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Contingencies (Details)	9 Months Ended
	Sep. 30, 2016 USD ($) site
Commitments and Contingencies Disclosure [Abstract]
Number of Superfund sites for which company may be liable | site	1
Workers' compensation deductible (per occurrence)	$ 1,000,000
Workers' compensation accrued liability	19,000,000
Outstanding letters of credit	16,900,000
Estimate of possible loss	$ 0

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- Definition

Number Of Superfund Sites For Which Company May Be Liable

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Workers Compensation Deductible

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

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-Name Accounting Standards Codification
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-Section 50
-Paragraph 9
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Carrying value as of the balance sheet date of obligations and payables pertaining to claims incurred of a workers compensation nature.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(15)(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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