Development and License Agreements - Additional Information (Detail) € in Millions	1 Months Ended	3 Months Ended		6 Months Ended			12 Months Ended
	Aug. 31, 2019 EUR (€)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2020 EUR (€)	Jun. 30, 2019 USD ($)	Dec. 31, 2016 EUR (€)	Apr. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)
Licenses Agreements [Line Items]
Payments made relating to the manufacturing of the products		$ 6,300,000	$ 5,600,000	$ 14,400,000		$ 13,400,000
BARDA Agreement
Licenses Agreements [Line Items]
Additional committed fund receivable								$ 13,800,000
Committed fund receivable		116,900,000		116,900,000
Committed fund receivable		213,900,000		213,900,000
Accounts receivable of billed and unbilled amounts		$ 6,200,000		6,200,000					$ 4,200,000
Cerus Corporation | BARDA Agreement
Licenses Agreements [Line Items]
Co-investment by the company				5,000,000.0
Additional co-investment by the company				9,600,000
Co-investment incurred by the company				$ 1,500,000
Manufacturing and Supply Agreement | Fresenius
Licenses Agreements [Line Items]
Payments made based on the successful achievement of production volumes | €					€ 8.6
Manufacturing and development payments | €	€ 5.5						€ 3.1
Manufacturing and Supply Agreement | Fresenius | Measurement Input, Discount Rate
Licenses Agreements [Line Items]
Manufacturing and development obligations, discount rate							9.72