Fair Value Measurements-Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions	Feb. 29, 2016	Nov. 30, 2015	May. 31, 2015	Feb. 28, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt	$ 1,056.9	$ 1,256.2		$ 1,012.5
Long-term Debt, Fair Value	1,147.3	1,325.6		1,107.8
Liabilities [Abstract]
Contingent consideration related to acquisition	28.4	27.1	$ 27.7
Recurring [Member]
Assets [Abstract]
Cash and cash equivalents	111.8	112.6		81.8
Insurance contracts	97.7	104.1		106.8
Bonds and other long-term investments	9.2	8.5		7.8
Interest rate derivatives	4.5	2.5		4.9
Foreign currency derivatives	4.4	3.4		8.4
Total assets	227.6	231.1		209.7
Liabilities [Abstract]
Foreign currency derivatives	1.8	0.7		3.4
Interest rate derivatives		0.6
Contingent consideration related to acquisition	28.4	27.1
Total liabilities	30.2	28.4
Recurring [Member] | Level 1 [Member]
Assets [Abstract]
Cash and cash equivalents	111.8	112.6		81.8
Insurance contracts	0.0	0.0		0.0
Bonds and other long-term investments	9.2	8.5		7.8
Interest rate derivatives	0.0	0.0		0.0
Foreign currency derivatives	0.0	0.0		0.0
Total assets	121.0	121.1		89.6
Liabilities [Abstract]
Foreign currency derivatives	0.0	0.0		0.0
Total liabilities	0.0	0.0
Recurring [Member] | Level 2 [Member]
Assets [Abstract]
Cash and cash equivalents	0.0	0.0		0.0
Insurance contracts	97.7	104.1		106.8
Bonds and other long-term investments	0.0	0.0		0.0
Interest rate derivatives	4.5	2.5		4.9
Foreign currency derivatives	4.4	3.4		8.4
Total assets	106.6	110.0		120.1
Liabilities [Abstract]
Foreign currency derivatives	1.8	0.7		3.4
Interest rate derivatives		0.6
Total liabilities	1.8	1.3
Recurring [Member] | Level 3 [Member]
Assets [Abstract]
Cash and cash equivalents	0.0	0.0		0.0
Insurance contracts	0.0	0.0		0.0
Bonds and other long-term investments	0.0	0.0		0.0
Interest rate derivatives	0.0	0.0		0.0
Foreign currency derivatives	0.0	0.0		0.0
Total assets	0.0	0.0		0.0
Liabilities [Abstract]
Foreign currency derivatives	0.0	0.0		$ 0.0
Contingent consideration related to acquisition	28.4	27.1
Total liabilities	$ 28.4	$ 27.1