Business and summary of significant accounting policies - Impairment of long-lived assets (Details) - USD ($) |
12 Months Ended | |
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Dec. 31, 2015 |
Dec. 31, 2014 |
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| Property, Plant and Equipment [Line Items] | ||
| Impairment loss | $ 2,975,744 | $ 0 |
| Discontinued Operations [Member] | ||
| Property, Plant and Equipment [Line Items] | ||
| Impairment loss | $ 468,000 | |
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- Definition The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- 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.
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- Details
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