Summary of significant accounting policies - Foreign currency translation (Details) - USD ($) $ in Thousands |
Mar. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Foreign Currency Translation | ||
| Cumulative foreign currency translation adjustments, net of tax in accumulated other comprehensive income | $ (899) | $ (898) |
| Income tax effect related to foreign currency translation adjustments | $ 0 | $ 0 |
| X | ||||||||||
- Definition Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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- Definition Tax affect of the accumulated adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses. No definition available.
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