Future Policy Benefits - Schedule of Balances and Changes in Present Value of Expected Net Premiums and Present Value of Expected Future Policy Benefits Underlying LFPB (Details) - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
	Jan. 01, 2021	Mar. 31, 2023	Dec. 31, 2022
Present Value of Expected Net Premiums
Balance at current discount rate, beginning of period, Present value of expected net premiums	$ 10,867,358	$ 13,053,386	$ 14,988,852
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 cash flow assumptions, Present value of expected net premiums			26,090
Effect of actual variances from expected experience, Present value of expected net premiums		(66,059)	8,653
Adjusted balance, beginning of period		13,455,162	12,835,184
Issuances, Present value of expected net premiums		465,861	1,892,716
Interest accrual at Original discount rate, Present value of expected net premiums		130,130	486,436
Net premiums collected, Present value of expected net premiums	(137,112)	(414,681)	(1,623,000)
Foreign currency translation, Present value of expected net premiums		1,326	(70,115)
Expected net premiums at original discount rate, end of period		13,637,798	13,521,221
Effect of changes in discount rate assumptions, Present value of expected net premiums	2,774,082	(117,304)	(467,835)
Balance at current discount rate, end of period, Present value of expected net premiums	13,504,328	13,520,494	13,053,386
Present Value of Expected Future Policy Benefits
Balance at current discount rate, beginning of period, Present value of expected future policy benefits		19,143,253	23,309,576
Balance at original discount rate, beginning of period	23,070,194	19,855,932	19,706,818
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 cash flow assumptions, Present value of expected future policy benefits		0	29,915
Effect of actual variances from expected experience, Present value of expected future policy benefits		(58,593)	21,101
Adjusted balance, beginning of period, Present value of expected future policy benefits		19,648,225	19,042,191
Issuances, Present value of expected future policy benefits		465,885	1,892,730
Interest accrual at Original discount rate, Present value of expected future policy benefits		206,814	796,017
Benefit payments, Present value of expected future policy benefits		(467,008)	(1,915,518)
Foreign currency translation, Present value of expected future policy benefits		2,016	(108,602)
Expected future policy benefits at original discount rate, end of period, Present value of expected future policy benefits	23,070,194	19,855,932	19,706,818
Effect of changes in discount rate assumptions, Present value of expected future policy benefits	$ 5,624,494	13,498	(563,565)
Expected future policy benefits at current discount rate, end of period, Present value of expected future policy benefits		19,869,430	19,143,253
LFPB		6,561,624	6,297,906
Less: reinsurance recoverables		3,154,789	3,153,121
Net LFPB, after reinsurance recoverables		$ 3,194,147	$ 2,936,746
Weighted-average duration of net LFPB		7 years 9 months 18 days	7 years 9 months 18 days
Term Life
Present Value of Expected Future Policy Benefits
LFPB		$ 6,348,936	$ 6,089,867