CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Common shares, par value (in dollars per share)	$ 0.01	$ 0.01
Common shares, shares authorized	1,250,000,000us-gaap_CommonStockSharesAuthorized	1,250,000,000us-gaap_CommonStockSharesAuthorized
Common shares, shares issued	320,990,255us-gaap_CommonStockSharesIssued	316,816,851us-gaap_CommonStockSharesIssued
Treasury shares	137,880,746us-gaap_TreasuryStockShares	124,698,544us-gaap_TreasuryStockShares
Consolidated investment entities [Member]
Receivables, fair value (in dollars)	$ 49	$ 32
Debt, fair value (in dollars)	6,030	4,804
Other liabilities, fair value (in dollars)	$ 193	$ 193

Face amount or stated value per share of common stock.

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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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