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

Compensation and Other Benefit Plans - Stock Option Plans (Details)

v3.20.4

Compensation and Other Benefit Plans - Stock Option Plans (Details) - shares	1 Months Ended			12 Months Ended
	May 31, 2019	May 31, 2017	May 31, 2016	Dec. 31, 2020	Dec. 31, 2019
Share-based compensation
Number of options outstanding				1,827,906	1,839,623
2010 Plan \| Minimum \| Terminated employee
Share-based compensation
Expiration period				3 months
2010 Plan \| Maximum
Share-based compensation
Expiration period				10 years
2010 Plan \| Maximum \| Terminated employee
Share-based compensation
Expiration period				6 months
2010 Plan \| Options and Stock Appreciation Rights
Share-based compensation
Maximum shares per employee		2,000,000
2010 Plan \| Other Types of Stock Awards
Share-based compensation
Maximum shares per employee		2,000,000
2010 Plan \| Stock Options
Share-based compensation
Shares available for grant				321,716
2010 Plan \| Common Stock
Share-based compensation
Increase in aggregate number of shares authorized for issuance	450,000	1,470,502	170,000
Shares authorized for issuance	3,029,062	2,579,062	1,108,560
2010 Plan \| Common Stock \| Stock Options
Share-based compensation
Increase in aggregate number of shares authorized for issuance	450,000	2,004,087
Shares authorized for issuance	3,029,062	2,579,062

- Definition

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- Definition

The highest quantity of shares an employee can purchase under the plan per period.

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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

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Number of shares authorized for issuance under share-based payment arrangement.

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-Publisher FASB
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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of options outstanding, including both vested and non-vested options.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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