v3.19.1

INCOME TAXES (Tables) | 12 Months Ended
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Dec. 31, 2018
Income Tax Disclosure [Abstract] |
Schedule of Income Tax Provision | A summary of the provision for income taxes is as follows (in thousands):
|  | Year Ended December 31,
|  | 2018 |  | 2017 |  | 2016
Current portion of income tax expense (benefit): |  |  |  |  |  |
Federal |  | $ | 23 |  |  | $ | (2,793 | ) |  | $ | (1,365 | )
State |  | 85 |  |  | 10 |  |  | 3 |
Deferred portion of income tax expense: |  |  |  |  |  |
Federal |  | — |  |  | — |  |  | — |
State |  | — |  |  | — |  |  | — |
Total income tax expense (benefit) |  | $ | 108 |  |  | $ | (2,783 | ) |  | $ | (1,362 | )
Reconciliation of The Statutory Rate to The Effective Rate | A reconciliation of the federal statutory income tax rate of 21% for 2018 and 35% for 2017 and 2016 to our effective rate is as follows (in thousands, except percentages):
|  | Year Ended December 31,
|  | 2018 |  | 2017 |  | 2016
Federal taxes at statutory rate |  | $ | 2,497 |  |  | $ | (8,873 | ) |  | $ | (22,941 | )
Add: |  |  |  |  |  |  |  |  |
State taxes, net of federal benefit |  | 1,663 |  |  | (1,414 | ) |  | (4,982 | )
Change in valuation allowance |  | (3,330 | ) |  | (104,710 | ) |  | 24,522 |
Change in federal and state tax rates |  | 634 |  |  | 115,545 |  |  | — |
Percentage depletion |  | (656 | ) |  | (598 | ) |  | (552 | )
Other |  | (700 | ) |  | (2,733 | ) |  | 2,591 |
Net expense (benefit) as calculated |  | $ | 108 |  |  | $ | (2,783 | ) |  | $ | (1,362 | )
Effective tax rate |  | 0.9 | % |  | 11.0 | % |  | 2.1 | %
Schedule of Net Deferred Tax Assets | Significant components of our deferred tax assets and liabilities were as follows (in thousands):
|  | December 31,
|  | 2018 |  | 2017
Deferred tax assets (liabilities): |  |  |  |
Property, plant, equipment and mineral properties, net |  | $ | 138,855 |  |  | $ | 139,656 |
Federal and state net operating loss carryforwards |  | 65,779 |  |  | 68,733 |
Other |  | 2,888 |  |  | 5,976 |
Asset retirement obligation |  | 5,950 |  |  | 5,472 |
R&D credits |  | 1,870 |  |  | 1,870 |
Deferred revenue |  | 3,035 |  |  | — |
Total deferred tax assets |  | 218,377 |  |  | 221,707 |
Valuation allowance |  | (218,377 | ) |  | (221,707 | )
Deferred tax asset, net |  | $ | — |  |  | $ | — |

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- Definition Tabular disclosure of the components of income tax expense attributable to continuing operations for each year presented including, but not limited to: current tax expense (benefit), deferred tax expense (benefit), investment tax credits, government grants, the benefits of operating loss carryforwards, tax expense that results from allocating certain tax benefits either directly to contributed capital or to reduce goodwill or other noncurrent intangible assets of an acquired entity, adjustments of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity, and adjustments of the beginning-of-the-year balances of a valuation allowance because of a change in circumstances that causes a change in judgment about the realizability of the related deferred tax asset in future years. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319 + Details
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- Definition Tabular disclosure of the components of net deferred tax asset or liability recognized in an entity's statement of financial position, including the following: the total of all deferred tax liabilities, the total of all deferred tax assets, the total valuation allowance recognized for deferred tax assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 + Details
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- Definition Tabular disclosure of the reconciliation using percentage or dollar amounts of the reported amount of income tax expense attributable to continuing operations for the year to the amount of income tax expense that would result from applying domestic federal statutory tax rates to pretax income from continuing operations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
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