Trade accounts receivables - Breakdown of trade accounts receivable by maturity (Details) - Trade accounts receivable - BRL (R$) R$ in Thousands	Dec. 31, 2026	Mar. 31, 2026	Dec. 31, 2025
Trade Accounts Receivables [Line Items]
Current financial assets		R$ 5,766,623	R$ 6,560,607
Current \| Current
Trade Accounts Receivables [Line Items]
Current financial assets		4,983,143	5,794,713
Overdue \| Up to 30 days
Trade Accounts Receivables [Line Items]
Current financial assets	R$ 536,862		465,967
Overdue \| From 31 to 60 days
Trade Accounts Receivables [Line Items]
Current financial assets		84,518	89,398
Overdue \| From 61 to 90 days
Trade Accounts Receivables [Line Items]
Current financial assets		38,425	44,305
Overdue \| From 91 to 120 days
Trade Accounts Receivables [Line Items]
Current financial assets		20,570	21,225
Overdue \| From 121 to 180 days
Trade Accounts Receivables [Line Items]
Current financial assets		24,764	45,072
Overdue \| From 181 days
Trade Accounts Receivables [Line Items]
Current financial assets		R$ 78,341	R$ 99,927