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v3.23.3

Borrowings - Narrative (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items] |  |
Borrowings | $ 3,650,000,000 | $ 2,125,000,000
Weighted average effective maturity of FHLB advances | 2 years 3 days |
FRB Bank Term Funding Program |  |
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items] |  |
Debt instrument, face amount | $ 750,000,000 |
Debt term | 1 year |
Federal Home Loan Bank of Des Moines |  |
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items] |  |
Federal home loan bank, percent of assets | 45.00% |

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