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Income taxes (Details 2) (USD $)
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12 Months Ended | ||
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Dec. 31, 2011
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Dec. 31, 2012
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Dec. 31, 2010
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| Income taxes | |||
| Uncertain tax positions, reduction to deferred tax assets | $ 106,000 | ||
| Changes in uncertain tax positions | |||
| Balance at the beginning of the period | 106,000 | 392,000 | |
| Additions for current period tax positions | 286,000 | ||
| Balance at the end of the period | 392,000 | 392,000 | |
| Accrued interest or penalties | $ 0 | $ 0 | $ 0 |
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- Details
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- Details
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- Definition
The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
This element represents the total of accruals as of the date of the statement of financial position for interest recognized for an underpayment of income taxes computed by applying the applicable statutory rate of interest to the difference between a tax position recognized for financial reporting purposes and the amount previously taken or expected to be taken in a tax return of the entity and the amount of statutory penalties for a tax position claimed or expected to be claimed by the entity, in its tax return, that does not meet the minimum statutory threshold to avoid payment of penalties. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Represents the amount of uncertain tax positions, which is a reduction to deferred tax assets that is presented as net of uncertain tax positions in the accompanying consolidated balance sheets. No definition available.
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