Summary of Significant Accounting Policies - Additional Information (Detail)	1 Months Ended	12 Months Ended
	Feb. 28, 2021	Dec. 31, 2022 USD ($) Segment Customer	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Net cash used in operating activities		$ (25,615,000)	$ (33,922,000)	$ (41,811,000)
Description of payment of customer invoice contract		The Company invoices its customers based upon the terms in the contracts, which generally require payment 30 to 60 days from the date of invoice.
Application of an optional exemption not to disclose the value of unsatisfied performance obligations		true
Number of major customers representing outstanding trade receivables | Customer		2
Inventory valuation reserves		$ 700,000
Non-cash purchases of capital expenditures		$ 700,000	100,000
Number of reportable segments | Segment		1
Operating expenses		$ 147,442,000	144,979,000	131,425,000
Dispose, impair or recognition of additional goodwill		0	0	0
Impairment on investments			0
Impairments for long-lived assets		$ 0	0	300,000
Period of warranty		1 year
Warranty claim liability		$ 0	0
Cerus Zhongbaokang Shandong Biomedical Co L T D
Summary Of Significant Accounting Policies [Line Items]
Operating expenses		$ 200,000
China | Cerus Zhongbaokang Shandong Biomedical Co L T D
Summary Of Significant Accounting Policies [Line Items]
Variable interest entity, Purpose of VIE		the Company entered into an Equity Joint Venture Contract with Shandong Zhongbaokang Medical Implements Co., Ltd. (“ZBK”), to establish Cerus Zhongbaokang (Shandong) Biomedical Co., LTD. (the “JV”) for the purpose of developing, obtaining regulatory approval for, and eventual manufacturing and commercialization of the INTERCEPT blood transfusion for platelets and red blood cells in the People’s Republic of China.
Ownership percentage	51.00%
Noncontrolling interest in variable interest entity			$ 1,000,000.0
Trade Accounts Receivable | Customer Concentration Risk | Customers
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage		49.00%	48.00%
Other Assets
Summary Of Significant Accounting Policies [Line Items]
Cash surrender value of associated life insurance policies		$ 1,900,000	$ 1,100,000
Other Non-current Liabilities
Summary Of Significant Accounting Policies [Line Items]
Liability for deferred compensation		$ 1,900,000	1,200,000
Minimum
Summary Of Significant Accounting Policies [Line Items]
Payment of customer invoice contract period		30 days
Estimated useful life of property and equipment		3 years
Maximum
Summary Of Significant Accounting Policies [Line Items]
Payment of customer invoice contract period		60 days
Percentage of deferred compensation from base salary		80.00%
Percentage of deferred compensation from variable compensation		100.00%
Shelf lives of inventory		24 months
Inventory valuation reserves			200,000
Estimated useful life of property and equipment		5 years
Product
Summary Of Significant Accounting Policies [Line Items]
Contract asset		$ 100,000	$ 0
Preferred Stock and Warrants
Summary Of Significant Accounting Policies [Line Items]
Impairment on investments		$ 2,200,000
Immaterial Correction of an Error
Summary Of Significant Accounting Policies [Line Items]
Net cash used in operating activities				$ 1,100,000