Allowance for Credit Losses - Activity in Allowance for Credit Losses (Details) - USD ($) $ in Thousands		12 Months Ended
	Jan. 01, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 35,154	$ 35,154	$ 32,423	$ 27,122
Initial Allowance on PCD Loans Acquired During the Period		6,279
Provision for credit losses		37,779	10,999	11,730
Charge- Offs		(9,842)	(10,559)	(8,026)
Recoveries		2,251	2,420	1,789
TDR Allowance Adjustments		(114)	(129)	(192)
Ending Balance		92,733	35,154	32,423
Provision for credit losses on accrued interest receivable		400
Construction and land development
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	1,842	1,842	2,233	1,642
Initial Allowance on PCD Loans Acquired During the Period		87
Provision for credit losses		1,399	(421)	564
Charge- Offs		0	0	0
Recoveries		114	31	27
TDR Allowance Adjustments		(1)	(1)	0
Ending Balance		4,920	1,842	2,233
Commercial real estate - owner occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	5,361	5,361
Initial Allowance on PCD Loans Acquired During the Period		1,161
Provision for credit losses		3,632
Charge- Offs		(310)
Recoveries		18
TDR Allowance Adjustments		(74)
Ending Balance		9,868	5,361
Commercial real estate - non-owner occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	7,863	7,863
Initial Allowance on PCD Loans Acquired During the Period		2,236
Provision for credit losses		18,966
Charge- Offs		(177)
Recoveries		37
TDR Allowance Adjustments		0
Ending Balance		38,266	7,863
Commercial real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	13,224	13,224	11,112	9,285
Provision for credit losses			1,677	4,736
Charge- Offs			(248)	(3,139)
Recoveries			744	292
TDR Allowance Adjustments			(61)	(62)
Ending Balance			13,224	11,112
Residential real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	7,667	7,667	7,775	7,131
Initial Allowance on PCD Loans Acquired During the Period		124
Provision for credit losses		3,840	(231)	29
Charge- Offs		(240)	(152)	(80)
Recoveries		350	338	816
TDR Allowance Adjustments		(28)	(63)	(121)
Ending Balance		17,500	7,667	7,775
Commercial and financial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	9,716	9,716	8,585	7,297
Initial Allowance on PCD Loans Acquired During the Period		2,643
Provision for credit losses		8,329	7,969	4,359
Charge- Offs		(7,091)	(7,550)	(3,396)
Recoveries		1,416	712	325
TDR Allowance Adjustments		0	0	0
Ending Balance		18,690	9,716	8,585
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	2,705	2,705	2,718	1,767
Initial Allowance on PCD Loans Acquired During the Period		28
Provision for credit losses		1,613	2,005	2,042
Charge- Offs		(2,024)	(2,609)	(1,411)
Recoveries		316	595	329
TDR Allowance Adjustments		(11)	(4)	(9)
Ending Balance		3,489	2,705	$ 2,718
Paycheck Protection Program
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	0	0
Initial Allowance on PCD Loans Acquired During the Period		0
Provision for credit losses		0
Charge- Offs		0
Recoveries		0
TDR Allowance Adjustments		0
Ending Balance		0	0
Cumulative Effect Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	21,226	21,226
Initial Allowance on PCD Loans Acquired During the Period	700
Ending Balance	21,226		21,226
Cumulative Effect Adjustment | Construction and land development
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	1,479	1,479
Ending Balance			1,479
Cumulative Effect Adjustment | Commercial real estate - owner occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	80	80
Ending Balance			80
Cumulative Effect Adjustment | Commercial real estate - non-owner occupied
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	9,341	9,341
Ending Balance			9,341
Cumulative Effect Adjustment | Residential real estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	5,787	5,787
Ending Balance			5,787
Cumulative Effect Adjustment | Commercial and financial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	3,677	3,677
Ending Balance			3,677
Cumulative Effect Adjustment | Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	862	862
Ending Balance			862
Cumulative Effect Adjustment | Paycheck Protection Program
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 0	$ 0
Ending Balance			$ 0