Financial Instruments with Off-Balance Sheet Risk (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	$ 53,332	$ 46,362
Provision for credit losses	5,181	(393)
Ending balance	58,513	45,969
Commitments to extend credit
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Off-balance sheet liability	11,063,858		$ 9,694,406
Standby letters of credit
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Off-balance sheet liability	564,799		$ 538,047
Commercial
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	47,907	36,040
Provision for credit losses	5,717	5,701
Ending balance	53,624	41,741
Mortgage finance
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	23	6
Provision for credit losses	2	26
Ending balance	25	32
Commercial real estate
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	5,351	10,147
Provision for credit losses	(522)	(6,100)
Ending balance	4,829	4,047
Consumer
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance	51	169
Provision for credit losses	(16)	(20)
Ending balance	$ 35	$ 149

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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