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

Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation (Details)

Stock-based Compensation (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 2,122	$ 1,542	$ 3,368	$ 5,598
Research and Development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	1,304	458	1,984	2,404
Selling, General and Administrative Expenses [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	818	1,084	1,384	3,194
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance (in shares)	2,161,920		2,161,920
Stock-based awards weighted average assumptions [Abstract]
Dividend yield (in hundredths)	0.00%	0.00%	0.00%	0.00%
Expected volatility (in hundredths)	92.00%	89.00%	92.00%	87.00%
Risk free interest rate (in hundredths)	0.65%	0.96%	0.83%	1.86%
Expected term	5 years 7 months 6 days	5 years 7 months 6 days	5 years 7 months 6 days	5 years 3 months 18 days
Stock option activity [Roll Forward]
Options outstanding beginning of period (in shares)			5,053,435
Granted (in shares)			2,161,920
Exercised (in shares)			(77,797)
Forfeited, expired or cancelled (in shares)			(484,144)
Options outstanding end of period (in shares)	6,653,414		6,653,414
Options exercisable at end period (in shares)	4,003,868		4,003,868
Stock options activity, weighted average exercise price [Roll Forward]
Options outstanding, beginning of period (in dollars per share)			$ 12.55
Granted (in dollars per share)			$ 2.57
Exercised (in dollars per share)			$ 1.69
Forfeited, expired or cancelled (in dollars per share)			$ 15.96
Options outstanding, end of period (in dollars per share)	$ 9.19		$ 9.19
Options exercisable weighted average exercise price (in dollars per share)	$ 13.10		$ 13.10
Additional Disclosures [Abstract]
Options outstanding weighted average remaining contractual term beginning of period			6 years 10 months 20 days
Options outstanding weighted average remaining contractual term end of period			6 years 10 months 20 days
Options exercisable weighted average remaining contractual term			6 years 6 months 11 days
Options outstanding, aggregate intrinsic value at beginning of period			0
Options outstanding, aggregate intrinsic value at end of period	4,520,629		4,520,629
Options exercisable, aggregate intrinsic value	$ 2,106,931		$ 2,106,931
Stock Options [Member] \| Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			1 year
Stock Options [Member] \| Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			4 years
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance (in shares)	1,190,323		1,190,323
Vesting period			3 years
Unvested RSU activity [Roll Forward]
Unvested balance beginning of period (in shares)			903,874
Granted (in shares)			1,190,323
Vested (in shares)			(194,629)
Forfeited (in shares)			(200,261)
Unvested balance end of period (in shares)	1,699,307		1,699,307
Share-based , nonvested, weighted average grant date fair value [Roll Forward]
Unvested balance beginning of period (in dollars per share)			$ 1.69
Granted (in dollars per share)			$ 2.84
Vested (in dollars per share)			$ 3.44
Forfeited (in dollars per share)			$ 1.69
Unvested balance end of period (in dollars per share)	$ 2.29		$ 2.29