Loans and Allowance for Loan Losses - Troubled Debt Restructurings That Are Not Performing (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020 loan	Jun. 30, 2019 loan	Jun. 30, 2020 USD ($) contract loan	Jun. 30, 2019 loan	Dec. 31, 2019 USD ($) contract
Number of contracts | loan	0	0	0	0
Nonperforming Financial Instruments [Member]
Number of contracts | contract			7		5
Recorded investment, not performing | $			$ 1,812		$ 1,344
One-To-Four Family - Mixed Used Property [Member] | Nonperforming Financial Instruments [Member]
Number of contracts | contract			1
Recorded investment, not performing | $			$ 338
Taxi Medallion Portfolio Segment [Member] | Nonperforming Financial Instruments [Member]
Number of contracts | contract			5		4
Recorded investment, not performing | $			$ 1,195		$ 1,065
Commercial Business and Other Portfolio Segment [Member] | Nonperforming Financial Instruments [Member]
Number of contracts | contract			1		1
Recorded investment, not performing | $			$ 279		$ 279