Income Taxes (Narrative) (Details) - USD ($) $ in Thousands |
9 Months Ended | 12 Months Ended |
|---|---|---|
Sep. 30, 2018 |
Dec. 31, 2017 |
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| Income Tax Disclosure [Abstract] | ||
| Gross unrecognized tax benefits | $ 18,307 | $ 18,312 |
| Unrecognized tax benefits, exclusive of interest and penalties, recorded as a non-current liability | 4,054 | 4,622 |
| Unrecognized tax benefits that would impact effective tax rate, if recognized | 9,544 | |
| Potential interest and penalties related to unrecognized tax benefits included in income tax expense | (221) | 1,261 |
| Accrued interest and penalties on unrecognized tax benefits | $ 5,463 | $ 6,018 |
| X | ||||||||||
- Definition Represents the amount of unrecognized tax benefits, exclusive of interest and penalties, recorded as a non-current liability. No definition available.
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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 accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the 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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