Description of the calculation of undistributed net loss.

No definition available.

Name:	nmm_DescriptionLossAllocation
Namespace Prefix:	nmm_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of the distribution amount per unit for all classes of units.

+ References

No definition available.

+ Details

Name:	nmm_MinimumQuarterlyDistributionDescriptionPolicy
Namespace Prefix:	nmm_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

- Definition

Allocation of net income/ loss between each class of units.

+ References

No definition available.

+ Details

Name:	nmm_NetIncomeLossAllocationToEachClassUnit
Namespace Prefix:	nmm_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

+ Details

Name:	us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Per unit of ownership amount of cash distributions declared to unit-holder of a limited liability company (LLC).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

+ Details

Name:	us-gaap_DistributionMadeToLimitedLiabilityCompanyLLCMemberDistributionsDeclaredPerUnit
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of cash distribution paid to unit-holder of limited partnership (LP).

+ References

+ Details

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

- Definition

Date of record for distribution of cash or unit to limited partner of limited partnership (LP), in CCYY-MM-DD format.

+ References

+ Details

Name:	us-gaap_DistributionMadeToLimitedPartnerDateOfRecord
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Date of distribution for distribution of cash or unit to limited partner of limited partnership (LP), in CCYY-MM-DD format.

+ References

+ Details

Name:	us-gaap_DistributionMadeToLimitedPartnerDistributionDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

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

- Details

Name:	us-gaap_StatementClassOfStockAxis=nmm_LimitedSubordinatedPartnerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementClassOfStockAxis=us-gaap_GeneralPartnerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DistributionsMadeToMemberOrLimitedPartnerByDistributionTypeAxis=nmm_Installment4FY2018Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DistributionsMadeToMemberOrLimitedPartnerByDistributionTypeAxis=nmm_Installment1FY2019Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DistributionsMadeToMemberOrLimitedPartnerByDistributionTypeAxis=nmm_Installment2FY2019Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DistributionsMadeToMemberOrLimitedPartnerByDistributionTypeAxis=nmm_Installment3FY2019Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DistributionsMadeToMemberOrLimitedPartnerByDistributionTypeAxis=nmm_Installment4FY2019Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DistributionsMadeToMemberOrLimitedPartnerByDistributionTypeAxis=nmm_Installment1FY2020Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DistributionsMadeToMemberOrLimitedPartnerByDistributionTypeAxis=nmm_Installment2FY2020Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Cash Distributions and Earnings per Unit (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Distribution Made to Limited Partner [Line Items]
Description of the distribution amount per unit for all classes of units			The first 98% of the quarterly distribution is paid to all common unitholders. The incentive distributions rights (held by the General Partner) apply only after a minimum quarterly distribution of $6.0375.
Description of loss allocation			Net loss per unit undistributed is determined by taking the distributions in excess of net income and allocating between common units and general partner units on a 98%-2% basis.
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	140,191	235,669	140,191	235,669
Common and subordinated units
Distribution Made to Limited Partner [Line Items]
Net loss allocated to each class of unit	98.00%		98.00%
General Partner
Distribution Made to Limited Partner [Line Items]
Net loss allocated to each class of unit	2.00%		2.00%
Installment 4 - FY 2018
Distribution Made to Limited Partner [Line Items]
Cash distribution declared per unit			$ 0.30
Distribution date			Feb. 14, 2019
Date of record			Feb. 11, 2019
Aggregate amount of cash distributions paid			$ 3,458
Installment 1 - FY 2019
Distribution Made to Limited Partner [Line Items]
Cash distribution declared per unit			$ 0.30
Distribution date			May 14, 2019
Date of record			May 10, 2019
Aggregate amount of cash distributions paid			$ 3,364
Installment 2 - FY 2019
Distribution Made to Limited Partner [Line Items]
Cash distribution declared per unit			$ 0.30
Distribution date			Aug. 09, 2019
Date of record			Aug. 06, 2019
Aggregate amount of cash distributions paid			$ 3,364
Installment 3 - FY 2019
Distribution Made to Limited Partner [Line Items]
Cash distribution declared per unit			$ 0.30
Distribution date			Nov. 14, 2019
Date of record			Nov. 07, 2019
Aggregate amount of cash distributions paid			$ 3,364
Installment 4 - FY 2019
Distribution Made to Limited Partner [Line Items]
Cash distribution declared per unit			$ 0.30
Distribution date			Feb. 13, 2020
Date of record			Feb. 11, 2020
Aggregate amount of cash distributions paid			$ 3,366
Installment 1 - FY 2020
Distribution Made to Limited Partner [Line Items]
Cash distribution declared per unit			$ 0.30
Distribution date			May 14, 2020
Date of record			May 11, 2020
Aggregate amount of cash distributions paid			$ 3,365
Installment 2 - FY 2020
Distribution Made to Limited Partner [Line Items]
Cash distribution declared per unit			$ 0.05
Distribution date			Aug. 13, 2020
Date of record			Aug. 10, 2020
Aggregate amount of cash distributions paid			$ 561