Balance Sheet Account Detail - Summary of Cash and Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands, shares in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Schedule of Investments [Line Items]
Historical or Amortized Cost	$ 3,512	$ 3,764
Historical or Amortized Cost	97,269	157,712
Equity securities	5,718	24,946
Cash, cash equivalents, and short-term investments	100,647	180,025
Level 1
Schedule of Investments [Line Items]
Equity securities	$ 5,718	24,946
CASI Common Stock
Schedule of Investments [Line Items]
Number of shares held in investment (in shares)	5.1
Number of common shares sale in investments (in shares)	3.4
Realized gain on equity securities	$ 5,700
CASI Common Stock \| Level 1
Schedule of Investments [Line Items]
Equity securities	4,000
Unicycive Therapeutics, Inc.
Schedule of Investments [Line Items]
Equity securities	$ 1,700
Number of shares held in investment (in shares)	0.8
Cash and Cash Equivalents
Schedule of Investments [Line Items]
Equity securities	$ 0	0
Cash, cash equivalents, and short-term investments	88,539	46,009
Marketable Securities
Schedule of Investments [Line Items]
Equity securities	5,718	24,946
Cash, cash equivalents, and short-term investments	12,108	134,016
Money market funds
Schedule of Investments [Line Items]
Historical or Amortized Cost	66,322	40,560
Available-for-sale	66,322	40,560
Money market funds \| Cash and Cash Equivalents
Schedule of Investments [Line Items]
Available-for-sale	66,322	40,560
Money market funds \| Marketable Securities
Schedule of Investments [Line Items]
Available-for-sale	0	0
Government-related debt securities
Schedule of Investments [Line Items]
Historical or Amortized Cost		92,881
Available-for-sale		92,928
Government-related debt securities \| Cash and Cash Equivalents
Schedule of Investments [Line Items]
Available-for-sale		0
Government-related debt securities \| Marketable Securities
Schedule of Investments [Line Items]
Available-for-sale		92,928
Corporate debt securities
Schedule of Investments [Line Items]
Historical or Amortized Cost		8,846
Available-for-sale		8,848
Corporate debt securities \| Cash and Cash Equivalents
Schedule of Investments [Line Items]
Available-for-sale		0
Corporate debt securities \| Marketable Securities
Schedule of Investments [Line Items]
Available-for-sale		8,848
Mutual funds
Schedule of Investments [Line Items]
Historical or Amortized Cost	5,218	4,497
Available-for-sale	6,390	5,573
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	6,390	5,573
Bank CDs
Schedule of Investments [Line Items]
Historical or Amortized Cost		1,715
Available-for-sale		1,721
Bank CDs \| Cash and Cash Equivalents
Schedule of Investments [Line Items]
Available-for-sale		0
Bank CDs \| Marketable Securities
Schedule of Investments [Line Items]
Available-for-sale		1,721
Bank deposits
Schedule of Investments [Line Items]
Historical or Amortized Cost	22,217	5,449
Available-for-sale	22,217	5,449
Bank deposits \| Cash and Cash Equivalents
Schedule of Investments [Line Items]
Available-for-sale	22,217	5,449
Bank deposits \| Marketable Securities
Schedule of Investments [Line Items]
Available-for-sale	$ 0	$ 0

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