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Investment Securities (Details Textual) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Investment Securities Information [Line Items] |  |
Debt Instrument, Collateral Amount | $ 1,200,000 | $ 1,500,000
Interest Receivable | 168,451 | 167,772
Held to maturity allowance for credit loss | (100) | (100)
Federal Home Loan Bank Stock | 153,600 | 91,500
Federal Reserve Bank Stock | 98,100 | 88,100
Equity securities with readily determinable fair values, Fair Value | 10,900 | 10,700
Equity securities | 15,100 | 12,600
Held-to-maturity Securities [Member] |  |
Investment Securities Information [Line Items] |  |
Interest Receivable | 15,500 | 18,100
Available-for-sale Securities [Member] |  |
Investment Securities Information [Line Items] |  |
Interest Receivable | 23,300 | 21,400
Federal Home Loan Bank Certificates and Obligations (FHLB) [Member] |  |
Investment Securities Information [Line Items] |  |
Interest Receivable | 3,600 | 1,800
Federal Reserve Bank Stock [Member] |  |
Investment Securities Information [Line Items] |  |
Interest Receivable | 1,000 | 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
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] |  |
Investment Securities Information [Line Items] |  |
Held to maturity allowance for credit loss | $ 0 | $ 0

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