Financial Instruments with Off-Balance Sheet Risk (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	$ 62,255	$ 53,332
Provision for credit losses	2,848	3,299
Ending balance	65,103	56,631
Commitments to extend credit
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Off-balance sheet liability	11,888,078		$ 12,193,441
Standby letters of credit
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Off-balance sheet liability	745,856		$ 610,178
Commercial
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	58,209	47,907
Provision for credit losses	3,879	4,075
Ending balance	62,088	51,982
Mortgage finance
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	16	23
Provision for credit losses	11	7
Ending balance	27	30
Commercial real estate
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	3,979	5,351
Provision for credit losses	(1,053)	(767)
Ending balance	2,926	4,584
Consumer
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	51	51
Provision for credit losses	11	(16)
Ending balance	$ 62	$ 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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