Income Taxes (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended		12 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Estimated annual effective tax rate (as a percent)	30.50%	29.00%	26.50%
Income Tax Reconciliation Non-deductible Expense Goodwill on Divestiture	$ 75
Tax benefit, repatriation of non-U.S. earnings due to available foreign tax credits in excess of the U.S. tax liability on the dividend	$ 72