Investment Securities - Narrative (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2026 USD ($) security	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($) security	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($) security
Debt and Equity Securities, FV-NI [Line Items]
Accrued interest receivable	$ 58,792,000		$ 58,792,000		$ 58,565,000
Trade date receivables settled after period end	0		0		0
Trade date payables settled after period end	0		0		0
Allowance for credit losses on investments	$ 0		$ 0		$ 0
Number of securities in securities portfolio \| security	344		344		324
Number of securities in securities portfolio, unrealized loss position \| security	240		240		209
Equity securities, at fair value	$ 6,000,000		$ 6,000,000		$ 155,000
Net loss on change in fair value and sale of equity securities	1,000	$ 0	1,000	$ 0
Equity securities without a readily determinable market value (See Note 3)	30,324,000		30,324,000		32,038,000
Equity method investments	16,516,000		16,516,000		17,611,000
Equity method goodwill	17,103,000		17,103,000
Collateral Pledged
Debt and Equity Securities, FV-NI [Line Items]
Securities pledged	829,803,000		829,803,000		810,579,000
Debt Securities
Debt and Equity Securities, FV-NI [Line Items]
Accrued interest receivable	$ 5,100,000		$ 5,100,000		$ 5,101,000

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Equity Securities, FV-NI And Sale Gain (Loss)

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Number of available for sale securities in portfolio.

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Amount excluding accrued interest, of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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