Investments - Schedule of Equity Securities and Trading Debt Securities Net Unrealized Investment Gains and Losses (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Net Realized Or Unrealized Gain Loss On Trading Securities [Abstract]
Net unrealized investment gains (losses)	$ (92,793)	$ 14,154	$ 49,719

Amount of net unrealized gain (loss) on investments in equity securities and trading debt securities.

No definition available.

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