Represents the daily volume distribution target of biomethane under ESG goals.

No definition available.

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- Definition

The description of additional estimated interest rate increase for non-compliance for fulfilment of environment goals such as greenhouse gas emissions, usage of recycled plastic in packaging.

+ References

No definition available.

+ Details

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- Definition

The description of estimated interest rate decrease for compliance for fulfilment of environment goals such as greenhouse gas emissions.

+ References

No definition available.

+ Details

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- Definition

The description of estimated interest rate increase for non-compliance for fulfilment of environment goals such as greenhouse gas emissions, usage of recycled plastic in packaging.

+ References

No definition available.

+ Details

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- Definition

The estimated interest rate increase for non-compliance for fulfilment of environment goals such as greenhouse gas emissions, usage of recycled plastic in packaging.

+ References

No definition available.

+ Details

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- Definition

Represents the increase in daily volume distributed of biomethane under ESG target.

+ References

No definition available.

+ Details

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- Definition

The percentage of ESG (environmental, social and governance) target panel for information security maturity, as well as Internal Controls maturity of the reporting entity.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the percentage of leadership positions from diversity groups under ESG goals.

+ References

No definition available.

+ Details

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Namespace Prefix:	csan_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the target rate of greenhouse gas emissions reduction per ton of useful kilometer by 2023.

+ References

No definition available.

+ Details

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Namespace Prefix:	csan_
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Balance Type:	na
Period Type:	instant

- Definition

Represents the target rate of greenhouse gas emissions reduction per ton of useful kilometer by 2026.

+ References

No definition available.

+ Details

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- Definition

Represents the target rate of greenhouse gas emissions reduction per ton of useful kilometer by 2030.

+ References

No definition available.

+ Details

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Namespace Prefix:	csan_
Data Type:	dtr-types:percentItemType
Balance Type:	na
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- Definition

The amount of outstanding funds that the entity is obligated to repay.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2024-01-01
-Paragraph 55
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_55&doctype=Standard
-URIDate 2024-03-27

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The basis (reference rate) used for calculation of the interest rate on borrowings. [Refer: Borrowings]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 7
-IssueDate 2024-01-01
-Paragraph 7
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_7&doctype=Standard
-URIDate 2024-03-27

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
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- Definition

The maturity of borrowings. [Refer: Borrowings]

+ References

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

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- Details

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STATEMENT OF COMPLIANCE AND MATERIAL ACCOUNTING POLICIES - Additional Information (Details) - BRL (R$) R$ in Thousands		12 Months Ended
	Nov. 01, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disclosure of detailed information about borrowings [line items]
Amount		R$ 66,455,426	R$ 56,904,654	R$ 52,987,216
Percentage of ESG (environmental, social and governance) target panel for information security maturity and Internal Controls maturity		10.00%
Senior Notes Due 2032 [Member]
Disclosure of detailed information about borrowings [line items]
Target rate of greenhouse gas emissions reduction per ton of useful kilometer by 2026		17.60%
Description of Estimated Interest Rate Increase for Non Compliance for Fulfilment of Environment Goals		25
Estimated Interest Rate Increase for Non Compliance for Fulfilment of Environment Goals		4.45%
Debentures Seventeenth Issue Member
Disclosure of detailed information about borrowings [line items]
Target rate of greenhouse gas emissions reduction per ton of useful kilometer by 2026		17.60%
Target rate of greenhouse gas emissions reduction per ton of useful kilometer by 2030		21.60%
Description of Estimated Interest Rate Increase for Non Compliance for Fulfilment of Environment Goals		25
Swaps Debentures
Disclosure of detailed information about borrowings [line items]
Annual interest rate		IPCA + 4.52%
Description of estimated interest rate decrease for compliance for fulfilment of environment goals		25
Swaps Debentures \| Rumo Malha Paulista S.A. [member]
Disclosure of detailed information about borrowings [line items]
Target rate of greenhouse gas emissions reduction per ton of useful kilometer by 2023		15.00%
Nonconvertible Debentures [Member] \| Compass Gas E Energia S A [Member]
Disclosure of detailed information about borrowings [line items]
Annual interest rate	CDI + 1.55%	CDI + 1.80%
Description of estimated interest rate decrease for compliance for fulfilment of environment goals		12.5
Amount	R$ 1,736,385
Maturities	November 1, 2029 (50%) and November 1, 2030
Increase In Daily Volume Distributed Of Biomethane Under Environment Goals		250
Daily Volume Distribution Target Of Biomethane Under Environment Goals		0.25mln/m³ day
Percentage Of Leadership Position From Diversity Groups		47.00%
Debenture 17th issue - 2nd series
Disclosure of detailed information about borrowings [line items]
Description of Estimated Interest Rate Increase for Non Compliance for Fulfilment of Environment Goals		20
Description of Additional Estimated Interest Rate Increase for Non Compliance for Fulfilment of Environment Goals		5