Income taxes (Details 1) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Current tax expense	$ 207,728	$ 1,371
Deferred tax benefit	(365,019)	(890,348)
Income Tax Expense (Benefit)	$ (157,291)	$ (888,977)

Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations.

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-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration