Derivative Instruments and Hedging Activities - Additional Information (Details)			3 Months Ended		9 Months Ended
	Jul. 28, 2020 USD ($) Derivative	Jun. 24, 2016	Sep. 30, 2020 USD ($) Derivative	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) Loan Derivative	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Derivative Instruments and Hedging Activities [Abstract]
Frequency of repricing					3 months
Interest expense			$ 49,000	$ 51,000	$ 148,000	$ 149,000
Notional/contract amount	$ 1,200,000
Termination fee	$ 89,200
Number of swap agreements terminated | Derivative	1
Interest Rate Swaps - Junior Subordinated Debt Due 2036 [Member]
Derivative Instruments and Hedging Activities [Abstract]
Fixed interest rate			3.21%	3.21%	3.21%	3.21%
Interest expense			$ 28,000	$ 9,000	$ 69,000	$ 20,000
Interest Rate Swaps - Junior Subordinated Debt Due 2036 [Member] | LIBOR [Member]
Derivative Instruments and Hedging Activities [Abstract]
Term of variable rate					3 months
Basis spread on variable rate			1.70%		1.70%
Interest Rate Swaps - Junior Subordinated Debt Due 2036 [Member] | Maximum [Member]
Derivative Instruments and Hedging Activities [Abstract]
Period to convert floating rate liability to fixed rate liability under agreement		2031
Interest Rate Swaps - Junior Subordinated Debt Due 2036 [Member] | Minimum [Member]
Derivative Instruments and Hedging Activities [Abstract]
Period to convert floating rate liability to fixed rate liability under agreement		2020
Interest Rate Swap [Member]
Derivative Instruments and Hedging Activities [Abstract]
Expiration date					Sep. 15, 2020
Cash collateral			$ 1,100,000		$ 1,100,000		$ 730,000
Interest Rate Swaps - Commercial Loans [Member]
Derivative Instruments and Hedging Activities [Abstract]
Number of swap agreements | Derivative			2		2
Number of commercial loans managed with swap agreements | Loan					2
Interest income				$ 7,000		$ 25,000
Interest expense			$ 19,000		$ 37,000
Interest Rate Swaps - Commercial Loans [Member] | LIBOR [Member]
Derivative Instruments and Hedging Activities [Abstract]
Term of variable rate					1 month
Interest Rate Swaps - Commercial Loans [Member] | Maximum [Member]
Derivative Instruments and Hedging Activities [Abstract]
Period to convert fixed rate assets to floating rate assets under agreement					2025
Interest Rate Swaps - Commercial Loans [Member] | Minimum [Member]
Derivative Instruments and Hedging Activities [Abstract]
Period to convert fixed rate assets to floating rate assets under agreement					2022