Condensed Consolidating Information - Consolidating cash flow statement (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Condensed Cash Flow Statements
Net cash provided by (used in) operating activities	$ 10.2	$ 82.2
Investing activities:
Capital expenditures	(11.9)	(11.4)
Proceeds from sales of property, plant, and equipment	0.5	0.7
Proceeds from warrant exercise		5.7
Other, net	(1.1)	0.9
Net cash used in investing activities	(12.5)	(4.1)
Financing activities:
Repayments on term loan	(4.5)	(5.0)
Proceeds from revolving credit facilities	254.4	182.6
Repayments on revolving credit facilities	(332.0)	(218.6)
Proceeds from unsecured Series A Notes, net of financing costs	99.6	0
Proceeds from other borrowings	0	1.0
Payment of dividends on common stock	(25.2)	(24.8)
Repurchases of common stock	(9.2)	(16.5)
Net proceeds on stock plans	3.4	12.7
Other, net	1.2	0.1
Net cash used in financing activities	(12.3)	(68.5)
Effect of exchange rates on cash and cash equivalents	(0.4)	(1.3)
Net cash flows	(15.0)	8.3
At beginning of period	58.0	42.7
At end of period	43.0	51.0
Reportable legal entities | Parent
Condensed Cash Flow Statements
Net cash provided by (used in) operating activities	12.7	13.0
Investing activities:
Capital expenditures	(0.8)	(0.8)
Proceeds from sales of property, plant, and equipment		0
Other, net		0
Net cash used in investing activities	(0.8)	(0.8)
Financing activities:
Repayments on term loan	(4.5)	(5.0)
Proceeds from revolving credit facilities	191.0	158.0
Repayments on revolving credit facilities	(268.5)	(137.5)
Proceeds from unsecured Series A Notes, net of financing costs	99.6
Payment of dividends on common stock	(25.2)	(24.8)
Repurchases of common stock	(9.2)	(16.5)
Net proceeds on stock plans	3.4	12.7
Other, net	1.2	0.9
Net cash used in financing activities	(12.2)	(12.2)
Net cash flows	(0.3)	0
At beginning of period	0.4
At end of period	0.1	0.6
Reportable legal entities | Guarantors
Condensed Cash Flow Statements
Net cash provided by (used in) operating activities	84.8	37.2
Investing activities:
Capital expenditures	(7.2)	(6.4)
Proceeds from sales of property, plant, and equipment	0.5	0.7
Proceeds from warrant exercise		5.7
Other, net	(0.9)
Net cash used in investing activities	(7.6)	0
Financing activities:
Payment of dividends - intercompany	(80.3)	(38.4)
Net cash used in financing activities	(80.3)	(38.4)
Net cash flows	(3.1)	(1.2)
At beginning of period	10.6
At end of period	7.5	7.5
Reportable legal entities | Non-Guarantors
Condensed Cash Flow Statements
Net cash provided by (used in) operating activities	(1.7)	79.3
Investing activities:
Capital expenditures	(3.9)	(4.2)
Other, net	(0.2)	0.9
Net cash used in investing activities	(4.1)	(3.3)
Financing activities:
Proceeds from revolving credit facilities	63.4	24.6
Repayments on revolving credit facilities	(63.5)	(81.1)
Proceeds from unsecured Series A Notes, net of financing costs	0
Proceeds from other borrowings		1.0
Payment of dividends - intercompany	(5.3)	(8.9)
Other, net	0	(0.8)
Net cash used in financing activities	(5.4)	(65.2)
Effect of exchange rates on cash and cash equivalents	(0.4)	(1.3)
Net cash flows	(11.6)	9.5
At beginning of period	47.0
At end of period	35.4	42.9
Eliminations
Condensed Cash Flow Statements
Net cash provided by (used in) operating activities	(85.6)	(47.3)
Financing activities:
Payment of dividends - intercompany	85.6	47.3
Net cash used in financing activities	$ 85.6	$ 47.3