v3.8.0.1

PARTNERS' EQUITY Narrative 1 (Details)	3 Months Ended
	Mar. 31, 2018
Class of Stock [Line Items]
Percent of available cash distributed	100.00%
Number of days within which distribution Is paid to common unitholder and general partner	45
Series A Preferred Limited Partner [Member]
Class of Stock [Line Items]
Preferred units distribution percentage	8.50%
Series B Preferred Limited Partner [Member]
Class of Stock [Line Items]
Preferred units distribution percentage	7.625%
Series C Preferred Limited Partner [Member]
Class of Stock [Line Items]
Preferred units distribution percentage	9.00%

X

- Definition

Number of days within which distribution must be paid to common unitholders and the general partner after end of quarter (per the terms of the partnership agreement).

+ References

No definition available.

+ Details

Name:	ns_NumberofDaysWithinWhichDistributionIsPaidToCommonUnitholderAndGeneralPartner
Namespace Prefix:	ns_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Percent of available cash distributed to partners (per the terms of the partnership agreement).

+ 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

The percentage rate used to calculate dividend payments on preferred stock.

+ References

No definition available.

+ Details

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

X

- Details

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Namespace Prefix:
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Balance Type:
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X

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

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Namespace Prefix:
Data Type:	na
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