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Fair Value Measurements - Schedule of Reconciliation of Changes in Liabilities Measured at Fair Value on a Recurring Basis (Details) - Level 3 [Member] - Warrant Liability [Member] - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended
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Jun. 30, 2019 | Dec. 31, 2018
Fair value liabilities of Level 3 instruments beginning of period | $ 425 | $ 1,200
Net gain on warrant valuation | (242) | (775)
Fair value liabilities of Level 3 instruments end of period | $ 183 | $ 425

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- Definition Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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