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Available-for-Sale Securities - Information on Securities (Details)	Jan. 28, 2021 USD ($)	Sep. 30, 2022 USD ($)	Jun. 01, 2022	Dec. 31, 2021 USD ($)
Debt Securities, Available-for-Sale [Line Items]
Cost		$ 15,000,000
Interest		902,000
Unrealized Gains		4,000
Unrealized Losses		(20,000)
Impairment		(15,886,000)
Estimated Fair Value		0
Principal Amount		13,233,000		$ 57,811,000
Silk EV Note \| Convertible Debt
Debt Securities, Available-for-Sale [Line Items]
Principal Amount	$ 15,000,000
Interest rate	6.00%		6.00%
Conversion ratio (as a percent)	0.80
Silk EV \| Convertible promissory note and interest
Debt Securities, Available-for-Sale [Line Items]
Cost		15,000,000
Interest		902,000
Unrealized Gains		4,000
Unrealized Losses		(20,000)
Impairment		(15,886,000)		$ (15,800,000)
Estimated Fair Value	$ 15,000,000	$ 0