Fair Value Measurements - Financial and Non-Financial Assets and Liabilities (Details) - USD ($)	6 Months Ended	12 Months Ended
Jun. 30, 2021	Dec. 31, 2020
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investment in common stock	$ 12,588,000	$ 9,309,000
Investment in warrants -Designated as investment measured at FVTPL	996,000	840,000
Investment in convertible loan-AFS	169,000	83,000
Investment in convertible loan-Designated as investment measured at FVTPL	5,547,000
Level 1 \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investment in common stock	12,588,000	9,309,000
Investment in warrants -Designated as investment measured at FVTPL	0
Investment in convertible loan-AFS	0	0
Investment in convertible loan-Designated as investment measured at FVTPL	0
Level 2 \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investment in common stock	0	0
Investment in warrants -Designated as investment measured at FVTPL	996,000	840,000
Investment in convertible loan-AFS	0	0
Investment in convertible loan-Designated as investment measured at FVTPL	0
Level 3 \| Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investment in common stock	0	0
Investment in convertible loan-AFS	169,000	$ 83,000
Investment in convertible loan-Designated as investment measured at FVTPL	5,547,000
Black Belt Tx Limited \| Non-recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investment in equity securities using measurement alternative, fair value	$ 1,385,000

Amount of Investments fair value disclosure convertible loan.

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Amount of Investments fair value disclosure convertible loan measured at fair value through profit and loss.

+ References

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- Definition

Amount of Investments fair value disclosure warrants measured at fair value through profit and loss.

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- Definition

Amount of investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117539-209714

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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.

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ 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 (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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