Fair value measurement - Gains and losses (realized and unrealized) included in earnings for level 3 assets and liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation Abstract
Gain (loss) included in earnings	$ 9,336	$ (10,318)	$ (42,115)
Changes in unrealized gains (losses) included in earnings relating to assets still held	11,943	6,364	(19,300)
Mortgage banking activities
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation Abstract
Gain (loss) included in earnings	166	(10,216)	(42,055)
Changes in unrealized gains (losses) included in earnings relating to assets still held	11,964	6,410	(19,327)
Trading account (loss) profit
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation Abstract
Gain (loss) included in earnings	(71)	(102)	(60)
Changes in unrealized gains (losses) included in earnings relating to assets still held	(21)	(46)	27
Other operating income
Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation Abstract
Gain (loss) included in earnings	9,241	0	0
Changes in unrealized gains (losses) included in earnings relating to assets still held	$ 0	$ 0	$ 0