Income taxes - Uncertain tax positions (Details) - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Income taxes | ||
| Uncertain tax positions | $ 0 | $ 380 |
| Uncertain tax positions, reduction to deferred tax assets | 84 | |
| Accrued interest, net of federal income tax benefits, and penalties | 67 | |
| Reconciliation of unrecognized tax benefits | ||
| Balance at the beginning of the year | 313 | 313 |
| Additions for current period tax positions | 0 | 0 |
| Reversals during the current period | (313) | 0 |
| Balance at the end of the year | $ 0 | $ 313 |
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- References No definition available.
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns at period end. No definition available.
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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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