Investments - Available-for-sale Fixed Maturity Securities by Contractual Maturity (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Cost or Amortized Cost
Cost or Amortized Cost	$ 41,102	$ 39,952
Estimated Fair Value
Estimated Fair Value	37,697	44,380
Available-for-sale Fixed Maturities
Cost or Amortized Cost
Due in one year or less	1,012	1,603
Due after one year through five years	9,880	10,637
Due after five years through ten years	13,788	13,294
Due after ten years	16,352	14,411
Cost or Amortized Cost	41,032	39,945
Estimated Fair Value
Due in one year or less	1,001	1,624
Due after one year through five years	9,399	11,229
Due after five years through ten years	12,453	14,338
Due after ten years	14,774	17,182
Estimated Fair Value	$ 37,627	$ 44,373