Investments - Scheduled maturities for fixed Income securities (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Amortized cost
Due in one year or less	$ 3,214
Due after one year through five years	24,108
Due after five years through ten years	18,194
Due after ten years	9,593
Subtotal	55,109
ABS and MBS	1,184
Amortized cost	56,293	$ 57,134
Fair value
Due in one year or less	3,239
Due after one year through five years	24,781
Due after five years through ten years	19,177
Due after ten years	10,566
Subtotal	57,763
ABS and MBS	1,281
Fair value	$ 59,044	$ 57,170