Financing Agreements (Details) In Millions, unless otherwise specified				3 Months Ended		6 Months Ended			3 Months Ended		6 Months Ended
	Mar. 31, 2014 USD ($)	Sep. 30, 2013 USD ($)	Mar. 31, 2013 USD ($)	Mar. 31, 2014 $700 revolving credit facility (excludes outstanding letters of credit) USD ($)	Mar. 31, 2013 $700 revolving credit facility (excludes outstanding letters of credit)	Mar. 31, 2014 $700 revolving credit facility (excludes outstanding letters of credit) USD ($)	Mar. 31, 2013 $700 revolving credit facility (excludes outstanding letters of credit)	Sep. 30, 2013 $700 revolving credit facility (excludes outstanding letters of credit) USD ($)	Mar. 31, 2014 $200 term loan USD ($)	Mar. 31, 2013 $200 term loan	Mar. 31, 2014 $200 term loan USD ($)	Mar. 31, 2013 $200 term loan	Sep. 30, 2013 $200 term loan USD ($)	Mar. 31, 2014 $150 senior unsecured notes, due July 15, 2020, net of discount USD ($)	Sep. 30, 2013 $150 senior unsecured notes, due July 15, 2020, net of discount USD ($)	Mar. 31, 2014 Other financing agreements USD ($)	Mar. 31, 2014 Syndicated Letter of Guarantee Facility EUR (€)
Financing Agreements
Other borrowings	$ 1.0
Total debt	626.1	664.3		291.2		291.2		325.5	185.0		185.0		190.0	148.9	148.8
Less: current portion	13.5	10.0
Total long-term debt	612.6	654.3
Maximum borrowing capacity available under the facility				700.0		700.0		700.0								291.6	150.0
Debt issued								200	200		200			150	150
Letters of credit outstanding				15.2		15.2
Maximum borrowing capacity available under the credit facility				393.6		393.6
Current borrowing capacity available under the facility				283		283
Weighted average interest rates (as a percent)				1.37%	1.39%	1.36%	1.38%		1.66%	1.71%	1.67%	1.74%
Restricted cash	0.5		1.3
Amount of credit facility utilized for providing bank guarantees																$ 217.3