Balance Sheet Account Detail - Summary of Cash and Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands, shares in Millions	9 Months Ended
Sep. 30, 2022	Dec. 31, 2021
Schedule of Investments [Line Items]
Equity securities, historical or amortized cost	$ 0	$ 3,512
Total cash and cash equivalents and marketable securities, historical or amortized cost	98,603	97,269
Equity securities	258	5,718
Total cash and cash equivalents and marketable securities	$ 100,252	100,647
CASI Common Stock
Schedule of Investments [Line Items]
Number of common shares sale in investments (in shares)	0.9
Realized loss from sale of equity securities	$ (1,900)
Unicycive Therapeutics, Inc.
Schedule of Investments [Line Items]
Equity securities	$ 300
Number of shares held in investment (in shares)	0.4
Number of common shares sale in investments (in shares)	0.4
Realized gain from sale of equity securities	$ 400
Cash and Cash Equivalents
Schedule of Investments [Line Items]
Equity securities	0	0
Total cash and cash equivalents and marketable securities	56,255	88,539
Marketable Securities
Schedule of Investments [Line Items]
Equity securities	258	5,718
Total cash and cash equivalents and marketable securities	43,997	12,108
Money market funds
Schedule of Investments [Line Items]
Available-for-sale, historical or amortized cost	40,913	66,322
Available-for-sale	40,913	66,322
Money market funds \| Cash and Cash Equivalents
Schedule of Investments [Line Items]
Available-for-sale	40,913	66,322
Money market funds \| Marketable Securities
Schedule of Investments [Line Items]
Available-for-sale	0	0
Government-related debt securities
Schedule of Investments [Line Items]
Available-for-sale, historical or amortized cost	45,172
Available-for-sale	45,158
Government-related debt securities \| Cash and Cash Equivalents
Schedule of Investments [Line Items]
Available-for-sale	4,970
Government-related debt securities \| Marketable Securities
Schedule of Investments [Line Items]
Available-for-sale	40,188
Mutual funds
Schedule of Investments [Line Items]
Available-for-sale, historical or amortized cost	2,146	5,218
Available-for-sale	3,551	6,390
Mutual funds \| Cash and Cash Equivalents
Schedule of Investments [Line Items]
Available-for-sale	0	0
Mutual funds \| Marketable Securities
Schedule of Investments [Line Items]
Available-for-sale	3,551	6,390
Bank deposits
Schedule of Investments [Line Items]
Available-for-sale, historical or amortized cost	10,372	22,217
Available-for-sale	10,372	22,217
Bank deposits \| Cash and Cash Equivalents
Schedule of Investments [Line Items]
Available-for-sale	10,372	22,217
Bank deposits \| Marketable Securities
Schedule of Investments [Line Items]
Available-for-sale	$ 0	$ 0

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Amortized cost 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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Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means 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. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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Amount of realized gain from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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