Allowance for Credit Losses - Roll Forward Of the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Allowance for credit losses:
Beginning balance	$ 295,862	$ 203,931	$ 293,955	$ 201,756	$ 201,756
Charge-offs	(3,347)	(12,979)	(6,607)	(14,108)
Recoveries	577	925	1,520	2,179
Net (charge-offs) recoveries	(2,770)	(12,054)	(5,087)	(11,929)
Provision for (recovery of) credit losses on loans	1,166	75,400	5,390	77,450
Ending balance	296,008	290,770	296,008	290,770	293,955
Nonaccruing loans with no allowance for credit losses	61,711	21,868	61,711	21,868
Cumulative Effect, Period Of Adoption, Adjustment
Allowance for credit losses:
Beginning balance	1,750	23,493	1,750	23,493	23,493
Ending balance					1,750
Commercial and industrial
Allowance for credit losses:
Beginning balance	65,814	41,884	57,831	41,864	41,864
Charge-offs	(2,223)	(8,217)	(3,293)	(8,310)
Recoveries	382	631	532	1,597
Net (charge-offs) recoveries	(1,841)	(7,586)	(2,761)	(6,713)
Provision for (recovery of) credit losses on loans	1,634	19,972	10,537	19,119
Ending balance	67,357	61,410	67,357	61,410	57,831
Nonaccruing loans with no allowance for credit losses	22,859	899	22,859	899
Commercial and industrial \| Cumulative Effect, Period Of Adoption, Adjustment
Allowance for credit losses:
Beginning balance	1,750	7,140	1,750	7,140	7,140
Ending balance					1,750
Construction and land development
Allowance for credit losses:
Beginning balance	36,969	20,845	31,359	19,200	19,200
Charge-offs	0	(105)	(1)	(106)
Recoveries	2	0	2	1
Net (charge-offs) recoveries	2	(105)	1	(105)
Provision for (recovery of) credit losses on loans	2,914	7,369	8,525	9,014
Ending balance	39,885	30,294	39,885	30,294	31,359
Nonaccruing loans with no allowance for credit losses	4,032	2,331	4,032	2,331
Construction and land development \| Cumulative Effect, Period Of Adoption, Adjustment
Allowance for credit losses:
Beginning balance	0	2,185	0	2,185	2,185
Ending balance					0
Real estate – 1-4 family mortgage:
Allowance for credit losses:
Beginning balance	66,653	48,101	61,249	45,498	45,498
Charge-offs	(402)	(319)	(927)	(628)
Recoveries	133	37	159	70
Net (charge-offs) recoveries	(269)	(282)	(768)	(558)
Provision for (recovery of) credit losses on loans	453	13,150	6,356	16,029
Ending balance	66,837	61,172	66,837	61,172	61,249
Nonaccruing loans with no allowance for credit losses	2,312	4,275	2,312	4,275
Real estate – 1-4 family mortgage: \| Cumulative Effect, Period Of Adoption, Adjustment
Allowance for credit losses:
Beginning balance	0	203	0	203	203
Ending balance					0
Commercial real estate - owner occupied
Allowance for credit losses:
Beginning balance	37,441	17,826	38,961	16,993	16,993
Charge-offs	(227)	0	(1,363)	0
Recoveries	7	56	683	58
Net (charge-offs) recoveries	(220)	56	(680)	58
Provision for (recovery of) credit losses on loans	(1,274)	9,186	(2,334)	10,017
Ending balance	35,947	31,127	35,947	31,127	38,961
Nonaccruing loans with no allowance for credit losses	4,446	4,700	4,446	4,700
Commercial real estate - owner occupied \| Cumulative Effect, Period Of Adoption, Adjustment
Allowance for credit losses:
Beginning balance	0	4,059	0	4,059	4,059
Ending balance					0
Commercial real estate - non owner occupied
Allowance for credit losses:
Beginning balance	84,380	68,781	99,605	71,664	71,664
Charge-offs	(176)	(3,944)	(374)	(4,405)
Recoveries	18	60	81	64
Net (charge-offs) recoveries	(158)	(3,884)	(293)	(4,341)
Provision for (recovery of) credit losses on loans	(2,463)	25,866	(17,553)	23,440
Ending balance	81,759	100,667	81,759	100,667	99,605
Nonaccruing loans with no allowance for credit losses	28,062	9,663	28,062	9,663
Commercial real estate - non owner occupied \| Cumulative Effect, Period Of Adoption, Adjustment
Allowance for credit losses:
Beginning balance	0	9,904	0	9,904	9,904
Ending balance					0
Consumer
Allowance for credit losses:
Beginning balance	4,605	6,494	4,950	6,537	6,537
Charge-offs	(319)	(394)	(649)	(659)
Recoveries	35	141	63	389
Net (charge-offs) recoveries	(284)	(253)	(586)	(270)
Provision for (recovery of) credit losses on loans	(98)	(143)	(141)	(169)
Ending balance	4,223	6,100	4,223	6,100	4,950
Nonaccruing loans with no allowance for credit losses	0	0	0	0
Consumer \| Cumulative Effect, Period Of Adoption, Adjustment
Allowance for credit losses:
Beginning balance	$ 0	$ 2	$ 0	$ 2	2
Ending balance					$ 0

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
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Amount, excluding accrued interest, of decrease (increase) in allowance for credit loss on financing receivable from writeoff (recovery). Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
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-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amortized cost excluding accrued interest, of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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