Represents that additional interest rate margin on a debt instrument.

No definition available.

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Period Type:	duration

- Definition

Represents the ratio of consolidated adjusted earnings before interest, taxes, depreciation and amortization to interest expense, which is necessary to be maintained under the terms of the senior credit facilities' covenants.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Represents the ratio of consolidated total debt to consolidated adjusted earnings before, interest, taxes, depreciation and amortization allowed under the terms of the senior credit facilities' covenants.

+ References

No definition available.

+ Details

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Namespace Prefix:	nen_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the debt ratio allowed under the terms of the senior credit facilities' covenants.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Length of extension of credit line, 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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Balance Type:	na
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- Definition

Period of line of credit facility extension, 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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Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity during the modifications period under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

No definition available.

+ Details

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

- Definition

Represents the level of tangible net worth required to maintain.

+ References

No definition available.

+ Details

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

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the fee that accompanies borrowing money under the debt instrument.

+ References

+ Details

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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

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Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

The number of real estate properties 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

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow from the repayment of a long-term debt instrument issued, secured by a first mortgage deed of trust, containing a pledge of real property. The lender has the highest claim on the property in case of default.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

+ Details

Name:	us-gaap_RepaymentsOfFirstMortgageBond
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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SUBSEQUENT EVENTS (Details)					1 Months Ended	9 Months Ended
SUBSEQUENT EVENTS (Details)	Oct. 29, 2021 USD ($)	Oct. 28, 2021	Oct. 29, 2020 USD ($)	Jul. 31, 2014 USD ($) item	Oct. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Aug. 31, 2017 USD ($)
Subsequent events
Payment of debt						$ 1,704,743	$ 1,668,702
Minimum
Subsequent events
Debt service coverage ratio						1.6
Tangible Net Worth						$ 150,000,000
Maximum
Subsequent events
Leverage ratio						65.00%
Line of Credit
Subsequent events
Term of debt				3 years
Line of Credit Facility, Extension Period			1 year
Maximum borrowings				$ 25,000,000
Amount of refinancing costs			$ 37,500					$ 128,000
Number of properties in which borrowing amount collateralized \| item				23
Credit line balance						$ 17,000,000
Line of Credit \| Subsequent event
Subsequent events
Line of Credit Facility, Extension Period	3 years
Line of credit extension term	3 years
Maximum borrowings	$ 25,000,000
Maximum borrowings during modification period	17,000,000
Amount of refinancing costs	$ 125,000
Line of Credit \| Federal Funds Rate
Subsequent events
Variable interest rate spread				0.50%
Line of Credit \| LIBOR
Subsequent events
Additional applicable margin rate				2.50%
Variable interest rate spread				1.00%
Line of Credit \| LIBOR \| Subsequent event
Subsequent events
Variable interest rate spread	300.00%	350.00%
Master Credit Facility [Member] \| Subsequent event
Subsequent events
Maximum borrowings					$ 149,000,000
Amount of refinancing costs					270,000
Payment of debt					$ 65,000,000
Number of properties in which borrowing amount collateralized					11
Mortgage prepayment penalties					$ 5,000,000
Credit line balance					$ 79,000,000
Current covenants \| Line of Credit \| Subsequent event
Subsequent events
Debt service coverage ratio	1.60
Tangible Net Worth	$ 200,000,000
Leverage ratio	65.00%
Debt yield	9.50%
Revised covenants inplace until September 30, 2022 \| Line of Credit \| Subsequent event
Subsequent events
Debt service coverage ratio	1.35
Tangible Net Worth	$ 175,000,000
Leverage ratio	70.00%
Debt yield	8.50%
Revised Covenants in place until December 31, 2022 \| Line of Credit \| Subsequent event
Subsequent events
Debt yield	9.00%