Significant Accounting Policies - Plant, equipment and depreciation (Details) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Property, Plant and Equipment [Line Items]
Land and land improvements	$ 321,331	$ 291,122
Buildings and building equipment	1,575,464	1,437,601
Machinery and equipment	3,167,885	2,933,818
Construction in progress	122,068	74,600
Total	$ 5,186,748	$ 4,737,141
Building
Property, Plant and Equipment [Line Items]
Useful life (in years)	40 years
Land Improvements
Property, Plant and Equipment [Line Items]
Useful life (in years)	15 years
Building Equipment
Property, Plant and Equipment [Line Items]
Useful life (in years)	15 years
Minimum | Machinery and Equipment
Property, Plant and Equipment [Line Items]
Useful life (in years)	7 years
Minimum | Vehicles and Office Equipment
Property, Plant and Equipment [Line Items]
Useful life (in years)	3 years
Maximum | Machinery and Equipment
Property, Plant and Equipment [Line Items]
Useful life (in years)	10 years
Maximum | Vehicles and Office Equipment
Property, Plant and Equipment [Line Items]
Useful life (in years)	8 years