Derivative instruments and risk management - Location and Amount of Gains (Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses) recognized in net income	$ (11,849)	$ (3,318)	$ 18,043
Total net gains (losses) recognized in comprehensive income	$ (35)	$ (1,123)	$ 5,495
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Foreign exchange revenue	Foreign exchange revenue	Foreign exchange revenue
Spot and forward foreign exchange
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses) recognized in net income	$ (47)	$ 28	$ (131)
Currency swaps \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses) recognized in net income	(14,639)	(7,188)	23,531
Currency swaps \| Designated as Hedging Instrument \| Fair value hedges
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses) recognized in net income	2,837	3,842	(5,357)
Currency swaps \| Designated as Hedging Instrument \| Unrealized net gains (losses) on translation of net investment in foreign operations \| Net investment hedges
Derivative Instruments, Gain (Loss) [Line Items]
Total net gains (losses) recognized in comprehensive income	$ (35)	$ (1,123)	$ 5,495

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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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.

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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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