Derivative Instruments - Gain (loss) recognized on derivatives instruments (Details) - Not designated as hedging - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Gain (loss) recognized on derivative instruments
Gain (loss) recognized on derivatives instruments	$ (1,530)	$ 1,581
Interest rate lock commitments | Mortgage banking
Gain (loss) recognized on derivative instruments
Gain (loss) recognized on derivatives instruments	1,227	1,789
Forward loan sales commitments | Mortgage banking
Gain (loss) recognized on derivative instruments
Gain (loss) recognized on derivatives instruments	666	246
TBA mortgage backed securities | Mortgage banking
Gain (loss) recognized on derivative instruments
Gain (loss) recognized on derivatives instruments	$ (3,423)	$ (454)