Commitments and contingencies - Capital leases and notes payable and letters of credit (Details) - USD ($) $ in Thousands |
12 Months Ended | |
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Dec. 31, 2017 |
Dec. 31, 2016 |
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| Fair value | ||
| Current portion of capital leases and notes payable | $ 5,771 | $ 3,993 |
| Long-term portion of capital leases and notes payable | $ 6,747 | $ 4,612 |
| Letters of Credit | ||
| Commitments and contingencies | ||
| Term period of Letters of Credit agreements | 1 year | |
| Letters of credit | ||
| Current issued borrowing capacity | $ 8,204 | |
| Outstanding balance | $ 0 |
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- References No definition available.
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- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. No definition available.
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease, classified as current. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. No definition available.
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition No definition. No definition available.
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- Details
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