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Divestiture Transactions - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Apr. 30, 2013	Mar. 31, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Divestiture transactions	$ (4,935,000)
Remaining divestiture costs			$ 18,660,000	$ 17,765,000
Proceeds from sale of assets	4,550,000
Casella-Altela Regional Environmental Services, LLC [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Divestiture transactions	2,850,000
Membership interest			51.00%
Proceeds from sale of assets	3,500,000
Casella-Altela Regional Environmental Services, LLC [Member] | Discontinued Operations, Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Divestiture transactions	928,000
Proceeds from sale of assets	$ 1,050,000
Altela, Inc. [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Membership interest	49.00%
Maine Energy Facility [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Undiscounted purchase consideration		$ 6,650,000
Undiscounted purchase consideration paid in installments		21 years
Divestiture transactions	$ 1,157
Remaining divestiture costs			$ 0

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The aggregate amount of (gains), losses and charges associated with the disposal of an asset group or an individually significant group of assets that does not constitute a disposal group. This includes any gain or loss on disposal of the asset group, as well as any impairment charge related to the asset group that was subsequently disposed of.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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