Leases - Terms and discount rate (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
Leases
Weighted average remaining lease term in years	6 years 5 months 19 days
Weighted-average incremental borrowing rate	13.55%
Supplemental disclosure of cash flow information related to operating leases
Cash paid for amounts included in the measurement of lease liabilities	$ 2,215

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- References

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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- Definition

Weighted average discount rate for operating lease calculated at point in time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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