OTHER ASSETS (Details) - 10Q (USD $)	Mar. 31, 2015	Dec. 31, 2014
OTHER ASSETS
Security deposits	$ 2,146,000us-gaap_SecurityDeposit	$ 2,090,000us-gaap_SecurityDeposit
Escrow deposits to fund future capital improvements	273,000	253,000
Intangible assets, net of accumulated amortization	41,000us-gaap_FiniteLivedIntangibleAssetsNet	49,000us-gaap_FiniteLivedIntangibleAssetsNet
Accumulated amortization on intangible assets in connection with the acquisition of Windsor Green	1,711,000	1,703,000
Financing fees, net	1,681,000nen_FinancingAndLeasingFeesNet	1,736,000nen_FinancingAndLeasingFeesNet
Accumulated amortization on financing and leasing fees	$ 668,000	$ 613,000

Represents the accumulated amortization on financing and leasing fees.

No definition available.

Name:	nen_AccumulatedAmortizationOnFinancingAndLeasingFees
Namespace Prefix:	nen_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Restricted cash held in escrow to fund future capital improvements.

+ References

No definition available.

+ Details

Name:	nen_EscrowDepositToFundCapitalImprovements
Namespace Prefix:	nen_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the financing and leasing fees, net of accumulated amortization.

+ References

No definition available.

+ Details

Name:	nen_FinancingAndLeasingFeesNet
Namespace Prefix:	nen_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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

- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of an asset, typically cash, provided to a counterparty to provide certain assurance of performance by the entity pursuant to the terms of a written or oral agreement, such as a lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.8,17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_SecurityDeposit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant