Investment Securities (Details Textual) - USD ($)	3 Months Ended
Mar. 31, 2024	Dec. 31, 2023
Investment Securities Information [Line Items]
Debt Instrument, Collateral Amount	$ 1,500,000,000	$ 1,600,000,000
Interest receivable	167,092,000	169,569,000
Held to maturity allowance for credit loss	(76,000)	(75,000)
Federal Home Loan Bank Stock	86,000,000	143,000,000
Federal Reserve Bank Stock	88,000,000	87,000,000
Equity securities with readily determinable fair values, Fair Value	7,000,000	7,000,000
Equity securities	13,000,000	35,000,000
Held-to-maturity Securities [Member]
Investment Securities Information [Line Items]
Interest receivable	16,000,000	18,000,000
Available-for-sale Securities [Member]
Investment Securities Information [Line Items]
Interest receivable	16,000,000	15,000,000
Equity Securities [Member]
Investment Securities Information [Line Items]
Gain (Loss) on Sale of Investments	4,000,000
Federal Home Loan Bank Certificates and Obligations (FHLB) [Member]
Investment Securities Information [Line Items]
Interest receivable	2,000,000	4,000,000
Federal Reserve Bank Stock [Member]
Investment Securities Information [Line Items]
Interest receivable	921,000	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
Agency mortgage-related securities
Investment Securities Information [Line Items]
Held to maturity allowance for credit loss	$ 0	$ 0

Investment Securities Information

No definition available.

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- Definition

Amount of assets pledged to secure a debt instrument.

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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

The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities.

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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.

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