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Summary of Significant Accounting Policies - Additional Information (Detail) shares in Millions |  | 3 Months Ended | 12 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Feb. 18, 2016 shares | Dec. 31, 2015 USD ($) shares | Dec. 31, 2015 USD ($) shares | Mar. 01, 2016 shares | Feb. 17, 2016 shares | Dec. 31, 2014 USD ($) shares | Oct. 31, 2014 | Sep. 30, 2013
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Rate of senior notes |  | 9.125% | 9.125% |  |  |  |  |
Long-term debt |  | $ 1,384,996,000 | $ 1,384,996,000 |  |  | $ 1,475,223,000 |  |
Common units outstanding (in shares) | shares |  | 12.2 | 12.2 |  |  | 12.2 |  |
Common units outstanding (in shares) | shares |  |  |  | 12.2 |  |  |  |
Allowance for doubtful accounts |  | $ 5,300,000 | $ 5,300,000 |  |  | $ 700,000 |  |
Oil and gas royalty interests useful life (in years) |  |  | 30 years |  |  |  |  |
Asset impairment |  |  | $ 676,100,000 |  |  |  |  |
Impairment loss |  | $ 5,500,000 |  |  |  |  |  |
Minimum [Member] |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Ownership interest of Partnership with significant influence (percent) |  | 20.00% | 20.00% |  |  |  |  |
Maximum [Member] |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Ownership interest of Partnership with significant influence (percent) |  | 50.00% | 50.00% |  |  |  |  |
Restatement Adjustment [Member] |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Depletion |  |  | $ (3,800,000) |  |  |  |  |
Subsequent Event [Member] |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Common units outstanding (in shares) | shares | 12.2 |  |  |  | 122.3 |  |  |
NRP LP |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Rate of senior notes |  |  |  |  |  |  | 9.125% | 9.125%
NRP LP | 9.125% senior notes, with semi-annual interest payments in April and October, maturing October 2018 |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Debt Instrument, face Amount |  | $ 425,000,000 | $ 425,000,000 |  |  |  |  |
Rate of senior notes |  | 9.125% | 9.125% |  |  |  |  |
Long-term debt |  | $ 422,923,000 | $ 422,923,000 |  |  | 422,167,000 |  |
NRP LP | Senior Notes |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Rate of senior notes |  | 9.125% | 9.125% |  |  |  |  |
Long-term debt |  | $ 422,900,000 | $ 422,900,000 |  |  |  |  |
Opco |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Ratio of consolidated indebtedness to consolidated EBITDDA |  |  | 4.0 |  |  |  |  |
Opco | $300 million floating rate revolving credit facility, due October 2017 |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Long-term debt |  | 290,000,000 | $ 290,000,000 |  |  | 0 |  |
Opco | Senior Notes |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Long-term debt |  | 585,900,000 | $ 585,900,000 |  |  |  |  |
NRP Oil and Gas |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Leverage ratio, maximum |  |  | 3.5 |  |  |  |  |
Revolving Credit Facility | Opco | Fiscal Quarter Ending on or Before March 31, 2016 [Member] |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Ratio of consolidated indebtedness to consolidated EBITDDA |  |  | 4.0 |  |  |  |  |
Revolving Credit Facility | Opco | Fiscal Quarter Ending on or Before March 31, 2017 [Member] |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Ratio of consolidated indebtedness to consolidated EBITDDA |  |  | 3.75 |  |  |  |  |
Revolving Credit Facility | Opco | Fiscal Quarter Ending on or After June 30, 2017 [Member] |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Ratio of consolidated indebtedness to consolidated EBITDDA |  |  | 3.5 |  |  |  |  |
Revolving Credit Facility | NRP Oil and Gas |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Borrowings outstanding |  | $ 85,000,000 | $ 85,000,000 |  |  | $ 110,000,000 |  |
Leverage ratio, maximum |  |  | 3.5 |  |  |  |  |
Common Stock [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Reverse split ratio, common units | 0.1 |  |  |  |  |  |  |
VantaCore |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Impairment loss |  |  | $ 5,500,000 |  |  |  |  |
Brp Llc [Member] |  |  |  |  |  |  |  |
Schedule Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Percentage of partnership interest owned (percent) |  | 51.00% | 51.00% |  |  |  |  |

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