Investment held in a trust fund to pay the cost of sustainability with respect to water rights and permitting.

No definition available.

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- Definition

Accrual for trust to be established upon certain achievements of milestones.

+ References

No definition available.

+ Details

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- Definition

The total amount of cash and securities held by third party trustees pursuant to terms of debt instruments or other agreements as of the date of each statement of financial position presented, which can be used by the trustee only to pay the noncurrent portion of specified obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(b))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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Balance Type:	credit
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- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease, due in next fiscal year following latest fiscal year.

+ References

+ Details

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

- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third fiscal year following latest fiscal year.

+ References

+ Details

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

- Definition

Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

+ References

+ Details

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

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980

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- References

No definition available.

+ Details

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- Details

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COMMITMENTS AND CONTINGENCIES - Obligations Under Operating Leases (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Aug. 19, 2019	Aug. 18, 2019
Operating lease obligations
Total expected payments for operating lease for the next three years	$ 0.1
Lease term	3 years
Expected payments for operating lease, next 12 months	$ 0.1
Expected payments for operating lease, 12 to 24 months	0.0
Expected payments for operating lease, 24 to 36 months	0.0
Mt. Hope Project
Operating lease obligations
Sustainability Trust fund asset amount			$ 4.0
Eureka Moly LLC
Operating lease obligations
Sustainability Trust fund asset amount		$ 5.6	$ 4.0
Paid into trust	0.1
Accrual for trust to be established upon certain achievements of milestones	$ 5.6
Eureka Moly LLC \| Mt. Hope Project
Operating lease obligations
Lease term	30 years