Derivative Instruments and Hedging Activities  - Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands  | 
3 Months Ended | |
|---|---|---|
Sep. 30, 2016  | 
Sep. 30, 2015  | 
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| Accumulated Other Comprehensive Income (Loss) | ||
| Beginning balance | $ 1,210 | $ 7,110 | 
| Amount reclassified to income | 1,379 | (402) | 
| Net change in unrealized gains or losses | (1,838) | (1,861) | 
| Ending balance | $ 751 | $ 4,847 | 
| X | ||||||||||
- Definition Accumulated Other Comprehensive Income [Roll Forward] No definition available. 
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| X | ||||||||||
- Definition Amount before tax of increase (decrease) in accumulated equity from transactions and other events and circumstances from non-owner sources, including portion attributable to noncontrolling interest. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners (distributions to owners). No definition available. 
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| X | ||||||||||
- 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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| X | ||||||||||
- 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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