Accrued expenses and other current liabilities - Changes to Withholding Tax Reserve (Details) - Historical Tax Withholding Possible Loss - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Loss Contingency Accrual [Roll Forward]
Balance, beginning of period	$ 17,036	$ 22,166
Amounts charged to (released from) expense	(1,343)	168
Net payments and settlements	0	0
Balance, end of period	$ 15,693	$ 22,334

Amount of loss contingency liability.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

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- Definition

Amount of cash outflow reducing loss contingency liability.

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- Definition

Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

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- Definition

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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