Debt instrument additional variable interest rate.

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- Definition

Debt Instrument, Covenant, Maximum Leverage Ratio

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No definition available.

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- Definition

Debt Instrument, Percentage of Principal Eligible for Redemption

+ References

No definition available.

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- Definition

Debt instrument redemption price at change of control event as percentage of principal amount.

+ References

No definition available.

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- Definition

Debt instrument redemption price percentage of principal remaining after redemption.

+ References

No definition available.

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- Definition

Partnership leverage ratio.

+ References

No definition available.

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- Definition

Ratio of EBITDA to consolidated fixed charges.

+ References

No definition available.

+ Details

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Amount of assets pledged to secure a debt instrument.

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- Definition

The average effective interest rate during the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ 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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

The distribution amount per share for all classes of units.

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-Publisher FASB
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- Definition

The net cash inflow or outflow for borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 3
-Subparagraph (SX 210.12-04(a))
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- Definition

The excess of the (1) fair value of consideration transferred to the holders of a security in excess of (2) the carrying amount of the security reported on the registrant's balance sheet, which will be deducted from net earnings to derive net earnings available to common shareholders. This amount is generally an adjustment considered in the computation of earnings per share.

+ References

No definition available.

+ Details

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Debt, Net - Additional Information (Detail)	3 Months Ended	9 Months Ended
Debt, Net - Additional Information (Detail)	Sep. 30, 2018	Sep. 30, 2019 USD ($) $ / shares	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Debt Instrument [Line Items]
Principal balance		$ 544,390,000		$ 687,138,000
Redemption premium		18,100,000
Write off of Deferred Debt Issuance Cost		$ 10,400,000
9.125% senior notes, with semi-annual interest payments in June and December, maturing June 2025 \| Senior Notes
Debt Instrument [Line Items]
Rate of senior notes		9.125%
Percentage of principal eligible for redemption		35.00%
Redemption price percentage of principal remaining after redemption		65.00%
Redemption price at change of control event as percentage of principal amount		101.00%
10.5% senior notes, with semi-annual interest payments in March and September, maturing March 2022 \| Senior Notes
Debt Instrument [Line Items]
Redemption percentage of principal		105.25%
Principal payments on its senior notes		$ 76,100,000
NRP LP \| 9.125% senior notes, with semi-annual interest payments in June and December, maturing June 2025
Debt Instrument [Line Items]
Principal balance		$ 300,000,000		0
Rate of senior notes		9.125%
Opco \| Floating Rate Revolving Credit Facility Due April Two Thousand Twenty Three
Debt Instrument [Line Items]
Principal balance		$ 0
Lender commitments under Opco credit facility		$ 100,000,000
Distribution per share (in dollars per share) \| $ / shares		$ 0.45
Ratio Of Ebitda to consolidated fixed charges		3.5
Weighted average interest rate	6.34%		6.18%
Collateral carrying amount		$ 541,500,000		548,900,000
Floating rate revolving credit facility		100,000,000
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
Debt Instrument [Line Items]
Principal balance		$ 20,059,000		27,185,000
Rate of senior notes		8.92%
Opco \| Senior Notes
Debt Instrument [Line Items]
Principal balance		$ 244,390,000		$ 341,500,000
Principal payments on its senior notes		97,100,000	$ 55,700,000
Pre-payment of Senior Notes		$ 49,300,000
Partnership leverage ratio		3.75
Additional interest accrue		2.00%
Dividend at or Below $0.45 per Share \| Opco \| Floating Rate Revolving Credit Facility Due April Two Thousand Twenty Three
Debt Instrument [Line Items]
Maximum leverage ratio		4.0
Dividend Above $0.45 per Share \| Opco \| Floating Rate Revolving Credit Facility Due April Two Thousand Twenty Three
Debt Instrument [Line Items]
Maximum leverage ratio		3.0
Debt Instrument, Redemption, Period Two \| 9.125% senior notes, with semi-annual interest payments in June and December, maturing June 2025 \| Senior Notes
Debt Instrument [Line Items]
Redemption percentage of principal		104.563%
Debt Instrument, Redemption, Period Three \| 9.125% senior notes, with semi-annual interest payments in June and December, maturing June 2025 \| Senior Notes
Debt Instrument [Line Items]
Redemption percentage of principal		102.281%
Debt Instrument, Redemption, Period Four \| 9.125% senior notes, with semi-annual interest payments in June and December, maturing June 2025 \| Senior Notes
Debt Instrument [Line Items]
Redemption percentage of principal		100.00%
Debt Instrument, Redemption, Period One \| 9.125% senior notes, with semi-annual interest payments in June and December, maturing June 2025 \| Senior Notes
Debt Instrument [Line Items]
Redemption percentage of principal		109.125%