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Debt and Debt - Affiliate - Additional Information (Detail) | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |  |
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Sep. 30, 2015 USD ($) | Jun. 30, 2015 USD ($) | Oct. 31, 2014 USD ($) | Sep. 30, 2013 USD ($) | Aug. 31, 2013 USD ($) | Dec. 31, 2014 USD ($) | Sep. 30, 2013 USD ($) | Dec. 31, 2015 USD ($) | Dec. 31, 2013 USD ($) | Oct. 31, 2015 USD ($) | Apr. 30, 2015 USD ($) | Nov. 30, 2014 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Rate of senior notes |  |  |  |  |  |  |  | 9.125% |  |  |  |
Term Loan [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Repayment of principal amount | $ 75,000,000 |  |  |  |  | $ 24,000,000 | $ 101,000,000 |  |  |  |  |
Amount received from debt issuance |  |  |  |  |  |  |  |  | $ 200,000,000 |  |  |
Weighted average interest rate for the debt outstanding (percent) |  |  |  |  |  | 2.22% |  | 2.19% |  |  |  |
Nrp Lp Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Redemption price percentage (percent) |  |  |  |  |  |  |  | 109.125% |  |  |  |
Redemption price at change of control event (percent) |  |  |  |  |  |  |  | 101.00% |  |  |  |
Ciner Wyoming |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Percentage of partnership interest owned (percent) |  |  |  |  |  |  |  | 49.00% |  |  |  |
Ciner Wyoming | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Percentage of partnership interest owned (percent) |  |  |  |  |  |  |  | 49.00% |  |  |  |
Maximum [Member] | Nrp Lp Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Percentage of principal amount redeemed (up to) |  |  |  |  |  |  |  | 35.00% |  |  |  |
Redemption period (in days) |  |  |  |  |  |  |  | 180 days |  |  |  |
Minimum [Member] | Nrp Lp Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Redemption price percentage of principal remaining after redemption (percent) |  |  |  |  |  |  |  | 65.00% |  |  |  |
NRP LP |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Rate of senior notes |  |  | 9.125% | 9.125% |  |  | 9.125% |  |  |  |  |
Floating rate revolving credit facility |  |  | $ 125,000,000 | $ 300,000,000.0 |  |  | $ 300,000,000.0 |  |  |  |  |
Senior Note issue percentage |  |  | 99.50% | 99.007% |  |  | 99.007% |  |  |  |  |
Repayment of principal amount |  |  | $ 122,600,000 |  |  |  |  |  |  |  |  |
NRP LP | 9.125% senior notes, with semi-annual interest payments in April and October, maturing October 2018 |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Rate of senior notes |  |  |  |  |  |  |  | 9.125% |  |  |  |
Debt Instrument, face Amount |  |  |  |  |  |  |  | $ 425,000,000 |  |  |  |
NRP LP | Senior Notes |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Rate of senior notes |  |  |  |  |  |  |  | 9.125% |  |  |  |
NRP LP | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Fixed charge coverage ratio |  |  |  |  |  |  |  | 2.0 |  |  |  |
NRP LP | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Fixed charge coverage ratio |  |  |  |  |  |  |  | 1.0 |  |  |  |
Opco |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Repayment of principal amount |  |  |  | $ 289,000,000 |  |  |  |  |  |  |  |
Ratio of consolidated indebtedness to consolidated EBITDDA |  |  |  |  |  |  |  | 4.0 |  |  |  |
Ratio of consolidated EBITDDA to consolidated fixed charges |  |  |  |  |  |  |  | 3.5 |  |  |  |
Principal payments on its senior notes |  |  |  |  |  |  |  | $ 80,800,000 |  |  |  |
Percentage of consolidated net tangible assets debt of subsidiaries not permitted to exceed |  |  |  |  |  |  |  | 10.00% |  |  |  |
Opco | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate (percent) |  |  |  |  |  | 1.98% |  | 2.91% |  |  |  |
Commitment fee on the unused portion of the borrowing base under the credit facility (percent) |  |  |  |  |  |  |  | 0.50% |  |  |  |
Ratio of consolidated EBITDDA to consolidated fixed charges |  |  |  |  |  |  |  | 3.5 |  |  |  |
Secured Debt |  |  |  |  |  |  |  | $ 709,900,000 |  |  |  |
Opco | $300 million floating rate revolving credit facility, due October 2017 |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Floating rate revolving credit facility |  | $ 300,000,000.0 |  |  |  |  |  | 300,000,000 |  |  |  |
Opco | $300 million floating rate revolving credit facility, due October 2017 | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility maturity date |  | Oct. 02, 2017 |  |  |  |  |  |  |  |  |  |
Opco | $300 million floating rate revolving credit facility, due August 2016 |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Floating rate revolving credit facility |  | $ 300,000,000.0 |  |  |  |  |  | $ 300,000,000 |  |  |  |
Opco | 8.38% senior notes, with semi-annual interest payments in March and September, with annual principal payments in March, maturing in March 2019 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Rate of senior notes |  |  |  |  |  |  |  | 8.38% |  |  |  |
Opco | 8.92% senior notes, with semi-annual interest payments in March and September, with scheduled principal payments beginning March 2014, maturing in March 2024 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Rate of senior notes |  |  |  |  |  |  |  | 8.92% |  |  |  |
Opco | Senior Notes |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Partnership leverage ratio |  |  |  |  |  |  |  | 3.75 |  |  |  |
Additional interest accrue |  |  |  |  |  |  |  | 2.00% |  |  |  |
Opco | Fiscal Quarter Ending on or Before March 31, 2016 [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Ratio of consolidated indebtedness to consolidated EBITDDA |  |  |  |  |  |  |  | 4.0 |  |  |  |
Opco | Fiscal Quarter Ending on or Before March 31, 2017 [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Ratio of consolidated indebtedness to consolidated EBITDDA |  |  |  |  |  |  |  | 3.75 |  |  |  |
Opco | Fiscal Quarter Ending on or After June 30, 2017 [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Ratio of consolidated indebtedness to consolidated EBITDDA |  |  |  |  |  |  |  | 3.5 |  |  |  |
Opco | Federal Funds Rate [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate (percent) |  | 0.50% |  |  |  |  |  | 0.50% |  |  |  |
Opco | London Interbank Offered Rate (LIBOR) [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate (percent) |  | 1.00% |  |  |  |  |  | 1.00% |  |  |  |
Opco | London Interbank Offered Rate (LIBOR) [Member] | Revolving Credit Facility Basis Spread Condition One [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Additional basis spread (percent) |  | 2.375% |  |  |  |  |  |  |  |  |  |
Opco | London Interbank Offered Rate (LIBOR) [Member] | Revolving Credit Facility Basis Spread Condition Two [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Additional basis spread (percent) |  | 3.375% |  |  |  |  |  |  |  |  |  |
Opco | London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member] | Revolving Credit Facility Basis Spread Condition One [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Additional basis spread (percent) |  |  |  |  |  |  |  | 2.50% |  |  |  |
Opco | London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member] | Revolving Credit Facility Basis Spread Condition Two [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Additional basis spread (percent) |  |  |  |  |  |  |  | 3.50% |  |  |  |
Opco | London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member] | Revolving Credit Facility Basis Spread Condition One [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Additional basis spread (percent) |  |  |  |  |  |  |  | 1.50% |  |  |  |
Opco | London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member] | Revolving Credit Facility Basis Spread Condition Two [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Additional basis spread (percent) |  |  |  |  |  |  |  | 2.50% |  |  |  |
NRP Oil and Gas |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Leverage ratio, maximum |  |  |  |  |  |  |  | 3.5 |  |  |  |
Current ratio, minimum |  |  |  |  |  |  |  | 1.0 |  |  |  |
NRP Oil and Gas | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Floating rate revolving credit facility |  |  |  |  |  |  |  |  |  |  | $ 105,000,000.0 |
Repayment of principal amount |  |  |  |  |  |  |  | $ 25,000,000 |  |  |  |
Weighted average interest rate for the debt outstanding (percent) |  |  |  |  |  | 2.37% |  | 2.50% |  |  |  |
Borrowings outstanding |  |  |  |  |  | $ 110,000,000 |  | $ 85,000,000 |  |  |  |
Term of credit facility |  |  |  |  | 5 years |  |  |  |  |  |  |
Senior secured revolving credit facility |  |  |  |  | $ 100,000,000 |  |  |  |  |  |  |
Maximum increase in aggregate commitment |  |  |  |  |  |  |  |  |  | $ 88,000,000.0 | $ 105,000,000.0 | $ 137,000,000.0
Debt Instrument maturities date |  |  |  |  |  |  |  | 2019-11 |  |  |  |
Leverage ratio, maximum |  |  |  |  |  |  |  | 3.5 |  |  |  |
NRP Oil and Gas | Amended On November 2014 [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Maximum increase in aggregate commitment |  |  |  |  |  |  |  |  |  |  |  | $ 500,000,000
NRP Oil and Gas | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Commitment fee on the unused portion of the borrowing base under the credit facility (percent) |  |  |  |  |  |  |  | 0.50% |  |  |  |
NRP Oil and Gas | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Commitment fee on the unused portion of the borrowing base under the credit facility (percent) |  |  |  |  |  |  |  | 0.375% |  |  |  |
NRP Oil and Gas | Federal Funds Rate [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Basis spread on variable rate (percent) |  |  |  |  |  |  |  | 0.50% |  |  |  |
NRP Oil and Gas | London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member] | Revolving Credit Facility Basis Spread Condition One [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Additional basis spread (percent) |  |  |  |  |  |  |  | 1.50% |  |  |  |
NRP Oil and Gas | London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member] | Revolving Credit Facility Basis Spread Condition Two [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Additional basis spread (percent) |  |  |  |  |  |  |  | 2.50% |  |  |  |
NRP Oil and Gas | London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member] | Revolving Credit Facility Basis Spread Condition One [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Additional basis spread (percent) |  |  |  |  |  |  |  | 0.50% |  |  |  |
NRP Oil and Gas | London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member] | Revolving Credit Facility Basis Spread Condition Two [Member] | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Additional basis spread (percent) |  |  |  |  |  |  |  | 1.50% |  |  |  |

X
- Definition Debt Covenant Ratio Of Consolidated Funded Indebtedness To Consolidated Earnings Before Interest Taxes Depreciation Amortizations And Other Items Allowed Per Credit Agreement Denominator + References No definition available. + Details
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- Definition Percentage price of original principal amount of debt at which debt can be redeemed by the issuer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph e -URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823 + Details
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 20, 22 -Article 5 + Details
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- Definition The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer. + References No definition available. + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Date the credit facility terminates, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility. + References No definition available. + Details
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- Definition The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585 + Details
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- Definition Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3291-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(f)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
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- Definition Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 20, 22 -Article 5 + Details
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