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Fair Value Measurements - Schedule of Recurring Measurements of Fair Value of Assets and Liabilities (Details) - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020
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Recurring Measurements [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of assets | $ 340 | $ 181
Marketable Equity Securities [Member] | Recurring Measurements [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of assets | 231 | 181
Commodity Derivatives [Member] | Recurring Measurements [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of assets | 109 |
Warrants [Member] | Recurring Measurements [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of liabilities | 115 | 95
Level 1 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of assets | 231 | 181
Level 1 [Member] | Marketable Equity Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of assets | 231 | 181
Level 1 [Member] | Commodity Derivatives [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of assets |  |
Level 1 [Member] | Warrants [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of liabilities |  |
Level 2 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of assets | 109 |
Level 2 [Member] | Marketable Equity Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of assets |  |
Level 2 [Member] | Commodity Derivatives [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of assets | 109 |
Level 2 [Member] | Warrants [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of liabilities |  |
Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of assets |  |
Level 3 [Member] | Marketable Equity Securities [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of assets |  |
Level 3 [Member] | Commodity Derivatives [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of assets |  |
Level 3 [Member] | Warrants [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Fair value of liabilities | $ 115 | $ 95

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + 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 (a) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Fair value of asset after deduction of liability. + References No definition available. + Details
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