Line of credit facility covenant, rolling period one, minimum required hedging percentage.

No definition available.

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

- Definition

Line of credit facility covenant, rolling period two, minimum required hedging percentage.

+ References

No definition available.

+ Details

Name:	upl_LineOfCreditFacilityCovenantRollingPeriodTwoMinimumRequiredHedgingPercentage
Namespace Prefix:	upl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum hedge percentage of scheduled production requirement per revolving credit facility.

+ References

No definition available.

+ Details

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

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash inflow provided by derivative instruments during the period, which are classified as financing activities, excluding those designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3505-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=us-gaap_NaturalGasProductionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementScenarioAxis=srt_ScenarioForecastMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Derivative Financial Instruments - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended		3 Months Ended
	May 31, 2020	Apr. 30, 2020	Mar. 31, 2020	Mar. 31, 2021
Derivative [Line Items]
Proceeds from monetization of derivative contracts			$ 12.8
Subsequent Event
Derivative [Line Items]
Proceeds from monetization of derivative contracts	$ 6.5	$ 8.3
Revolving Credit Facility
Derivative [Line Items]
Maximum hedge percentage of scheduled production requirement per revolving credit facility			25.00%
Revolving Credit Facility \| Natural Gas Sales
Derivative [Line Items]
Revolving credit facility of natural gas production for the immediately succeeding twelve-month period			33.00%
Revolving credit facility of natural gas production for the immediate succeeding six-month period thereafter			25.00%
Revolving Credit Facility \| Scenario Forecast
Derivative [Line Items]
Maximum hedge percentage of scheduled production requirement per revolving credit facility				15.00%