The amount of aggregate consideration for equity investment.

No definition available.

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Total number of installments in which the consideration for equity method investment will be paid.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting obtained during the period.

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Represents the percentage of equity held in joint venture.

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Represents percentage of interest in board seats.

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Amount of other-than-temporary decline in value that has been recognized against investment accounted for under equity method of accounting.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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INVESTMENT IN EQUITY SECURITIES, AT FAIR VALUE AND LONG-TERM INVESTMENTS - Investment in Precision Autoimmune Therapeutics Co Ltd (PAT) (Details) ¥ in Millions	1 Months Ended									12 Months Ended
	Mar. 31, 2026 USD ($)	Mar. 31, 2026 CNY (¥)	Jan. 31, 2026 USD ($)	Jan. 31, 2026 CNY (¥)	Apr. 30, 2025 USD ($) installment	Apr. 30, 2025 CNY (¥)	Aug. 31, 2024 USD ($)	Aug. 31, 2024 CNY (¥)	May 31, 2022 USD ($)	Dec. 31, 2025 USD ($) installment	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2025 CNY (¥) installment	Apr. 30, 2025 CNY (¥) installment	Jul. 31, 2024 USD ($) installment	Jul. 31, 2024 CNY (¥) installment	May 31, 2022 CNY (¥)
Schedule of Investments
Share of net loss of an equity investee										$ 2,187,000	$ 1,189,000	$ 48,000
Payments to acquire equity investments										$ 1,624,000	1,370,000
Precision Autoimmune Therapeutics Co., Ltd
Schedule of Investments
Equity ownership (as a percent)										19.8876%				19.8876%
Aggregate consideration for equity investment									$ 3,000,000	$ 8,100,000				¥ 56.8				¥ 20.0
Share of net loss of an equity investee												48,000	$ 800,000
Number of installments \| installment										5				5
Impairment of equity investment												$ 2,000,000
Payments to acquire equity investments							$ 5,100,000	¥ 35.4
Precision Autoimmune Therapeutics Co., Ltd \| Agreement one
Schedule of Investments
Share of net loss of an equity investee										$ 2,200,000	$ 1,200,000
Number of installments \| installment																3	3
CASI China \| Precision Autoimmune Therapeutics Co., Ltd
Schedule of Investments
Aggregate consideration for equity investment \| ¥															¥ 28.4
Percentage of equity held in joint venture									15.00%
Percentage of interest in board seats									33.33%
CASI China \| Precision Autoimmune Therapeutics Co., Ltd \| Agreement one
Schedule of Investments
Equity ownership (as a percent)																19.8876%	19.8876%
Aggregate consideration for equity investment																$ 4,100,000	¥ 28.4
Payments to acquire equity investments					$ 1,400,000	¥ 10.0	$ 1,400,000	¥ 10.0
Equity method investment, ownership percentage					10.04%		5.17%	5.17%							10.04%
CASI China \| Precision Autoimmune Therapeutics Co., Ltd \| Agreement Two
Schedule of Investments
Equity ownership (as a percent)					19.8876%										19.8876%
Aggregate consideration for equity investment					$ 4,100,000										¥ 28.4
Number of installments \| installment					2										2
CASI China \| Precision Autoimmune Therapeutics Co., Ltd \| Subsequent event \| Agreement one
Schedule of Investments
Payments to acquire equity investments	$ 1,200,000	¥ 8.4
CASI China \| Precision Autoimmune Therapeutics Co., Ltd \| Subsequent event \| Agreement Two
Schedule of Investments
Payments to acquire equity investments			$ 1,000,000	¥ 7.0