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Schedule of Impairments on Investments (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | [1]
Investments, Debt and Equity Securities [Abstract] |  |  |  |
Impairment related to intent to sell | $ 0 | $ 0 | $ 0 | $ (26,205)
Total | $ 0 | $ 0 | $ 0 | $ (26,205)
[1] | In response to a rising interest rate environment, the Company took action early in April 2022 to shorten the duration of its fixed maturities portfolio. In connection with these actions, the Company identified fixed maturities securities with a weighted average life of five years or greater as having an intent to sell resulting in other-than-temporary impairment losses. The majority of which were sold in the 2nd quarter of 2022. Most of the proceeds from the sale of these securities were reinvested into fixed income investments with maturities of two years. As a result of these actions, the Company's book yield rose over time. Book yield was approximately 2.2% at December 31, 2021 and 4.0% at September 30, 2023.

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- Definition Other than temporary impairment losses investments related to intent to sell net available-for-sale debt. + References No definition available. + Details
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- Definition Other than temporary impairment losses related to intent to sell. + References No definition available. + Details
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