Business and summary of significant accounting policies - Concentrations of credit risk (Details) - USD ($) |
12 Months Ended | |
---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
|
Concentration Risk [Line Items] | ||
Cash balances in excess of federally insured limits | $ 789,157 | $ 897,383 |
Allowance for uncollectible accounts receivable | $ 0 | $ 0 |
Total Revenue | Geographic Concentration Risk | New York Downtown | ||
Concentration Risk [Line Items] | ||
Concentration risk, percentage | 9.00% | 10.00% |
Total Revenue | Geographic Concentration Risk | New York Midtown | ||
Concentration Risk [Line Items] | ||
Concentration risk, percentage | 9.00% | 9.00% |
Total Revenue | Geographic Concentration Risk | Las Vegas | ||
Concentration Risk [Line Items] | ||
Concentration risk, percentage | 17.00% | 17.00% |
Total Revenue | Geographic Concentration Risk | London | ||
Concentration Risk [Line Items] | ||
Concentration risk, percentage | 11.00% | 15.00% |
X | ||||||||||
- Definition A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
X | ||||||||||
- Definition The amount of cash as of the balance sheet date that is not insured by the Federal Deposit Insurance Corporation. No definition available.
|
X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
X | ||||||||||
- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
X | ||||||||||
- Details
|
X | ||||||||||
- Details
|
X | ||||||||||
- Details
|
X | ||||||||||
- Details
|
X | ||||||||||
- Details
|
X | ||||||||||
- Details
|