Income Taxes - Reconciliation of unrecognized tax benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Unrecognized income tax benefits [Rollforward]
Beginning of year	$ 7,401	$ 11,297	$ 5,469
Additions for tax provisions related to the current year	515	54	6,318
Reductions for tax positions related to the current year			(41)
Reductions for tax positions related to prior years	(113)	(3,941)
Additions for tax positions related to prior years	646		823
Reductions for settlements	(2,642)
Lapses of applicable statutes of limitation	(520)		(1,232)
Currency translation adjustment		(9)	(40)
Ending of year	$ 5,287	$ 7,401	$ 11,297

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.

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Amount of decrease 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 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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