwill	119,139	119,139	'	'
Intangible assets, net	12,733	13,420	'	'
Restricted assets	703	681	'	'
Cost method investments	16,752	16,752	'	'
Investments in subsidiaries	'	'	'	'
Other non-current assets	23,687	24,205	'	'
Non-current assets of discontinued operations	1,377	1,471	'	'
Total non-current assets	577,697	579,092	'	'
Intercompany receivable	'	'	'	'
Total assets	656,602	649,897	674,744	'
CURRENT LIABILITIES:	'	'	'	'
Current maturities of long-term debt and capital leases	877	885	'	'
Accounts payable	47,372	51,788	'	'
Accrued payroll and related expenses	4,602	6,062	'	'
Accrued interest	12,955	6,087	'	'
Current accrued capping, closure and post-closure costs	4,669	7,312	'	'
Other accrued liabilities	20,000	17,612	'	'
Total current liabilities	90,475	89,746	'	'
Long-term debt and capital leases, less current maturities	511,192	507,134	'	'
Accrued capping, closure and post-closure costs, less current portion	38,846	37,342	'	'
Deferred income taxes	6,956	6,954	'	'
Other long-term liabilities	16,749	17,258	'	'
STOCKHOLDERS' (DEFICIT) EQUITY:	'	'	'	'
Casella Waste Systems, Inc. stockholders (deficit)' equity	-7,777	-8,407	'	'
Noncontrolling interests	161	-130	'	'
Total stockholders' (deficit) equity	-7,616	-8,537	'	'
Total liabilities and stockholders' (deficit) equity	656,602	649,897	'	'
Parent [Member]	'	'	'	'
CURRENT ASSETS:	'	'	'	'
Cash and cash equivalents	1,992	2,151	2,320	1,260
Restricted cash	'	'	'	'
Accounts receivable - trade, net	431	534	'	'
Refundable income taxes	462	465	'	'
Prepaid expenses	3,640	2,617	'	'
Inventory	'	'	'	'
Deferred income taxes	2,331	2,502	'	'
Other current assets	296	312	'	'
Current assets of discontinued operations	'	'	'	'
Total current assets	9,152	8,581	'	'
Property, plant and equipment, net	4,160	4,104	'	'
Goodwill	'	'	'	'
Intangible assets, net	136	159	'	'
Restricted assets	'	'	'	'
Cost method investments	16,752	16,752	'	'
Investments in subsidiaries	-25,882	-36,006	'	'
Other non-current assets	13,316	13,874	'	'
Non-current assets of discontinued operations	'	'	'	'
Total non-current assets	8,482	-1,117	'	'
Intercompany receivable	538,820	543,291	'	'
Total assets	556,454	550,755	'	'
CURRENT LIABILITIES:	'	'	'	'
Current maturities of long-term debt and capital leases	86	84	'	'
Accounts payable	17,345	22,678	'	'
Accrued payroll and related expenses	701	1,212	'	'
Accrued interest	12,950	6,084	'	'
Current accrued capping, closure and post-closure costs	'	'	'	'
Other accrued liabilities	7,674	7,289	'	'
Total current liabilities	38,756	37,347	'	'
Long-term debt and capital leases, less current maturities	509,018	504,836	'	'
Accrued capping, closure and post-closure costs, less current portion	'	'	'	'
Deferred income taxes	6,956	6,954	'	'
Other long-term liabilities	9,501	10,025	'	'
STOCKHOLDERS' (DEFICIT) EQUITY:	'	'	'	'
Casella Waste Systems, Inc. stockholders (deficit)' equity	-7,777	-8,407	'	'
Noncontrolling interests	'	'	'	'
Total stockholders' (deficit) equity	-7,777	-8,407	'	'
Total liabilities and stockholders' (deficit) equity	556,454	550,755	'	'
Guarantor [Member]	'	'	'	'
CURRENT ASSETS:	'	'	'	'
Cash and cash equivalents	261	271	299	253
Restricted cash	76	76	'	'
Accounts receivable - trade, net	58,769	51,983	'	'
Refundable income taxes	'	'	'	'
Prepaid expenses	4,710	4,557	'	'
Inventory	4,151	3,852	'	'
Deferred income taxes	'	'	'	'
Other current assets	1,011	936	'	'
Current assets of discontinued operations	365	359	'	'
Total current assets	69,343	62,034	'	'
Property, plant and equipment, net	398,497	398,670	'	'
Goodwill	119,139	119,139	'	'
Intangible assets, net	12,597	13,261	'	'
Restricted assets	703	681	'	'
Cost method investments	1,932	1,932	'	'
Investments in subsidiaries	'	'	'	'
Other non-current assets	10,371	10,331	'	'
Non-current assets of discontinued operations	1,377	1,471	'	'
Total non-current assets	544,616	545,485	'	'
Intercompany receivable	-501,875	-506,348	'	'
Total assets	112,084	101,171	'	'
CURRENT LIABILITIES:	'	'	'	'
Current maturities of long-term debt and capital leases	791	801	'	'
Accounts payable	29,562	28,286	'	'
Accrued payroll and related expenses	3,900	4,849	'	'
Accrued interest	5	3	'	'
Current accrued capping, closure and post-closure costs	4,666	7,309	'	'
Other accrued liabilities	12,098	10,081	'	'
Total current liabilities	51,022	51,329	'	'
Long-term debt and capital leases, less current maturities	2,174	2,298	'	'
Accrued capping, closure and post-closure costs, less current portion	38,809	37,306	'	'
Deferred income taxes	'	'	'	'
Other long-term liabilities	7,166	7,149	'	'
STOCKHOLDERS' (DEFICIT) EQUITY:	'	'	'	'
Casella Waste Systems, Inc. stockholders (deficit)' equity	12,913	3,089	'	'
Noncontrolling interests	'	'	'	'
Total stockholders' (deficit) equity	12,913	3,089	'	'
Total liabilities and stockholders' (deficit) equity	112,084	101,171	'	'
Non-Guarantor [Member]	'	'	'	'
CURRENT ASSETS:	'	'	'	'
Cash and cash equivalents	342	42	300	242
Restricted cash	'	'	'	'
Accounts receivable - trade, net	12	86	'	'
Refundable income taxes	'	'	'	'
Prepaid expenses	9	2	'	'
Inventory	40	53	'	'
Deferred income taxes	'	'	'	'
Other current assets	7	7	'	'
Current assets of discontinued operations	'	'	'	'
Total current assets	410	190	'	'
Property, plant and equipment, net	649	650	'	'
Goodwill	'	'	'	'
Intangible assets, net	'	'	'	'
Restricted assets	'	'	'	'
Cost method investments	'	'	'	'
Investments in subsidiaries	'	'	'	'
Other non-current assets	'	'	'	'
Non-current assets of discontinued operations	'	'	'	'
Total non-current assets	649	650	'	'
Intercompany receivable	-38,877	-38,875	'	'
Total assets	-37,818	-38,035	'	'
CURRENT LIABILITIES:	'	'	'	'
Current maturities of long-term debt and capital leases	'	'	'	'
Accounts payable	465	824	'	'
Accrued payroll and related expenses	1	1	'	'
Accrued interest	'	'	'	'
Current accrued capping, closure and post-closure costs	3	3	'	'
Other accrued liabilities	228	242	'	'
Total current liabilities	697	1,070	'	'
Long-term debt and capital leases, less current maturities	'	'	'	'
Accrued capping, closure and post-closure costs, less current portion	37	36	'	'
Deferred income taxes	'	'	'	'
Other long-term liabilities	82	84	'	'
STOCKHOLDERS' (DEFICIT) EQUITY:	'	'	'	'
Casella Waste Systems, Inc. stockholders (deficit)' equity	-38,795	-39,095	'	'
Noncontrolling interests	161	-130	'	'
Total stockholders' (deficit) equity	-38,634	-39,225	'	'
Total liabilities and stockholders' (deficit) equity	-37,818	-38,035	'	'
Elimination [Member]	'	'	'	'
CURRENT ASSETS:	'	'	'	'
Cash and cash equivalents	'	'	'	'
Restricted cash	'	'	'	'
Accounts receivable - trade, net	'	'	'	'
Refundable income taxes	'	'	'	'
Prepaid expenses	'	'	'	'
Inventory	'	'	'	'
Deferred income taxes	'	'	'	'
Other current assets	'	'	'	'
Current assets of discontinued operations	'	'	'	'
Total current assets	'	'	'	'
Property, plant and equipment, net	'	'	'	'
Goodwill	'	'	'	'
Intangible assets, net	'	'	'	'
Restricted assets	'	'	'	'
Cost method investments	-1,932	-1,932	'	'
Investments in subsidiaries	25,882	36,006	'	'
Other non-current assets	'	'	'	'
Non-current assets of discontinued operations	'	'	'	'
Total non-current assets	23,950	34,074	'	'
Intercompany receivable	1,932	1,932	'	'
Total assets	25,882	36,006	'	'
CURRENT LIABILITIES:	'	'	'	'
Current maturities of long-term debt and capital leases	'	'	'	'
Accounts payable	'	'	'	'
Accrued payroll and related expenses	'	'	'	'
Accrued interest	'	'	'	'
Current accrued capping, closure and post-closure costs	'	'	'	'
Other accrued liabilities	'	'	'	'
Total current liabilities	'	'	'	'
Long-term debt and capital leases, less current maturities	'	'	'	'
Accrued capping, closure and post-closure costs, less current portion	'	'	'	'
Deferred income taxes	'	'	'	'
Other long-term liabilities	'	'	'	'
STOCKHOLDERS' (DEFICIT) EQUITY:	'	'	'	'
Casella Waste Systems, Inc. stockholders (deficit)' equity	25,882	36,006	'	'
Noncontrolling interests	'	'	'	'
Total stockholders' (deficit) equity	25,882	36,006	'	'
Total liabilities and stockholders' (deficit) equity	$25,882	$36,006	'	'

Subsidiary_Guarantors_Schedule1

Subsidiary Guarantors - Schedule of Consolidating Statement of Operations (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013
Condensed Financial Statements, Captions [Line Items]	'	'
Revenues	$141,387	$128,558
Operating expenses:	'	'
Cost of operations	98,766	88,419
General and administration	16,840	15,078
Depreciation and amortization	16,368	15,197
Expense from divestiture, acquisition and financing costs	'	20
Environmental remediation charge	75	'
Severance and reorganization costs	'	107
Total operating expenses	132,049	118,821
Operating income (loss)	9,338	9,737
Other expense (income), net:	'	'
Interest income	-88	-12
Interest expense	9,551	9,359
(Income) loss from equity method investments	'	977
(Gain) loss on derivative instruments	-69	-654
Other income	-192	-138
Other expense, net	9,202	9,532
Income (loss) from continuing operations before income taxes	136	205
Provision (benefit) for income taxes	290	319
Income (loss) from continuing operations	-154	-114
Discontinued operations:	'	'
Income (loss) from discontinued operations, net	'	329
Gain (loss) on disposal of discontinued operations, net	'	-378
Net loss	-154	-163
Less: Net income (loss) attributable to noncontrolling interests	136	28
Net income (loss) attributable to common stockholders	-290	-191
Parent [Member]	'	'
Condensed Financial Statements, Captions [Line Items]	'	'
Revenues	'	'
Operating expenses:	'	'
Cost of operations	17	'
General and administration	380	157
Depreciation and amortization	195	214
Expense from divestiture, acquisition and financing costs	'	'
Environmental remediation charge	'	'
Severance and reorganization costs	'	'
Total operating expenses	592	371
Operating income (loss)	-592	-371
Other expense (income), net:	'	'
Interest income	'	-1
Interest expense	9,589	9,347
(Income) loss from equity method investments	-10,089	-9,172
(Gain) loss on derivative instruments	-69	-654
Other income	-23	-19
Other expense, net	-592	-499
Income (loss) from continuing operations before income taxes	'	128
Provision (benefit) for income taxes	290	319
Income (loss) from continuing operations	'	-191
Discontinued operations:	'	'
Income (loss) from discontinued operations, net	'	'
Gain (loss) on disposal of discontinued operations, net	'	'
Net loss	-290	-191
Less: Net income (loss) attributable to noncontrolling interests	'	'
Net income (loss) attributable to common stockholders	-290	-191
Guarantor [Member]	'	'
Condensed Financial Statements, Captions [Line Items]	'	'
Revenues	141,090	127,693
Operating expenses:	'	'
Cost of operations	98,718	87,782
General and administration	16,470	14,927
Depreciation and amortization	16,173	14,802
Expense from divestiture, acquisition and financing costs	'	20
Environmental remediation charge	75	'
Severance and reorganization costs	'	107
Total operating expenses	131,436	117,638
Operating income (loss)	9,654	10,055
Other expense (income), net:	'	'
Interest income	-88	-11
Interest expense	-38	12
(Income) loss from equity method investments	'	-20
(Gain) loss on derivative instruments	'	'
Other income	-169	-118
Other expense, net	-295	-137
Income (loss) from continuing operations before income taxes	9,949	10,192
Provision (benefit) for income taxes	'	'
Income (loss) from continuing operations	'	10,192
Discontinued operations:	'	'
Income (loss) from discontinued operations, net	'	329
Gain (loss) on disposal of discontinued operations, net	'	-378
Net loss	9,949	10,143
Less: Net income (loss) attributable to noncontrolling interests	'	'
Net income (loss) attributable to common stockholders	9,949	10,143
Non-Guarantor [Member]	'	'
Condensed Financial Statements, Captions [Line Items]	'	'
Revenues	297	865
Operating expenses:	'	'
Cost of operations	31	637
General and administration	-10	-6
Depreciation and amortization	'	181
Expense from divestiture, acquisition and financing costs	'	'
Environmental remediation charge	'	'
Severance and reorganization costs	'	'
Total operating expenses	21	812
Operating income (loss)	276	53
Other expense (income), net:	'	'
Interest income	'	'
Interest expense	'	'
(Income) loss from equity method investments	'	997
(Gain) loss on derivative instruments	'	'
Other income	'	-1
Other expense, net	'	996
Income (loss) from continuing operations before income taxes	276	-943
Provision (benefit) for income taxes	'	'
Income (loss) from continuing operations	'	-943
Discontinued operations:	'	'
Income (loss) from discontinued operations, net	'	'
Gain (loss) on disposal of discontinued operations, net	'	'
Net loss	276	-943
Less: Net income (loss) attributable to noncontrolling interests	136	28
Net income (loss) attributable to common stockholders	140	-971
Elimination [Member]	'	'
Condensed Financial Statements, Captions [Line Items]	'	'
Revenues	'	'
Operating expenses:	'	'
Cost of operations	'	'
General and administration	'	'
Depreciation and amortization	'	'
Expense from divestiture, acquisition and financing costs	'	'
Environmental remediation charge	'	'
Severance and reorganization costs	'	'
Total operating expenses	'	'
Operating income (loss)	'	'
Other expense (income), net:	'	'
Interest income	'	'
Interest expense	'	'
(Income) loss from equity method investments	10,089	9,172
(Gain) loss on derivative instruments	'	'
Other income	'	'
Other expense, net	10,089	9,172
Income (loss) from continuing operations before income taxes	-10,089	-9,172
Provision (benefit) for income taxes	'	'
Income (loss) from continuing operations	'	-9,172
Discontinued operations:	'	'
Income (loss) from discontinued operations, net	'	'
Gain (loss) on disposal of discontinued operations, net	'	'
Net loss	-10,089	-9,172
Less: Net income (loss) attributable to noncontrolling interests	'	'
Net income (loss) attributable to common stockholders	($10,089)	($9,172)

Subsidiary_Guarantors_Schedule2

Subsidiary Guarantors - Schedule of Consolidating Statement of Comprehensive Income (Loss) (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013
Condensed Financial Statements, Captions [Line Items]	'	'
Net income (loss)	($154)	($163)
Other comprehensive income (loss), net of tax:	'	'
Unrealized gain (loss) resulting from changes in fair value of derivative instruments	'	-289
Unrealized gain (loss) resulting from changes in fair value of marketable securities	12	'
Realized loss (gain) on derivative instruments reclassified into earnings	'	164
Other comprehensive income (loss), net of tax	12	-125
Comprehensive income (loss)	-142	-288
Less: Comprehensive income (loss) attributable to noncontrolling interests	136	28
Comprehensive income (loss) attributable to common stockholders	-278	-316
Parent [Member]	'	'
Condensed Financial Statements, Captions [Line Items]	'	'
Net income (loss)	-290	-191
Other comprehensive income (loss), net of tax:	'	'
Unrealized gain (loss) resulting from changes in fair value of derivative instruments	'	'
Unrealized gain (loss) resulting from changes in fair value of marketable securities	'	'
Realized loss (gain) on derivative instruments reclassified into earnings	'	'
Other comprehensive income (loss), net of tax	'	'
Comprehensive income (loss)	-290	-191
Less: Comprehensive income (loss) attributable to noncontrolling interests	'	'
Comprehensive income (loss) attributable to common stockholders	-290	-191
Guarantor [Member]	'	'
Condensed Financial Statements, Captions [Line Items]	'	'
Net income (loss)	9,949	10,143
Other comprehensive income (loss), net of tax:	'	'
Unrealized gain (loss) resulting from changes in fair value of derivative instruments	'	'
Unrealized gain (loss) resulting from changes in fair value of marketable securities	12	'
Realized loss (gain) on derivative instruments reclassified into earnings	'	'
Other comprehensive income (loss), net of tax	12	'
Comprehensive income (loss)	9,961	10,143
Less: Comprehensive income (loss) attributable to noncontrolling interests	'	'
Comprehensive income (loss) attributable to common stockholders	9,961	10,143
Non-Guarantor [Member]	'	'
Condensed Financial Statements, Captions [Line Items]	'	'
Net income (loss)	276	-943
Other comprehensive income (loss), net of tax:	'	'
Unrealized gain (loss) resulting from changes in fair value of derivative instruments	'	-289
Unrealized gain (loss) resulting from changes in fair value of marketable securities	'	'
Realized loss (gain) on derivative instruments reclassified into earnings	'	164
Other comprehensive income (loss), net of tax	'	-125
Comprehensive income (loss)	276	-1,068
Less: Comprehensive income (loss) attributable to noncontrolling interests	136	28
Comprehensive income (loss) attributable to common stockholders	140	-1,096
Elimination [Member]	'	'
Condensed Financial Statements, Captions [Line Items]	'	'
Net income (loss)	-10,089	-9,172
Other comprehensive income (loss), net of tax:	'	'
Unrealized gain (loss) resulting from changes in fair value of derivative instruments	'	'
Unrealized gain (loss) resulting from changes in fair value of marketable securities	'	'
Realized loss (gain) on derivative instruments reclassified into earnings	'	'
Other comprehensive income (loss), net of tax	'	'
Comprehensive income (loss)	-10,089	-9,172
Less: Comprehensive income (loss) attributable to noncontrolling interests	'	'
Comprehensive income (loss) attributable to common stockholders	($10,089)	($9,172)

Subsidiary_Guarantors_Schedule3

Subsidiary Guarantors - Schedule of Condensed Consolidating Statement of Cash Flows (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Jul. 31, 2014	Jul. 31, 2013
Condensed Financial Statements, Captions [Line Items]	'	'
Net cash provided by (used in) operating activities	$13,581	$19,526
Cash Flows from Investing Activities:	'	'
Acquisitions, net of cash acquired	'	-29
Additions to property, plant and equipment	-16,881	-13,407
Payments on landfill operating lease contracts	-962	-1,982
Payments related to investments	'	-2,148
Proceeds from sale of property and equipment	163	284
Net cash provided by (used in) investing activities	-17,725	-18,354
Cash Flows from Financing Activities:	'	'
Proceeds from long-term borrowings	38,300	29,890
Principal payments on long-term debt	-34,314	-29,310
Payments of financing costs	-1	-359
Proceeds from the exercise of share based awards	143	'
Excess tax benefit on the vesting of share based awards	59	-63
Intercompany borrowings	'	'
Net cash provided by (used in) financing activities	4,187	158
Net cash provided by (used in) discontinued operations	88	-166
Net increase (decrease) in cash and cash equivalents	131	1,164
Cash and cash equivalents, beginning of period	2,464	1,755
Cash and cash equivalents, end of period	2,595	2,919
Parent [Member]	'	'
Condensed Financial Statements, Captions [Line Items]	'	'
Net cash provided by (used in) operating activities	-9,238	-6,951
Cash Flows from Investing Activities:	'	'
Acquisitions, net of cash acquired	'	'
Additions to property, plant and equipment	-227	-237
Payments on landfill operating lease contracts	'	'
Payments related to investments	'	-2,148
Proceeds from sale of property and equipment	'	'
Net cash provided by (used in) investing activities	-227	-2,385
Cash Flows from Financing Activities:	'	'
Proceeds from long-term borrowings	'	29,890
Principal payments on long-term debt	-34,181	-28,585
Payments of financing costs	-1	-359
Proceeds from the exercise of share based awards	'	'
Excess tax benefit on the vesting of share based awards	59	-63
Intercompany borrowings	43,429	9,513
Net cash provided by (used in) financing activities	9,306	10,396
Net cash provided by (used in) discontinued operations	'	'
Net increase (decrease) in cash and cash equivalents	-159	1,060
Cash and cash equivalents, beginning of period	2,151	1,260
Cash and cash equivalents, end of period	1,992	2,320
Guarantor [Member]	'	'
Condensed Financial Statements, Captions [Line Items]	'	'
Net cash provided by (used in) operating activities	22,829	26,358
Cash Flows from Investing Activities:	'	'
Acquisitions, net of cash acquired	'	-29
Additions to property, plant and equipment	-16,654	-13,109
Payments on landfill operating lease contracts	-962	-1,982
Payments related to investments	-310	'
Proceeds from sale of property and equipment	163	284
Net cash provided by (used in) investing activities	-17,808	-15,908
Cash Flows from Financing Activities:	'	'
Proceeds from long-term borrowings	38,300	'
Principal payments on long-term debt	-133	-725
Payments of financing costs	'	'
Proceeds from the exercise of share based awards	143	'
Excess tax benefit on the vesting of share based awards	'	'
Intercompany borrowings	-43,429	-9,513
Net cash provided by (used in) financing activities	-5,119	-10,238
Net cash provided by (used in) discontinued operations	88	-166
Net increase (decrease) in cash and cash equivalents	-10	46
Cash and cash equivalents, beginning of period	271	253
Cash and cash equivalents, end of period	261	299
Non-Guarantor [Member]	'	'
Condensed Financial Statements, Captions [Line Items]	'	'
Net cash provided by (used in) operating activities	-10	119
Cash Flows from Investing Activities:	'	'
Acquisitions, net of cash acquired	'	'
Additions to property, plant and equipment	'	-61
Payments on landfill operating lease contracts	'	'
Payments related to investments	310	'
Proceeds from sale of property and equipment	'	'
Net cash provided by (used in) investing activities	310	-61
Cash Flows from Financing Activities:	'	'
Proceeds from long-term borrowings	'	'
Principal payments on long-term debt	'	'
Payments of financing costs	'	'
Proceeds from the exercise of share based awards	'	'
Excess tax benefit on the vesting of share based awards	'	'
Intercompany borrowings	'	'
Net cash provided by (used in) financing activities	'	'
Net cash provided by (used in) discontinued operations	'	'
Net increase (decrease) in cash and cash equivalents	300	58
Cash and cash equivalents, beginning of period	42	242
Cash and cash equivalents, end of period	342	300
Acquisition [Member]	'	'
Cash Flows from Investing Activities:	'	'
Additions to property, plant and equipment	-45	-1,072
Acquisition [Member] | Parent [Member]	'	'
Cash Flows from Investing Activities:	'	'
Additions to property, plant and equipment	'	'
Acquisition [Member] | Guarantor [Member]	'	'
Cash Flows from Investing Activities:	'	'
Additions to property, plant and equipment	-45	-1,072
Acquisition [Member] | Non-Guarantor [Member]	'	'
Cash Flows from Investing Activities:	'	'
Additions to property, plant and equipment	'	'
Elimination [Member]	'	'
Condensed Financial Statements, Captions [Line Items]	'	'
Net cash provided by (used in) operating activities	'	'
Cash Flows from Investing Activities:	'	'
Acquisitions, net of cash acquired	'	'
Additions to property, plant and equipment	'	'
Payments on landfill operating lease contracts	'	'
Payments related to investments	'	'
Proceeds from sale of property and equipment	'	'
Net cash provided by (used in) investing activities	'	'
Cash Flows from Financing Activities:	'	'
Proceeds from long-term borrowings	'	'
Principal payments on long-term debt	'	'
Payments of financing costs	'	'
Proceeds from the exercise of share based awards	'	'
Excess tax benefit on the vesting of share based awards	'	'
Intercompany borrowings	'	'
Net cash provided by (used in) financing activities	'	'
Net cash provided by (used in) discontinued operations	'	'
Net increase (decrease) in cash and cash equivalents	'	'
Cash and cash equivalents, beginning of period	'	'
Cash and cash equivalents, end of period	'	'
Elimination [Member] | Acquisition [Member]	'	'
Cash Flows from Investing Activities:	'	'
Additions to property, plant and equipment	'	'