Investment Securities - Narrative (Details)	Mar. 31, 2024 USD ($) security	Dec. 31, 2023 USD ($) security
Debt and Equity Securities, FV-NI [Line Items]
Accrued interest receivable	$ 53,506,000	$ 52,715,000
Allowance for credit losses for investments	$ 0	$ 0
Number of securities in securities portfolio \| security	340	439
Number of securities in securities portfolio, unrealized loss position \| security	316	370
Equity securities without readily determinable market value	$ 25,589,000	$ 25,191,000
Federal home loan bank stock	33,948,000	34,190,000
Collateral Pledged
Debt and Equity Securities, FV-NI [Line Items]
Securities pledged	949,958,000	929,546,000
Debt Securities
Debt and Equity Securities, FV-NI [Line Items]
Accrued interest receivable	$ 5,409,000	$ 7,212,000

Number of available for sale securities in portfolio.

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- Definition

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).

+ References

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Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

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Amount of investment in equity security without readily determinable fair value.

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

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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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