Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of writeoff of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair Value Measurements (Details) - USD ($)	12 Months Ended
Fair Value Measurements (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Nov. 30, 2020
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Non-marketable debt security	$ 0	$ 1,000,000	$ 1,000,000
Total		128,567,000
Convertible Debt
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Non-marketable debt security	0
Other-than-temporary impairment losses	0	0
Credit losses	0	0
Money market funds
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Money market funds	86,095,000	127,567,000
Level 1
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Total		127,567,000
Level 1 \| Money market funds
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Money market funds	$ 86,095,000	127,567,000
Level 3
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Non-marketable debt security		1,000,000
Total		$ 1,000,000