Subsequent Event	9 Months Ended
Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Event	12. Subsequent Event In October 2021, we entered into a lease amendment to reduce the amount of laboratory and office space in San Diego, California and we entered into a sublease agreement to sublet laboratory and office space in San Diego, California (see Note 7). In October 2021, we implemented a restructuring plan under which we provided or will provide employees one-time severance payments upon termination, continued benefits for a specific period of time, outplacement services and certain stock option modifications. We expect to incur total expenses of $1.6 million, $1.5 million of which is primarily for severance and $0.1 million of which is for non-cash, stock-based compensation expense related to stock option modifications. We expect that the cash payments due under this restructuring will be substantially completed in the fourth quarter of 2021.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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