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

Quarterly report pursuant to Section 13 or 15(d)

Long-Term Debt - Servier Loan Agreement - Additional Information (Details)

Long-Term Debt - Servier Loan Agreement - Additional Information (Details)		1 Months Ended		3 Months Ended		6 Months Ended				9 Months Ended
	Jan. 09, 2015 USD ($) Tranche	Jan. 31, 2016 EUR (€)	Jan. 31, 2011 USD ($)	Sep. 30, 2016 USD ($) € / $	Sep. 30, 2015 USD ($)	Jan. 31, 2017	Jul. 31, 2016	Jan. 31, 2016 EUR (€)	Jul. 31, 2011	Sep. 30, 2016 USD ($) € / $	Sep. 30, 2015 USD ($)	Sep. 30, 2016 EUR (€) € / $	Dec. 31, 2015 USD ($) € / $	Jan. 09, 2015 EUR (€) Tranche
Debt Instrument [Line Items]
Accrued interest paid										$ 1,724,000	$ 1,452,000
Carrying value of the loan				$ 45,219,000						$ 45,219,000			$ 48,667,000
Servier Loan [Member]
Debt Instrument [Line Items]
Date of agreement										Dec. 30, 2010
Maximum borrowing capacity under loan agreement \| €												€ 15,000,000
Proceeds from loan			$ 19,500,000
Interest rate during period									3.22%
Date of loan amendment										Jan. 09, 2015
Date of agreement, after amendment										Aug. 12, 2013
Number of tranches \| Tranche	3													3
Principal payment amount \| €		€ 3,000,000						€ 3,000,000
Accrued interest paid \| €		€ 200,000
Unamortized discount on debt	$ 1,900,000		$ 8,900,000
Amortization of debt discount				200,000	$ 200,000					$ 500,000	500,000
Carrying value of the loan				12,900,000						12,900,000			15,300,000
Unrealized foreign exchange gains (loss) related to re-measurement of loan discount				6,000	17,000					$ 26,000	(200,000)
Agreement termination date										Sep. 28, 2015
Agreement termination notice period										180 days
Outstanding principal balance				$ 13,500,000						$ 13,500,000			$ 16,400,000
Euro to US Dollar exchange rates \| € / $				1.121						1.121		1.121	1.091
Unrealized foreign exchange gains (loss) related to re-measurement of loan				$ (100,000)	$ (200,000)					$ (400,000)	$ 1,400,000
Servier Loan [Member] \| Tranche One [Member]
Debt Instrument [Line Items]
Maturity date	Jan. 15, 2016
Principal payment amount \| €														€ 3,000,000
Servier Loan [Member] \| Tranche Two [Member]
Debt Instrument [Line Items]
Maturity date	Jan. 15, 2017
Principal payment amount \| €														5,000,000
Servier Loan [Member] \| Tranche Three [Member]
Debt Instrument [Line Items]
Maturity date	Jan. 15, 2018
Principal payment amount \| €														€ 7,000,000
Servier Loan [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Interest rates reset semi-annually				1.81%						1.81%		1.81%
Servier Loan [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Interest rates reset semi-annually				3.83%						3.83%		3.83%
Servier Loan [Member] \| Mid-July 2015 Through Mid-January 2016 [Member]
Debt Instrument [Line Items]
Interest rate during period								2.05%
Period of interest resetting								6 months
Servier Loan [Member] \| Mid-January 2016 Through Mid-July 2016 [Member]
Debt Instrument [Line Items]
Interest rate during period							1.95%
Period of interest resetting							6 months
Servier Loan [Member] \| Scenario, Forecast [Member] \| Mid-July 2016 Through Mid-January 2017 [Member]
Debt Instrument [Line Items]
Interest rate during period						1.81%
Period of interest resetting						6 months