Derivatives and hedging activities - Effect of Derivative Instruments Not Designated as Hedging Instruments on the Statements of Income and Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Fee Income | Fee Income
Derivative Instruments, Gain (Loss)
Amount of Gain Recognized in Income	$ 652	$ 106
Derivatives not designated as hedging instruments
Derivative Instruments, Gain (Loss)
Amount of Gain Recognized in Income	(268)	521
Derivatives not designated as hedging instruments | Interest Rate Products | Other income / (expense)
Derivative Instruments, Gain (Loss)
Amount of Gain Recognized in Income	(262)	516
Derivatives not designated as hedging instruments | Other Contracts | Other income / (expense)
Derivative Instruments, Gain (Loss)
Amount of Gain Recognized in Income	$ (6)	$ 5