Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014 Rate	Mar. 31, 2013 Rate	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Unrecognized Tax Benefits	$ 129		$ 130
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	105		104
Deposit To Reduce Unrecognized Tax Benefit Liabilities	46		44
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound	48
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Upper Bound	62
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	139		131
Unrecognized Tax Benefits, Income Tax Penalties Accrued	$ 17		$ 18
Effective Income Tax Rate	34.70%	37.60%