XOMA Corporation Annual report pursuant to Section 13 and 15(d)

Royalty and Commercial Payment Purchase Agreements - Bioasis (Details)			12 Months Ended
	Nov. 02, 2020 USD ($)	Feb. 25, 2019 USD ($) agreement	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Agreements
Long-term royalty and commercial payment receivables			$ 63,683,000	$ 69,075,000	$ 34,575,000
Contingent consideration under RPAs and CPPAs			75,000	8,075,000
Impairment of long-term royalty receivable			0	$ 0
Bioasis \| Royalty Purchase Agreement
Agreements
Percentage of option to purchase royalty right on future license agreements		1.00%
Number of future license agreements under optional purchase right \| agreement		2
Obligation upon exercise of options per licensed product, second agreement		$ 300,000
Obligation upon exercise of options per licensed product, third agreement		400,000
Payments related to purchase of royalty rights and other commercial payment rights		300,000
Long-term royalty and commercial payment receivables		400,000
Contingent consideration under RPAs and CPPAs		100,000	100,000
Changes in estimated fair value of contingent consideration			0
Payments of contingent consideration			0
Impairment of long-term royalty receivable			0
Bioasis \| Royalty Purchase Agreement \| Maximum
Agreements
Potential future cash payments		$ 200,000
Bioasis \| Second Royalty Purchase Agreement
Agreements
Payments related to purchase of royalty rights and other commercial payment rights	$ 1,200,000
Long-term royalty and commercial payment receivables	$ 1,200,000
Impairment of long-term royalty receivable			$ 0