Subsequent Event	12 Months Ended
Dec. 31, 2020
Subsequent Events [Abstract]
Subsequent Event	Note 16. Subsequent Event In February 2021, the Company entered into a joint venture (“JV”) agreement with a company in China with the intent to develop, obtain regulatory approval for, manufacture and commercialize the INTERCEPT Blood System for platelets and red blood cells in China. Cerus and the Chinese company are the sole equity holders in the JV, with Cerus owning a majority (51%) of the entity. Cerus will contribute an exclusive license to commercialize the INTERCEPT Blood System for platelets and red blood cells for the JV to market in China.

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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