Loans - Risk Categories of Loans by Class of Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
2020	$ 923,194
2019	975,533
2018	885,466
2017	707,402
2016	662,295
Prior	1,039,260
Revolving	578,902
Total	5,772,052	$ 5,198,404
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	922,672
2019	971,272
2018	873,927
2017	693,075
2016	633,485
Prior	994,588
Revolving	564,537
Total	5,653,556	5,091,691
Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2020	397
2019	2,724
2018	1,698
2017	3,786
2016	15,829
Prior	10,315
Revolving	3,000
Total	37,749	51,560
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	148
2018	7,946
2017	4,060
2016	9,825
Prior	14,869
Revolving	6,357
Total	43,205	53,958
Substandard Impaired
Financing Receivable, Credit Quality Indicator [Line Items]
2020	125
2019	1,389
2018	1,895
2017	6,442
2016	2,835
Prior	19,488
Revolving	4,999
Total	37,173
Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	39
2016	321
Prior	0
Revolving	9
Total	369	1,195
Construction and land development
Financing Receivable, Credit Quality Indicator [Line Items]
2020	29,610
2019	96,052
2018	71,906
2017	35,172
2016	11,052
Prior	20,616
Revolving	34,427
Total	298,835	325,113
Construction and land development | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	29,412
2019	95,549
2018	70,528
2017	35,134
2016	10,478
Prior	18,260
Revolving	33,439
Total	292,800	317,765
Construction and land development | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2020	198
2019	503
2018	1,378
2017	38
2016	0
Prior	2,147
Revolving	0
Total	4,264	2,235
Construction and land development | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	58
Revolving	988
Total	1,046	5,113
Construction and land development | Substandard Impaired
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	574
Prior	151
Revolving	0
Total	725
Construction and land development | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving	0
Total	0	0
Commercial real estate - owner-occupied
Financing Receivable, Credit Quality Indicator [Line Items]
2020	74,503
2019	187,333
2018	158,516
2017	145,160
2016	164,586
Prior	330,600
Revolving	15,952
Total	1,076,650	1,000,000
Commercial real estate - owner-occupied | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	74,304
2019	185,717
2018	157,946
2017	139,936
2016	158,728
Prior	317,778
Revolving	15,952
Total	1,050,361
Commercial real estate - owner-occupied | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2020	199
2019	1,616
2018	0
2017	1,016
2016	4,471
Prior	4,088
Revolving	0
Total	11,390
Commercial real estate - owner-occupied | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	570
2017	3,782
2016	1,066
Prior	5,100
Revolving	0
Total	10,518
Commercial real estate - owner-occupied | Substandard Impaired
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	426
2016	0
Prior	3,634
Revolving	0
Total	4,060
Commercial real estate - owner-occupied | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	321
Prior	0
Revolving	0
Total	321
Commercial real estate - non owner-occupied
Financing Receivable, Credit Quality Indicator [Line Items]
2020	80,710
2019	321,949
2018	235,981
2017	131,813
2016	213,026
Prior	401,808
Revolving	7,500
Total	1,392,787
Commercial real estate - non owner-occupied | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	80,710
2019	321,844
2018	230,276
2017	130,437
2016	196,698
Prior	390,280
Revolving	6,150
Total	1,356,395
Commercial real estate - non owner-occupied | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	105
2018	0
2017	1,376
2016	7,876
Prior	1,117
Revolving	0
Total	10,474
Commercial real estate - non owner-occupied | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	5,705
2017	0
2016	8,326
Prior	6,367
Revolving	1,350
Total	21,748
Commercial real estate - non owner-occupied | Substandard Impaired
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	126
Prior	4,044
Revolving	0
Total	4,170
Commercial real estate - non owner-occupied | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving	0
Total	0
Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total		2,378,971
Commercial real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total		2,331,725
Commercial real estate | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total		26,827
Commercial real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total		20,098
Commercial real estate | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Total		321
Residential real estate
Financing Receivable, Credit Quality Indicator [Line Items]
2020	32,646
2019	160,940
2018	263,368
2017	278,163
2016	200,049
Prior	215,431
Revolving	317,574
Total	1,468,171	1,507,863
Residential real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	32,562
2019	160,057
2018	261,757
2017	273,829
2016	196,662
Prior	202,708
Revolving	312,596
Total	1,440,171	1,482,278
Residential real estate | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	190
2018	277
2017	721
2016	3,387
Prior	621
Revolving	68
Total	5,264	7,364
Residential real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	1,334
2017	0
2016	0
Prior	1,607
Revolving	1,580
Total	4,521	18,221
Residential real estate | Substandard Impaired
Financing Receivable, Credit Quality Indicator [Line Items]
2020	84
2019	693
2018	0
2017	3,613
2016	0
Prior	10,495
Revolving	3,330
Total	18,215
Residential real estate | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving	0
Total	0	0
Commercial and financial
Financing Receivable, Credit Quality Indicator [Line Items]
2020	100,094
2019	153,588
2018	117,202
2017	91,679
2016	47,067
Prior	57,469
Revolving	190,133
Total	757,232	778,252
Commercial and financial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	100,094
2019	152,509
2018	115,004
2017	88,448
2016	44,728
Prior	52,576
Revolving	185,175
Total	738,534	755,957
Commercial and financial | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	287
2018	14
2017	530
2016	95
Prior	2,255
Revolving	1,181
Total	4,362	11,925
Commercial and financial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	148
2018	337
2017	259
2016	425
Prior	1,698
Revolving	2,099
Total	4,966	9,496
Commercial and financial | Substandard Impaired
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	644
2018	1,847
2017	2,403
2016	1,819
Prior	940
Revolving	1,669
Total	9,322
Commercial and financial | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	39
2016	0
Prior	0
Revolving	9
Total	48	874
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
2020	29,181
2019	55,671
2018	38,493
2017	25,415
2016	26,515
Prior	13,336
Revolving	13,316
Total	201,927	208,205
Consumer | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	29,140
2019	55,596
2018	38,416
2017	25,291
2016	26,191
Prior	12,986
Revolving	11,225
Total	198,845	203,966
Consumer | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	23
2018	29
2017	105
2016	0
Prior	87
Revolving	1,751
Total	1,995	3,209
Consumer | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	19
2016	8
Prior	39
Revolving	340
Total	406	1,030
Consumer | Substandard Impaired
Financing Receivable, Credit Quality Indicator [Line Items]
2020	41
2019	52
2018	48
2017	0
2016	316
Prior	224
Revolving	0
Total	681
Consumer | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
2020	0
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving	0
Total	0	$ 0
Paycheck Protection Program
Financing Receivable, Credit Quality Indicator [Line Items]
2020	576,450
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving	0
Total	576,450
Paycheck Protection Program | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
2020	576,450
2019	0
2018	0
2017	0
2016	0
Prior	0
Revolving	0
Total	$ 576,450