Financing Agreements - Schedule of borrowings (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 15, 2014	Sep. 30, 2014
Financing Agreements
Total debt	$ 530.3		$ 558.5
Less: current portion	(11.2)		(15.0)
Long-term debt	519.1		543.5
$700 revolving credit facility, maturing December 19, 2019
Financing Agreements
Total debt	105.8		229.6
$180 term loan, final maturity December 19, 2019
Financing Agreements
Total debt	173.2		180.0
$150 senior unsecured notes, due July 15, 2020, net of discount
Financing Agreements
Total debt	149.1		148.9
$100 unsecured Series A Notes, due December 15, 2024
Financing Agreements
Total debt	100.0	$ 100.0	0.0
Stated interest rate		4.60%
Borrowings [Member]
Financing Agreements
Total debt	$ 2.2		$ 0.0