Contingencies and commitments - Lease Expenses (Details) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Contingencies and commitments | |||
| Lease expenses | $ 3,399,000 | $ 3,617,000 | $ 2,255,000 |
| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line. No definition available.
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