Derivative instruments and hedging activities - Fair Value Of Derivative Instruments On Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Derivative assets	$ 10,453	$ 6,124
Derivative liability	(7,528)	(19,359)
Derivatives designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative assets	10,033	4,681
Derivative liability	(5,636)	(18,877)
Derivatives designated as hedging instruments \| Foreign exchange contracts - ST forwards \| Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative assets	6,118	1,564
Derivatives designated as hedging instruments \| Foreign exchange contracts - ST forwards \| Other current liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	(4,166)	(12,549)
Derivatives designated as hedging instruments \| Foreign exchange contracts - LT forwards \| Other long-term assets
Derivatives, Fair Value [Line Items]
Derivative assets	3,915	3,117
Derivatives designated as hedging instruments \| Foreign exchange contracts - LT forwards \| Other long-term liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	(1,470)	(6,328)
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative assets	420	1,443
Derivative liability	(1,892)	(482)
Derivatives not designated as hedging instruments \| Foreign exchange contracts - ST forwards \| Prepaid expenses and other current assets
Derivatives, Fair Value [Line Items]
Derivative assets	420	1,443
Derivatives not designated as hedging instruments \| Foreign exchange contracts - ST forwards \| Other current liabilities
Derivatives, Fair Value [Line Items]
Derivative liability	$ (1,892)	$ (482)

Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, not subject to a master netting arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226052-175313

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- Definition

Fair value of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226052-175313

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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