Valuation and qualifying accounts (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Allowance for doubtful accounts | |||
| Valuation and qualifying accounts | |||
| Balance at the beginning of the year | $ 1,158 | $ 1,343 | $ 1,667 |
| Additions charged to earnings | 1,475 | 208 | 305 |
| Changes to net | (1,577) | (393) | (629) |
| Balance at the end of the year | 1,056 | 1,158 | 1,343 |
| Valuation of deferred tax assets | |||
| Valuation and qualifying accounts | |||
| Balance at the beginning of the year | 640 | 647 | 1,600 |
| Changes to net | 137 | (7) | (953) |
| Balance at the end of the year | $ 777 | $ 640 | $ 647 |
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- Definition Total of the deductions, net of recoveries, of amounts that had previously been written off as uncollectible, in a given period to allowances and reserves, the valuation and qualifying accounts that are netted against the cost of an asset (in order to value it at its carrying value). 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 Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to costs and expenses. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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