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Assets Purchased under Resale Agreements and Sold under Repurchase Agreements - Resale Agreements (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022
Offsetting Assets [Line Items] |  |  |  |  |
Gross resale agreements | $ 785,000,000 |  | $ 785,000,000 |  | $ 760,000,000
Average yield | 2.73% | 2.41% | 2.55% | 1.96% |
Loans purchased under agreements to resell | $ 0 |  | $ 0 |  | $ 32,200,000
Loans Purchased Under Resale Agreements |  |  |  |  |
Offsetting Assets [Line Items] |  |  |  |  |
Weighted-average yields |  | 3.87% | 7.27% | 2.10% |

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- Definition Average yield on securities purchased under agreements to resell. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-K (SK) -Number 229 -Section 1402 -Paragraph (a) -Publisher SEC Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-K (SK) -Number 229 -Section 1402 -Paragraph (b) -Subparagraph (2) -Publisher SEC + Details
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- Definition Amount, before effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483466/210-20-50-3 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483444/210-20-55-7 + Details
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