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).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

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- Definition

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.

+ References

No definition available.

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 9
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455

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- References

No definition available.

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Fair Value Measurements (Details) - USD ($)	3 Months Ended
Fair Value Measurements (Details) - USD ($)	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Convertible Debt
Summary of financial instruments measured at fair value on a recurring basis
Credit losses	$ 0	$ 0
Other-than-temporary impairment losses	0	$ 0
Money market funds
Summary of financial instruments measured at fair value on a recurring basis
Money market funds	72,107,000		$ 86,095,000
Level 1 \| Money market funds
Summary of financial instruments measured at fair value on a recurring basis
Money market funds	72,107,000		86,095,000
Level 2 \| Money market funds
Summary of financial instruments measured at fair value on a recurring basis
Money market funds	0		0
Level 3 \| Money market funds
Summary of financial instruments measured at fair value on a recurring basis
Money market funds	$ 0		$ 0