Allowance for Credit Losses - Roll Forward Of the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Allowance for credit losses:
Beginning balance	$ 293,955	$ 201,756	$ 201,756
Charge-offs	(3,260)	(1,129)
Recoveries	943	1,254
Net charge-offs	(2,317)	125
Provision for (recovery of) credit losses on loans	4,224	2,050
Ending balance	295,862	203,931	293,955
Nonaccruing loans with no allowance for credit losses	68,416	21,561
Commercial and industrial
Allowance for credit losses:
Beginning balance	57,831	41,864	41,864
Charge-offs	(1,070)	(94)
Recoveries	150	967
Net charge-offs	(920)	873
Provision for (recovery of) credit losses on loans	8,903	(853)
Ending balance	65,814	41,884	57,831
Nonaccruing loans with no allowance for credit losses	23,394	5,134
Construction and land development
Allowance for credit losses:
Beginning balance	31,359	19,200	19,200
Charge-offs	(1)	0
Recoveries	0	0
Net charge-offs	(1)	0
Provision for (recovery of) credit losses on loans	5,611	1,645
Ending balance	36,969	20,845	31,359
Nonaccruing loans with no allowance for credit losses	5,146	711
Real estate – 1-4 family mortgage:
Allowance for credit losses:
Beginning balance	61,249	45,498	45,498
Charge-offs	(525)	(309)
Recoveries	26	33
Net charge-offs	(499)	(276)
Provision for (recovery of) credit losses on loans	5,903	2,879
Ending balance	66,653	48,101	61,249
Nonaccruing loans with no allowance for credit losses	2,473	5,384
Commercial real estate - owner occupied
Allowance for credit losses:
Beginning balance	38,961	16,993	16,993
Charge-offs	(1,136)	(461)
Recoveries	676	4
Net charge-offs	(460)	(457)
Provision for (recovery of) credit losses on loans	(1,060)	1,290
Ending balance	37,441	17,826	38,961
Nonaccruing loans with no allowance for credit losses	8,805	6,418
Commercial real estate - non owner occupied
Allowance for credit losses:
Beginning balance	99,605	71,664	71,664
Charge-offs	(198)	0
Recoveries	63	2
Net charge-offs	(135)	2
Provision for (recovery of) credit losses on loans	(15,090)	(2,885)
Ending balance	84,380	68,781	99,605
Nonaccruing loans with no allowance for credit losses	28,598	3,914
Consumer
Allowance for credit losses:
Beginning balance	4,950	6,537	6,537
Charge-offs	(330)	(265)
Recoveries	28	248
Net charge-offs	(302)	(17)
Provision for (recovery of) credit losses on loans	(43)	(26)
Ending balance	4,605	6,494	$ 4,950
Nonaccruing loans with no allowance for credit losses	$ 0	$ 0

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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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.

+ References

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

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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.

+ References

No definition available.

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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.

+ References

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
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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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.

+ References

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

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- Definition

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

+ References

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
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-16

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