Consolidated Balance Sheets Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Available-for-sale Debt Securities, Amortized Cost Basis	$ 55,362,000,000	$ 60,641,000,000
Variable Interest Entity, Consolidated, Carrying Amount, Assets	246,000,000	199,000,000
Trading Securities, Equity, Cost	10,000,000us-gaap_TradingSecuritiesEquityCost	14,504,000,000us-gaap_TradingSecuritiesEquityCost
Available-for-sale Equity Securities, Amortized Cost Basis	1,027,000,000	850,000,000
Available-for-sale Securities, Equity Securities	1,047,000,000	868,000,000
Trading Securities, Equity	11,000,000us-gaap_TradingSecuritiesEquity	19,745,000,000us-gaap_TradingSecuritiesEquity
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities	6,000,000	33,000,000
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	1,500,000,000us-gaap_CommonStockSharesAuthorized	1,500,000,000us-gaap_CommonStockSharesAuthorized
Common Stock, Shares, Issued	490,923,222us-gaap_CommonStockSharesIssued	490,923,222us-gaap_CommonStockSharesIssued
Treasury Stock, Shares	66,507,690us-gaap_TreasuryStockShares	37,632,782us-gaap_TreasuryStockShares
Collateralized Debt Obligations [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets	0	31,000,000
Equity Securities [Member]
Available-for-sale Equity Securities, Amortized Cost Basis	351,000,000
Available-for-sale Securities, Equity Securities	348,000,000	0
Fixed Maturities [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets	218,000,000	161,000,000
Short-term Investments [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets	16,000,000	3,000,000
Cash [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets	9,000,000	0
Commercial Loan [Member]
Allowance for Loan and Lease Losses, Real Estate	18,000,000	67,000,000
Limited Partnerships and Other Alternative Investments [Member] \| Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity, Consolidated, Carrying Amount, Assets	3,000,000	4,000,000
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities	$ 1,000,000	$ 0

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

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