Derivative Instruments and Hedging Activities - Net Losses Related to Derivatives Not Designated as Hedges (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Non-designated hedge interest rate swaps and credit derivatives
Other non-interest expense	$ 600	$ (468)	$ 2,105	$ (1,225)