The cash inflow adjustment related to revenue.

No definition available.

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Namespace Prefix:	useg_
Data Type:	xbrli:monetaryItemType
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- Definition

Represents the expected net revenue interests in new wells after sale.

+ References

No definition available.

+ Details

Name:	useg_ExpectedNetRevenueInterestsInNewWellsAfterSale
Namespace Prefix:	useg_
Data Type:	num:percentItemType
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- Definition

The initial well commitment under the terms of the agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	useg_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represent the minimum percentage of net revenue interest in lease owned as per the agreement.

+ References

No definition available.

+ Details

Name:	useg_MinimumPercentageOfNetRevenueInterestInLeasesOwned
Namespace Prefix:	useg_
Data Type:	num:percentItemType
Balance Type:	na
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- Definition

Proceeds from the transaction after deduction of payment of the note, commission and other closing costs.

+ References

No definition available.

+ Details

Name:	useg_NetProceedsOnTransaction
Namespace Prefix:	useg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Area spaced or assigned to productive wells in which a working interest is owned.

+ References

No definition available.

+ Details

Name:	useg_NetSalesOfAcres
Namespace Prefix:	useg_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

Represent percentage of working interest retained.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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- Definition

Represent percentage payout of all costs.

+ References

No definition available.

+ Details

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- Definition

A percentage of ownership in an oil and gas lease granting its owner the right to explore, drill and produce oil and gas from a tract of property. Working interest owners are obligated to pay a corresponding percentage of the cost of leasing, drilling, producing and operating a well or unit. After royalties are paid, the working interest also entitles its owner to share in production revenues with other working interest owners, based on the percentage of working interest owned.

+ References

No definition available.

+ Details

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

+ Details

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Balance Type:	credit
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- Definition

Area spaced or assigned to productive wells in which a working interest is owned.

+ References

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

-Publisher SEC

-Name Industry Guide

-Number 2

-Paragraph 4

-Subparagraph A

+ Details

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Balance Type:	na
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- Definition

Fractional interest owned based on working interests or other economic arrangements of area spaced or assigned to productive wells.

+ References

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

-Publisher SEC

-Name Industry Guide

-Number 2

-Paragraph 4

-Subparagraph A

+ Details

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Balance Type:	na
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- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

The total number of producing oil wells and oil wells capable of production, in which the entity owns an undivided working interest.

+ References

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

-Publisher SEC

-Name Industry Guide

-Number 2

-Paragraph 4

-Subparagraph A

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Details

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Acquisitions and Divestitures (Details) (USD $)	9 Months Ended			0 Months Ended					0 Months Ended	3 Months Ended
Acquisitions and Divestitures (Details) (USD $)	Sep. 30, 2014	Sep. 30, 2013	Jan. 21, 2014 acre	May 07, 2014 Farm in Acreage [Member] Wells	May 07, 2014 South Texas Based Oil and Gas Company [Member]	May 07, 2014 Dimmit County [Member] acre	May 07, 2014 Dimmit County [Member] Primary Leasehold Acreage [Member] acre	May 07, 2014 Dimmit County [Member] Farm in Acreage [Member] acre	May 07, 2014 Farmor [Member] Wells	Jun. 30, 2014 Williams and McKenzie Counties [Member]	May 27, 2014 Williams and McKenzie Counties [Member] acre
Acquisitions and Divestitures [Line Items]
Percentage interest acquired (in hundredths)			50.00%		33.00%
Gross acres acquired in acquisition (in acres)			160			12,100	4,020	8,080			16
Net acres acquired in acquisition (in acres)						3,384	1,181	2,203			0.62
Initial well commitment				2
Number of developed wells in which our original working interest is retained									10
Minimum percentage of net revenue interest in lease owned (in hundredths)				12.50%
Percentage payout of all costs (in hundredths)					100.00%
Percentage of working interest retained (in hundredths)									25.00%
Expected net revenue interests in new wells after sale					115.00%
Cost of acquisition					$ 3,900,000
Net proceeds on transaction										12,200,000
Adjustment related to revenue										681,000
Proceeds from sale of assets held for sale	$ 28,000	$ 2,596,000								$ 11,500,000
Net sales of acres (in acres)											285.7