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Schedule of Impairments on Investments (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	[1]
Investments, Debt and Equity Securities [Abstract]
Impairment related to intent to sell	$ 0	$ 0	$ (26,205)
Total	$ 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 second quarter of 2022. Since April 2022, the Company has been investing in securities with much shorter durations. 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 4.4% at December 31, 2024.

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