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Loans and Allowance for Credit Losses - Schedule of Risk Rating and Payment Performance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Risk Category Of Loans [Line Items]
Total loans	$ 36,285,887	$ 32,991,927
Writeoff, by Origination Year
Current fiscal year	3,667	1,114
Fiscal year before current fiscal year	17,871	10,423
Two years before current fiscal year	15,857	30,346
Three years before current fiscal year	11,184	3,274
Four years before current fiscal year	5,052	8,604
Prior	14,405	10,411
Revolving	3,268	4,291
Total	71,304	68,463	$ 27,281
Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Total loans	36,285,887	32,991,927
Commercial
Risk Category Of Loans [Line Items]
Total loans	10,288,560	9,512,230
Writeoff, by Origination Year
Total	36,172	41,451	6,885
Commercial | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	1,931,760	1,873,630
Originated one year before current year	1,440,650	1,719,159
Originated two years before current year	1,286,788	1,039,832
Originated three years before current year	777,990	600,282
Originated four years before current year	497,232	489,693
Originated more than five years before current fiscal year	673,411	583,939
Revolving	2,752,900	2,214,453
Revolving to Term	695,528	758,478
Total loans	10,056,259	9,279,466
Writeoff, by Origination Year
Current fiscal year	2,892	0
Fiscal year before current fiscal year	13,447	6,475
Two years before current fiscal year	11,797	24,022
Three years before current fiscal year	2,074	120
Four years before current fiscal year	4,061	7,245
Prior	923	2,880
Revolving	978	709
Total	36,172	41,451
Commercial real estate
Risk Category Of Loans [Line Items]
Total loans	16,307,486	14,140,629
Writeoff, by Origination Year
Total	18,565	11,198	6,519
Commercial real estate | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	2,326,885	2,279,487
Originated one year before current year	2,652,462	3,664,419
Originated two years before current year	4,252,908	2,695,350
Originated three years before current year	2,269,851	1,636,367
Originated four years before current year	1,464,609	1,163,055
Originated more than five years before current fiscal year	1,911,188	1,350,392
Revolving	123,704	107,225
Revolving to Term	1,131,441	1,075,276
Total loans	16,133,048	13,971,571
Writeoff, by Origination Year
Current fiscal year	70	0
Fiscal year before current fiscal year	204	54
Two years before current fiscal year	84	2,808
Three years before current fiscal year	6,570	2,144
Four years before current fiscal year	2	0
Prior	11,635	6,192
Revolving	0	0
Total	18,565	11,198
BBCC
Writeoff, by Origination Year
Total	1,801	1,650	85
BBCC | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	81,807	81,840
Originated one year before current year	80,974	65,503
Originated two years before current year	57,703	46,152
Originated three years before current year	35,437	39,072
Originated four years before current year	30,912	28,622
Originated more than five years before current fiscal year	24,293	21,170
Revolving	72,005	70,966
Revolving to Term	23,608	48,497
Total loans	406,739	401,822
Writeoff, by Origination Year
Current fiscal year	0	670
Fiscal year before current fiscal year	1,184	548
Two years before current fiscal year	410	362
Three years before current fiscal year	56	70
Four years before current fiscal year	112	0
Prior	39	0
Revolving	0	0
Total	1,801	1,650
Residential real estate
Risk Category Of Loans [Line Items]
Originated in current fiscal year	510,184	453,859
Originated one year before current year	481,758	1,513,234
Originated two years before current year	1,466,295	1,840,082
Originated three years before current year	1,668,493	1,708,506
Originated four years before current year	1,580,169	434,861
Originated more than five years before current fiscal year	1,090,373	748,622
Revolving	43	0
Revolving to Term	271	279
Total loans	6,797,586	6,699,443
Writeoff, by Origination Year
Current fiscal year	0	0
Fiscal year before current fiscal year	0	0
Two years before current fiscal year	0	0
Three years before current fiscal year	0	0
Four years before current fiscal year	0	0
Prior	14	256
Revolving	0	0
Total	14	256	344
Residential real estate | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Total loans	6,797,586	6,699,443
Residential real estate | Performing
Risk Category Of Loans [Line Items]
Originated in current fiscal year	509,704	453,743
Originated one year before current year	476,698	1,508,671
Originated two years before current year	1,455,085	1,836,078
Originated three years before current year	1,662,195	1,705,131
Originated four years before current year	1,574,961	430,783
Originated more than five years before current fiscal year	1,058,175	722,987
Revolving	43	0
Revolving to Term	271	279
Total loans	6,737,132	6,657,672
Residential real estate | Nonperforming
Risk Category Of Loans [Line Items]
Originated in current fiscal year	480	116
Originated one year before current year	5,060	4,563
Originated two years before current year	11,210	4,004
Originated three years before current year	6,298	3,375
Originated four years before current year	5,208	4,078
Originated more than five years before current fiscal year	32,198	25,635
Revolving	0	0
Revolving to Term	0	0
Total loans	60,454	41,771
Indirect
Risk Category Of Loans [Line Items]
Originated in current fiscal year	439,549	393,741
Originated one year before current year	281,057	357,294
Originated two years before current year	229,189	163,942
Originated three years before current year	93,601	83,418
Originated four years before current year	38,310	38,285
Originated more than five years before current fiscal year	15,072	14,106
Revolving	0	0
Revolving to Term	0	196
Total loans	1,096,778	1,050,982
Writeoff, by Origination Year
Current fiscal year	426	271
Fiscal year before current fiscal year	2,426	1,447
Two years before current fiscal year	1,660	787
Three years before current fiscal year	687	159
Four years before current fiscal year	127	152
Prior	284	132
Revolving	0	0
Total	5,610	2,948	2,525
Indirect | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Total loans	1,096,778	1,050,982
Indirect | Performing
Risk Category Of Loans [Line Items]
Originated in current fiscal year	438,835	393,369
Originated one year before current year	279,910	355,822
Originated two years before current year	227,691	162,735
Originated three years before current year	92,223	82,871
Originated four years before current year	37,937	37,967
Originated more than five years before current fiscal year	14,810	13,815
Revolving	0	0
Revolving to Term	0	196
Total loans	1,091,406	1,046,775
Indirect | Nonperforming
Risk Category Of Loans [Line Items]
Originated in current fiscal year	714	372
Originated one year before current year	1,147	1,472
Originated two years before current year	1,498	1,207
Originated three years before current year	1,378	547
Originated four years before current year	373	318
Originated more than five years before current fiscal year	262	291
Revolving	0	0
Revolving to Term	0	0
Total loans	5,372	4,207
Direct
Risk Category Of Loans [Line Items]
Originated in current fiscal year	83,869	109,439
Originated one year before current year	73,151	90,841
Originated two years before current year	66,928	93,008
Originated three years before current year	61,669	48,947
Originated four years before current year	34,627	29,869
Originated more than five years before current fiscal year	81,918	71,001
Revolving	108,573	75,204
Revolving to Term	3,409	4,863
Total loans	514,144	523,172
Writeoff, by Origination Year
Current fiscal year	279	173
Fiscal year before current fiscal year	610	1,899
Two years before current fiscal year	1,906	2,367
Three years before current fiscal year	1,763	746
Four years before current fiscal year	750	1,207
Prior	1,074	543
Revolving	2,290	3,582
Total	8,672	10,517	10,799
Direct | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Total loans	514,144	523,172
Direct | Performing
Risk Category Of Loans [Line Items]
Originated in current fiscal year	83,773	109,372
Originated one year before current year	72,838	90,310
Originated two years before current year	66,563	92,491
Originated three years before current year	61,317	48,387
Originated four years before current year	34,159	29,659
Originated more than five years before current fiscal year	80,188	67,129
Revolving	108,572	75,080
Revolving to Term	3,327	4,852
Total loans	510,737	517,280
Direct | Nonperforming
Risk Category Of Loans [Line Items]
Originated in current fiscal year	96	67
Originated one year before current year	313	531
Originated two years before current year	365	517
Originated three years before current year	352	560
Originated four years before current year	468	210
Originated more than five years before current fiscal year	1,730	3,872
Revolving	1	124
Revolving to Term	82	11
Total loans	3,407	5,892
Home equity
Risk Category Of Loans [Line Items]
Originated in current fiscal year	0	290
Originated one year before current year	0	474
Originated two years before current year	1,537	488
Originated three years before current year	301	544
Originated four years before current year	1,344	1,420
Originated more than five years before current fiscal year	15,925	8,810
Revolving	1,218,820	1,022,233
Revolving to Term	43,406	31,212
Total loans	1,281,333	1,065,471
Writeoff, by Origination Year
Current fiscal year	0	0
Fiscal year before current fiscal year	0	0
Two years before current fiscal year	0	0
Three years before current fiscal year	34	35
Four years before current fiscal year	0	0
Prior	436	408
Revolving	0	0
Total	470	443	$ 124
Home equity | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Total loans	1,281,333	1,065,471
Home equity | Performing
Risk Category Of Loans [Line Items]
Originated in current fiscal year	0	290
Originated one year before current year	0	164
Originated two years before current year	259	160
Originated three years before current year	210	140
Originated four years before current year	1,135	679
Originated more than five years before current fiscal year	11,005	4,483
Revolving	1,216,226	1,019,389
Revolving to Term	31,787	23,918
Total loans	1,260,622	1,049,223
Home equity | Nonperforming
Risk Category Of Loans [Line Items]
Originated in current fiscal year	0	0
Originated one year before current year	0	310
Originated two years before current year	1,278	328
Originated three years before current year	91	404
Originated four years before current year	209	741
Originated more than five years before current fiscal year	4,920	4,327
Revolving	2,594	2,844
Revolving to Term	11,619	7,294
Total loans	20,711	16,248
Pass | Commercial | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	1,852,046	1,826,289
Originated one year before current year	1,267,721	1,573,669
Originated two years before current year	1,145,488	985,964
Originated three years before current year	699,429	520,883
Originated four years before current year	450,332	450,911
Originated more than five years before current fiscal year	624,522	495,979
Revolving	2,577,941	2,051,985
Revolving to Term	593,232	651,953
Total loans	9,210,711	8,557,633
Pass | Commercial real estate | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	2,196,306	2,177,841
Originated one year before current year	2,555,236	3,515,702
Originated two years before current year	3,825,305	2,563,638
Originated three years before current year	2,065,037	1,576,044
Originated four years before current year	1,362,703	1,010,351
Originated more than five years before current fiscal year	1,641,611	1,161,119
Revolving	122,708	103,332
Revolving to Term	891,682	960,386
Total loans	14,660,588	13,068,413
Pass | BBCC | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	79,760	81,102
Originated one year before current year	78,420	64,583
Originated two years before current year	55,687	44,307
Originated three years before current year	33,857	38,086
Originated four years before current year	30,215	27,557
Originated more than five years before current fiscal year	22,797	19,028
Revolving	67,668	68,807
Revolving to Term	16,265	33,361
Total loans	384,669	376,831
Special Mention | Commercial | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	46,935	20,038
Originated one year before current year	102,372	90,031
Originated two years before current year	32,250	19,953
Originated three years before current year	40,221	36,906
Originated four years before current year	21,538	25,756
Originated more than five years before current fiscal year	20,535	47,357
Revolving	80,625	89,765
Revolving to Term	28,978	44,348
Total loans	373,454	374,154
Special Mention | Commercial real estate | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	72,020	69,648
Originated one year before current year	31,203	69,946
Originated two years before current year	158,254	68,708
Originated three years before current year	48,524	27,059
Originated four years before current year	37,693	52,107
Originated more than five years before current fiscal year	64,357	95,896
Revolving	0	3,893
Revolving to Term	111,900	64,730
Total loans	523,951	451,987
Special Mention | BBCC | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	1,579	0
Originated one year before current year	1,067	0
Originated two years before current year	807	857
Originated three years before current year	917	700
Originated four years before current year	21	1,001
Originated more than five years before current fiscal year	224	349
Revolving	3,582	2,144
Revolving to Term	3,028	12,728
Total loans	11,225	17,779
Substandard | Commercial | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	27,139	27,271
Originated one year before current year	49,340	41,164
Originated two years before current year	77,835	27,990
Originated three years before current year	35,036	37,618
Originated four years before current year	19,307	10,461
Originated more than five years before current fiscal year	25,503	29,981
Revolving	78,210	72,703
Revolving to Term	40,217	56,716
Total loans	352,587	303,904
Substandard | Commercial real estate | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	47,079	26,638
Originated one year before current year	55,923	56,423
Originated two years before current year	249,269	21,401
Originated three years before current year	102,913	28,983
Originated four years before current year	39,466	61,186
Originated more than five years before current fiscal year	142,110	49,558
Revolving	996	0
Revolving to Term	76,897	48,760
Total loans	714,653	292,949
Substandard | BBCC | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	468	436
Originated one year before current year	976	193
Originated two years before current year	56	252
Originated three years before current year	136	0
Originated four years before current year	598	0
Originated more than five years before current fiscal year	308	604
Revolving	755	15
Revolving to Term	2,876	1,006
Total loans	6,173	2,506
Nonaccrual | Commercial | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	2,221	32
Originated one year before current year	1,072	7,034
Originated two years before current year	4,199	0
Originated three years before current year	1,530	0
Originated four years before current year	604	823
Originated more than five years before current fiscal year	1,357	3,411
Revolving	719	0
Revolving to Term	829	5,461
Total loans	12,531	16,761
Nonaccrual | Commercial real estate | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	3,693	0
Originated one year before current year	411	21,919
Originated two years before current year	3,579	10,706
Originated three years before current year	15,922	1,975
Originated four years before current year	1,930	1,634
Originated more than five years before current fiscal year	3,231	8,632
Revolving	0	0
Revolving to Term	118	1,400
Total loans	28,884	46,266
Nonaccrual | BBCC | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	0	0
Originated one year before current year	114	0
Originated two years before current year	312	482
Originated three years before current year	177	0
Originated four years before current year	63	4
Originated more than five years before current fiscal year	119	1,105
Revolving	0	0
Revolving to Term	551	1,402
Total loans	1,336	2,993
Doubtful | Commercial | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	3,419	0
Originated one year before current year	20,145	7,261
Originated two years before current year	27,016	5,925
Originated three years before current year	1,774	4,875
Originated four years before current year	5,451	1,742
Originated more than five years before current fiscal year	1,494	7,211
Revolving	15,405	0
Revolving to Term	32,272	0
Total loans	106,976	27,014
Doubtful | Commercial real estate | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	7,787	5,360
Originated one year before current year	9,689	429
Originated two years before current year	16,501	30,897
Originated three years before current year	37,455	2,306
Originated four years before current year	22,817	37,777
Originated more than five years before current fiscal year	59,879	35,187
Revolving	0	0
Revolving to Term	50,844	0
Total loans	204,972	111,956
Doubtful | BBCC | Portfolio Segment After Reclassifications
Risk Category Of Loans [Line Items]
Originated in current fiscal year	0	302
Originated one year before current year	397	727
Originated two years before current year	841	254
Originated three years before current year	350	286
Originated four years before current year	15	60
Originated more than five years before current fiscal year	845	84
Revolving	0	0
Revolving to Term	888	0
Total loans	$ 3,336	$ 1,713

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