Debt (Details Textuals) (USD $)	9 Months Ended		9 Months Ended		9 Months Ended
	Sep. 30, 2014 Institutions	Dec. 31, 2013	Sep. 30, 2014 Unsecured Medium Term Notes Due September 2019 [Domain]	May 31, 2014 Unsecured Medium Term Notes Due September 2019 [Domain]	Sep. 30, 2014 Unsecured Medium Term Notes Due June 2019 [Member]	Feb. 28, 2014 Unsecured Medium Term Notes Due June 2019 [Member]	Sep. 30, 2014 Global Revolving Credit Facility [Member]	Sep. 30, 2014 Letter of Credit [Member]
Line of Credit Facility [Abstract]
Maximum borrowing capacity under global revolving credit facility							$ 900,000,000	$ 75,000,000
Number of lending institutions	12
Letter of credit outstanding amount								0
Annual facility fees minimum	0.80%
Annual facility fees maximum	2.75%
Global Revolving Credit Facility Unused Capacity Commitment Fee Percent	1.25%
Ratio of Indebtedness to Net Capital	3
Global revolving credit facility covenant terms, debt to consolidated tangible net worth ratio	less than or equal to 300%
Debt to consolidated tangible net worth ratio	184.00%
Line of credit remaining capacity	564,000,000
Commercial paper classified as long term debt	333,000,000	498,200,000
Face amount of unsecured medium-term notes issued				400,000,000		350,000,000
Repurchase price condition of notes			101% of principal plus accrued and unpaid interest		101% of principal plus accrued and unpaid interest
Debt repurchase price, percentage			101.00%		101.00%
Total available proceeds under trade receivables purchase and sale program	175,000,000
Number of days under trade receivables purchase and sale program	364 days
Trade Receivables Purchase And Sale Program Amounts Outstanding	0	0
Current Maturities Classified as Long Term Debt	250,000,000	564,000,000
Letters Of Credit And Surety Bonds Outstanding	$ 316,600,000	$ 310,500,000