v3.10.0.1

REVENUE FROM CONTRACTS WITH CUSTOMERS Narrative 2 (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 | Jun. 30, 2018 | Sep. 30, 2018
Additions to contract liability |  |  | $ 64,492
Revenue recognized due to change in contract liability |  | $ 9,000 |
Unnamed Customer [Member] |  |  |
Additions to contract liability | $ 37,500 |  |
Additions to other current assets | $ 37,500 |  |

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- Definition Contract with Customer, Liability, Additions + References No definition available. + Details
Name: | ns_ContractwithCustomerLiabilityAdditions
Namespace Prefix: | ns_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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- Definition Amount of revenue recognized arising from contract liability from change in timeframe for performance obligation to be satisfied. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130551-203045 + Details
Name: | us-gaap_ContractWithCustomerLiabilityChangeInTimeframePerformanceObligationSatisfiedRevenueRecognized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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- Definition Amount of increase (decrease) in current assets classified as other. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details
Name: | us-gaap_IncreaseDecreaseInOtherCurrentAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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- Details
Name: | srt_MajorCustomersAxis=ns_UnnamedCustomerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |