Investment Securities (Details Textual) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Investment Securities Information [Line Items]
Debt Instrument, Collateral Amount	$ 1,000,000	$ 1,200,000
Interest Receivable	183,595	161,118
Held to maturity allowance for credit loss	(100)	(100)
Federal Home Loan Bank Stock	188,400	154,400
Federal Reserve Bank Stock	115,900	98,100
Equity securities with readily determinable fair values, Fair Value	15,000	11,100
Equity securities	15,000	15,000
Debt Securities, Available-for-Sale, Allowance for Credit Loss	(1,700)	0
Held-to-maturity Securities [Member]
Investment Securities Information [Line Items]
Interest Receivable	14,600	17,700
Available-for-sale Securities [Member]
Investment Securities Information [Line Items]
Interest Receivable	25,000	23,000
Federal Home Loan Bank Certificates and Obligations (FHLB) [Member]
Investment Securities Information [Line Items]
Interest Receivable	4,100	2,800
Federal Reserve Bank Stock [Member]
Investment Securities Information [Line Items]
Interest Receivable	1,700	0
US Treasury Securities
Investment Securities Information [Line Items]
Held to maturity allowance for credit loss	0	0
US States and Political Subdivisions Debt Securities [Member]
Investment Securities Information [Line Items]
Held to maturity allowance for credit loss	0	0
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Investment Securities Information [Line Items]
Held to maturity allowance for credit loss	$ 0	$ 0

Investment Securities Information

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- Definition

Amount of assets pledged to secure a debt instrument.

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- Definition

Amount 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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Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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

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- Definition

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

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- Definition

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

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