Share-based Payment - Summary of Weighted Average Fair Value of Programs Granted and Principal Assumptions used in Applying Black-Scholes Model (Detail) - R$ / shares	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Cosan S.A. Industria e Comercio [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share price at grant date	R$ 23.2	R$ 83.73
Risk-free interest rate	6.82%	6.94%
Volatility factor	36.50%	36.50%
Rumo S.A. [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share price at grant date	R$ 18.2	R$ 20.01
Risk-free interest rate	6.94%	6.94%
Volatility factor	26.51%	36.50%
Comgas [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share price at grant date	R$ 78.58
Risk-free interest rate	6.82%	6.94%
Volatility factor	32.81%	32.81%
Compass Gas e Energia [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Share price at grant date	R$ 27.27	R$ 13.58

The expected volatility of the share price used to calculate the fair value of the share options granted. Expected volatility is a measure of the amount by which a price is expected to fluctuate during a period. The measure of volatility used in option pricing models is the annualised standard deviation of the continuously compounded rates of return on the share over a period of time.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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The implied yield currently available on zero-coupon government issues of the country in whose currency the exercise price for share options granted is expressed, with a remaining term equal to the expected term of the option being valued (based on the option's remaining contractual life and taking into account the effects of expected early exercise). [Refer: Government [member]]

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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The weighted average share price used as input to the option pricing model to calculate the fair value of share options granted. [Refer: Option pricing model [member]; Weighted average [member]]

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