Investments (Details 3) - Fixed maturity [Member] $ in Millions	Dec. 31, 2015 USD ($)
Amortized Cost Basis, Fiscal Year Maturity [Abstract]
One year or less	$ 922
After one year through five years	5,208
After five years through ten years	11,007
After ten years	4,120
Fixed maturities amortized cost, Subtotal	21,257
ABS (average life of approximately 5 years)	4,961
MBS (average life of approximately 4 years)	5,347
Amortized Cost	31,565
Fair Value, Fiscal Year Maturity [Abstract]
One year or less	935
After one year through five years	5,417
After five years through ten years	11,054
After ten years	4,228
Fixed maturities fair value, Subtotal	21,634
ABS (average life of approximately 5 years)	4,934
MBS (average life of approximately 4 years)	5,716
Fair Value	$ 32,284
Fair Value Percent, Fiscal Year Maturity [Abstract]
One year or less	3.00%
After one year through five years	17.00%
After five years through ten years	34.00%
After ten years	13.00%
Fixed maturities fair value, Subtotal, Percent	67.00%
ABS (average life of approximately 5 years)	15.00%
MBS (average life of approximately 4 years)	18.00%
Fair value, Total, Percent	100.00%