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Current Fair Value of Debt (Parenthetical) (Detail) - 7.875% Subordinated Notes due 2047 - USD ($) $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Apr. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Subordinated Notes percentage | 7.875% | 7.875% | 7.875%
Subordinated Notes due date | 2047 | 2047 | 2047
Unamortized Debt Issuance Costs |  |  | $ 3.6
Unamortized debt issuance cost, written off | $ 3.5 |  |

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1B -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611 Reference 2: 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 https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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