Net Current and Non-Current Components of Deferred Income Taxes Recognized in the Consolidated Balance Sheets (Detail) - USD ($) $ in Millions	Sep. 30, 2015	Sep. 30, 2014
Net current deferred tax assets (classified with prepaid and other assets)	$ 78.2	$ 72.2
Net non-current deferred tax liabilities (classified with other liabilities)	125.4	120.4
Net deferred tax asset (liability)	(47.2)	(48.2)
Prepaid and other assets
Net current deferred tax assets (classified with prepaid and other assets)		72.2
Other liabilities
Net non-current deferred tax liabilities (classified with other liabilities)	$ 125.4	$ 120.4