Discontinued operations - Mexico project development (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Current assets	$ 1,052,091	$ 1,619,056
Total assets of discontinued operations	23,047,739	29,289,022
Discontinued Operations | Mexico Project Development
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Current assets	1,052,091	1,619,056
Property, plant and equipment, net	6,818	10,227
Land and rights of way	21,126,898	24,162,523
Other assets	861,932	3,497,216
Total assets of discontinued operations	23,047,739	29,289,022
Total liabilities of discontinued operations	$ 107,733	$ 2,858,314