Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Income Tax Disclosure [Line Items]
Income tax expense	$ 66	$ 85	$ 252	$ 235
Cerus Europe B.V.
Income Tax Disclosure [Line Items]
Income tax expense	$ 100	$ 100	$ 300	$ 200

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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+ Details