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Summary Of Significant Accounting Policies [Line Items]

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Amount 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. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 45
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-Publisher FASB
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-Topic 946
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The amount of cash deposited in financial institutions as of the balance sheet date that is insured by the Federal Deposit Insurance Corporation.

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Amount of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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The cash inflow from disposal of asset without physical form usually arising from contractual or other legal rights, excluding goodwill.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
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Significant Accounting Policies - Additional Information (Details) $ in Thousands, $ in Thousands	1 Months Ended		3 Months Ended	9 Months Ended
	Aug. 31, 2020 USD ($)	May 31, 2016 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2021 CAD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2020 CAD ($)
Summary Of Significant Accounting Policies [Line Items]
Money market investments			$ 24,335	$ 24,335		$ 30,344
Cash			428	428	$ 37		$ 45
FDIC insured amount			250	$ 250
Percentage of royalties	5.00%			5.00%
Debt Securities, Unrealized Gain (Loss)			39	$ 137
Money Market Funds
Summary Of Significant Accounting Policies [Line Items]
Money market investments			$ 23,907	$ 23,907
Elion
Summary Of Significant Accounting Policies [Line Items]
Cash	$ 100
Eniluracil \| Elion
Summary Of Significant Accounting Policies [Line Items]
Cash proceeds from sale of Eniluracil		$ 40
Percentage of royalties		5.00%