XOMA Corporation Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation and Significant Accounting Policies - Concentration of Risk (Details)

v3.23.3

Basis of Presentation and Significant Accounting Policies - Concentration of Risk (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023 customer	Sep. 30, 2022 customer	Sep. 30, 2023 customer	Sep. 30, 2022 customer	Dec. 31, 2022 USD ($)
Concentration of Risk
Trade receivable, net \| $					$ 0.0
Customer Concentration Risk \| Revenues
Concentration of Risk
Number of major partners	2	1	2	4
Customer Concentration Risk \| Revenues \| Partner 1
Concentration of Risk
Concentration risk (as a percent)	73.00%	94.00%	54.00%	44.00%
Customer Concentration Risk \| Revenues \| Partner 2
Concentration of Risk
Concentration risk (as a percent)	24.00%		44.00%	27.00%
Customer Concentration Risk \| Revenues \| Partner 3
Concentration of Risk
Concentration risk (as a percent)				17.00%
Customer Concentration Risk \| Revenues \| Two partners
Concentration of Risk
Concentration risk (as a percent)				11.00%
Credit Concentration Risk \| Trade Receivables \| Partner 1
Concentration of Risk
Number of major partners			1
Concentration risk (as a percent)			100.00%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
-SubTopic 310
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481027/954-310-50-2

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-42

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- Definition

Amount to be collected within one year of the balance sheet date (or one operating cycle, if longer) from customers in accordance with the contractual provisions of long-term contracts or programs including amounts billed and unbilled as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3)(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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- Definition

Number of major partners.

+ References

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