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v3.20.2

Amounts Recorded for Margin Borrowing Facilities and Subordinated Notes (Parenthetical) (Detail) |  |  | 1 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Apr. 25, 2018 | Mar. 23, 2017 | Aug. 31, 2020 | Sep. 30, 2020 | Dec. 31, 2019
7.875% Subordinated Notes due 2047 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Subordinated Notes percentage |  |  |  | 7.875% | 7.875%
Subordinated Notes due date | 2047 | 2047 |  | 2047 | 2047
7.75% Subordinated Notes due 2045 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Subordinated Notes percentage |  |  | 7.75% | 7.75% | 7.75%
Subordinated Notes due date | 2045 |  | 2045 | 2045 | 2045

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + 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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- Details
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