Investments - Scheduled maturities for fixed income securities (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Amortized cost, net
Due in one year or less	$ 1,454	$ 1,105
Due after one year through five years	22,599	21,039
Due after five years through ten years	12,412	13,808
Due after ten years	3,379	4,281
Subtotal	39,844	40,233
ABS	2,183	1,143
Amortized cost, net	42,027	41,376
Fair value
Due in one year or less	1,455	1,111
Due after one year through five years	22,035	21,291
Due after five years through ten years	11,796	14,079
Due after ten years	3,286	4,500
Subtotal	38,572	40,981
ABS	2,173	1,155
Total	$ 40,745	$ 42,136