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

No definition available.

Name:	nen_PartnersCapitalAccountDepositoryReceiptsTreasury
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Represents the average price at which depository receipts are repurchased under the equity repurchase program.

No definition available.

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

No definition available.

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

No definition available.

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Represents the fixed distribution percentages of the holders of units based on which the entity is required to purchase the proportionate number of specific units with every purchase of depository receipts.

No definition available.

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Represents the period over which the entity is permitted to purchase its depository receipts.

No definition available.

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Represents the number of treasury units outstanding as on the balance sheet date.

No definition available.

Name:	nen_PartnersCapitalAccountTreasuryUnitsIssued
Namespace Prefix:	nen_
Data Type:	xbrli:sharesItemType
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Represents the average price at which units are repurchased under the equity repurchase program.

No definition available.

Name:	nen_PartnersCapitalAccountUnitsTreasuryAverageRepurchasePricePerUnit
Namespace Prefix:	nen_
Data Type:	us-types:perUnitItemType
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Value of units that were previously issued and have been repurchased during the year.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6828210&loc=d3e70191-108054

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Units that were previously issued and have been repurchased during the year.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB TOPIC 4.F)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187171-122770

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