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Multiemployer plan (Details 2) - Multiemployer plans, pension [Member] - Operating Engineers Local 800 and WY Contractors Association Pension Plan for WY [Member] - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2015 | Sep. 30, 2016
Multiemployer Plans [Line Items] |  |
Additional multiemployer plan withdrawal obligation | $ 2.4 |
Multiemployer plans, withdrawal obligation |  | $ 16.4

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- Definition The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349 + Details
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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. + Details
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- Definition Amount of the obligation recognized by withdrawing from 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 No definition available. + Details
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- Details
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- Details
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