Contractual interest rate for funds borrowed, under the debt agreement.

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FINANCIAL INFORMATION FOR SUBSIDIARY GUARANTORS AND NON-GUARANTORS - Additional information (Details) - USD ($) $ in Millions	6 Months Ended
	Mar. 31, 2018	Apr. 01, 2017	Sep. 30, 2017	Dec. 15, 2016	Oct. 13, 2015
Disclosure of Dividends Paid
Revolving loan term	5 years
Return of investment from affiliates	$ 0.0	$ 0.0
Reportable Legal Entities \| Parent
Disclosure of Dividends Paid
Return of investment from affiliates	554.0	351.5
Return on investment	12.2
Reportable Legal Entities \| Subsidiary Guarantors
Disclosure of Dividends Paid
Return of investment from affiliates	0.0	$ 32.4
Return on investment	$ (1.8)
Senior Notes – 6.000% \| Senior Notes
Disclosure of Dividends Paid
Interest rate of debt	6.00%	6.00%	6.00%		6.00%
Senior Notes – 5.250% \| Senior Notes
Disclosure of Dividends Paid
Interest rate of debt	5.25%	5.25%	5.25%	5.25%