Long-Term Debt (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Nov. 30, 2014	Dec. 31, 2015	Dec. 31, 2014	May. 31, 2015
Debt
Less deferred debt issuance costs		$ (13.3)	$ (17.7)
Total debt, Carrying Amount		2,813.5	2,656.2
Less current portion		0.3	1.6
Total long-term debt		2,813.2	2,654.6
Total debt, Approximate Fair Value		2,828.5	2,704.0
Less short-term debt, Approximate Fair Value		(0.3)	(1.6)
Long-term debt, Approximate Fair Value		2,828.2	2,702.4
Issuance costs			11.1
Maturity of the Company's long-term debt over each of the next five years
2016		0.3
2017		375.0
2018		826.9
2019		749.4
2020		0.1
Thereafter		875.1
Total debt (exclusive of unamortized deferred debt issuance costs)		$ 2,826.8
Revolving Credit Facility
Debt
Base of interest spread		LIBOR
Maximum borrowing capacity		$ 1,500.0
Credit Agreement due 2015
Debt
Maximum borrowing capacity				$ 200.0
Commercial Paper
Debt
Total debt, Carrying Amount		823.9	671.0
Total debt, Approximate Fair Value		823.9	671.0
Unamortized discount		0.2	0.4
Maximum amount outstanding at any time		$ 1,500.0
Average Interest Rate (as a percent)		0.88%
Maximum maturity term		397 days
Maximum borrowing capacity		$ 1,500.0
Senior Notes
Debt
Redemption price as a percentage of principal amount		100.00%
4.75% Senior Notes due November 2014
Debt
Repayments of Debt	$ 600.0
4.00% Senior Notes due February 2022
Debt
Total debt, Carrying Amount		$ 499.2	499.1
Total debt, Approximate Fair Value		$ 508.6	524.5
Stated interest rate (as a percent)		4.00%
Unamortized discount		$ 0.8	0.9
2.55% Senior Notes due January 2019
Debt
Total debt, Carrying Amount		749.2	749.1
Total debt, Approximate Fair Value		$ 750.1	754.9
Stated interest rate (as a percent)		2.55%
Unamortized discount		$ 0.7	0.9
Debt instrument, principal amount		$ 750.0
Debt instrument, face amount, net of discount (as a percent)		99.846%
1.55% Senior Notes due September 2017
Debt
Total debt, Carrying Amount		$ 374.8	374.7
Total debt, Approximate Fair Value		$ 373.2	373.0
Stated interest rate (as a percent)		1.55%
Unamortized discount		$ 0.2	0.3
Debt instrument, principal amount		$ 375.0
Debt instrument, face amount, net of discount (as a percent)		99.898%
3.125% Senior Notes due September 2021
Debt
Total debt, Carrying Amount		$ 374.7	374.7
Total debt, Approximate Fair Value		$ 367.7	375.3
Stated interest rate (as a percent)		3.125%
Unamortized discount		$ 0.3	0.3
Debt instrument, principal amount		$ 375.0
Debt instrument, face amount, net of discount (as a percent)		99.912%
Notes payable to foreign banks and other debt
Debt
Total debt, Carrying Amount		$ 5.0	5.3
Total debt, Approximate Fair Value		5.0	$ 5.3
Uncommitted standby letter of credit facility
Debt
Credit facility issued as of year end		12.3
Maximum borrowing capacity		$ 20.0