Investments (Details 2) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Amortized cost
Due in one year or less	$ 4,030
Due after one year through five years	26,999
Due after five years through ten years	16,885
Due after ten years	5,633
Subtotal	53,547
ABS, RMBS and CMBS	3,654
Amortized cost	57,201	$ 59,672
Fair value
Due in one year or less	4,050
Due after one year through five years	27,337
Due after five years through ten years	16,778
Due after ten years	6,043
Subtotal	54,208
ABS, RMBS and CMBS	3,740
Fair value	$ 57,948	$ 62,440