Quarterly report pursuant to Section 13 or 15(d)

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

v3.19.1
Derivative Instruments and Hedging Transactions (Realized Gain (Loss)) (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Mar. 31, 2019
Mar. 31, 2018
Derivative [Line Items]        
Gains (losses) on derivative instruments: $ 28,154 $ 11,800 $ 20,150 $ 13,819
Future commodity and forward contracts        
Derivative [Line Items]        
Unrealized gains on open future commodity and forward contracts and open sale and purchase commitments, net 27,069 15,041 15,579 5,038
Commodity Contract        
Derivative [Line Items]        
Realized gains (losses) on future commodity contracts, net $ 1,085 $ (3,241) $ 4,571 $ 8,781