Represents the closing costs associated with the transaction.

No definition available.

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- Definition

Represents the carrying value of the property.

+ References

No definition available.

+ Details

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- Definition

Represents the penalty amount for early repayment of debt.

+ References

No definition available.

+ Details

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Namespace Prefix:	nen_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Represents the aggregate purchase price of real estate properties acquired by the entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	nen_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the aggregate sales price of real estate properties sold by the entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	nen_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- 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

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The number of units in a real estate property owned as of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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RENTAL PROPERTIES (Hamilton Green) (Details)			1 Months Ended	12 Months Ended
RENTAL PROPERTIES (Hamilton Green) (Details)	Aug. 03, 2016 USD ($)	Aug. 31, 2004 USD ($)	Aug. 31, 2014 USD ($)	Dec. 31, 2017 USD ($) item	Dec. 31, 2016 USD ($) item	Dec. 31, 2018 item
RENTAL PROPERTIES
Number of units \| item				1,033	1,033	1,033
Gain on sale of real estate					$ (104,443)
Hamilton Green
RENTAL PROPERTIES
Sales price of real estate properties	$ 1,000,000				$ 1,000,000
Gain on sale of real estate	103,793
Closing costs	227,663
Cost basis of the property	668,544
Prepayment penalty	$ 187,905
Hamilton on Main Apts
RENTAL PROPERTIES
Purchase price of real estate properties		$ 56,000,000
Mortgage, 4.34%, August 2014 \| Hamilton on Main Apts
RENTAL PROPERTIES
Closing costs				$ 161,000
Term of debt			10 years
Mortgage amount			$ 16,900,000
Interest rate (as a percent)			4.34%