Investments (Details Narrative) - BRL (R$) R$ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
IfrsStatementLineItems [Line Items]
Capital stock	R$ 15,000,000	R$ 15,000,000
Capital stock, shares	683,509,869
Seasamm [Member]
IfrsStatementLineItems [Line Items]
Capital stock	R$ 19,532
Capital stock, shares	19,532,409
Equity interest	36.00%
G S Inima [Member]
IfrsStatementLineItems [Line Items]
Equity interest	64.00%
Aguas De Andradina [Member]
IfrsStatementLineItems [Line Items]
Capital stock	R$ 17,936
Capital stock, shares	17,936,174
S A B E S P [Member]
IfrsStatementLineItems [Line Items]
Equity interest	30.00%
Percentage of equity interest held	45.00%
Igua Saneamento S A [Member]
IfrsStatementLineItems [Line Items]
Equity interest	70.00%
Aguas De Castilho [Member]
IfrsStatementLineItems [Line Items]
Capital stock	R$ 2,785
Capital stock, shares	2,785,225
Attend Ambiental [Member]
IfrsStatementLineItems [Line Items]
Capital stock	R$ 23,494
Capital stock, shares	37,677,245
Estre [Member]
IfrsStatementLineItems [Line Items]
Percentage of equity interest held	55.00%
Aquapolo Ambiental [Member]
IfrsStatementLineItems [Line Items]
Capital stock	R$ 36,412
Capital stock, shares	42,419,045
Paulista Geradora De Energia [Member]
IfrsStatementLineItems [Line Items]
Capital stock	R$ 13,756
Capital stock, shares	8,679,040
Equity interest	25.00%
Servtec Investimentos E Participacoes Ltda [Member]
IfrsStatementLineItems [Line Items]
Percentage of equity interest held	37.50%
Tecniplan Engenharia E Comercio Ltda [Member]
IfrsStatementLineItems [Line Items]
Percentage of equity interest held	37.50%

Indicate number of shares or other units outstanding of each of registrant's classes of capital or common stock or other ownership interests, if and as stated on cover of related periodic report. Where multiple classes or units exist define each class/interest by adding class of stock items such as Common Class A [Member], Common Class B [Member] or Partnership Interest [Member] onto the Instrument [Domain] of the Entity Listings, Instrument.

No definition available.

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