CONSOLIDATED BALANCE SHEETS (USD $)	Mar. 31, 2015	Dec. 31, 2014
ASSETS
Rental Properties	$ 147,573,728us-gaap_RentalProperties	$ 149,116,084us-gaap_RentalProperties
Cash and Cash Equivalents	14,036,371	14,015,898
Rents Receivable	500,001us-gaap_AccountsReceivableNet	474,225us-gaap_AccountsReceivableNet
Real Estate Tax Escrows	343,485us-gaap_EscrowDeposit	340,341us-gaap_EscrowDeposit
Prepaid Expenses and Other Assets	3,270,191us-gaap_PrepaidExpenseAndOtherAssets	3,287,005us-gaap_PrepaidExpenseAndOtherAssets
Investments in Unconsolidated Joint Ventures	8,268,172us-gaap_EquityMethodInvestments	8,807,868us-gaap_EquityMethodInvestments
Financing and Leasing Fees	1,680,700nen_DeferredFinancingAndLeasingCostsNet	1,735,652nen_DeferredFinancingAndLeasingCostsNet
Total Assets	175,672,648us-gaap_Assets	177,777,073us-gaap_Assets
LIABILITIES AND PARTNERS' CAPITAL
Mortgage Notes Payable	196,038,642us-gaap_SecuredDebt	196,071,540us-gaap_SecuredDebt
Distribution and Loss in Excess of Investment in Unconsolidated Joint Venture	1,487,939	1,425,369
Accounts Payable and Accrued Expenses	2,684,390	3,099,117
Advance Rental Payments and Security Deposits	4,589,471us-gaap_CustomerAdvancesAndDeposits	4,548,729us-gaap_CustomerAdvancesAndDeposits
Total Liabilities	204,800,442us-gaap_Liabilities	205,144,755us-gaap_Liabilities
Commitments and Contingent Liabilities (Notes 3 and 9)
Partners' Capital 126,844 and 127,653 units outstanding in 2015 and 2014 respectively	(29,127,794)us-gaap_PartnersCapital	(27,367,682)us-gaap_PartnersCapital
Total Liabilities and Partners' Capital	$ 175,672,648	$ 177,777,073

This element represents the deferred financing and leasing cost incurred by the entity during the reporting period.

No definition available.

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Represents the share of partners capital in distribution and loss in excess of investment in unconsolidated joint venture.

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Sum of the carrying values as of the balance sheet date of obligations incurred through that date, including liabilities incurred and payable to vendors for goods and services received, taxes, interest, rent and utilities, compensation costs, payroll taxes and fringe benefits (other than pension and postretirement obligations), contractual rights and obligations, and statutory obligations.

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For an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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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.

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Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur.

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Refundable consideration, usually cash, held by the entity pending satisfactory completion of the entity's obligations or pending the closing of a contract.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

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Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

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Amount of liabilities and equity items, including the portion of equity attributable to noncontrolling interests, if any.

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The amount of ownership interest of different classes of partners in limited partnership.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets.

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Carrying amount of income producing properties held for rental.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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