| Derivative Instruments and Hedging Activities  - Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
| Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2015 | Dec. 31, 2014 | |
| Accumulated Other Comprehensive Income (Loss) | ||||
| Beginning balance | $ 4,847 | $ 1,785 | $ 7,110 | $ (20) | 
| Amount reclassified to income | 165 | (1,584) | (237) | (1,812) | 
| Net change in unrealized gains or losses | 707 | 11,924 | (1,154) | 13,957 | 
| Ending balance | $ 5,719 | $ 12,125 | $ 5,719 | $ 12,125 | 
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- Definition Accumulated Other Comprehensive Income (Loss), Cumulative Changes In Net Gain (Loss) From Cash Flow Hedges No definition available. 
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- Definition Accumulated Other Comprehensive Income [Roll Forward] No definition available. 
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- Definition The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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