Fair Value Measurements - Fair Values of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Financial assets:
Securities available-for-sale	$ 128,049	$ 97,566
Securities held-to-maturity	0	20,154
Carrying Value
Financial assets:
Interest-bearing deposits in other financial institutions	289,348	128,420
Securities available-for-sale	128,049	97,566
Securities held-to-maturity		20,154
Loans held-for-sale	4,102	1,975
Net loans held-for-investment	1,533,341	1,436,451
FHLB and other restricted stock	8,447	8,345
Accrued interest receivable	9,498	5,136
Financial liabilities:
Deposits	1,646,930	1,479,307
FHLB advances	130,000	20,000
Accrued interest payable	3,886	6,004
Fair Value
Financial assets:
Interest-bearing deposits in other financial institutions	289,348	128,420
Securities available-for-sale	128,049	97,566
Securities held-to-maturity		20,480
Loans held-for-sale	4,188	2,102
Net loans held-for-investment	1,543,212	1,449,383
Accrued interest receivable	9,498	5,136
Financial liabilities:
Deposits	1,673,664	1,468,540
FHLB advances	130,442	20,092
Accrued interest payable	3,886	6,004
Fair Value | Quoted Prices in Active Markets for Identical Assets (Level 1)
Financial assets:
Interest-bearing deposits in other financial institutions	289,348	128,420
Securities available-for-sale	0	0
Securities held-to-maturity		0
Loans held-for-sale	0	0
Net loans held-for-investment	0	0
Accrued interest receivable	10	78
Financial liabilities:
Deposits	0	0
FHLB advances	0	0
Accrued interest payable	0	0
Fair Value | Significant Other Observable Inputs (Level 2)
Financial assets:
Interest-bearing deposits in other financial institutions	0	0
Securities available-for-sale	128,049	97,566
Securities held-to-maturity		20,480
Loans held-for-sale	4,188	2,102
Net loans held-for-investment	0	0
Accrued interest receivable	359	375
Financial liabilities:
Deposits	0	0
FHLB advances	130,442	20,092
Accrued interest payable	2	1
Fair Value | Significant Unobservable Inputs (Level 3)
Financial assets:
Interest-bearing deposits in other financial institutions	0	0
Securities available-for-sale	0	0
Securities held-to-maturity		0
Loans held-for-sale	0	0
Net loans held-for-investment	1,543,212	1,449,383
Accrued interest receivable	9,129	4,683
Financial liabilities:
Deposits	1,673,664	1,468,540
FHLB advances	0	0
Accrued interest payable	$ 3,884	$ 6,003