Name:	nen_ManagementFees
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The aggregate costs of keeping the property in good condition but that do not appreciably prolong the life or increase the value of the property.

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Total costs of sales and operating expenses for the period.

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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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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No definition available.

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Revenue from facility or amenity membership and its operations during the reporting period.

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of the cost of borrowed funds accounted for as interest expense.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

No definition available.

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Period Type:	duration

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Net Income
-URI http://asc.fasb.org/extlink&oid=51831255

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-Topic 944
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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-Subparagraph (SX 210.5-03(20))
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Per unit of ownership amount after tax of income (loss) available to outstanding limited partnership (LP) unit-holder.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	na
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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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No definition available.

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No definition available.

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Period Type:	duration

The net result for the period of deducting operating expenses from operating revenues.

No definition available.

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The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Other costs incurred during the reporting period related to other revenue generating activities.

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Balance Type:	debit
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The aggregate total of real estate taxes and insurance expense.

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Data Type:	xbrli:monetaryItemType
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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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No definition available.

Name:	us-gaap_RevenuesAbstract
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Data Type:	xbrli:stringItemType
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Period Type:	duration

Weighted average number of limited partnership units outstanding determined by relating the portion of time within a reporting period that limited partnership units have been outstanding to the total time in that period.