Consolidated Balance Sheet Parentheticals (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Consolidated Balance Sheet
Fixed maturities, available for sale, amortized cost	$ 60,801	$ 62,196
Equity securities, available for sale, cost	$ 579	$ 686
Common stock, shares authorized	1,750.0us-gaap_CommonStockSharesAuthorized	1,750.0us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	322.2us-gaap_SharesIssued	353.5us-gaap_SharesIssued
Common stock, shares outstanding	322.2us-gaap_CommonStockSharesOutstanding	353.5us-gaap_CommonStockSharesOutstanding	377.4us-gaap_CommonStockSharesOutstanding	392.8us-gaap_CommonStockSharesOutstanding
Treasury stock, at cost, shares	437.3us-gaap_TreasuryStockShares	401.5us-gaap_TreasuryStockShares

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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This item represents the cost of equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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