Identification of the name or type of counterparty to the derivative instrument.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column A

-Footnote 1

+ Details

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Namespace Prefix:	invest_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The strike price on the price risk option contract such as a put option or a call option.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	us-types:perUnitItemType
Balance Type:	na
Period Type:	instant

- Definition

Reference to the index or unit of measurement for the underlying which establishes the pricing terms of the derivative instrument. For example, the basis on the underlying for a natural gas futures contract might be the NYMEX price per million British thermal units (MMBtu).

+ References

No definition available.

+ Details

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

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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

- Definition

Value assigned to a collection of a borrower's assets, used by lenders to determine the initial and/or ongoing loan amount.

+ References

No definition available.

+ Details

Name:	useg_BorrowingBase
Namespace Prefix:	useg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Refers to the amount of limited waiver with respect to the restricted payments covenant pursuant to which a transfer from subsidiary.

+ References

No definition available.

+ Details

Name:	useg_LimitedWaiverOfCovenantRestrictedPaymentsToSubsidiary
Namespace Prefix:	useg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The quantity per day of future oil and gas production being hedged.

+ References

No definition available.

+ Details

Name:	useg_PortionOfFutureOilAndGasProductionBeingHedgedPerDay
Namespace Prefix:	useg_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
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- Details

Name:	us-gaap_TradingActivityByTypeAxis=useg_CrudeOilCostlessCollarSettlementDateElevenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_OptionIndexedToIssuersEquityTypeAxis=us-gaap_PutOptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_OptionIndexedToIssuersEquityTypeAxis=us-gaap_CallOptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
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Subsequent Events (Details) - Subsequent Event [Member]	Jul. 14, 2015 bbl $ / Barrel	Jul. 16, 2015 USD ($)	Apr. 15, 2015 USD ($)
Crude Oil Costless Collar 07/01/16 - 12/31/16 [Member]
Subsequent Event [Line Items]
Counterparty	Wells Fargo
Basis	WTI
Quantity (barrels per day) \| bbl	300
Crude Oil Costless Collar 07/01/16 - 12/31/16 [Member] \| Put Option [Member]
Subsequent Event [Line Items]
Strike Price (in dollars per barrel)	50.00
Crude Oil Costless Collar 07/01/16 - 12/31/16 [Member] \| Call Option [Member]
Subsequent Event [Line Items]
Strike Price (in dollars per barrel)	65.25
Revolving Credit Facility [Member]
Subsequent Event [Line Items]
Borrowing base \| $			$ 7,000,000
Limited waiver of covenant restricted payments to subsidiary \| $		$ 5,000,000