Fair Value - Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financial Assets:
Investment securities available-for-sale, at fair value	$ 11,006	$ 14,722
Carrying Value
Financial Assets:
Cash and cash equivalents	15,566	16,651
Investment securities available-for-sale, at fair value	11,006	14,722
Loans receivable held for sale		6,231
Loans receivable held for investment	397,847	355,556
Accrued interest receivable	1,223	1,143
Financial Liabilities:
Deposits	297,724	281,414
Federal Home Loan Bank advances	84,000	70,000
Junior subordinated debentures	4,335	5,100
Accrued interest payable	384	334
Fair Value
Financial Assets:
Cash and cash equivalents	15,566	16,651
Investment securities available-for-sale, at fair value	11,006	14,722
Loans receivable held for sale		6,270
Loans receivable held for investment	404,923	354,792
Accrued interest receivable	1,223	1,143
Financial Liabilities:
Deposits	289,629	269,418
Federal Home Loan Bank advances	84,997	69,933
Junior subordinated debentures	3,734	4,481
Accrued interest payable	384	334
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value
Financial Assets:
Cash and cash equivalents	15,566	16,651
Investment securities available-for-sale, at fair value		1,979
Accrued interest receivable	69	78
Significant Other Observable Inputs (Level 2) | Fair Value
Financial Assets:
Investment securities available-for-sale, at fair value	11,006	12,743
Loans receivable held for sale		6,270
Accrued interest receivable	22	43
Financial Liabilities:
Deposits	289,629	269,418
Federal Home Loan Bank advances	84,997	69,933
Accrued interest payable	377	324
Significant Unobservable Inputs (Level 3) | Fair Value
Financial Assets:
Loans receivable held for investment	404,923	354,792
Accrued interest receivable	1,132	1,022
Financial Liabilities:
Junior subordinated debentures	3,734	4,481
Accrued interest payable	$ 7	$ 10