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v3.3.1.900

Related Party Transactions - Additional Information (Detail) - USD ($) shares in Thousands | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Oct. 31, 2014 | 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
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Amount payable to related parties |  | $ 1,464,000 |  |  |  | $ 950,000 |  |  |  | $ 1,464,000 | $ 950,000 |
Lease expenses |  |  |  |  |  |  |  |  |  | 600,000 |  |
Revenues |  | 116,063,000 | $ 125,479,000 | $ 137,630,000 | $ 109,677,000 | 137,273,000 | $ 91,609,000 | $ 90,561,000 | $ 80,309,000 | 488,849,000 | 399,752,000 | $ 358,117,000
Unrecouped minimum royalty payments |  |  |  |  |  |  |  |  |  | 82,600,000 |  |
Contracts receivable—affiliate, current and long-term |  | 4,891,000 |  |  |  | 4,870,000 |  |  |  | 4,891,000 | 4,870,000 |
Accounts receivable |  | $ 6,864,000 |  |  |  | 9,494,000 |  |  |  | 6,864,000 | 9,494,000 |
Gain on reserve swaps |  |  |  |  |  |  |  |  |  | $ 9,300,000 | 5,700,000 | 8,100,000
Rate of senior notes |  | 9.125% |  |  |  |  |  |  |  | 9.125% |  |
Deferred revenue—affiliates |  | $ 82,853,000 |  |  |  | 87,053,000 |  |  |  | $ 82,853,000 | 87,053,000 |
Operating and maintenance expenses—affiliates, net |  |  |  |  |  |  |  |  |  | 16,031,000 | 10,770,000 | 8,821,000
Quintana Minerals |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Amount payable to related parties |  | 1,100,000 |  |  |  | 600,000 |  |  |  | 1,100,000 | 600,000 |
Western Pocahontas Properties |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Amount payable to related parties |  | 300,000 |  |  |  | 400,000 |  |  |  | $ 300,000 | 400,000 |
Cline Affiliates [Member] |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Rate of interest in the partnerships general partner |  |  |  |  |  |  |  |  |  | 31.00% |  |
Related party transaction number of units hold by the related party in partnerships' general partner |  |  |  |  |  |  |  |  |  | 500 |  |
Accounts receivable |  | 6,400,000 |  |  |  | 9,200,000 |  |  |  | $ 6,400,000 | 9,200,000 |
Net amount receivable |  |  |  |  |  | 5,600,000 |  |  |  |  | 5,600,000 |
Accounts receivable |  |  |  |  |  | 1,100,000 |  |  |  |  | 1,100,000 |
Cline Affiliates [Member] |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net amount receivable |  | 4,900,000 |  |  |  |  |  |  |  | 4,900,000 |  |
Accounts receivable |  | 1,500,000 |  |  |  |  |  |  |  | 1,500,000 |  |
Foresight Energy Lp [Member] | Affiliated Entity |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Lease receivable, next year |  | 5,000,000 |  |  |  |  |  |  |  | 5,000,000 |  |
Deficiency payment |  | 1,250,000 |  |  |  |  |  |  |  | 1,250,000 |  |
Foresight Energy Lp [Member] | Coal Sales [Member] |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  | 86,600,000 | 81,500,000 | 88,400,000
Sugar Camp [Member] |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Contracts receivable—affiliate, current and long-term |  | 81,200,000 |  |  |  | 86,300,000 |  |  |  | 81,200,000 | 86,300,000 |
Unearned income |  | 35,400,000 |  |  |  | 39,000,000 |  |  |  | 35,400,000 | 39,000,000 |
Net amount receivable |  | 45,900,000 |  |  |  | 47,300,000 |  |  |  | 45,900,000 | 47,300,000 |
Accounts receivable |  | 2,000,000 |  |  |  | 1,800,000 |  |  |  | 2,000,000 | 1,800,000 |
Sugar Camp [Member] | Affiliated Entity |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Lease receivable, year two |  | 5,000,000 |  |  |  |  |  |  |  | 5,000,000 |  |
Lease receivable, year three |  | 5,000,000 |  |  |  |  |  |  |  | 5,000,000 |  |
Lease receivable, year four |  | 5,000,000 |  |  |  |  |  |  |  | 5,000,000 |  |
Lease receivable, year five |  | 5,000,000 |  |  |  |  |  |  |  | 5,000,000 |  |
Corsa [Member] |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Accounts receivable |  | 200,000 |  |  |  | 300,000 |  |  |  | 200,000 | 300,000 |
Royalty Revenue from Coal |  |  |  |  |  |  |  |  |  | 3,100,000 | 3,000,000 | 4,600,000
Deferred revenue—affiliates |  | 300,000 |  |  |  |  |  |  |  | 300,000 |  |
Forge Group [Member] |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Coal, hard mineral royalty and other—affiliates |  |  |  |  |  |  |  |  |  |  |  | 1,800,000
Western Pocahontas Properties Limited Partnership [Member] | Affiliated Entity |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Operating and maintenance expenses—affiliates, net |  |  |  |  |  |  |  |  |  | 400,000 | 0 | $ 0
Other assets—affiliate |  | $ 1,100,000 |  |  |  | 0 |  |  |  | $ 1,100,000 | 0 |
Senior Notes Due Two Zero One Eight [Member] | Cline Trust Company [Member] |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Partnership common units owned |  | 540 |  |  |  |  |  |  |  | 540 |  |
Principal amount of partnership purchased | $ 20,000,000 |  |  |  |  |  |  |  |  | $ 20,000,000 |  |
Rate of senior notes | 9.125% | 9.125% |  |  |  |  |  |  |  | 9.125% |  |
Aggregate principal amount of senior notes | $ 125,000,000 |  |  |  |  |  |  |  |  |  |  |
Senior notes due |  | $ 19,900,000 |  |  |  | $ 19,900,000 |  |  |  | $ 19,900,000 | $ 19,900,000 |

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