Loans and Allowance for Credit Losses - Risk category of loans by class of loans (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Loans and Leases Receivable Disclosure [Line Items]
Prior	$ 2,082,365	$ 1,628,363
Four years before current fiscal year	1,020,597	723,156
Three before current fiscal year	1,394,229	1,227,254
Two years before current fiscal year	1,104,601	1,549,098
Fiscal year before current fiscal year	1,196,584	1,193,110
Current fiscal year	461,182	1,439,231
Total	7,259,558	7,760,212
Commercial
Loans and Leases Receivable Disclosure [Line Items]
Prior	491,592	378,211
Four years before current fiscal year	228,709	124,696
Three before current fiscal year	217,024	279,475
Two years before current fiscal year	147,486	239,474
Fiscal year before current fiscal year	175,769	178,334
Current fiscal year	98,577	237,243
Total	1,359,157	1,437,433
Commercial | Pass
Loans and Leases Receivable Disclosure [Line Items]
Prior	445,359	323,660
Four years before current fiscal year	206,252	111,886
Three before current fiscal year	194,852	249,541
Two years before current fiscal year	136,249	211,551
Fiscal year before current fiscal year	163,994	164,166
Current fiscal year	96,633	227,095
Total	1,243,339	1,287,899
Commercial | Watch
Loans and Leases Receivable Disclosure [Line Items]
Prior	32,128	31,903
Four years before current fiscal year	11,393	5,315
Three before current fiscal year	16,407	19,145
Two years before current fiscal year	6,720	21,013
Fiscal year before current fiscal year	10,750	7,740
Current fiscal year	1,944	7,979
Total	79,342	93,095
Commercial | Special Mention
Loans and Leases Receivable Disclosure [Line Items]
Prior	1,384	4,969
Four years before current fiscal year	10,386	1,692
Three before current fiscal year	3,346	8,969
Two years before current fiscal year	3,977	3,385
Fiscal year before current fiscal year	900	5,599
Current fiscal year		2,169
Total	19,993	26,783
Commercial | Substandard
Loans and Leases Receivable Disclosure [Line Items]
Prior	12,721	17,679
Four years before current fiscal year	678	5,803
Three before current fiscal year	2,419	1,820
Two years before current fiscal year	540	3,525
Fiscal year before current fiscal year	125	829
Total	16,483	29,656
PPP loans
Loans and Leases Receivable Disclosure [Line Items]
Fiscal year before current fiscal year	198,313
Current fiscal year	39,728	454,771
Total	238,041	454,771
PPP loans | Pass
Loans and Leases Receivable Disclosure [Line Items]
Fiscal year before current fiscal year	198,313
Current fiscal year	39,728	454,771
Total	238,041	454,771
Income producing - commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Prior	995,299	772,050
Four years before current fiscal year	373,914	411,658
Three before current fiscal year	705,402	494,245
Two years before current fiscal year	676,405	717,011
Fiscal year before current fiscal year	538,737	745,454
Current fiscal year	244,300	546,582
Total	3,534,057	3,687,000
Income producing - commercial real estate | Pass
Loans and Leases Receivable Disclosure [Line Items]
Prior	713,318	560,915
Four years before current fiscal year	267,101	347,946
Three before current fiscal year	654,340	397,953
Two years before current fiscal year	574,668	622,276
Fiscal year before current fiscal year	503,679	643,388
Current fiscal year	244,300	512,387
Total	2,957,406	3,084,865
Income producing - commercial real estate | Watch
Loans and Leases Receivable Disclosure [Line Items]
Prior	156,867	152,367
Four years before current fiscal year	106,813	62,912
Three before current fiscal year		91,636
Two years before current fiscal year	44,223	89,852
Fiscal year before current fiscal year	34,620	44,555
Current fiscal year		34,195
Total	342,523	475,517
Income producing - commercial real estate | Special Mention
Loans and Leases Receivable Disclosure [Line Items]
Prior	57,361	213
Three before current fiscal year	42,544
Two years before current fiscal year	51,972
Fiscal year before current fiscal year		51,969
Total	151,877	52,182
Income producing - commercial real estate | Substandard
Loans and Leases Receivable Disclosure [Line Items]
Prior	67,753	58,555
Four years before current fiscal year		800
Three before current fiscal year	8,518	4,656
Two years before current fiscal year	5,542	4,883
Fiscal year before current fiscal year	438	5,542
Total	82,251	74,436
Owner occupied - commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Prior	456,184	388,031
Four years before current fiscal year	138,264	106,067
Three before current fiscal year	227,618	116,544
Two years before current fiscal year	101,686	232,140
Fiscal year before current fiscal year	48,755	104,424
Current fiscal year	19,429	50,488
Total	991,936	997,694
Owner occupied - commercial real estate | Pass
Loans and Leases Receivable Disclosure [Line Items]
Prior	403,599	343,371
Four years before current fiscal year	133,224	100,272
Three before current fiscal year	132,309	111,996
Two years before current fiscal year	65,422	136,644
Fiscal year before current fiscal year	46,712	59,681
Current fiscal year	19,429	49,584
Total	800,695	801,548
Owner occupied - commercial real estate | Watch
Loans and Leases Receivable Disclosure [Line Items]
Prior	26,454	16,014
Four years before current fiscal year	3,254	5,011
Three before current fiscal year	11,982	2,640
Two years before current fiscal year	8,783	10,338
Fiscal year before current fiscal year	2,043	15,501
Total	52,516	49,504
Owner occupied - commercial real estate | Special Mention
Loans and Leases Receivable Disclosure [Line Items]
Prior	355	418
Three before current fiscal year	81,634
Two years before current fiscal year	19,084	83,110
Fiscal year before current fiscal year		19,091
Total	101,073	102,619
Owner occupied - commercial real estate | Substandard
Loans and Leases Receivable Disclosure [Line Items]
Prior	25,776	28,228
Four years before current fiscal year	1,786	784
Three before current fiscal year	1,693	1,908
Two years before current fiscal year	8,397	2,048
Fiscal year before current fiscal year		10,151
Current fiscal year		904
Total	37,652	44,023
Real estate mortgage - residential
Loans and Leases Receivable Disclosure [Line Items]
Prior	21,157	19,504
Four years before current fiscal year	10,160	5,090
Three before current fiscal year	13,430	10,199
Two years before current fiscal year	16,922	13,474
Fiscal year before current fiscal year	4,789	18,209
Current fiscal year	10,673	10,116
Total	77,131	76,592
Real estate mortgage - residential | Pass
Loans and Leases Receivable Disclosure [Line Items]
Prior	18,663	16,310
Four years before current fiscal year	10,160	2,693
Three before current fiscal year	13,430	10,199
Two years before current fiscal year	16,922	12,746
Fiscal year before current fiscal year	4,789	18,209
Current fiscal year	10,673	10,116
Total	74,637	70,273
Real estate mortgage - residential | Watch
Loans and Leases Receivable Disclosure [Line Items]
Prior	598	1,996
Four years before current fiscal year	0	699
Two years before current fiscal year		728
Total	598	3,423
Real estate mortgage - residential | Substandard
Loans and Leases Receivable Disclosure [Line Items]
Prior	1,896	1,198
Four years before current fiscal year		1,698
Total	1,896	2,896
Construction - commercial and residential
Loans and Leases Receivable Disclosure [Line Items]
Prior	64,245	22,231
Four years before current fiscal year	260,874	60,486
Three before current fiscal year	202,852	309,745
Two years before current fiscal year	118,601	303,823
Fiscal year before current fiscal year	148,352	105,679
Current fiscal year	40,809	71,297
Total	835,733	873,261
Construction - commercial and residential | Pass
Loans and Leases Receivable Disclosure [Line Items]
Prior	64,042	21,290
Four years before current fiscal year	204,514	60,486
Three before current fiscal year	198,089	266,788
Two years before current fiscal year	118,410	297,480
Fiscal year before current fiscal year	148,352	105,679
Current fiscal year	40,809	71,297
Total	774,216	823,020
Construction - commercial and residential | Watch
Loans and Leases Receivable Disclosure [Line Items]
Prior	203	929
Four years before current fiscal year	56,360
Three before current fiscal year	1,295	42,751
Two years before current fiscal year		3,448
Total	57,858	47,128
Construction - commercial and residential | Special Mention
Loans and Leases Receivable Disclosure [Line Items]
Prior		12
Two years before current fiscal year		2,895
Total		2,907
Construction - commercial and residential | Substandard
Loans and Leases Receivable Disclosure [Line Items]
Three before current fiscal year	3,468	206
Two years before current fiscal year	191
Total	3,659	206
Construction - C&I (owner occupied)
Loans and Leases Receivable Disclosure [Line Items]
Prior	22,289	11,975
Four years before current fiscal year	2,380	10,476
Three before current fiscal year	26,072	8,755
Two years before current fiscal year	39,734	35,275
Fiscal year before current fiscal year	70,024	36,645
Current fiscal year	688	55,779
Total	161,187	158,905
Construction - C&I (owner occupied) | Pass
Loans and Leases Receivable Disclosure [Line Items]
Prior	17,572	8,278
Four years before current fiscal year	1,979	10,476
Three before current fiscal year	20,373	6,637
Two years before current fiscal year	24,552	30,340
Fiscal year before current fiscal year	54,309	22,209
Current fiscal year	688	40,101
Total	119,473	118,041
Construction - C&I (owner occupied) | Watch
Loans and Leases Receivable Disclosure [Line Items]
Prior	4,607	3,573
Four years before current fiscal year	401
Three before current fiscal year	5,699	2,118
Two years before current fiscal year		4,935
Total	10,707	10,626
Construction - C&I (owner occupied) | Special Mention
Loans and Leases Receivable Disclosure [Line Items]
Prior		124
Fiscal year before current fiscal year		14,436
Current fiscal year		15,678
Total		30,238
Construction - C&I (owner occupied) | Substandard
Loans and Leases Receivable Disclosure [Line Items]
Prior	110
Two years before current fiscal year	15,182
Fiscal year before current fiscal year	15,715
Total	31,007
Home equity
Loans and Leases Receivable Disclosure [Line Items]
Prior	30,091	35,425
Four years before current fiscal year	6,241	4,493
Three before current fiscal year	1,773	8,227
Two years before current fiscal year	3,690	7,827
Fiscal year before current fiscal year	11,819	4,271
Current fiscal year	6,945	12,924
Total	60,559	73,167
Home equity | Pass
Loans and Leases Receivable Disclosure [Line Items]
Prior	28,213	33,226
Four years before current fiscal year	6,241	4,493
Three before current fiscal year	1,773	8,227
Two years before current fiscal year	3,642	7,827
Fiscal year before current fiscal year	11,819	4,224
Current fiscal year	6,945	12,924
Total	58,633	70,921
Home equity | Watch
Loans and Leases Receivable Disclosure [Line Items]
Prior	1,314	1,596
Total	1,314	1,596
Home equity | Substandard
Loans and Leases Receivable Disclosure [Line Items]
Prior	564	603
Two years before current fiscal year	48
Fiscal year before current fiscal year		47
Total	612	650
Other consumer
Loans and Leases Receivable Disclosure [Line Items]
Prior	1,508	936
Four years before current fiscal year	55	190
Three before current fiscal year	58	64
Two years before current fiscal year	77	74
Fiscal year before current fiscal year	26	94
Current fiscal year	33	31
Total	1,757	1,389
Other consumer | Pass
Loans and Leases Receivable Disclosure [Line Items]
Prior	1,502	929
Four years before current fiscal year	55	190
Three before current fiscal year	58	64
Two years before current fiscal year	77	74
Fiscal year before current fiscal year	26	94
Current fiscal year	33	31
Total	1,751	1,382
Other consumer | Substandard
Loans and Leases Receivable Disclosure [Line Items]
Prior	6	7
Total	$ 6	$ 7