v3.10.0.1

PARTNERS' EQUITY Narrative 3 (Details)	6 Months Ended
	Jun. 30, 2018
Class of Stock [Line Items]
General partner ownership interest	2.00%
Common Limited Partner [Member]
Class of Stock [Line Items]
Common unitholders ownership interest	98.00%
General Partner [Member]
Class of Stock [Line Items]
General partner ownership interest	2.00%

X

- Definition

The general partner ownership interest (ownership percentage) in the limited partnership. Excludes other ownership interests held by the general partner in the limited partnership.

+ References

No definition available.

+ Details

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Namespace Prefix:	ns_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

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

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

X

- Definition

Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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X

- Details

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Namespace Prefix:
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X

- Details

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Namespace Prefix:
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