Commitments and Contingencies Sublease Income, Leased Facilities (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Commitments and Contingencies Disclosure [Abstract] | |||
| Operating Leases, Income Statement, Sublease Revenue | $ 2.1 | $ 1.3 | $ 0.0 |
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- References No definition available.
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- Definition The amount of revenue recognized for the period under subleasing arrangements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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