XML 92 R72.htm IDEA: XBRL DOCUMENT
v3.21.1

Fair Value Measurements (Details Narrative) $ / shares in Units, $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 USD ($) $ / shares | Dec. 31, 2019 USD ($) $ / shares
Warrant strike price | $ / shares | $ 3.92 | $ 11.30
Average value of warrants |  | $ 73
Fair value of marketable equity securities | $ 0 |
Measurement Input, Discount Rate [Member] |  |
Fair value meaeurement input | 10 |
Minimum [Member] |  |
Average value of warrants |  | 60
Maximum [Member] |  |
Average value of warrants |  | $ 120

X
- Definition Average value of warrants. + References No definition available. + Details
Name: | USEG_AverageValueOfWarrants
Namespace Prefix: | USEG_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition fair value of marketable equity securities. + References No definition available. + Details
Name: | USEG_FairValueOfMarketableEquitySecurities
Namespace Prefix: | USEG_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Exercise price per share or per unit of warrants or rights outstanding. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644 + Details
Name: | us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Value of input used to measure outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
Name: | us-gaap_WarrantsAndRightsOutstandingMeasurementInput
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputDiscountRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |