CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Statement of Comprehensive Income [Abstract]
Net loss	$ (5,715)	$ (5,775)	$ (13,433)	$ (15,465)
Other comprehensive loss
Foreign currency translation gain (loss) adjustment	5	(3)	8	(11)
Unrealized (losses) gains on available-for-sale investments, net of taxes	(12)	258	119	418
Comprehensive loss	(5,722)	(5,520)	(13,306)	(15,058)
Comprehensive loss attributable to noncontrolling interest	(8)	(0)	(9)	(2)
Total comprehensive loss attributable to Cerus Corporation	$ (5,714)	$ (5,520)	$ (13,297)	$ (15,056)