Commitments and Contingencies - Surety Bonds (Details) - USD ($) $ in Millions |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Surety Bonds | ||
| Commitments and Contingencies | ||
| Loss contingency on certain claims | $ 36.1 | $ 30.6 |
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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. No definition available.
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- Definition Reflects the estimated amount of loss from the specified contingency as of the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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