| Document And Entity Information | Aug. 01, 2024 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Aug. 01, 2024 |
| Entity Registrant Name | CERUS CORPORATION |
| Entity Central Index Key | 0001020214 |
| Entity Emerging Growth Company | false |
| Entity File Number | 000-21937 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 68-0262011 |
| Entity Address, Address Line One | 1220 Concord Avenue, Suite 600 |
| Entity Address, City or Town | Concord |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 94520 |
| City Area Code | 925 |
| Local Phone Number | 288-6000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, par value $0.001 per share |
| Trading Symbol | CERS |
| Security Exchange Name | NASDAQ |
