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Federal Home Loan Bank Advances - Additional Information (Detail) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2020 USD ($) advance | Sep. 30, 2020 | Dec. 31, 2019
Federal Home Loan Bank, Advances [Line Items] |  |  |
Weighted-average rates of FHLB advances | 1.32% |  | 2.19%
Modifications, amount | $ 500.0 |  |
Modifications, number of contracts | advance | 4 |  |
Weighted average interest rate | 1.28% | 2.00% |
Modifications, unamortized prepayment fees | $ 30.0 |  |
FHLB Advances |  |  |
Federal Home Loan Bank, Advances [Line Items] |  |  |
Percentage of borrowings collateralized by investment securities and residential real estate loans | 140.00% |  |

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- Definition Advances From Federal Home Loan Banks, Modifications, Amount + References No definition available. + Details
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- Definition Advances From Federal Home Loan Banks, Modifications, Number Of Contracts + References No definition available. + Details
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- Definition Advances From Federal Home Loan Banks, Modifications, Unamortized Prepayment Fees + References No definition available. + Details
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- Definition Amount of collateral pledged as a percentage of outstanding secured debt. + References No definition available. + Details
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- Definition The calculated weighted average interest rate for Federal Home Loan Bank advances outstanding as of the Balance Sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13(3)(a)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Weighted average interest rate on advances made and reported by Federal Home Loan Bank (FHLBank). + References No definition available. + Details
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