Investments (Investment Income Realized Investment Gains And Losses And Change In Unrealized Investment Gains And Losses) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Investment income:
Interest	$ 417us-gaap_InvestmentIncomeInterest	$ 413us-gaap_InvestmentIncomeInterest	$ 420us-gaap_InvestmentIncomeInterest
Dividends	138us-gaap_InvestmentIncomeDividend	122us-gaap_InvestmentIncomeDividend	115us-gaap_InvestmentIncomeDividend
Other	2	3	3
Total	557us-gaap_GrossInvestmentIncomeOperating	538us-gaap_GrossInvestmentIncomeOperating	538us-gaap_GrossInvestmentIncomeOperating
Less investment expenses	8	9	7
Total	549us-gaap_NetInvestmentIncome	529us-gaap_NetInvestmentIncome	531us-gaap_NetInvestmentIncome
Realized investment gains and losses summary:
Other	3	6	2
Total	133us-gaap_RealizedInvestmentGainsLosses	83us-gaap_RealizedInvestmentGainsLosses	42us-gaap_RealizedInvestmentGainsLosses
Change in unrealized investment gains and losses:
Unrealized gains on investments available-for-sale	250	299	251
OCI, portion attributable to Parent	130	202	124
OCI, portion attributable to Parent	370	577	352
Fixed Maturities
Realized investment gains and losses summary:
Gross realized gains	21	15	36
Gross realized losses	(3)	0	0
Other-than-temporary impairments	(15)	(2)	(1)
Change in unrealized investment gains and losses:
Unrealized gains on investments available-for-sale	106	(387)	176
Equity Securities
Realized investment gains and losses summary:
Gross realized gains	136	64	39
Gross realized losses	0	0	(2)
Other-than-temporary impairments	(9)	0	(32)
Change in unrealized investment gains and losses:
Unrealized gains on investments available-for-sale	278	847	210
Accumulated Net Unrealized Investment Gain (Loss)
Change in unrealized investment gains and losses:
OCI, portion attributable to Parent	134	161	135
OCI, portion attributable to Parent	$ 250	$ 299	$ 251

Income derived from those other than interest and dividends.

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This item represents realized investment gains (losses) included in earnings for the period excluding those relating to other than temporary impairment losses on investments in debt securities. Includes realized investment gains and losses generated from the sale of debt securities, equity securities, investments in joint ventures and limited partnerships and from other than temporary impairments on investments other than debt securities. Also includes realized investment gains and losses are generated from prepayment premiums, recoveries of principal on previously impaired securities, provisions for losses on commercial mortgage and other loans, and fair value changes on embedded derivatives and derivatives that do not qualify for hedge accounting treatment, except those derivatives used in the Company's capacity as a broker or dealer.

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Other Than Temporary Impairment Losses

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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Amount, before 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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Amount of dividend income on nonoperating securities.

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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Amount of expenses related to the generation of investment income.

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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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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

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