Derivative instruments and hedging activities - Effect Of Derivative Instruments On Consolidated Statements Of Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivatives designated as hedging instruments
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in OCI on Derivative	$ 4,243	$ (9,530)	$ 18,604	$ (10,128)
Gain or (Loss) Reclassified from Accumulated OCI into Income	(976)	(380)	(5,392)	2,429
Derivatives designated as hedging instruments \| Foreign exchange contracts - forwards \| Net sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Reclassified from Accumulated OCI into Income	(815)	334	(5,249)	5,594
Derivatives designated as hedging instruments \| Foreign exchange contracts - forwards \| Cost of sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Reclassified from Accumulated OCI into Income	(73)	(448)	(73)	(1,817)
Derivatives designated as hedging instruments \| Foreign exchange contracts - forwards \| Operating expenses
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Reclassified from Accumulated OCI into Income	(88)	(266)	(70)	(1,348)
Derivatives designated as hedging instruments \| Foreign Exchange Forward A
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in OCI on Derivative	7,400	(12,524)	23,098	(6,800)
Derivatives designated as hedging instruments \| Foreign Exchange Forward B
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in OCI on Derivative	(1,869)	1,849	(2,675)	(1,898)
Derivatives designated as hedging instruments \| Foreign Exchange Forward C
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in OCI on Derivative	(1,288)	1,145	(1,819)	(1,430)
Derivatives not designated as hedging instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(1,679)	(267)	(3,942)	(163)
Derivatives not designated as hedging instruments \| Foreign exchange contracts - forwards \| Other expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	$ (1,679)	$ (267)	$ (3,942)	$ (163)

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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