Income Taxes - Schedule of Changes in Unrecognized Tax Benefit (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning Balance	$ 5,271	$ 3,036	$ 2,963
Additions for tax positions related to the current year	419	422	476
Additions for tax positions related to prior years	92	1,953	385
Reductions for tax positions related to prior years	(499)	(99)	(567)
Reductions for lapse of statute of limitations	0	(41)	(221)
Ending Balance	$ 5,283	$ 5,271	$ 3,036

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

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- Definition

Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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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.

+ References

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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