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FAIR VALUE ACCOUNTING - Fair Value Measurements, Nonrecurring (Details) | Dec. 31, 2018 USD ($)
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
United States Inflation Rate | 2.00%
Level 3 | Minimum | Nichols Ranch Project and mineral properties in the ISR and Conventional segments |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Short and Long Term Uranium Price | $ 38.90
Level 3 | Minimum | Nichols Ranch Project |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Short and Long Term Uranium Price | 37.95
Level 3 | Maximum | Nichols Ranch Project and mineral properties in the ISR and Conventional segments |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Short and Long Term Uranium Price | 62.10
Level 3 | Maximum | Nichols Ranch Project |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Short and Long Term Uranium Price | $ 65.00

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