Derivative Instruments and Hedging Activities - Amount of Gain or Loss Recognized in Income on Derivatives (Details) - Not Designated as Hedging Instruments - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Total Derivative (Loss)/Gain	$ (116)	$ 230	$ 58
Interest Rate Swap Contracts—Commercial Loans
Derivative Instruments, Gain (Loss) [Line Items]
Total Derivative (Loss)/Gain	(132)	145	17
Interest Rate Lock Commitments—Mortgage Loans
Derivative Instruments, Gain (Loss) [Line Items]
Total Derivative (Loss)/Gain	70	25	(11)
Forward Sale Contracts—Mortgage Loans
Derivative Instruments, Gain (Loss) [Line Items]
Total Derivative (Loss)/Gain	$ (54)	$ 60	$ 52