Assets and Liabilities, at Fair Value (Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Jun. 30, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	$ 17,587	$ 33,732
Derivative liabilities	34,582	36,454
Fair Value on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Inventory	284,619	245,041
Total assets valued at fair value	302,206	278,773
Other long-term liabilities	5,625	4,352
Product financing arrangement	135,343	59,358
Contingent earn-out liability	1,325
Total liabilities, valued at fair value	176,875	100,164
Fair Value on a Recurring Basis | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Inventory	284,619	245,041
Total assets valued at fair value	302,206	278,773
Other long-term liabilities	5,625	4,352
Product financing arrangement	135,343	59,358
Contingent earn-out liability	0
Total liabilities, valued at fair value	175,550	100,164
Fair Value on a Recurring Basis | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Inventory	0	0
Total assets valued at fair value	0	0
Other long-term liabilities	0	0
Product financing arrangement	0	0
Contingent earn-out liability	0
Total liabilities, valued at fair value	0	0
Fair Value on a Recurring Basis | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Inventory	0	0
Total assets valued at fair value	0	0
Other long-term liabilities	0	0
Product financing arrangement	0	0
Contingent earn-out liability	1,325
Total liabilities, valued at fair value	1,325	0
Liability on margin accounts | Fair Value on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	4,797	8,182
Liability on margin accounts | Fair Value on a Recurring Basis | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	4,797	8,182
Liability on margin accounts | Fair Value on a Recurring Basis | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0	0
Liability on margin accounts | Fair Value on a Recurring Basis | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0	0
Open sale and purchase commitments | Fair Value on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	29,785	1,919
Open sale and purchase commitments | Fair Value on a Recurring Basis | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	29,785	1,919
Open sale and purchase commitments | Fair Value on a Recurring Basis | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0	0
Open sale and purchase commitments | Fair Value on a Recurring Basis | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities	0	0
Future contracts | Fair Value on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		13,914
Future contracts | Fair Value on a Recurring Basis | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		13,914
Future contracts | Fair Value on a Recurring Basis | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		0
Future contracts | Fair Value on a Recurring Basis | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		0
Forward contracts | Fair Value on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		12,439
Forward contracts | Fair Value on a Recurring Basis | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		12,439
Forward contracts | Fair Value on a Recurring Basis | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		0
Forward contracts | Fair Value on a Recurring Basis | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative liabilities		0
Derivative Asset Open Purchases And Sales Commitments | Fair Value on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	931	32,347
Derivative Asset Open Purchases And Sales Commitments | Fair Value on a Recurring Basis | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	931	32,347
Derivative Asset Open Purchases And Sales Commitments | Fair Value on a Recurring Basis | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Derivative Asset Open Purchases And Sales Commitments | Fair Value on a Recurring Basis | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Future contracts | Fair Value on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	1,273
Future contracts | Fair Value on a Recurring Basis | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	1,273
Future contracts | Fair Value on a Recurring Basis | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0
Future contracts | Fair Value on a Recurring Basis | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0
Forward contracts | Fair Value on a Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	15,383	1,385
Forward contracts | Fair Value on a Recurring Basis | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	15,383	1,385
Forward contracts | Fair Value on a Recurring Basis | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	0	0
Forward contracts | Fair Value on a Recurring Basis | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	$ 0	$ 0