Financial Instruments with Off-Balance Sheet Risk (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	$ 62,255	$ 53,332
Provision for credit losses	(1,242)	533
Ending balance	61,013	53,865
Commitments to extend credit
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Off-balance sheet liability	11,783,332		$ 12,193,441
Standby letters of credit
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Off-balance sheet liability	637,349		$ 610,178
Commercial
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	58,209	47,907
Provision for credit losses	(277)	604
Ending balance	57,932	48,511
Mortgage finance
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	16	23
Provision for credit losses	(8)	(2)
Ending balance	8	21
Commercial real estate
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	3,979	5,351
Provision for credit losses	(964)	(61)
Ending balance	3,015	5,290
Consumer
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	51	51
Provision for credit losses	7	(8)
Ending balance	$ 58	$ 43

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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