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Represents the number of partnerships which are investing in commercial properties.

No definition available.

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The number of units in a real estate property refinanced.

No definition available.

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Represents the number of units retained for long-term investment.

No definition available.

Name:	nen_NumberOfUnitsInRealEstatePropertyRetainedForLongTermInvestment
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Represents the number of units sold.

No definition available.

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Represents the number of units unsold by the entity.

No definition available.

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Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The number of units in a real estate property owned as of the balance sheet date.

No definition available.

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Total distributions to each class of partners (i.e., general, limited and preferred partners).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Balance Type:	credit
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Name:	dei_LegalEntityAxis=nen_HamiltonBayApartmentsLLCMember
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Name:	dei_LegalEntityAxis=nen_Franklin345LLCMember
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Data Type:	na
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Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_MortgagesMember
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Data Type:	na
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Name:	us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=nen_CondominiumRealEstateMember
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Data Type:	na
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Name:	us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=us-gaap_ResidentialRealEstateMember
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Name:	us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=us-gaap_CommercialRealEstateMember
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Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
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