Earnings per Share - Weighted Average Shares Outstanding (Detail) - shares	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings per share details 1 [abstract]
Weighted average shares outstanding for basic per share calculation	1,084,128,000	1,083,825,000	1,082,782,000
Subscription warrants-indemnification	4,603,000	4,791,000	4,535,000
Deferred Stock Plan	2,602,000	3,064,000	3,702,000
Weighted average shares outstanding for diluted per share calculation	1,091,335,000	1,091,605,000	1,091,019,000

The weighted average number of ordinary shares outstanding plus the weighted average number of ordinary shares that would be issued on the conversion of all the dilutive potential ordinary shares into ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]]

No definition available.

Name:	ugp_WeightedAverageSharesDiluted
Namespace Prefix:	ugp_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration