Leases - Balance sheet information (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Operating lease
Operating lease right-of-use assets	$ 11,416	$ 12,645
Operating lease liabilities, current	$ 3,021	$ 2,772
Operating Lease, Liability, Current, Statement of Financial Position	leaf:AccruedAndOtherLiabilitiesCurrent	leaf:AccruedAndOtherLiabilitiesCurrent
Operating lease liabilities, noncurrent	$ 9,345	$ 10,863
Total operating lease liabilities	$ 12,366	$ 13,635
Weighted average remaining lease term, Operating lease	4 years	4 years
Weighted average discount rate, Operating lease	9.00%	9.00%

No definition available.

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Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

+ References

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Indicates line item in statement of financial position that includes current operating lease liability.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Amount of lessee's right to use underlying asset under operating lease.

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- Definition

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

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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.

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