Financial Instruments with Off-Balance Sheet Risk (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	$ 62,255	$ 53,332
Provision for credit losses	3,245	5,181
Ending balance	65,500	58,513
Commitments to extend credit
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Off-balance sheet liability	11,732,168		$ 12,193,441
Standby letters of credit
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Off-balance sheet liability	819,492		$ 610,178
Commercial
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	58,209	47,907
Provision for credit losses	4,871	5,717
Ending balance	63,080	53,624
Mortgage finance
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	16	23
Provision for credit losses	18	2
Ending balance	34	25
Commercial real estate
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	3,979	5,351
Provision for credit losses	(1,645)	(522)
Ending balance	2,334	4,829
Consumer
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	51	51
Provision for credit losses	1	(16)
Ending balance	$ 52	$ 35

Allowance For Off-Balance Sheet Credit Losses [Roll Forward]

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- Definition

Financing Receivable Allowance For Credit Losses Off Balance Sheet Liability

+ References

No definition available.

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- Definition

Financing Receivable, Provision For Off-Balance Sheet Credit Losses

+ References

No definition available.

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- Definition

The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-11

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-10

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