Debt instrument additional variable interest rate.

No definition available.

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- Definition

Debt Instrument, Covenant, Maximum Leverage Ratio

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Percentage of Principal Eligible for Redemption

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Debt instrument redemption price percentage of principal remaining after redemption.

+ References

No definition available.

+ Details

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- Definition

Partnership leverage ratio.

+ References

No definition available.

+ Details

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120400017&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120398452&loc=d3e534808-122878

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of assets pledged to secure a debt instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=123599511&loc=d3e64711-112823

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120391452&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The distribution amount per share for all classes of units.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB TOPIC 4.F)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187171-122770

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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
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3291-108585

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Debt, Net - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Debt Instrument [Line Items]
Principal balance	$ 458,819		$ 477,880
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%
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		300,000
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		0
Line of Credit Facility, Remaining Borrowing Capacity	$ 100,000		100,000
Distribution per share (in dollars per share)	$ 0.45
Ratio Of Ebitda to consolidated fixed charges	3.5
Collateral carrying amount	$ 352,100		364,500
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	$ 12,035		16,047
Rate of senior notes	8.92%
Opco \| Senior Notes
Debt Instrument [Line Items]
Principal balance	$ 158,819		$ 177,880
Principal payments on its senior notes	$ 19,100	$ 25,800
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%