| Intangible assets, net - Aggregate Amortization Expense (Details) $ in Thousands | Jun. 30, 2016  USD ($) | 
|---|---|
| Estimated aggregate amortization expense | |
| Estimated aggregate amortization expense, year ended June 30, 2017 | $ 145 | 
| Estimated aggregate amortization expense, year ended June 30, 2018 | 85 | 
| Estimated aggregate amortization expense, year ended June 30, 2019 | 33 | 
| Estimated aggregate amortization expense, year ended June 30, 2020 | 21 | 
| Estimated aggregate amortization expense, year ended June 30, 2021 | $ 21 | 
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- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available. 
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- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available. 
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- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the fourth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available. 
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- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the third rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available. 
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- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the second rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available. 
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- References No definition available. 
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