Loss contingency damages sought estimated value.

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Amount before tax of (gain) loss recognized for the (reversal of write-down) write-down to fair value, less cost to sell, of a discontinued operation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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Business Dispositions (Narrative) (Details) - USD ($) $ in Thousands			12 Months Ended
	Feb. 28, 2017	Apr. 23, 2014	Dec. 31, 2018	Dec. 31, 2017
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Provision to reduce net assets, discontinued operation			$ 14,110
Estimated surety bond claim, including associated expenses				$ 20,900
Surety Bond [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Aggregate demolition surety performance bond	$ 20,000
NASDI, LLC and Yankee Environmental Services, LLC
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Proceeds from divestiture of businesses		$ 5,309