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

Annual report pursuant to Section 13 and 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Basis of Presentation and Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Long-Term Debt and Other Financings - Hercules Term Loan - Additional Information (Details)

v3.8.0.1

Long-Term Debt and Other Financings - Hercules Term Loan - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended		12 Months Ended
	Feb. 27, 2015	Jan. 31, 2017	Feb. 29, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Repayment of principal				$ 16,380	$ 6,890	$ 6,128
Loss on extinguishment of debt				$ (650)		(429)
Aggregate number of unregistered shares of common stock called by warrants (in shares)			8,249
Exercise price of warrants (in dollars per share)			$ 15.40
Fair value of warrants			$ 100
Exercisable period of warrants			5 years
Hercules Term Loan [Member]
Debt Instrument [Line Items]
Maturity date	Sep. 01, 2018
Variable rate basis				The Hercules Term Loan had a variable interest rate that is the greater of either (i) 9.40% plus the prime rate as reported from time to time in The Wall Street Journal minus 7.25%, or (ii) 9.40%.
Period of principal and interest amortized	30 months
Amortization of interest payments period end date	Jun. 01, 2016
Period of interest	1 month
Additional interest rate in case of default	5.00%
Debt issuance costs	$ 500
Final payment fee	$ 1,200
Amortization of debt discount				$ 200	700	$ 500
Outstanding principal balance					17,500
Carrying value of the loan					$ 16,900
Repayment of principal		$ 10,000
Prepayment charge not required to pay				1.00%
Loss on extinguishment of debt				$ 500
Aggregate number of unregistered shares of common stock called by warrants (in shares)	9,063
Exercise price of warrants (in dollars per share)	$ 66.20
Fair value of warrants	$ 500
Exercisable period of warrants	5 years
Warrants expiration period	2020-02
Minimum [Member] \| Hercules Term Loan [Member]
Debt Instrument [Line Items]
Percentage bearing variable rate				9.40%
Prime Rate [Member] \| Hercules Term Loan [Member]
Debt Instrument [Line Items]
Basis spread, addition				9.40%
Basis spread, subtraction				7.25%

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Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Fair value portion of warrants not settleable in cash classified as equity.

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Represents additional interest rate in case of default.

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Amortization of interest payments period end date.

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The month and year (YYYY-MM) in which the warrants or rights expire.

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Represents the exercisable period for warrants beginning on the date of issuance and ending on the earlier to occurrence.

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The amount of final payment fee due on maturity of the loan.

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Percentage of prepayment charge on debt.

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Represents the period of interest prior to the amortization date.

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Represents period of principal and interest amortization.

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Reduction of percentage of interest under loan agreement.

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