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Interest on trustee fees.

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Maximum ownership percentage of outstanding common shares to exempt common share ownership limit.

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Maximum ownership percentage of outstanding preferred shares to exempt equity ownership limit.

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Payments for property management fees.

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Percentage of cash bonus.

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Preferred share ownership limit.

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Related party transaction agreement date.

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Carrying value as of the balance sheet date of obligations incurred and payable for incentive compensation awarded to employees and directors or earned by them based on the terms of one or more relevant arrangements.

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The aggregate amount of expenditures for salaries, wages, profit sharing and incentive compensation, and other employee benefits, including equity-based compensation, and pension and other postretirement benefit expense.

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Expenditures for salaries of officers. Does not include allocated share-based compensation, pension and post-retirement benefit expense or other labor-related non-salary expense. For commercial and industrial companies, excludes any direct and overhead labor that is included in cost of goods sold.

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Payments of cash to employees, including wages and salaries, during the current period.

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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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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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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Percentage of vesting of share-based compensation awards.

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Fees charged annually for the professional services of a trustee, usually quoted as a percentage of the funds being managed. The fee for appointing an offshore Trustee is included in the trust price.

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Related Party Transactions - Additional Information (Detail) - USD ($) $ in Thousands					1 Months Ended	3 Months Ended		12 Months Ended
	Apr. 06, 2018	Mar. 30, 2018	Dec. 23, 2016	Dec. 20, 2016	Jan. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Related Party Transaction [Line Items]
Reimbursed for general and administrative expense paid on IRT						$ 2,925	$ 3,487
Ballard Spahr LLP
Related Party Transaction [Line Items]
Trustee fee paid						$ 32
LFFP
Related Party Transaction [Line Items]
Maximum common shares ownership percentage that would exempt common share ownership limit		8.30%
LFFP \| Subsequent Event
Related Party Transaction [Line Items]
Maximum preferred shares ownership percentage that would exempt equity ownership limit	9.80%
Frischer Cooperation Agreement \| Subsequent Event
Related Party Transaction [Line Items]
Related party transaction agreement date	Apr. 06, 2018
Highland Capital Management, L. P.
Related Party Transaction [Line Items]
Related party transaction agreement date						May 26, 2017
IRT
Related Party Transaction [Line Items]
Reimbursed for general and administrative services						$ 387
Reimbursed for general and administrative expense paid on IRT						155
Payments for property management fees						137
Earned and paid on consulting agreement						94
IRT \| Chief Executive Officer
Related Party Transaction [Line Items]
Compensation received				$ 375
Number of shares awarded, share			150,000
Cash payments					$ 500
IRT \| Chief Executive Officer \| Six Month Anniversary
Related Party Transaction [Line Items]
Vesting percentage			50.00%
IRT \| Chief Executive Officer \| One Year Anniversary
Related Party Transaction [Line Items]
Vesting percentage			50.00%
IRT \| James J. Sebra's
Related Party Transaction [Line Items]
Percentage of cash bonus								25.00%
Bonus						110
Maximum \| Ballard Spahr LLP
Related Party Transaction [Line Items]
Interest on trustee fee						$ 1
Maximum \| LFFP
Related Party Transaction [Line Items]
Common Share Ownership Limit		12.50%
Maximum \| LFFP \| Subsequent Event
Related Party Transaction [Line Items]
Preferred Share Ownership Limit	15.00%