Investment Securities (Details Textual) - USD ($)	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Investment Securities Information [Line Items]
Transfer of AFS securities to HTM securities, Fair Value	$ 1,621,990,000	$ 0
Proceeds from sales of investment securities AFS	734,000	51,295,000
Pledged Financial Instruments, Not Separately Reported, Securities	2,200,000,000		$ 2,300,000,000
Interest receivable	83,120,000		80,528,000
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	(65,000)		(55,000)
Federal Home Loan Bank Stock	82,000,000		82,000,000
Federal Reserve Bank Stock	87,000,000		87,000,000
Equity securities with readily determinable fair values, Fair Value	$ 5,000,000		5,000,000
Visa Restricted Stock Owned. Total	78,000
Equity securities	$ 14,000,000		14,000,000
US Treasury Securities
Investment Securities Information [Line Items]
Held to maturity allowance for credit loss	0
US States and Political Subdivisions Debt Securities [Member]
Investment Securities Information [Line Items]
Held to maturity allowance for credit loss	0
Agency mortgage-related securities
Investment Securities Information [Line Items]
Held to maturity allowance for credit loss	0
Held-to-maturity Securities [Member]
Investment Securities Information [Line Items]
Interest receivable	16,000,000		15,000,000
Available-for-sale Securities [Member]
Investment Securities Information [Line Items]
Interest receivable	8,000,000		9,000,000
Federal Home Loan Bank Certificates and Obligations (FHLB) [Member]
Investment Securities Information [Line Items]
Interest receivable	962,000		975,000
Federal Reserve Bank Stock [Member]
Investment Securities Information [Line Items]
Interest receivable	$ 520,000		$ 0

Debt Securities, HTM, Past Due Status

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Investment Securities Information

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Transfer of AFS securities to HTM securities, Fair Value

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Visa Restricted Stock Owned. Total

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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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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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