Fair Value of Financial Instruments (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
Cash and cash equivalents [Abstract]
Cash	$ 448,200,000	$ 617,800,000
Money market funds	503,800,000	1,172,400,000
Commercial paper	5,800,000	3,900,000
Non-U.S. bank and other obligations	14,300,000	18,800,000
Short-term investments [Abstract]
U.S. Treasury securities	41,000,000	41,000,000
Non-qualified plan assets [Abstract]
Money market funds	1,100,000	1,000,000
Domestic bond funds	3,000,000	2,900,000
International bond fund	400,000	300,000
Domestic equity funds	5,800,000	5,500,000
International equity funds	2,700,000	2,700,000
Blended equity funds	4,100,000	3,800,000
Common stock	2,200,000	2,300,000
Derivatives, net asset (liability) [Abstract]
Foreign currency contracts	21,000,000	19,000,000
Total financial instruments	1,053,400,000	1,891,400,000
Fair value of the fixed-rate debt	2,690,000,000	2,660,000,000
Face value of the fixed-rate debt	2,500,000,000	2,500,000,000
Fair Value Based on Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Cash and cash equivalents [Abstract]
Cash	448,200,000	617,800,000
Money market funds	503,800,000	1,172,400,000
Commercial paper	0	0
Non-U.S. bank and other obligations	14,300,000	18,800,000
Short-term investments [Abstract]
U.S. Treasury securities	41,000,000	41,000,000
Non-qualified plan assets [Abstract]
Money market funds	1,100,000	1,000,000
Domestic bond funds	3,000,000	2,900,000
International bond fund	400,000	300,000
Domestic equity funds	5,800,000	5,500,000
International equity funds	2,700,000	2,700,000
Blended equity funds	4,100,000	3,800,000
Common stock	2,200,000	2,300,000
Derivatives, net asset (liability) [Abstract]
Foreign currency contracts	0	0
Total financial instruments	1,026,600,000	1,868,500,000
Fair Value Based on Significant Other Observable Inputs (Level 2) [Member]
Cash and cash equivalents [Abstract]
Cash	0	0
Money market funds	0	0
Commercial paper	5,800,000	3,900,000
Non-U.S. bank and other obligations	0	0
Short-term investments [Abstract]
U.S. Treasury securities	0	0
Non-qualified plan assets [Abstract]
Money market funds	0	0
Domestic bond funds	0	0
International bond fund	0	0
Domestic equity funds	0	0
International equity funds	0	0
Blended equity funds	0	0
Common stock	0	0
Derivatives, net asset (liability) [Abstract]
Foreign currency contracts	21,000,000	19,000,000
Total financial instruments	$ 26,800,000	$ 22,900,000