Income Taxes - Uncertain tax position liabilities (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance, January 1	$ 5,300	$ 4,810
Increases related to prior period tax positions	96	338
Decrease related to prior year tax positions	(815)
Increase related to tax positions from acquired companies	1,587
Settlements	(3,776)
Foreign currency transaction gains/losses	351
Balance, September 30	$ 2,743	$ 5,148

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.

+ References

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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 acquisitions.

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