Derivatives and Hedging Activities - Narrative (Details) lb in Millions	12 Months Ended
	Jun. 30, 2018 USD ($) lb	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)
Derivative Instruments, Gain (Loss) [Line Items]
Derivative contracts on a gross basis	$ 41,700,000
Derivative contracts liability on a gross basis	9,900,000
Cash collateral held by counterparties	0
Derivative losses included in AOCI	15,400,000
Cash flow hedges
Derivative Instruments, Gain (Loss) [Line Items]
Net gains recorded as a reduction to interest expense	$ 41,000,000	$ 9,300,000	$ (33,300,000)
Commodity contracts | Cash flow hedges
Derivative Instruments, Gain (Loss) [Line Items]
Amounts of raw materials to be purchased from forward contracts (in lb) | lb	23.2
Net gains recorded as a reduction to interest expense	$ 41,400,000	9,400,000	(34,000,000)
Forward interest rate swaps | Cash flow hedges | Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Net gains recorded as a reduction to interest expense	300,000	300,000	300,000
Forward interest rate swaps | Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Total notional amounts of interest rate contracts	150,000,000	150,000,000
Net gains recorded as a reduction to interest expense	$ 400,000	$ 1,800,000	$ 2,600,000