Promissory Notes - Promissory Notes Issued and Paid (Details) - USD ($)	12 Months Ended
Dec. 31, 2021	Mar. 31, 2022
Long-term Investments
Principal	$ 57,811,000	$ 57,788,000
YA II PN Note 1 \| Convertible Debt
Long-term Investments
Principal	37,500,000
Gross proceeds	$ 37,500,000
Interest rate	4.00%
Debt instrument, convertible, conversion price (in dollars per share)	$ 2.00
YA II PN Note 2 \| Convertible Debt
Long-term Investments
Principal	$ 37,500,000
Gross proceeds	$ 37,500,000
Interest rate	4.00%
Debt instrument, convertible, conversion price (in dollars per share)	$ 3.31
YA II PN Note 3 \| Convertible Debt
Long-term Investments
Principal	$ 65,000,000
Gross proceeds	$ 65,000,000
Interest rate	4.00%
Debt instrument, convertible, conversion price (in dollars per share)	$ 4.12
YA II PN Note 4 \| Convertible Debt
Long-term Investments
Principal	$ 80,000,000
Gross proceeds	$ 80,000,000
Interest rate	4.00%
Debt instrument, convertible, conversion price (in dollars per share)	$ 4.95

The price per share of the conversion feature embedded in the debt instrument.

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