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Concentrations of Credit Risk - Schedule of Credit Risk (Details) - Net revenue - Major Customers | 12 Months Ended
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Jun. 30, 2016 | Jun. 30, 2015 | Jun. 30, 2014
Concentrations of Credit Risk |  |  |
Percent of Total Revenue | 100.00% | 100.00% | 100.00%
Plains Marketing L.P. (includes Delhi production) |  |  |
Concentrations of Credit Risk |  |  |
Percent of Total Revenue | 99.00% | 99.00% | 96.00%
Enterprise Crude Oil LLC |  |  |
Concentrations of Credit Risk |  |  |
Percent of Total Revenue | 0.00% | 0.00% | 2.00%
Flint Hills |  |  |
Concentrations of Credit Risk |  |  |
Percent of Total Revenue | 0.00% | 0.00% | 1.00%
ETC Texas Pipeline, LTD. |  |  |
Concentrations of Credit Risk |  |  |
Percent of Total Revenue | 0.00% | 0.00% | 1.00%
All others |  |  |
Concentrations of Credit Risk |  |  |
Percent of Total Revenue | 1.00% | 1.00% | 0.00%

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