Summary of Significant Accounting Policies - Schedule of Effects of Reclassifications out of Accumulated Other Comprehensive Earnings (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Reclassification Adjustment Out of Accumulated Other Comprehensive Income (Loss)
Net realized gains (losses) - Available-for-sale	$ (2,997)	$ 1,859	$ 3,872
Earnings (losses) before income taxes	720,678	344,321	189,841
Income tax (expense) benefit	(137,267)	(64,967)	(32,750)
Net earnings (losses)	583,411	279,354	157,091
Unrealized Gains and Losses on Available-for-Sale Securities | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment Out of Accumulated Other Comprehensive Income (Loss)
Net realized gains (losses) - Available-for-sale	(2,997)	1,859	3,872
Credit gains (losses) presented within net realized gains	102	(44)	(369)
Earnings (losses) before income taxes	(2,895)	1,815	3,503
Income tax (expense) benefit	608	(381)	(736)
Net earnings (losses)	$ (2,287)	$ 1,434	$ 2,767