Derivatives and Hedging Activities - Gains and losses recognized in income on derivatives not designated as hedging instruments (Details) - Not designated as hedging instrument - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	$ 383	$ 340
Customer derivatives and dealer offsets | Other noninterest income
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	1,424	503
Bifurcated embedded derivatives and dealer offsets | Other noninterest income
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	(195)	218
De-designated hedges | Other noninterest income
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	0	(193)
Mortgage banking derivatives | Mortgage loan revenue
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	(829)	(190)
Risk participations | Other noninterest income
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	$ (17)	$ 2