Investments - Scheduled maturities for fixed income securities (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Amortized cost, net
Due in one year or less	$ 1,279
Due after one year through five years	18,216
Due after five years through ten years	13,464
Due after ten years	5,492
Subtotal	38,451
ABS and MBS	986
Amortized cost, net	39,437	$ 40,034
Fair value
Due in one year or less	1,291
Due after one year through five years	18,810
Due after five years through ten years	13,818
Due after ten years	5,679
Subtotal	39,598
ABS and MBS	996
Total	$ 40,594	$ 42,565