Taxes to Recover - Summary of Provision for ICMS Losses (Detail) - BRL (R$) R$ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Summary of recoverable taxes [abstract]
Additions, write-offs and reversals, net	R$ 27,111	R$ 3,393	R$ 3,792
Provision for ICMS losses, ending	R$ 99,187	R$ 72,076	R$ 68,683	R$ 64,891

Net balance of Write-offs, additions and reversals on Provision for losses regarding the excess of amount paid for ICMS (Brazilian tax on goods and services) expected to be recovered in the future.

No definition available.

Name:	ugp_WriteoffsAdditionsReversalsOficmsProvision
Namespace Prefix:	ugp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration