Annual report pursuant to Section 13 and 15(d)

Derivative Instrument and Hedging Transactions (Realized gain (loss)) (Details)

v3.5.0.2
Derivative Instrument and Hedging Transactions (Realized gain (loss)) (Details) - USD ($)
$ in Thousands
12 Months Ended
Jun. 30, 2016
Jun. 30, 2015
Derivative [Line Items]    
Realized gains (losses) on future commodity contracts, net $ (5,861) $ (52,752)
Futures Commodity And Forwards Contracts And Open Purchase And Sale Commitments [Member]    
Derivative [Line Items]    
Unrealized losses on open future commodity and forward contracts and open sale and purchase commitments, net (7,205) (1,980)
Commodity Contract    
Derivative [Line Items]    
Realized gains (losses) on future commodity contracts, net $ 1,344 $ (50,772)