Derivative Financial Instruments (Details) - USD ($) $ in Millions	Apr. 30, 2020	Apr. 30, 2019
Other Current Assets [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Assets	$ 17.1	$ 6.2
Other Current Assets [Member] | Designated as Hedging Instrument [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Assets		0.0
Other Current Assets [Member] | Not designated as hedging instruments [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Assets		6.2
Other Current Assets [Member] | Interest Rate Contract [Member] | Designated as Hedging Instrument [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Assets		0.0
Other Current Assets [Member] | Commodity contracts [Member] | Not designated as hedging instruments [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Assets	14.7	4.8
Other Current Assets [Member] | Foreign currency exchange contracts [Member] | Not designated as hedging instruments [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Assets	2.4	1.4
Other Current Liabilities [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Liabilities	33.3	75.1
Other Current Liabilities [Member] | Designated as Hedging Instrument [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Liabilities		49.1
Other Current Liabilities [Member] | Not designated as hedging instruments [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Liabilities		26.0
Other Current Liabilities [Member] | Interest Rate Contract [Member] | Designated as Hedging Instrument [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Liabilities		49.1
Other Current Liabilities [Member] | Commodity contracts [Member] | Not designated as hedging instruments [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Liabilities	33.2	25.8
Other Current Liabilities [Member] | Foreign currency exchange contracts [Member] | Not designated as hedging instruments [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Liabilities	0.1	0.2
Other Noncurrent Assets [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Assets	0.0	0.0
Other Noncurrent Assets [Member] | Designated as Hedging Instrument [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Assets		0.0
Other Noncurrent Assets [Member] | Not designated as hedging instruments [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Assets		0.0
Other Noncurrent Assets [Member] | Interest Rate Contract [Member] | Designated as Hedging Instrument [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Assets		0.0
Other Noncurrent Assets [Member] | Commodity contracts [Member] | Not designated as hedging instruments [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Assets	0.0	0.0
Other Noncurrent Assets [Member] | Foreign currency exchange contracts [Member] | Not designated as hedging instruments [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Assets	0.0	0.0
Other Noncurrent Liabilities [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Liabilities	0.0	0.0
Other Noncurrent Liabilities [Member] | Designated as Hedging Instrument [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Liabilities		0.0
Other Noncurrent Liabilities [Member] | Not designated as hedging instruments [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Liabilities		0.0
Other Noncurrent Liabilities [Member] | Interest Rate Contract [Member] | Designated as Hedging Instrument [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Liabilities		0.0
Other Noncurrent Liabilities [Member] | Commodity contracts [Member] | Not designated as hedging instruments [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Liabilities	0.0	0.0
Other Noncurrent Liabilities [Member] | Foreign currency exchange contracts [Member] | Not designated as hedging instruments [Member]
Fair value of derivative instruments [Line Items]
Derivatives Instruments, Liabilities	$ 0.0	$ 0.0