v2.4.0.6

ACQUISITIONS AND DISPOSITIONS Narrative 1 (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011 San Antonio Refinery Acquisition	Dec. 31, 2011 Turkey Acquisition	Dec. 31, 2010 Asphalt Holdings Inc.
Business Acquisition [Line Items]
Effective date of acquisition	April 19, 2011	February 9, 2011	May 21, 2010
Percentage acquired		75.00%
Purchase price of acquired entity	$ 62.0	$ 57.0	$ 53.3
Acquired number of terminals		two	three
Acquired refining capacity (in barrels per day)	14,500
Acquired storage capacity (in barrels)	400,000	1,300,000	1,800,000
Ownership percentage held by noncontrolling owners		25.00%

X

- Definition

Number of terminal or storage facilities acquired in the business combination.

+ References

No definition available.

+ Details

Name:	ns_AcquiredNumberOfTerminals
Namespace Prefix:	ns_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Refining capacity of refinery acquired in the business combination, in barrels per day.

+ References

No definition available.

+ Details

Name:	ns_AcquiredRefiningCapacity
Namespace Prefix:	ns_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Aggregate storage capacity of tanks acquired in the business combination, in barrels.

+ References

No definition available.

+ Details

Name:	ns_AcquiredStorageCapacity
Namespace Prefix:	ns_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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

X

- Definition

Month, date and year in which the acquirer obtains control of the acquiree.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6909708&loc=d3e848-128460



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6909870&loc=d3e1392-128463



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 3

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6909708&loc=d3e845-128460



Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 10, 11

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Acquisition Date

-URI http://asc.fasb.org/extlink&oid=6919109

+ Details

Name:	us-gaap_BusinessAcquisitionEffectiveDateOfAcquisition
Namespace Prefix:	us-gaap_
Data Type:	us-types:dateStringItemType
Balance Type:	na
Period Type:	duration

X

- Details

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

X

- Definition

Percentage of voting equity interests acquired in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6909870&loc=d3e1392-128463

+ Details

Name:	us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant