Borrowing and Lines of Credit (Narrative) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2013
Line of Credit Facility [Line Items]
Aggregate Line of Credit Facility Maximum Borrowing Capacity	$ 4,000
Maximum Commercial Paper Borrowing Authority	4,000
Revolving Credit Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	2,000
Line of Credit Facility, Amount Outstanding	0
Line of Credit Facility, Expiration Date	Nov. 30, 2016
Multicurrency Revolving Credit Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	2,000
Line of Credit Facility, Amount Outstanding	$ 0