Investments - Schedule of Contractual Maturities of Investments (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Amortized cost
Due in one year or less	$ 690
Due after one year through five years	3,861
Due after five years through ten years	3,573
Due after ten years	4,688
Total	12,812	$ 12,230
Fair value
Due in one year or less	687
Due after one year through five years	3,717
Due after five years through ten years	3,334
Due after ten years	3,996
Total	$ 11,734	$ 13,022
% of fair value
Due in one year or less	5.90%
Due after one year through five years	31.70%
Due after five years through ten years	28.40%
Due after ten years	34.00%
Total	100.00%