Revenue (Details) - BRL (R$) R$ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Disclosure Revenue Abstract
Revenue	R$ 26,624,721	R$ 25,447,930	R$ 23,833,893
Gross revenue	40,279,063	36,731,708	33,530,346
Service revenue	38,631,519	35,041,192	31,972,936
Service revenue - Mobile	36,286,661	33,070,752	30,020,711
Service revenue - Landline	2,344,858	1,970,440	1,952,225
Goods sold	1,647,544	1,690,516	1,557,410
Deductions from gross revenue	(13,654,342)	(11,283,778)	(9,696,453)
Taxes levied	(4,045,145)	(4,014,344)	(3,657,281)
Discounts granted	(9,593,647)	(7,253,635)	(6,030,865)
Returns and other	R$ (15,550)	R$ (15,799)	R$ (8,307)

The income arising in the course of an entity's ordinary activities. Income is increases in assets, or decreases in liabilities, that result in increases in equity, other than those relating to contributions from holders of equity claims.

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