Codexis, Inc. Annual report pursuant to Section 13 and 15(d)

Description of Business (Details) $ in Thousands	1 Months Ended				3 Months Ended	12 Months Ended
Description of Business (Details) $ in Thousands	Jun. 30, 2020 USD ($) shares	Mar. 31, 2020 USD ($) program	Feb. 28, 2019 USD ($)	Jul. 31, 2018 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Investment in non-marketable securities						$ 2,000	$ 0	$ 0
Nestec Ltd. (Nestle Health Sciences) \| CDX-6114
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue recognized			$ 3,000		$ 3,000
Nestec Ltd. (Nestle Health Sciences) \| CDX-6114 \| Collaborative Arrangement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Milestone payment amount			$ 1,000	$ 4,000
Takeda
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Number of initial programs \| program		3
Number of additional programs \| program		4
Collaboration payment		$ 8,500
Molecular Assemblies, Inc. \| Series A Preferred Stock
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Investment owned, balance (in shares) \| shares	1,587,050
Investment in non-marketable securities	$ 1,000