Annual report pursuant to Section 13 and 15(d)

Derivative Instruments and Hedging Transactions (Realized Gain (Loss)) (Details)

v3.19.2
Derivative Instruments and Hedging Transactions (Realized Gain (Loss)) (Details) - USD ($)
$ in Thousands
12 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Derivative [Line Items]    
Gains (losses) on derivative instruments: $ (1,068) $ 15,622
Future commodity and forward contracts    
Derivative [Line Items]    
Unrealized (losses) gains on open future commodity and forward contracts and open sale and purchase commitments, net (126) 2,351
Commodity Contract    
Derivative [Line Items]    
Realized (losses) gains on future commodity contracts, net $ (942) $ 13,271