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Allowance for Credit Losses - Schedule of Changes in the Allowance for Loan and Lease Losses (Details) - USD ($) $ in Thousands		12 Months Ended
	Sep. 01, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Changes in allowance for loan losses
Beginning balance		$ 125,083	$ 117,522
Charge-offs		(42,251)	(26,810)
Recoveries		4,652	2,282
Merger Day 1 allowance on non-PCD loans		67,229
Financing Receivable, Excluding Accrued Interest, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date	$ 64,510	64,511
Provision (credit) for loan and lease losses excluding unfunded commitments		33,615	32,089	$ 38,703
Ending balance		252,839	125,083	117,522
Commercial real estate loans
Changes in allowance for loan losses
Beginning balance		74,171	81,410
Charge-offs		(11,018)	(4,425)
Recoveries		252	0
Merger Day 1 allowance on non-PCD loans		31,820
Financing Receivable, Excluding Accrued Interest, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date		38,744
Provision (credit) for loan and lease losses excluding unfunded commitments		8,422	(2,814)	14,328
Ending balance		142,391	74,171	81,410
Commercial
Changes in allowance for loan losses
Beginning balance		44,169	29,557
Charge-offs		(31,034)	(22,345)
Recoveries		3,657	2,241
Merger Day 1 allowance on non-PCD loans		17,891
Financing Receivable, Excluding Accrued Interest, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date		24,294
Provision (credit) for loan and lease losses excluding unfunded commitments		27,513	34,716	21,537
Ending balance		86,490	44,169	29,557
Consumer loans
Changes in allowance for loan losses
Beginning balance		6,743	6,555
Charge-offs		(199)	(40)
Recoveries		743	41
Merger Day 1 allowance on non-PCD loans		17,518
Financing Receivable, Excluding Accrued Interest, Purchased with Credit Deterioration, Allowance for Credit Loss at Acquisition Date		1,473
Provision (credit) for loan and lease losses excluding unfunded commitments		(2,320)	187	2,838
Ending balance		$ 23,958	$ 6,743	$ 6,555

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- Definition

Financing Receivable, Excluding Accrued Interest, Merger Day One allowance on Non PCD Loans

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- Definition

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

+ References

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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- Definition

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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- Definition

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
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-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 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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Amount, excluding accrued interest, of allowance for credit loss at acquisition date of financing receivable purchased with credit deterioration. 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 (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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-URI https://asc.fasb.org/1943274/2147479319/326-20-50-19

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