Fair Value - Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Carrying Value
Financial Assets:
Loans receivable held for sale	$ 1,079	$ 22,370
Loans receivable held for investment	368,991	334,851
Financial Liabilities:
Time Deposits	159,596	150,789
Federal Home Loan Bank advances	84,000	65,000
Junior subordinated debentures	5,100	5,100
Fair Value
Financial Assets:
Loans receivable held for sale	1,074	22,626
Loans receivable held for investment	365,379	333,231
Financial Liabilities:
Time Deposits	158,325	150,240
Federal Home Loan Bank advances	83,525	64,887
Junior subordinated debentures	4,503	4,503
Significant Other Observable Inputs (Level 2) | Fair Value
Financial Assets:
Loans receivable held for sale	1,074	22,626
Financial Liabilities:
Time Deposits	158,325	150,240
Federal Home Loan Bank advances	83,525	64,887
Junior subordinated debentures	4,503
Significant Unobservable Inputs (Level 3) | Fair Value
Financial Assets:
Loans receivable held for investment	$ 365,379	333,231
Financial Liabilities:
Junior subordinated debentures		$ 4,503