Loans and Allowance for Loan and Lease Losses - Summary of Activity in ALLL (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Allowance for Loan and Lease Losses
Balance at beginning of period	$ 17,520	$ 11,514	$ 13,611	$ 13,506
Charge offs	(2,249)	(127)	(4,562)	(5,825)
Recoveries	45	87	67	493
Provision	2,850	0	9,050	3,300
Balance at end of period	18,166	11,474	18,166	11,474
Commercial
Allowance for Loan and Lease Losses
Balance at beginning of period	11,218	6,895	8,883	8,071
Charge offs	(2,229)	(103)	(4,478)	(5,772)
Recoveries	42	82	60	483
Provision	2,456	(65)	7,022	4,027
Balance at end of period	11,487	6,809	11,487	6,809
Real  Estate
Allowance for Loan and Lease Losses
Balance at beginning of period	4,368	2,709	2,897	3,643
Charge offs	0	0	0	0
Recoveries	0	0	0	0
Provision	365	81	1,836	(853)
Balance at end of period	4,733	2,790	4,733	2,790
Construction and land development loans
Allowance for Loan and Lease Losses
Balance at beginning of period	55	295	34	426
Charge offs	0	0	0	0
Recoveries	0	0	0	0
Provision	22	(176)	43	(307)
Balance at end of period	77	119	77	119
Consumer  and Single Family Mortgages
Allowance for Loan and Lease Losses
Balance at beginning of period	1,879	1,486	1,797	1,290
Charge offs	(20)	(24)	(84)	(53)
Recoveries	3	5	7	10
Provision	7	289	149	509
Balance at end of period	1,869	1,756	1,869	1,756
Unallocated
Allowance for Loan and Lease Losses
Balance at beginning of period	0	129	0	76
Charge offs	0	0	0	0
Recoveries	0	0	0	0
Provision	0	(129)	0	(76)
Balance at end of period	$ 0	$ 0	$ 0	$ 0