Derivative Financial Instruments - Fair Value of Outstanding Derivative Contracts in Condensed Consolidated Balance Sheets (Detail) - USD ($) $ in Millions	Sep. 30, 2016	Jun. 30, 2016	Sep. 30, 2015
Derivatives designated as hedging instruments
Derivatives, Fair Value [Line Items]
Total asset derivatives	$ 8.5		$ 5.6
Total liability derivatives	3.0		9.6
Derivatives designated as hedging instruments | Interest Rate Contract [Member] | Accounts payable and other current liabilities
Derivatives, Fair Value [Line Items]
Total liability derivatives	0.7		1.4
Derivatives designated as hedging instruments | Interest Rate Contract [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Total liability derivatives	0.4		1.2
Derivatives designated as hedging instruments | Commodity swap and option agreements | Receivables, net
Derivatives, Fair Value [Line Items]
Total asset derivatives	2.9		0.0
Derivatives designated as hedging instruments | Foreign exchange forward agreements | Other assets
Derivatives, Fair Value [Line Items]
Total asset derivatives	0.1		0.4
Derivatives designated as hedging instruments | Foreign exchange contracts | Receivables, net
Derivatives, Fair Value [Line Items]
Total asset derivatives	5.5		5.2
Derivatives designated as hedging instruments | Foreign exchange contracts | Accounts payable and other current liabilities
Derivatives, Fair Value [Line Items]
Total liability derivatives	1.7		1.5
Derivatives designated as hedging instruments | Foreign exchange contracts | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Total liability derivatives	0.1		0.0
Derivatives designated as hedging instruments | Commodity contracts | Accounts payable and other current liabilities
Derivatives, Fair Value [Line Items]
Total liability derivatives	0.1		4.7
Derivatives designated as hedging instruments | Commodity contracts | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Total liability derivatives	0.0		0.8
Derivatives not designated as hedging instrument
Derivatives, Fair Value [Line Items]
Total asset derivatives	25.9		12.4
Total liability derivatives	134.4		163.1
Derivatives not designated as hedging instrument | Foreign exchange forward agreements | Accounts payable and other current liabilities
Derivatives, Fair Value [Line Items]
Total liability derivatives	0.2		0.1
Derivatives not designated as hedging instrument | Foreign exchange contracts | Receivables, net
Derivatives, Fair Value [Line Items]
Total asset derivatives	0.2		0.4
Derivatives not designated as hedging instrument | Foreign exchange contracts | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Total liability derivatives	0.0		11.0
Derivatives not designated as hedging instrument | Commodity contracts | Accounts payable and other current liabilities
Derivatives, Fair Value [Line Items]
Total liability derivatives	0.0		0.1
Derivatives not designated as hedging instrument | Call options | Other assets
Derivatives, Fair Value [Line Items]
Total asset derivatives	5.9		1.0
Derivatives not designated as hedging instrument | Call options | Funds withheld for reinsurance liability [Member]
Derivatives, Fair Value [Line Items]
Total asset derivatives	$ 11.3		5.4
Derivatives not designated as hedging instrument | Futures contracts | Accounts payable and other current liabilities
Derivatives, Fair Value [Line Items]
Total liability derivatives		$ 131.2	$ 142.3