Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Per share weighted average intrinsic value of equity-based compensation awards granted. Excludes stock and unit options.

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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 maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Exchange Ratio

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Percentage of Target Value to be Paid Out

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Unrecognized compensation cost related to long term incentive plan units.

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Equity Incentive Plan - Additional Information (Details)								1 Months Ended	3 Months Ended		12 Months Ended
	Mar. 01, 2019 $ / shares shares	Jan. 31, 2019 shares	Mar. 01, 2018 shares	Mar. 01, 2017 shares	Jan. 28, 2016 shares	Jun. 01, 2015 shares	May 17, 2013 shares	Jan. 31, 2018 shares	Mar. 31, 2019 USD ($) shares	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($) shares
Independent Trustees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common share issued as compensation for services performed (in shares)		27,870						21,670
Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)							3,000,000
Vesting period for share awards under equity							3 years
Common shares available for issuance (in shares)									1,372,659
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs \| $									$ 100,000		$ 100,000
Weighted-average period for recognition of unrecognized compensation costs									2 years 3 months 18 days
Compensation expense, recognized \| $									$ 15,700	$ 100,000
Number of shares, Granted (in shares)									0		5,000
Long Term Incentive Plan Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average period for recognition of unrecognized compensation costs									2 years 2 months 12 days
Compensation expense, recognized \| $									$ 900,000	$ 700,000
Exchange ratio									1
Number of shares, Granted (in shares)									221,853		244,917
Total unrecognized compensation cost related to LTIP Units \| $									$ 8,200,000		$ 7,800,000
Long Term Incentive Plan Units \| Awarded June 1, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, Granted (in shares)						183,300
Long Term Incentive Plan Units, Time-Based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, Granted (in shares)	88,746		97,968	89,574	72,966
Long Term Incentive Plan Units, Time-Based \| Awarded March 1, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, Granted (in shares)	88,746
Long Term Incentive Plan Units, Performance-Based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, Granted (in shares)	133,107		146,949	134,348	39,285
Long Term Incentive Plan Units, Performance-Based \| Awarded March 1, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, Granted (in shares)	133,107
Grants in period, intrinsic value, amount per share (in dollars per share) \| $ / shares	$ 18.91
Long Term Incentive Plan Units, Performance-Based \| Awarded March 1, 2019 \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of units paid out	50.00%
Long Term Incentive Plan Units, Performance-Based \| Awarded March 1, 2019 \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of units paid out	150.00%