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Investment Securities (Details Textual) - USD ($) | 3 Months Ended |
--- | --- | ---
Sep. 30, 2024 | Dec. 31, 2023
Investment Securities Information [Line Items] |  |
Debt Instrument, Collateral Amount | $ 1,400,000,000 | $ 1,600,000,000
Interest Receivable | 167,777,000 | 169,569,000
Held to maturity allowance for credit loss | (75,000) | (75,000)
Federal Home Loan Bank Stock | 90,000,000 | 143,000,000
Federal Reserve Bank Stock | 88,000,000 | 87,000,000
Equity securities with readily determinable fair values, Fair Value | 11,000,000 | 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 | 17,000,000 | 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 | 855,000 | 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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- Definition Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (aaa) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-5 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 + Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483467/210-10-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482736/825-10-45-1A + Details
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