Description of loan amendment terms.

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Mortgage prepayment penalty.

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The project fee that may be charged for real estate project.

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Replenish account balance.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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

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No definition available.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount of assets pledged to secure a debt instrument.

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

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

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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.

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No definition available.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Face (par) amount of the original debt instrument that was repurchased.

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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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No definition available.

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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 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.

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Amount of the fees associated with providing collateral for the credit facility.

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No definition available.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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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.

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The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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No definition available.

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- Definition

Amount of operating lease expense. Excludes sublease income.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Amount of cash inflow (outflow) from long-term debt wholly or partially secured by collateral. Excludes tax exempt secured debt.

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Amount of a short-term obligation that has been excluded from current liabilities in the balance sheet because of a refinancing of the obligation.

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Carrying amount as of the balance sheet date of improvements having a life longer than one year that were made for the benefit of one or more tenants.

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Mortgage financings (Details) - USD ($)			1 Months Ended			3 Months Ended	6 Months Ended		12 Months Ended
Mortgage financings (Details) - USD ($)	Feb. 07, 2018	Dec. 07, 2017	Feb. 28, 2018	Apr. 28, 2017	Nov. 23, 2016	Apr. 30, 2018	Apr. 30, 2018	Apr. 30, 2017	Oct. 31, 2017	Oct. 30, 2013	Mar. 01, 2018	Jan. 08, 2018	Sep. 29, 2016	Jun. 30, 2016	Apr. 22, 2016	Feb. 01, 2010
Debt Instrument [Line Items]
Total loan carrying amount						$ 352,623,000	$ 352,623,000		$ 323,435,000
Proceeds from credit line								$ 3,000,000
Grande Rotunda LLC [Member]
Debt Instrument [Line Items]
Fee amount			$ 900,000			45,000	1,400,000			$ 500,000
Station Place on Monmouth, LLC [Member]
Debt Instrument [Line Items]
Percentage of acquisition		100.00%
People's United Bank [Member]
Debt Instrument [Line Items]
Loan amount						20,100,000	20,100,000						$ 25,800,000
Total loan carrying amount															$ 2,320,000
Grande Rotunda LLC Construction Loan [Member]
Debt Instrument [Line Items]
Loan amount						$ 121,900,000	$ 121,900,000
Fixed interest rate						3.00%	3.00%
Maturity date of loan							Mar. 05, 2020
Rotunda [Member]
Debt Instrument [Line Items]
Loan amount						$ 118,500,000	$ 118,500,000
Fixed interest rate						4.73%	4.73%
Provident Bank [Member]
Debt Instrument [Line Items]
Loan amount		$ 12,350,000				$ 16,200,000	$ 16,200,000
Fixed interest rate		4.35%
Basis points, interest rate		1.80%				2.75%	1.25%
Debt Instrument, Collateral Amount									3,100,000
Maturity date of loan		Dec. 15, 2027					Dec. 15, 2024
Tanant improvements									3,000,000
Line of credit, current borrowing capacity						$ 12,800,000	$ 12,800,000
Line of credit			$ 3,100,000
Line of credit, maximum borrowing capacity						$ 13,000,000	$ 13,000,000
Line of credit, renewal									$ 100,000
Patchogue NY [Member] \| Mortgages [Member]
Debt Instrument [Line Items]
Fixed rate mortgage loans												$ 29,100,000
Fixed interest rate						5.38%	5.38%
Debt Instrument, Collateral Amount											$ 5,200,000
Patchogue NY [Member] \| Mortgages [Member] \| Pierre Towers, LLC [Member]
Debt Instrument [Line Items]
Loan amount						$ 48,000,000	$ 48,000,000
Fixed interest rate						3.88%	3.88%
Total loan carrying amount						$ 960,000	$ 960,000
Term of the loan							10 years
Net proceeds from refinancing of debt							$ 17,200,000
Mortgage prepayment penalty							1,200,000
Baltimore, MD [Member] \| Notes Payable, Other Payables [Member]
Debt Instrument [Line Items]
Loan amount																$ 22,500,000
Debt Instrument, Collateral Amount																$ 19,500,000
Total loan carrying amount					$ 2,100,000
Baltimore, MD [Member] \| Notes Payable, Other Payables [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Total loan carrying amount						116,100,000	116,100,000
Baltimore, MD [Member] \| Notes Payable, Other Payables [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Total loan carrying amount						$ 120,000,000	$ 120,000,000
Baltimore, MD [Member] \| People's United Bank [Member]
Debt Instrument [Line Items]
Basis points, interest rate						2.25%
Term of the loan						4 years
Description of loan amendment terms					On November 23, 2016, the following terms and conditions of this loan were modified: (i) the total amount that could have been drawn on this loan was decreased from $120 million to $116.1 million, allowing for an additional draw of $2.1 million over the then existing balance of approximately $114 million to be used for retail tenant improvements and leasing commissions; (ii) leasing benchmarks were no longer required to be met including the waiver of the leasing benchmarks FREIT was not in compliance with as of June 30, 2016; (iii) Grande Rotunda, LLC provided an interest reserve to Wells Fargo Bank in the amount of $2 million for the purpose of funding interest payments, and was obliged to replenish the account balance to $1 million if it should fall below $500,000; (iv) the maturity date of the loan was changed from December 31, 2017 to October 31, 2017 with no option to extend; and (v) the interest rate on the amount outstanding on the loan was increased by 25 basis points to 250 basis points over the monthly LIBOR.
Grande Rotunda LLC [Member] \| Mortgages [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Replenish account balance														$ 500,000
Grande Rotunda LLC [Member] \| Mortgages [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Replenish account balance														$ 1,000,000
Wells Fargo Bank [Member]
Debt Instrument [Line Items]
Fixed interest rate	3.00%
Total loan carrying amount	$ 115,300,000
Tanant improvements	118,500,000
Leasing costs	$ 3,380,000
Wells Fargo Bank [Member] \| Manufacturer's and Traders Trust Company [Member]
Debt Instrument [Line Items]
Loan amount				$ 23,500,000
S And A Commercial Associates Limited Partnership [Member] \| Mortgages [Member]
Debt Instrument [Line Items]
Membership interest percentage						65.00%	65.00%
Repurchase amount of acquisition loan						$ 11,200,000	$ 11,200,000
WestFREIT Corp [Member]
Debt Instrument [Line Items]
Refinanced loan amount				$ 22,000,000
Basis points, interest rate				2.75%
Maturity date of loan				Apr. 28, 2019
Description of loan amendment terms				This refinancing resulted in: (i) a reduction in the annual interest rate from a fixed rate of 5.55% to a variable rate
Net proceeds from refinancing of debt				$ 1,100,000