Derivative Instruments - Amounts and Locations of Activity Related to Interest Rate Swaps Designated as Cash Flow Hedges within Corporation's Consolidated Balance Sheet and Statement of Income (Details) - Interest Rate Swaps - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Derivative [Line Items]
Interest rate contracts	$ 50	$ (4)	$ 134	$ (333)
Accrued interest and other liabilities
Derivative [Line Items]
Accrued interest and other liabilities	(598)		(598)		$ (768)
Interest expense – subordinated notes and debentures
Derivative [Line Items]
Other income	(62)	(65)	(131)	(86)
Other income
Derivative [Line Items]
Other income	$ 0	$ 0	$ 0	$ 0