Multiemployer Plans, Collective-Bargaining Arrangement, Percentage Of Participants Expiring, Remainder Of Fiscal Year

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- Definition

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

+ References

No definition available.

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- Definition

Amount awarded to other party in judgment or settlement of litigation.

+ References

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- Definition

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

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=82911808&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14557-108349

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- Definition

Percentage of employee participants subject to a collective bargaining arrangement to all participants in a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 5
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947

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Commitments and Contingencies (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 1994	Sep. 30, 2018	Dec. 31, 2017
Loss Contingencies [Line Items]
Letter of credit amount outstanding		$ 32.7	$ 33.8
Collective-bargaining arrangement, percentage of participants		56.00%
Collective-bargaining arrangement, percentage of participants expiring in 2018		4.00%
Kansas Breach of Settlement Agreement
Loss Contingencies [Line Items]
Litigation settlement, awarded to other party	$ 58.7
Surety Bond
Loss Contingencies [Line Items]
Outstanding surety bond		$ 2.7	$ 2.7