Investments - Schedule of Maturities for Fixed Income Securities (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Amortized cost, net
Due in one year or less	$ 2,692	$ 3,422
Due after one year through five years	23,799	23,218
Due after five years through ten years	16,675	12,553
Due after ten years	8,961	8,717
Subtotal	52,127	47,910
ABS	1,661	1,739
Amortized cost, net	53,788	49,649
Fair value
Due in one year or less	2,655	3,374
Due after one year through five years	23,172	22,614
Due after five years through ten years	16,305	12,273
Due after ten years	8,773	8,859
Subtotal	50,905	47,120
ABS	1,671	1,745
Total	$ 52,576	$ 48,865