Subsequent Event	3 Months Ended
Mar. 31, 2022
Subsequent Events [Abstract]
Subsequent Event	12. Subsequent Event In April 2022, the Company adopted the Kezar Life Sciences, Inc. 2022 Inducement Plan (the “Inducement Plan”), which is a non-stockholder approved stock plan adopted pursuant to the “inducement exception” provided under Nasdaq Listing Rule 5635(c)(4), for the award of nonstatutory stock options, restricted stock units and other equity awards as permitted by the Inducement Plan (collectively, “Inducement Awards”) to persons not previously an employee or director of the Company, or following a bona fide period of non-employment, as an inducement material to such persons entering into employment with the Company (“Eligible Recipients”). Under the Inducement Plan, the Company may grant up to 3,000,000 shares of Common Stock in the form of Inducement Awards to Eligible Recipients in compliance with the requirements of Nasdaq Listing Rule 5635(c)(4).

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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