Fair Value Measurements (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Assets:
Short-term investments	$ 8.2		$ 12.4
Deferred compensation assets	4.5		4.0
Foreign currency contracts	0.2
Commodity contracts	0.1
Total assets at fair value	13.0		16.4
Liabilities:
Contingent consideration	3.3		3.3
Deferred compensation liabilities	8.8		7.6
Interest rate swap contracts	7.9		8.6
Foreign currency contracts	3.1		1.4
Long-term debt	435.3		386.0
Total liabilities at fair value	458.4		406.9
Other Financial Instruments [Abstract]
Long-term debt	428.4		378.8
Level 3 Fair Value Measurements [Roll Forward]
Balance, beginning of period	3.3	2.1
Increase in fair value recorded in earnings	0	(0.2)
Balance, end of period	3.3	2.3
Level 1 [Member]
Assets:
Short-term investments	8.2		12.4
Deferred compensation assets	4.5		4.0
Foreign currency contracts	0
Commodity contracts	0
Total assets at fair value	12.7		16.4
Liabilities:
Contingent consideration	0		0
Deferred compensation liabilities	8.8		7.6
Interest rate swap contracts	0		0
Foreign currency contracts	0		0
Long-term debt	0		0
Total liabilities at fair value	8.8		7.6
Level 2 [Member]
Assets:
Short-term investments	0		0
Deferred compensation assets	0		0
Foreign currency contracts	0.2
Commodity contracts	0.1
Total assets at fair value	0.3		0
Liabilities:
Contingent consideration	0		0
Deferred compensation liabilities	0		0
Interest rate swap contracts	7.9		8.6
Foreign currency contracts	3.1		1.4
Long-term debt	435.3		386.0
Total liabilities at fair value	446.3		396.0
Level 3 [Member]
Assets:
Short-term investments	0		0
Deferred compensation assets	0		0
Foreign currency contracts	0
Commodity contracts	0
Total assets at fair value	0		0
Liabilities:
Contingent consideration	3.3		3.3
Deferred compensation liabilities	0		0
Interest rate swap contracts	0		0
Foreign currency contracts	0		0
Long-term debt	0		0
Total liabilities at fair value	$ 3.3		$ 3.3