Investments (Details 2) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Amortized cost
Due in one year or less	$ 4,392
Due after one year through five years	29,466
Due after five years through ten years	16,604
Due after ten years	5,222
Subtotal	55,684
ABS, RMBS and CMBS	1,924
Amortized cost	57,608	$ 56,576
Fair value
Due in one year or less	4,415
Due after one year through five years	30,044
Due after five years through ten years	17,042
Due after ten years	5,856
Subtotal	57,357
ABS, RMBS and CMBS	2,034
Total fixed income securities	$ 59,391	$ 57,839