Label	Element	Value
Hamilton Bay L L C [Member]
Partners' Capital Account, Contributions	us-gaap_PartnersCapitalAccountContributions	$ 660,000
Hamilton Essex81 L L C [Member]
Partners' Capital Account, Contributions	us-gaap_PartnersCapitalAccountContributions	100,000
Partners' Capital Account, Distributions	us-gaap_PartnersCapitalAccountDistributions	978,193
Hamilton Essex81 L L C [Member] \| Maximum [Member]
Equity Method Investments, Carrying Value	nen_EquityMethodInvestmentsCarryingValue	0
Hamilton Essex Development L L C [Member]
Partners' Capital Account, Contributions	us-gaap_PartnersCapitalAccountContributions	$ 978,193
Mortgage2.18 Percent Plus Libor September2015 [Member] \| Hamilton Essex81 L L C [Member] \| Hamilton Essex81 L L C [Member]
Debt Instrument, Term	us-gaap_DebtInstrumentTerm	10 years

Represents the carrying value of equity method investment as of the balance sheet date.

No definition available.

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

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Total contributions made by each class of partners (i.e., general, limited and preferred partners).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

+ Details

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

- Definition

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

+ References

+ Details

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

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
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- Details

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Namespace Prefix:
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- Details

Name:	us-gaap_DebtInstrumentAxis=nen_Mortgage2.18PercentPlusLiborSeptember2015Member
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- Details

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