- Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at January 1,	$ 19,096	$ 25,001
Gross increases for tax positions of prior years	6,586	1,935
Gross increases for tax positions of current year	2,522	2,397
Decreases due to settlements and other prior year tax positions	(2,550)	(10,338)
Currency translation effect on foreign balances	(143)
Currency translation effect on foreign balances		101
Balance at December 31,	25,511	19,096
Reserves related to potential interest at December 31,	3,090	1,018
Unrecognized tax benefits at December 31,	$ 28,601	$ 20,114

Amount recognized for uncertainty in income taxes classified as noncurrent.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from foreign currency translation.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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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 foreign currency translation.

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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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