Redeemable Noncontrolling Interest - Changes in Redeemable Noncontrolling Interest (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Redeemable Noncontrolling Interest
Balance at beginning of period	$ 22,164	$ 20,878	$ 22,033	$ 20,670
Cash contribution by Wuxi LP	0	0	0	0
Share of CASI Wuxi net loss	(317)	(166)	(666)	(275)
Accretion to redeemable non-controlling interest redemption value	519	362	1,067	679
Foreign currency translation adjustment	331		263
Balance at end of period	$ 22,697	$ 21,074	$ 22,697	$ 21,074

Amount of Accretion of Redeemable Non Controlling Interest.

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- Definition

Adjustments to noncontrolling interests which are redeemable by the (parent) entity foreign currency translation adjustments.

+ References

No definition available.

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- Definition

Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.19)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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- References

No definition available.

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- Definition

Amount of cash inflow from a noncontrolling interest. Includes, but is not limited to, purchase of additional shares or other increase in noncontrolling interest ownership.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

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- Definition

As of the reporting date, the carrying amount of noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. The noncontrolling interest holder's ownership (or holders' ownership) may be in the form of common shares (regardless of class), limited partnership units (regardless of class), non-preferential membership interests, or any other form of common equity regardless of investee entity legal form.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph (16)(c)
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764

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