Commitment and Contingencies (Details) $ in Millions, € in Billions			12 Months Ended			22 Months Ended
	Dec. 23, 2024 lawsuit	Feb. 15, 2023 plaintiff officer_and_director	Apr. 30, 2025 USD ($)	Apr. 30, 2024 USD ($)	Apr. 30, 2023 USD ($)	Mar. 26, 2024 claim	Feb. 27, 2024 EUR (€)
Long-term Purchase Commitment [Line Items]
Purchase commitment, incurred cost			$ 117.1	$ 43.1	$ 8.3
The Reckstin Family Trust v. C3.ai, Inc. | Settled Litigation
Long-term Purchase Commitment [Line Items]
Number of additional plaintiffs | plaintiff		3
Number of current and former officers and directors | officer_and_director		4
Suri V. Siebel Et Al., Rabasca V. Siebel Et Al., Vo V. Siebel Et Al, Lanfair V. Siebel Et Al. And Pankow V. Siebel Et Al. | Pending Litigation
Long-term Purchase Commitment [Line Items]
Number of actions filed | claim						6
Enel | Pending Litigation
Long-term Purchase Commitment [Line Items]
Number of actions filed | lawsuit	2
Gain contingency, compensatory damages sought | €							€ 2.1
Number of patents allegedly infringed | lawsuit	2
C3.ai DTI Grants Program
Long-term Purchase Commitment [Line Items]
Grants, potential remaining contributions				$ 31.6
Cloud Hosting Services
Long-term Purchase Commitment [Line Items]
Remaining amount committed			427.5
Professional services
Long-term Purchase Commitment [Line Items]
Remaining amount committed			$ 111.5
Professional services | Minimum
Long-term Purchase Commitment [Line Items]
Purchase commitment, term (in years)			1 year
Professional services | Maximum
Long-term Purchase Commitment [Line Items]
Purchase commitment, term (in years)			5 years