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v3.3.1.900

Supplemental Quarterly Information (Unaudited) - Selected Quarterly Financial Information (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total revenues and other income | $ 116,063 | $ 125,479 | $ 137,630 | $ 109,677 | $ 137,273 | $ 91,609 | $ 90,561 | $ 80,309 | $ 488,849 | $ 399,752 | $ 358,117
Depreciation, depletion and amortization | 18,152 | 26,624 | 30,660 | 25,392 | 30,258 | 18,621 | 16,350 | 14,647 | 100,828 | 79,876 | 64,377
Asset impairment | 50,953 | 626,838 | 3,803 | 0 | 20,585 | 0 | 5,624 | 0 | 681,594 | 26,209 | 734
Income (loss) from operations | 2,042 | (576,290) | 55,920 | 40,417 | 31,050 | 55,027 | 50,403 | 52,439 | (477,911) | 188,919 | 236,236
Net income (loss) | $ (21,786) | $ (600,001) | $ 32,578 | $ 17,489 | $ 8,645 | $ 36,173 | $ 31,407 | $ 32,605 | $ (571,720) | $ 108,830 | $ 172,078
Net income per limited partner unit (in dollars per share) | $ (1.75) | $ (47.90) | $ 2.50 | $ 1.40 | $ 0.70 | $ 3.20 | $ 2.80 | $ 2.90 | $ (45.75) | $ 9.42 | $ 15.39
Weighted average number of common units outstanding (in shares) | 12,230 | 12,230 | 12,230 | 12,230 | 12,145 | 11,124 | 11,040 | 10,985 | 12,230 | 11,326 | 10,958
Goodwill impairment loss | $ 5,500 |  |  |  |  |  |  |  |  |  |
Impairment of intangible assets |  |  |  |  |  |  | $ 5,600 |  |  |  |
Coal Mineral Rights |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Asset impairment | 8,200 | $ 247,800 | $ 1,500 |  | $ 16,800 |  |  |  | $ 257,468 | $ 16,793 | $ 734
Oil And Gas Mineral Rights |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Asset impairment | 31,900 | 335,700 |  |  |  |  |  |  | 367,576 | 0 | $ 0
Aggregate Mineral Rights |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Asset impairment |  |  |  |  | 3,000 |  |  |  |  |  |
Hard Mineral Royalty |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Asset impairment |  | $ 43,400 |  |  |  |  |  |  | $ 43,402 | $ 3,013 |
Coal Plant |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Asset impairment |  |  | $ 2,300 |  | $ 800 |  |  |  |  |  |
Coal Processing and Transportation Assets, and Obsolete Equipment of Logan Office [Member] |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Asset impairment | 4,700 |  |  |  |  |  |  |  |  |  |
VantaCore Partners LP | Obsolete Plant and Equipment |  |  |  |  |  |  |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |
Asset impairment | $ 700 |  |  |  |  |  |  |  |  |  |

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