Investment in Affordable Housing Projects - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Schedule Of Equity Method Investments [Line Items]
Year in which investments are expected to be paid			2023		2023
Tax credits and other benefits recognized			$ 350,000	$ 414,000
Losses from investments in affordable housing projects	$ 89,000	$ 47,000	317,000	$ 191,000
Other Assets [Member]
Schedule Of Equity Method Investments [Line Items]
Investments in affordable housing projects	3,900,000		3,900,000		$ 4,200,000
Other Liabilities [Member]
Schedule Of Equity Method Investments [Line Items]
Capital call for investments in affordable housing projects	$ 397,000		$ 397,000		$ 749,000