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           Business and summary of significant accounting policies (Concentrations of credit risk) (Details) (USD $) 
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        12 Months Ended | ||||||
|---|---|---|---|---|---|---|---|
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           Dec. 31, 2013 
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           Dec. 31, 2012 
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           Dec. 31, 2011 
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           Dec. 31, 2013
 
          Accounts Receivable [Member]
 
          Hotels [Member] 
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           Dec. 31, 2012
 
          Accounts Receivable [Member]
 
          Hotels [Member] 
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           Dec. 31, 2013
 
          Accounts Receivable [Member]
 
          Landlord at Midtown [Member] 
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           Dec. 31, 2012
 
          Accounts Receivable [Member]
 
          Landlord at Midtown [Member] 
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      |
| Concentration Risk [Line Items] | |||||||
| Concentration Risk, Percentage | 66.00% | 65.00% | 11.00% | 6.00% | |||
| Allowance for Doubtful Accounts Receivable, Current | $ 164,004 | $ 164,004 | |||||
| Cash, Uninsured Amount | $ 11,147,927 | $ 352,482 | |||||
| X | ||||||||||
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- 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 
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- Definition 
          The amount of cash as of the balance sheet date that is not insured by the Federal Deposit Insurance Corporation. No definition available. 
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- Details 
          
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- 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 
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