Income Taxes Unrecognized tax expense (benefit) roll forward (Details) - USD ($) $ in Thousands |
12 Months Ended | |||
|---|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
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| Income Tax Disclosure [Abstract] | ||||
| Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions | $ 3,037 | $ 2,025 | $ 2,585 | |
| Unrecognized Tax Benefits, Increase Resulting from Acquisition | 37,090 | 13,733 | ||
| Unrecognized Tax Benefits | 63,100 | 23,417 | 26,053 | $ 10,808 |
| Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions | 458 | $ 4,661 | $ (1,073) | |
| Unrecognized Tax Benefits that Would Impact Effective Tax Rate | $ 50,600 | |||
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- References No definition available.
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in unrecognized tax benefits resulting from acquisitions. No definition available.
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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