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Fair Value Measurements - Schedule of Recurring Measurements of Fair Value of Assets and Liabilities (Details) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Warrants | $ 425 | $ 1,200
Recurring Measurements [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Marketable equity securities | 536 | 876
Assets: Total | 536 | 876
Warrants | 425 | 1,200
Derivatives |  | 161
Liabilities: Total | 425 | 1,361
Level 1 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Marketable equity securities | 533 | 868
Assets: Total | 533 | 868
Warrants |  |
Derivatives |  |
Liabilities: Total |  |
Level 2 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Marketable equity securities | 3 | 8
Assets: Total | 3 | 8
Warrants |  |
Derivatives |  | 161
Liabilities: Total |  | 161
Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Marketable equity securities |  |
Assets: Total |  |
Warrants | 425 | 1,200
Derivatives |  |
Liabilities: Total | $ 425 | $ 1,200

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