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
	Jan. 09, 2015 USD ($) Tranche	Jan. 31, 2017 USD ($)	Jan. 31, 2016 EUR (€)	Jan. 31, 2011 USD ($)	Jun. 30, 2017 USD ($) € / $	Jun. 30, 2016 USD ($)	Jul. 31, 2017	Jun. 30, 2017 USD ($) € / $	Jan. 31, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 EUR (€) € / $	Jan. 31, 2017 EUR (€)	Dec. 31, 2016 USD ($) € / $	Jan. 09, 2015 EUR (€) Tranche
Debt Instrument [Line Items]
Accrued interest paid								$ 396,000		$ 1,127,000
Carrying value of the loan					$ 27,861,000			$ 27,861,000
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
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
Accrued interest paid \| €			€ 200,000
Unamortized discount on debt	$ 1,900,000			$ 8,900,000
Amortization of debt discount					100,000	$ 200,000		$ 200,000		300,000
Carrying value of the loan					13,500,000			13,500,000					$ 12,200,000
Unrealized foreign exchange gains (loss) related to re-measurement of loan discount					14,000	(17,000)		20,000		20,000
Outstanding principal balance					$ 13,700,000			$ 13,700,000					$ 12,600,000
Euro to US Dollar exchange rates \| € / $					1.142			1.142			1.142		1.052
Unrealized foreign exchange gains (loss) related to re-measurement of loan					$ (900,000)	$ 300,000		$ (1,100,000)		$ (200,000)
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] \| Mid-July 2016 Through Mid-January 2017 [Member]
Debt Instrument [Line Items]
Period of interest resetting									6 months
Interest rate during period									1.81%
Servier Loan [Member] \| Amendment No.3 [Member] \| Tranche Two [Member]
Debt Instrument [Line Items]
Maturity date		Jul. 15, 2017
Principal payment amount \| €												€ 5,000,000
Unamortized discount on debt		$ 400,000							$ 400,000
Servier Loan [Member] \| Forecast [Member] \| Mid-January 2017 Through Mid-July 2017 [Member]
Debt Instrument [Line Items]
Period of interest resetting							6 months
Interest rate during period							1.77%