XML 79 R50.htm IDEA: XBRL DOCUMENT v3.3.1.900

Acquisitions - Additional Information (Detail) $ in Thousands			3 Months Ended		12 Months Ended
	Nov. 12, 2014 USD ($)	Oct. 01, 2014 USD ($) quarry plant mine terminal	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2015 USD ($) quarry plant terminal	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Aug. 31, 2013 USD ($)
VantaCore Partners LP
Business Acquisition [Line Items]
Aggregate acquisition cost		$ 200,582
Number of hard rock quarries | quarry		3			4
Number of sand and gravel plants | plant		6			6
Number of asphalt plants | plant		2			2
Number of underground limestone mine | mine		1
Number of marine terminal | terminal		1			2
Increase in plant and equipment				$ 22,500
Increase to mineral rights and intangible assets			$ 24,700
Acquisition related purchase price adjustments					$ (2,300)
Revenue from acquired entity						$ 42,100
Operating income from acquired entity						100
Transaction costs of acquisition						2,900
Purchase price allocation for assets acquired		$ 59,946
Sanish Field [Member]
Business Acquisition [Line Items]
Aggregate acquisition cost	$ 339,100
Revenue from acquired entity						12,800
Operating income from acquired entity						3,700
Transaction costs of acquisition						$ 1,800
Sundance Energy Inc [Member]
Business Acquisition [Line Items]
Purchase price allocation for assets acquired							$ 29,400
Abraxas Petroleum [Member]
Business Acquisition [Line Items]
Purchase price allocation for assets acquired								$ 38,000
Abraxas and Sundance [Member]
Business Acquisition [Line Items]
Operating income from acquired entity							2,500
Combined revenues							$ 5,400

X

- Definition

Business Acquisition Revenue Recorded During Period

+ References

No definition available.

+ Details

Name:	nrp_BusinessAcquisitionRevenueRecordedDuringPeriod
Namespace Prefix:	nrp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Business Combination, Pro Forma Information, Operating Income (Loss) of Acquiree since Acquisition Date, Actual

+ References

No definition available.

+ Details

Name:	nrp_BusinessCombinationProFormaInformationOperatingIncomeLossofAcquireesinceAcquisitionDateActual
Namespace Prefix:	nrp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Business combination provisional information initial accounting incomplete adjustment mineral rights and intangible assets

+ References

No definition available.

+ Details

Name:	nrp_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentMineralRightsAndIntangibleAssets
Namespace Prefix:	nrp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Business Combination, Provisional Information, Initial Accounting Incomplete, Asset Retirement Obligation

+ References

No definition available.

+ Details

Name:	nrp_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAssetRetirementObligation
Namespace Prefix:	nrp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Represents the number of asphalt plants.

+ References

No definition available.

+ Details

Name:	nrp_NumberOfAsphaltPlants
Namespace Prefix:	nrp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Represents the number of hard rock quarries.

+ References

No definition available.

+ Details

Name:	nrp_NumberOfHardRockQuarries
Namespace Prefix:	nrp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Represents the number of sand and gravel plants.

+ References

No definition available.

+ Details

Name:	nrp_NumberOfSandAndGravelPlants
Namespace Prefix:	nrp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Number of Marine Terminal

+ References

No definition available.

+ Details

Name:	nrp_NumberofMarineTerminal
Namespace Prefix:	nrp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Number of Underground Limestone Mine

+ References

No definition available.

+ Details

Name:	nrp_NumberofUndergroundLimestoneMine
Namespace Prefix:	nrp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- 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

Name:	us-gaap_BusinessAcquisitionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e1043-128460

+ Details

Name:	us-gaap_BusinessCombinationAcquisitionRelatedCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

+ Details

Name:	us-gaap_BusinessCombinationConsiderationTransferred1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

+ Details

Name:	us-gaap_BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to property, plant, and equipment acquired in connection with a business combination for which the initial accounting was incomplete.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1500-128463

+ Details

Name:	us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentPropertyPlantAndEquipment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=35744172&loc=d3e2207-128464

+ Details

Name:	us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

Name:	us-gaap_BusinessAcquisitionAxis=nrp_VantaCoreAcquisitionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_BusinessAcquisitionAxis=nrp_SanishFieldAcquisitionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_BusinessAcquisitionAxis=nrp_SundanceEnergyIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_BusinessAcquisitionAxis=nrp_AbraxasPetroleumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_BusinessAcquisitionAxis=nrp_AbraxasAndSundanceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: