Schedule of Change in Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Income Tax Uncertainties [Abstract]
Unrecognized tax benefits at January 1, 2018 (as adjusted)	$ 3,444
Increase related to positions taken in prior period	314
Increase related to positions taken in current period	596
Decrease related to expiration of statute of limitations	(295)
Unrecognized tax benefits at December 31, 2018	4,059
Accrued interest	705	$ 600
Unrecognized tax benefits recorded in other long-term liabilities at December 31, 2018	$ 4,764

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Amount recognized for uncertainty in income taxes classified as noncurrent.

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Amount of unrecognized tax benefits.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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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 interest expense accrued for an underpayment of income taxes.

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

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