Income Taxes - Reconciliation of Beginning and Ending Balance of Total Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of beginning and ending balance of total unrecognized tax benefits
Balance, beginning period	$ 27,591	$ 27,648	$ 18,440
Gross increases - tax positions in prior year	1,516	3,721	398
Gross decreases - tax positions in prior period	0	(2,896)	0
Gross increases - tax positions in current period	7,682	5,796	8,810
Lapse of statute of limitations	0	(1,078)	0
Settlements	0	(5,600)	0
Balance, end of period	$ 36,789	$ 27,591	$ 27,648

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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Amount of decrease 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 settlements with taxing authorities.

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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.

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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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