Investments - Scheduled maturities for fixed Income securities (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Amortized cost, net
Due in one year or less	$ 3,092
Due after one year through five years	24,271
Due after five years through ten years	22,000
Due after ten years	10,757
Subtotal	60,120
ABS and MBS	1,331
Amortized cost, net	61,451	$ 56,293
Fair value
Due in one year or less	3,136
Due after one year through five years	25,587
Due after five years through ten years	24,018
Due after ten years	12,265
Subtotal	65,006
ABS and MBS	1,348
Fair value	$ 66,354	$ 59,044