Income taxes (Details) - USD ($) |
3 Months Ended | 9 Months Ended | 16 Months Ended | ||
|---|---|---|---|---|---|
Sep. 30, 2016 |
Sep. 30, 2015 |
Sep. 30, 2016 |
Sep. 30, 2015 |
Sep. 30, 2016 |
|
| Income Tax Disclosure [Abstract] | |||||
| Release of valuation allowance | $ 7,700,000 | ||||
| Provision (benefit) for income taxes | $ 4,046,961 | $ (922,427) | $ 3,567,299 | $ 5,619,504 | |
| Effective income tax rate | 170.80% | (95.50%) | 91.60% | 3934.80% | |
| Net deferred tax assets | $ 13,800,000 | $ 13,800,000 | 13,800,000 | ||
| Net operating loss carryforwards | $ 6,500,000 | $ 6,500,000 | $ 6,500,000 | ||
| X | ||||||||||
- Definition Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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