Investments (Details 3) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014
The scheduled maturities of available for sale fixed maturities
Fixed maturities amortized cost, One year or less	$ 888
Fixed maturities fair value, One year or less	906
Fixed maturities fair value, One year or less, Percent	3.00%
Fixed maturities amortized cost, After one year through five years	4,803
Fixed maturities fair value, After one year through five years	5,142
Fixed maturities fair value, After one year through five years, Percent	17.00%
Fixed maturities amortized cost, After five years through ten years	8,797
Fixed maturities fair value, After five years through ten years	9,211
Fixed maturities fair value, After five years through ten years, Percent	30.00%
Fixed maturities amortized cost, After ten years	4,374
Fixed maturities fair value, After ten years	4,695
Fixed maturities fair value, After ten years, Percent	15.00%
Fixed maturities amortized cost, Subtotal	18,862
Fixed maturities fair value, Subtotal	19,954
Fixed maturities fair value, Subtotal, Percent	65.00%
Fixed maturities amortized cost, ABS	3,872
Fixed maturities fair value, ABS	3,887
Fixed maturities fair value, ABS, Percent	13.00%
Fixed maturities amortized cost, MBS	6,340
Fixed maturities fair value, MBS	6,893
Fixed maturities fair value, MBS, Percent	22.00%
Fixed maturity [Member]
The scheduled maturities of available for sale fixed maturities
Amortized Cost	29,074
Fair Value	$ 30,734
Fair value, Total, Percent	100.00%

Asset-backed securities, amortized cost.

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Asset-backed securities, fair value.

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Asset-backed securities, fair value, percent.

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Available-for-sale Securities, Debt Maturities, after Five Through Ten Years, Fair Value, Percent.

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No definition available.

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Available-for-sale Securities, Debt Maturities, after One Through Five Years, Fair Value, Percent.

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Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value, Percent.

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Available for sale securities debt maturities excluding ABS and MBS amortized cost.

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Available for sale securities debt maturities excluding ABS and MBS fair value.

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Available for sale securities debt maturities excluding ABS and MBS fair value percent.

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Available-for-sale Securities, Debt Maturities, Fair Value, Total, Percent.

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Available-for-sale Securities, Debt Maturities, within One Year, Fair Value, Percent.

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Mortgage-backed securities, amortized cost.

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Mortgage-backed securities, fair value, percent.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after adjustments of available-for-sale debt securities at cost, maturing after the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing after the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the next fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale.

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-Glossary Mortgage-Backed Securities

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