Retirement Plans (Retirement Plans, Net Periodic Benefit Cost, Assumptions, and Expected Cash Flows) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year	$ 14
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Defined Benefit Plan, Net Periodic Benefit Cost	36	32	26
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
Number of years annual benefit payments	10 years
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year	14
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months	46
Defined Benefit Plan, Expected Future Benefit Payments, Year Two	35
Defined Benefit Plan, Expected Future Benefit Payments, Year Three	37
Defined Benefit Plan, Expected Future Benefit Payments, Year Four	36
Defined Benefit Plan, Expected Future Benefit Payments, Year Five	43
Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter	$ 341
Foreign Pension Plans, Defined Benefit
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	4.10%	4.80%
Rate of compensation increase	5.30%	5.50%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	4.80%	4.80%	5.20%
Expected long-term return on plan assets	6.40%	6.40%	6.50%
Rate of compensation increase	5.40%	5.50%	5.40%