Income taxes (Details) - USD ($) |
3 Months Ended | ||
|---|---|---|---|
Mar. 31, 2017 |
Mar. 31, 2016 |
Dec. 31, 2016 |
|
| Income Tax Disclosure [Abstract] | |||
| Deferred tax assets, valuation allowance | $ 12,000,000 | ||
| Valuation allowance, change in amount | $ 0 | ||
| Provision (benefit) for income taxes | $ 16,746 | $ 65,951 | |
| Effective income tax rate | 14.70% | 10.50% | |
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. 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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| X | ||||||||||
- 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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