Quarterly report pursuant to Section 13 or 15(d)

Geographic information (Details)

v3.8.0.1
Geographic information (Details) - USD ($)
 3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Dec. 31, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]          
Revenues - owned units $ 15,333,320 $ 16,317,636 $ 50,560,146 $ 45,980,270  
Management, incentive and royalty fee revenue 2,478,052 2,061,964 7,576,427 6,019,967  
United States:          
Revenues from External Customers and Long-Lived Assets [Line Items]          
Revenues - owned units 15,333,320 16,317,636 50,560,146 45,980,270  
Management, incentive and royalty fee revenue 1,565,189 1,496,612 5,102,960 4,290,779  
Net assets (1,284,784)   (1,284,784)   $ 3,899,627
Foreign:          
Revenues from External Customers and Long-Lived Assets [Line Items]          
Management, incentive and royalty fee revenue 912,863 $ 565,352 2,473,467 $ 1,729,188  
Net assets $ 5,390,750   $ 5,390,750   $ 3,478,910