Represents the total of interest and dividend income, including any amortization and accretion (as applicable) of discounts and premiums, earned from (1) loans and leases whether held-for-sale or held-in-portfolio; (2) investment securities; (3) federal funds sold; (4) securities purchased under agreements to resell; (5) investments in banker's acceptances, commercial paper, or certificates of deposit; (6) dividend income; or (7) other investments not otherwise specified herein.

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-Name Accounting Standards Codification

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Amount of expenses related to the generation of investment income.

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-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Section 16

-Article 12

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Investments and Cash - Net Investment Income (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net Investment Income
Gross investment income									$ 412	$ 401	$ 413
Investment expenses									(9)	(8)	(9)
Net investment income	102us-gaap_NetInvestmentIncome	102us-gaap_NetInvestmentIncome	96us-gaap_NetInvestmentIncome	103us-gaap_NetInvestmentIncome	107us-gaap_NetInvestmentIncome	99us-gaap_NetInvestmentIncome	93us-gaap_NetInvestmentIncome	94us-gaap_NetInvestmentIncome	403us-gaap_NetInvestmentIncome	393us-gaap_NetInvestmentIncome	404us-gaap_NetInvestmentIncome
Fixed Maturities, Managed Externally [Member]
Net Investment Income
Gross investment income									324	322	346
Fixed Maturities, Managed Internally [Member]
Net Investment Income
Gross investment income									74	74	60
Other Invested Assets, Internally Managed [Member]
Net Investment Income
Gross investment income									13	5	6
Other Investments [Member]
Net Investment Income
Gross investment income									$ 1	$ 0	$ 1