Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2017	Apr. 24, 2017
Document and Entity Information
Entity Registrant Name	Ultra Petroleum Corp.
Entity Central Index Key	0001022646
Document Type	10-Q
Document Period End Date	Mar. 31, 2017
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		197,099,764
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q1
Trading Symbol	UPL