Capitalized costs of unevaluated property included in amortization base.

No definition available.

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- Definition

The sum of the capitalized costs incurred, as of the balance sheet date, of unproved properties and wells in progress excluded from amortization including acquisition costs, exploration costs, development costs, and production costs.

+ References

No definition available.

+ Details

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- Definition

Represents the number of cost centers for quarterly ceiling test for oil and gas.

+ References

No definition available.

+ Details

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- Definition

Represents the percentage of discount used for future net revenue.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Definition

Represents the period prior to the end of reporting period during which unescalated average prices per barrel of oil and per MMbtu of natural gas are calculated.

+ References

No definition available.

+ Details

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- Definition

Represents the price per barrel of natural gas at ceiling test.

+ References

No definition available.

+ Details

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Data Type:	xbrli:decimalItemType
Balance Type:	na
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- Definition

Represents the price per barrel for oil at ceiling test.

+ References

No definition available.

+ Details

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Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of wells in progress.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

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-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 14

-Article 5

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Balance Type:	credit
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- Definition

Capitalized costs of proved properties incurred for any combination mineral interests acquisitions; wells and related equipment; support equipment and facilities; and uncompleted wells and equipment and other costs not previously disclosed within this table.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section 50

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e61901-109447

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 360

-Glossary Proved Properties

-URI http://asc.fasb.org/extlink&oid=6522428

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Properties

-URI http://asc.fasb.org/extlink&oid=21914647

+ Details

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Balance Type:	debit
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- Definition

Capitalized costs of which include those incurred to (1) drill and equip wells that are not yet completed (2) acquire or construct equipment and facilities that are not yet installed.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 235

-Section 50

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=8451039&loc=d3e61901-109447

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Uncompleted Wells, Equipment, and Facilities

-URI http://asc.fasb.org/extlink&oid=6527447

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

The expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Name Accounting Standards Codification

-Topic 932

-SubTopic 360

-Section 35

-Paragraph 11

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-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2921-110230

+ Details

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

- Definition

Mineral properties, net of adjustments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

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-Name Accounting Standards Codification

-Topic 932

-SubTopic 360

-Section 25

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6474861&loc=d3e64895-109465

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

- Details

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

- Definition

Depletion of oil and gas property carried under the full cost method.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Oil and gas properties, gross, carried under the full cost method.

+ References

No definition available.

+ Details

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

- Definition

Oil and gas properties, net of depletion, carried under the full cost method.

+ References

No definition available.

+ Details

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

- Details

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- Details

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Balance Type:	na
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- Definition

Amount before accumulated depreciation, depletion and amortization of other physical assets used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The net amount of capitalized assets classified as property, plant and equipment not otherwise defined in the taxonomy.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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Period Type:

- Details

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- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_OfficeEquipmentMember
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- Details

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, PROPERTY, PLANT AND EQUIPMENT (Details) (USD $)	12 Months Ended
	Dec. 31, 2014 DollarUSPerMillionsofBTU Center	Dec. 31, 2013	Dec. 31, 2012
Oil and Gas properties [Abstract]
Proved	$ 147,486,000	$ 136,521,000
Unproved	10,188,000	7,478,000
Exploratory wells in progress	2,357,000useg_WellsInProgress	0useg_WellsInProgress
Oil & Gas properties	160,031,000	143,999,000
Less accumulated depreciation depletion and amortization	(71,762,000)	(57,077,000)
Net book value	88,269,000	86,922,000
Mining properties	21,942,000us-gaap_MineralPropertiesNet	20,739,000us-gaap_MineralPropertiesNet
Property, plant and equipment	8,346,000us-gaap_PropertyPlantAndEquipmentOther	8,334,000us-gaap_PropertyPlantAndEquipmentOther
Less accumulated depreciation	(4,404,000)	(4,135,000)
Net book value	3,942,000	4,199,000
Oil and Gas Properties [Abstract]
Capitalized costs excluded from amortized cost pool	12,500,000	7,500,000
Capitalized costs related to unevaluated properties included in the amortization base	0	0
Percentage of discount used for future net revenue (in hundredths)	10.00%
Period for calculating unescalated average prices prior to the end of reporting period	12 months
Number of cost centers for quarterly ceiling test for oil and gas	1
Price per barrel for oil at ceiling test (in dollars per barrel)	94.99useg_PricePerBarrelForOilAtCeilingTest
Price for natural gas at ceiling test (dollars per MMbtu)	4.35
Proved property impairments	$ 0us-gaap_ImpairmentOfOilAndGasProperties	$ 5,828,000us-gaap_ImpairmentOfOilAndGasProperties	$ 5,189,000us-gaap_ImpairmentOfOilAndGasProperties
Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years
Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	45 years
Office Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years
Office Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Field Tools and Hand Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Field Tools and Hand Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	7 years
Vehicles and Trucks [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years
Vehicles and Trucks [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	7 years
Heavy Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	7 years
Heavy Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	10 years
Service Buildings [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	20 years
Corporate Headquarter Building [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	45 years