Income Taxes - Change in the Balance of Gross Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning of the period balance	$ 9,961	$ 10,741	$ 11,616
Increases related to tax positions taken during a prior period	10	19	503
Decreases related to tax positions taken during the prior period	(6)	(1,257)	(1,782)
Increases related to tax positions taken during the current period	9,282	870	805
Decreases related to settlements	0	0	0
Decreases related to expiration of statute of limitations	(2,472)	(412)	(401)
End of the period balance	$ 16,775	$ 9,961	$ 10,741

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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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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