The number of real estate properties sold as of the balance sheet date.

No definition available.

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Namespace Prefix:	nen_
Data Type:	xbrli:integerItemType
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Period Type:	instant

- Definition

Represents the number of depository receipts repurchased under the equity repurchase program.

+ References

No definition available.

+ Details

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Namespace Prefix:	nen_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the quarterly distributions per depository receipt.

+ References

No definition available.

+ Details

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Namespace Prefix:	nen_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the quarterly distributions per unit.

+ References

No definition available.

+ Details

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Namespace Prefix:	nen_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 12
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-12

+ Details

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

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481674/830-30-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

+ Details

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

- Details

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

- Details

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=nen_CommercialOfficeBuildingsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
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SUBSEQUENT EVENTS (Details)		1 Months Ended	3 Months Ended	223 Months Ended
SUBSEQUENT EVENTS (Details)	Jan. 28, 2026 USD ($) building	May 08, 2026 shares	Mar. 31, 2026 USD ($) $ / shares	Mar. 31, 2026 $ / shares shares	May 07, 2026 $ / shares
Subsequent events
Quarterly distributions per depositary receipt (in dollars per receipt)			$ 0.4	$ 0.4
Number of depository receipts repurchased \| shares				1,561,062
Properties sold \| $			$ 2,438,747
Commercial property \| Commercial Office Buildings
Subsequent events
Number of real estate properties sold \| building	2
Properties sold \| $	$ 2,600,000
Subsequent Event
Subsequent events
Quarterly distribution (per unit)					$ 12
Quarterly distributions per depositary receipt (in dollars per receipt)					$ 0.4
Number of depository receipts repurchased \| shares		813