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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets. Includes expense included in continuing and discontinued operations.

No definition available.

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The increase (decrease) in accounts payable related to capital expenditures that have been incurred but not yet paid.

No definition available.

Name:	ns_IncreaseDecreaseinAccountsPayableRelatedtoCapitalExpenditures
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No definition available.

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Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Glossary Cash Equivalents
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-Name Accounting Standards Codification
-Topic 210
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-Subparagraph (SX 210.5-02.1)
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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of increase (decrease) from the effect of exchange rate changes on cash and cash equivalent balances held in foreign currencies.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
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This item represents disclosure of the amount of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporation; these investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
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-Subparagraph (SX 210.7-04(10))
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-Name Accounting Standards Codification
-Topic 225
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-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(12))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Name:	us-gaap_EquityMethodInvestmentDividendsOrDistributions
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
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-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2443-110228

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Period Type:	duration

The increase (decrease) in cash during the period due to the net increase or decrease in book overdrafts.

No definition available.

Name:	us-gaap_IncreaseDecreaseInBookOverdrafts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The increase (decrease) during the reporting period of all assets and liabilities used in operating activities.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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Name:	us-gaap_IncreaseDecreaseInOperatingCapital
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Data Type:	xbrli:monetaryItemType
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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

Name:	us-gaap_NetCashProvidedByUsedInFinancingActivities
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Balance Type:	debit
Period Type:	duration

No definition available.

Name:	us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract
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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

Name:	us-gaap_NetCashProvidedByUsedInInvestingActivities
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Balance Type:	debit
Period Type:	duration

No definition available.

Name:	us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract
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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Name:	us-gaap_NetCashProvidedByUsedInOperatingActivities
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Period Type:	duration

No definition available.

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

Amount of income (expense) included in net income that results in no cash inflow (outflow), classified as other.

Name:	us-gaap_OtherNoncashIncomeExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

Name:	us-gaap_PaymentsOfDividends
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Period Type:	duration

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6516133

Name:	us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired
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Data Type:	xbrli:monetaryItemType
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Amount of cash outflow for the purchase of or improvements to tangible or intangible assets, used to produce goods or deliver services, classified as other.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Name:	us-gaap_PaymentsToAcquireOtherProductiveAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Name:	us-gaap_PaymentsToAcquireProductiveAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The cash inflow from the issuance of common limited partners units during the period.

Name:	us-gaap_ProceedsFromIssuanceOfCommonLimitedPartnersUnits
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Name:	us-gaap_ProceedsFromIssuanceOfLongTermDebt
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The cash inflow from the capital received in cash from a partner in a partnership during the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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-Glossary Financing Activities
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Name:	us-gaap_ProceedsFromPartnershipContribution
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount of cash inflow (outflow) from financing activities classified as other.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Glossary Financing Activities
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Name:	us-gaap_ProceedsFromPaymentsForOtherFinancingActivities
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Balance Type:	debit
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The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=6516133

Name:	us-gaap_ProceedsFromSaleOfProductiveAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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The cash inflow from a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

Name:	us-gaap_ProceedsFromShortTermDebt
Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	duration

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
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-Paragraph 4K
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=68079674&loc=SL4569616-111683

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=64809438&loc=SL4573702-111684

Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Paragraph 4J
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-Paragraph 1A
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Name:	us-gaap_ProfitLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Name:	us-gaap_RepaymentsOfLongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

The cash outflow for a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

Name:	us-gaap_RepaymentsOfShortTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.