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Commitments - Summary of Lease Costs (Details) $ in Thousands | 3 Months Ended
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Mar. 31, 2019 USD ($)
Lease expense: |
Operating lease expense | $ 55
Finance lease expense: |
Depreciation of right-of-use assets | 33
Total lease expense | 88
Cash payment information: |
Operating cash used for operating leases | 55
Financing cash used for financing leases | 28
Total cash paid for amounts included in the measurement of lease liabilities | $ 83
Weighted-average remaining lease term (years) - operating leases | 7 years 3 months 18 days
Weighted-average remaining lease term (years) - finance leases | 1 year 9 months 18 days
Weighted-average discount rate - operating leases | 8.00%
Weighted-average discount rate - finance leases | 5.00%

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- Definition Amount of cash outflow for principal payment on finance lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(1) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 + Details
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