Investments (Details 2) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Amortized cost
Due in one year or less	$ 4,044
Due after one year through five years	25,110
Due after five years through ten years	16,379
Due after ten years	8,048
Subtotal	53,581
ABS, RMBS and CMBS	4,654
Amortized cost	58,235	59,672
Fair value
Due in one year or less	4,092
Due after one year through five years	25,883
Due after five years through ten years	17,180
Due after ten years	9,439
Subtotal	56,594
ABS, RMBS and CMBS	4,809
Total fixed income securities	$ 61,403	$ 62,440