Derivative instruments and hedging activities - Non-hedging activities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Derivative Instruments, Gain (Loss) [Line Items]
Amount of net gain (loss) recognized in income on derivatives	$ 633	$ 1,512	$ 7,746
Forward contracts | Mortgage banking activities
Derivative Instruments, Gain (Loss) [Line Items]
Amount of net gain (loss) recognized in income on derivatives	34	655	8,094
Interest rate cap | Other operating income
Derivative Instruments, Gain (Loss) [Line Items]
Amount of net gain (loss) recognized in income on derivatives	18	(18)	0
Indexed options on deposits | Interest expense on deposits
Derivative Instruments, Gain (Loss) [Line Items]
Amount of net gain (loss) recognized in income on derivatives	7,423	6,201	(5,290)
Bifurcated embedded options | Interest expense on deposits
Derivative Instruments, Gain (Loss) [Line Items]
Amount of net gain (loss) recognized in income on derivatives	$ (6,842)	$ (5,326)	$ 4,942