Annual salary commitments under employment agreements.

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Contingencies And Commitments [Line Items]

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Contract extension period.

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Amount of loss recognized in the period associated with the settlement of a future obligation associated with the termination of a contract.

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No definition available.

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Years of salary and bonus due to employee upon change in control or involuntary termination without cause.

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The number of executive officers that we have employment contracts with.

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Fuel Replacement Fee

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- Definition

Initial term of employment agreements.

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- Definition

Percentage participation in onsite remediation activities.

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Acreage of scrap yard owned by WSI.

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- Definition

Amount of future payments associated with a litigation settlement and the settlement of a future obligation associated with the termination of a contract.

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No definition available.

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Estimated undiscounted remediation costs.

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No definition available.

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Rate applied to the undiscounted amount of environmental loss contingencies to arrive at the present value recorded as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

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Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

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Amount of loss contingency liability.

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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-Name Accounting Standards Codification
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Cash payments to lessor's for use of assets under operating leases.

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Commitments and Contingencies - Additional Information (Detail)	8 Months Ended	12 Months Ended
	Dec. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) a Executives	Apr. 30, 2014 USD ($)	Apr. 30, 2013 USD ($)	Jan. 29, 2016	Apr. 30, 2011 USD ($)	May. 31, 2009 USD ($)
Contingencies And Commitments [Line Items]
Total rent expense under operating leases charged to operations	$ 4,868,000	$ 9,392,000	$ 5,651,000	$ 5,372,000
Contract settlement charge		$ 1,940,000
Number of executive officers \| Executives		4
Contract extension period		1 year
Total annual commitments for salaries		$ 1,425,000
Greenwood Street Landfill [Member]
Contingencies And Commitments [Line Items]
Litigation settlement		129,000
Greenwood Street Landfill [Member] \| Administrative Penalty [Member]
Contingencies And Commitments [Line Items]
Litigation settlement		172,000
Expera Old Town LLC [Member]
Contingencies And Commitments [Line Items]
Reserve related with settlement		2,616,000
Contract settlement charge		1,940,000
Reserve for legal costs		75,000
upon execution of SA [Member] \| Expera Old Town LLC [Member]
Contingencies And Commitments [Line Items]
Litigation settlement		1,250,000
Five years following execution of SA [Member] \| Expera Old Town LLC [Member]
Contingencies And Commitments [Line Items]
Litigation settlement		350,000
Operating Expense [Member] \| Expera Old Town LLC [Member]
Contingencies And Commitments [Line Items]
Reserve related with settlement		676,000
Maximum [Member]
Contingencies And Commitments [Line Items]
Operating facilities and equipment under operating leases		$ 36,000
Initial term of employment contract		3 years
Intangible assets, useful life		10 years
Salary and bonuses payment range		3 years
Maximum [Member] \| Expera Old Town LLC [Member]
Contingencies And Commitments [Line Items]
Fuel replacement fee		$ 2,000,000
Maximum [Member] \| Employment Contracts [Member]
Contingencies And Commitments [Line Items]
Intangible assets, useful life		2 years
Minimum [Member]
Contingencies And Commitments [Line Items]
Initial term of employment contract		1 year
Intangible assets, useful life		5 years
Salary and bonuses payment range		1 year
Minimum [Member] \| Employment Contracts [Member]
Contingencies And Commitments [Line Items]
Intangible assets, useful life		1 year
Potsdam Environmental Remediation Liability [Member]
Contingencies And Commitments [Line Items]
Scrap yard and solid waste transfer station \| a		25
Estimate of total undiscounted costs associated with implementing the preferred remedies						$ 12,130,000	$ 10,219,000
Risk free interest rate		1.80%
Potsdam Environmental Remediation Liability [Member] \| Subsequent Event [Member]
Contingencies And Commitments [Line Items]
Remediation activities, participant share percentage					15.00%