Derivative Instruments and Hedge Activities - Summary of Amounts Included in Non-Interest Income in Consolidated Statements of Operations Relating to Derivative Instruments not Designated in Hedging Relationship (Details) - Non-interest Expense - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Derivative [Line Items]
Amounts relating to derivative instruments, not designated in hedging relationship	$ 116	$ (154)	$ (635)	$ (530)
Other Credit Derivatives
Derivative [Line Items]
Amounts relating to derivative instruments, not designated in hedging relationship	3	66	(8)	62
Other Interest Rate Derivatives
Derivative [Line Items]
Amounts relating to derivative instruments, not designated in hedging relationship	$ 113	$ (220)	$ (627)	$ (592)