Represents the amount of quarterly fee for asset management consulting services.

No definition available.

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- Definition

Represents the amount of principal to be repaid upon notice as per the request of the lender.

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No definition available.

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Represents the period of notice to be served in order to demand earlier payment of debt in whole or in part.

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No definition available.

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This element represents the expenses incurred for attendance and participation in advisory committee meeting.

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Represents the expenses incurred for attendance and participation in Advisory Committee meeting.

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Represents the number of limited partnerships and limited liability companies in which the entity has made investments.

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No definition available.

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This element represents the amount of management fee incurred for payment to a management company during the reporting period.

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Represents the number of Advisory Committee meeting held during the reporting period.

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Represents the number of Audit Committee meeting held during the period.

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Represents the number of employees other than the President having an ownership interest.

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Represents the amount charged for bookkeeping and accounting services as included in administrative expenses.

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Represents the charge against earnings towards management fees associate with the services provided by related party.

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Represents the management fees expressed as a percentage of Linewt.

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Represents the management fee expressed as a percentage of rental revenues from properties owned.

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Represents the number of employees who perform accounting and bookkeeping functions.

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Represents the amount reimbursed to related party for transfer of employee payroll.

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Represents the amount of rental commission expense charged against the earnings during the period.

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The aggregate costs related to asset management during the reporting period.

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-SubTopic 10

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-Paragraph 2

-Subparagraph (SX 210.5-03.2(d))

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The aggregate costs of keeping the property in good condition but that do not appreciably prolong the life or increase the value of the property.

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

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-Publisher SEC

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Amount of the required periodic payments applied to principal.

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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.

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The amount of the cost recognized during the period for defined contribution plans.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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The amount of cash paid for interest during the period.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

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Amount of transactions with related party during the financial reporting period.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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RELATED PARTY TRANSACTIONS (Details) (USD $)	12 Months Ended			0 Months Ended					1 Months Ended		3 Months Ended
RELATED PARTY TRANSACTIONS (Details) (USD $)	Dec. 31, 2014 item	Dec. 31, 2013	Dec. 31, 2012	Dec. 15, 2011	Oct. 02, 2011	Aug. 02, 2011	Aug. 17, 2010	Oct. 28, 2009	Apr. 30, 2012	Feb. 29, 2012	Dec. 31, 2010	Dec. 31, 2011
RELATED PARTY TRANSACTIONS
Management fee as percentage of gross receipts rental revenue	4.00%
Management fee as a percentage of gross receipts rental revenue of Linewt, LLC	3.00%
Management fees of related party	$ 1,745,000	$ 1,578,000	$ 1,447,000
Repairs and maintenance	6,608,290	5,815,264	5,075,037
Administrative expense	2,206,483us-gaap_GeneralAndAdministrativeExpense	2,116,527us-gaap_GeneralAndAdministrativeExpense	1,813,150us-gaap_GeneralAndAdministrativeExpense
Management fee	1,744,849nen_ManagementFees	1,570,158nen_ManagementFees	1,428,052nen_ManagementFees
Number of limited partnerships and limited liability companies in which the entity has invested	9
Outstanding amount of mortgage loan	196,071,540us-gaap_SecuredDebt	198,520,478us-gaap_SecuredDebt
Interest paid	8,791,000us-gaap_InterestPaid	8,062,000us-gaap_InterestPaid	7,776,000us-gaap_InterestPaid
Number of advisory committee meetings	6
Number of audit committee meetings held	4nen_NumberOfAuditCommitteeMeetingHeld
Expenses incurred for advisory committee meeting	30,000
Expenses incurred for Advisory Committee meeting	11,000
Limited Partnerships \| Minimum
RELATED PARTY TRANSACTIONS
Percentage of ownership interest	40.00%
Limited Partnerships \| Maximum
RELATED PARTY TRANSACTIONS
Percentage of ownership interest	50.00%
General Partner or Management Company
RELATED PARTY TRANSACTIONS
Costs related to professional services	925,000	1,431,000	686,000
Repairs and maintenance	368,000
Administrative expense	350,000
Rental commission	56,000
Expenses for construction, architectural services and supervision of capital projects	151,000
Management Company
RELATED PARTY TRANSACTIONS
Reimbursement to related party for payroll transfers	3,230,000	2,926,000	2,606,000
Employer contributions in 401K plan	0	0	0
Number of accounting staff of related party providing bookkeeping and accounting functions	14
Fees for accounting and bookkeeping services	125,000	125,000	125,000
Number of employees having ownership interest in the investment properties	6
Hamilton Company
RELATED PARTY TRANSACTIONS
Management fee as percentage of gross receipts rental revenue	4.00%
Repairs and maintenance	80,000
Administrative expense	42,000
Rental commission	16,000
Expenses for construction, architectural services and supervision of capital projects	165,000
Amount paid to related party	955,000
Management fee	652,000
Dexter Park
RELATED PARTY TRANSACTIONS
Management fee as percentage of gross receipts rental revenue	2.00%
President of Management Company
RELATED PARTY TRANSACTIONS
Quarterly fee for asset management consulting services	18,750	18,750	18,750
Fee for asset management consulting services	75,000	75,000	75,000
Harold Brown \| Minimum
RELATED PARTY TRANSACTIONS
Percentage of ownership interest	43.20%
Harold Brown \| Maximum
RELATED PARTY TRANSACTIONS
Percentage of ownership interest	57.00%
HBC
RELATED PARTY TRANSACTIONS
Borrowings								7,168,000
Interest rate (as a percent)								6.00%
Term of mortgage loan								4 years
Notice period demanding early payment								6 months
Principal paydown of debt upon notice							2,500,000
Repayment of loan									918,600		2,500,000
Amount of principal payments				1,000,000	1,000,000	1,000,000				750,000
Outstanding amount of mortgage loan												1,668,600
Interest paid			$ 18,960