Accounting for Uncertainty in Income Taxes - Additional Information (Detail) - USD ($) $ in Millions |
9 Months Ended | 12 Months Ended |
|---|---|---|
Sep. 30, 2017 |
Dec. 31, 2016 |
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| Income Tax Disclosure [Abstract] | ||
| Liability for unrecognized tax | $ 5.3 | $ 4.6 |
| Unrecognized tax favorable impact on effective tax rate | 4.6 | |
| Accrued interest and penalties applied to uncertain tax positions | $ 2.1 | $ 1.9 |
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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 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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| X | ||||||||||
- 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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