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FAIR VALUE MEASUREMENTS (Details 1) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Fair value adjustments included in net loss:
Crude oil price risk derivatives	$ 311	$ (1,460)
Recurring Measurements [Member]
Fair Value, Net Asset (Liability) [Roll Forward]
Fair value	1,976
Total net losses included in:
Other comprehensive loss	(324)
Fair value adjustments included in net loss:
Net unrealized gain on warrant fair value adjustment	(520)
Crude oil price risk derivatives	311
Fair value	1,443
Level 1 [Member] | Recurring Measurements [Member] | Sutter Gold Mining Company [Member] | Equity Securities [Member]
Fair Value, Net Asset (Liability) [Roll Forward]
Fair value	16
Total net losses included in:
Other comprehensive loss	(5)
Fair value adjustments included in net loss:
Net unrealized gain on warrant fair value adjustment
Crude oil price risk derivatives
Fair value	11
Level 1 [Member] | Recurring Measurements [Member] | Anfield Resources, Inc. [Member] | Equity Securities [Member]
Fair Value, Net Asset (Liability) [Roll Forward]
Fair value	930
Total net losses included in:
Other comprehensive loss	(319)
Fair value adjustments included in net loss:
Net unrealized gain on warrant fair value adjustment
Crude oil price risk derivatives
Fair value	611
Level 2 [Member] | Recurring Measurements [Member] | Derivative [Member]
Fair Value, Net Asset (Liability) [Roll Forward]
Fair value
Total net losses included in:
Other comprehensive loss
Fair value adjustments included in net loss:
Net unrealized gain on warrant fair value adjustment
Crude oil price risk derivatives	311
Fair value	311
Level 3 [Member] | Recurring Measurements [Member] | Warrant [Member]
Fair Value, Net Asset (Liability) [Roll Forward]
Fair value	1,030
Total net losses included in:
Other comprehensive loss
Fair value adjustments included in net loss:
Net unrealized gain on warrant fair value adjustment	(520)
Crude oil price risk derivatives
Fair value	$ 510

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=96868048&loc=SL4569643-111683

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=84161450&loc=SL4573702-111684

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
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-Section 45
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=96868048&loc=SL4569616-111683

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