Segment information - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Retail [Member]
Segment Reporting Information [Line Items]
Depreciation, Depletion and Amortization	$ 596,528	$ 617,671	$ 1,796,588	$ 1,751,048
Bulk [Member]
Segment Reporting Information [Line Items]
Depreciation, Depletion and Amortization	971,914	933,955	2,906,213	2,858,081
Services [Member]
Segment Reporting Information [Line Items]
Depreciation, Depletion and Amortization	191,419	0	562,756	0
Manufacturing Units [Member]
Segment Reporting Information [Line Items]
Depreciation, Depletion and Amortization	$ 88,452	$ 214,751	$ 296,926	$ 707,517