Description of Business, Basis of Presentation, and Summary of Significant Accounting Policies - Schedule of Transition Impact on the Liability for Future Policy Benefits (Details) - USD ($) $ in Thousands		12 Months Ended
	Jan. 01, 2021	Dec. 31, 2023	Dec. 31, 2022
Present Value of Expected Net Premiums
Balance at then current discount rate, beginning of period, Present value of expected net premiums	$ 10,867,358	$ 13,053,386	$ 14,988,852
Net premiums collected, Present value of expected net premiums	(137,112)	(1,682,924)	(1,623,000)
Balance at original discount rate, beginning of period, Present value of expected net premium	10,730,246	13,521,221	12,800,441
Effect of changes in discount rate assumptions, Present value of expected net premiums	2,774,082	(35,200)	(467,835)
Balance at then current discount rate, end of period, Present value of expected net premiums	13,504,328	13,977,353	13,053,386
Present Value of Expected Future Policy Benefits
Balance at original discount rate, beginning of period, Present value of expected future policy benefits	17,445,700	19,706,818	18,991,175
Effect of changes in discount rate assumptions, Present value of expected future policy benefits	5,624,494	116,741	(563,565)
Expected future policy benefits at original discount rate, end of period, Present value of expected future policy benefits	$ 23,070,194	$ 20,391,694	$ 19,706,818