Chapter 11 Proceedings, Ability to Continue as a Going Concern Disclosure (Narratives) (Details)	Sep. 30, 2016
Chapter 11 Proceedings [Abstract]
NOL Order Beneficial Ownership Percentage	4.50%

NOL Order beneficial ownership percentage requirement.

No definition available.

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Namespace Prefix:	upl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant