Investment Securities (Details Textual) - USD ($)	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Investment Securities Information [Line Items]
Proceeds from sales of AFS investment securities	$ 0	$ 734,000
Debt Instrument, Collateral Amount	2,200,000,000		$ 2,300,000,000
Interest receivable	152,404,000		144,449,000
Debt Securities, Held-to-maturity, Nonaccrual, Interest Income	0	$ 0
Debt Securities, Held to Maturity, Past Due	0		0
Held to maturity allowance for credit loss	(25,000)		(54,000)
Federal Home Loan Bank Stock	245,000,000		209,000,000
Federal Reserve Bank Stock	87,000,000		87,000,000
Equity securities with readily determinable fair values, Fair Value	6,000,000		6,000,000
Equity Securities without Readily Determinable Fair Value, Amount	24,228,000		19,225,000
Held-to-maturity Securities [Member]
Investment Securities Information [Line Items]
Interest receivable	16,000,000		19,000,000
Available-for-sale Securities [Member]
Investment Securities Information [Line Items]
Interest receivable	12,000,000		9,000,000
Federal Home Loan Bank Certificates and Obligations (FHLB) [Member]
Investment Securities Information [Line Items]
Interest receivable	4,000,000		3,000,000
Federal Reserve Bank Stock [Member]
Investment Securities Information [Line Items]
Interest receivable	776,000		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

Debt Securities, HTM, Past Due Status

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- Definition

Investment Securities Information

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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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Amount of interest income on investment in debt security measured at amortized cost (held-to-maturity), on nonaccrual status.

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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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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.

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The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period.

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