Income Taxes - Indefinite Reinvestment of Foreign Earnings (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Income Taxes [Abstract]
Increase to shareholders' net income resulting from indefinite reinvestment of foreign earnings	$ 10	$ 12
Accumulated permanently reinvested foreign earnings	1,200
Cumulative unrecognized deferred tax liabilities	$ 168

Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant