Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|---|
Sep. 30, 2018 |
Sep. 30, 2017 |
Sep. 30, 2018 |
Sep. 30, 2017 |
Dec. 31, 2017 |
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| Income Tax Disclosure [Abstract] | |||||
| Liability for unrecognized tax | $ 6,000 | $ 6,000 | $ 5,400 | ||
| Accrued interest and penalties applied to uncertain tax positions | 2,100 | $ 2,100 | |||
| Income tax expense (benefit) | $ 2,371 | $ 1,919 | $ 5,561 | $ 6,004 | |
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- References No definition available.
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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