v3.21.2

CONSOLIDATED STATEMENTS OF PARTNERS' EQUITY AND MEZZANINE EQUITY (Parenthetical) - $ / shares | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Common Limited Partner [Member] |  |  |  |
Cash distributions paid, per unit | $ 0.40 | $ 0.40 | $ 1.20 | $ 1.40

X
- Definition Per unit of ownership amount of cash distributions paid to unit-holder of a limited partnership (LP). + 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_DistributionMadeToLimitedPartnerDistributionsPaidPerUnit
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_PartnerTypeOfPartnersCapitalAccountAxis=ns_CommonLimitedPartnerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |