Business combination recognized identifiable assets acquired and liabilities assumed loans carrying value.

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- Definition

Business combination recognized identifiable assets acquired and liabilities assumed loans fair value.

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- Definition

Financing receivable from securitization.

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Loans and leases receivable unaccreted discounts and deferred fees net of deferred costs.

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- Definition

Proceeds on sale of factored receivables and loans.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of interest income on financing receivable on nonaccrual status.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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Loans and Allowance for Credit Losses - Additional Information (Details) - USD ($)		9 Months Ended		12 Months Ended
	Jun. 25, 2026	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025	Jul. 15, 2026	Jun. 30, 2026	Feb. 01, 2026	Jun. 30, 2025	Jun. 03, 2025	Apr. 01, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans unaccreted discounts and deferred fees net of deferred costs		$ 28,400,000		$ 22,000,000
Allowance for credit losses		(54,418,000)	$ (42,563,000)	(43,949,000)		$ (53,591,000)		$ (40,035,000)			$ (40,304,000)
Interest income realized on nonaccrual loans that became accrual loans during the reporting period		129,000,000	$ 135,000,000
Restructured loans subsequent payment default		0		$ 0
Proceeds on sale of factored receivables and loans	$ 27,500,000
Gain loss on disposition of assets	$ 3,500,000
Securitized loan transactions		87,500,000			$ 87,500,000			$ 250,000,000	$ 150,000,000	$ 100,000,000
Fair value of loans acquired							$ 805,200,000
April Mortgage Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Securitized loan transactions										$ 100,000,000
June Mortgage Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Securitized loan transactions									$ 150,000,000
July Mortgage Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Securitized loan transactions					$ 87,500,000
Keystone Bancshares, Inc.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fair value of loans acquired							805,200,000
Contractual balance							812,800,000
PSL Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Contractual balance							804,600,000
PCD Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans unaccreted discounts and deferred fees net of deferred costs		674,000
Allowance for credit losses		$ (61,300)
Contractual balance							$ 8,200,000