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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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Share-Based Compensation - Narrative (Details)						3 Months Ended		6 Months Ended		12 Months Ended
Share-Based Compensation - Narrative (Details)	Feb. 28, 2017	Feb. 25, 2016 company	Jun. 02, 2015 USD ($) shares	Apr. 08, 2015	Apr. 07, 2015 shares	Jun. 30, 2017 USD ($) shares	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) shares	Jun. 30, 2016 USD ($) shares	Dec. 31, 2016 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Distributions paid related to LTIP Units								$ 415,000	$ 1,344,000
OP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reverse stock split conversion ratio	0.3333
OPP (LTIP Units)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reverse stock split conversion ratio	0.3333
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reverse stock split conversion ratio	0.3333
Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued in lieu of cash (shares) \| shares								0	0
Restricted Share Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual retainer payable, cash (percent)			50.00%
Annual retainer payable, restricted stock units (percent)			50.00%
Restricted Share Plan \| Independent Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual retainer payable			$ 100,000
Restricted Share Plan \| Non-Executive Chair
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual retainer payable			105,000
Restricted Share Plan \| Directors, Servicing on Committees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual retainer payable			$ 30,000
OPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during the period (shares) \| shares			3,013,933
Restricted share vesting period								30 days
Compensation (income) expense						$ (2,200,000)	$ (18,000)	$ (2,600,000)	$ 900,000
Award value, percent of market capitalization (percent)			5.00%
Requisite service period			5 years					5 years
Distribution percent entitled to by LTIP holders						10.00%		10.00%
Distributions paid related to LTIP Units						$ 200,000		$ 300,000
Number of companies (company) \| company		2
OPP \| Period Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted share vesting period			3 years
Percentage of units vested			33.33333%
OPP \| Period One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted share vesting period			1 year
Percentage of units vested			33.33333%
OPP \| Period Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted share vesting period			2 years
Percentage of units vested			33.33333%
Stock Options \| Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (shares) \| shares						500,000.0		500,000.0
Shares issued during the period (shares) \| shares								0		0
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (shares) \| shares								0
Restricted Stock \| Restricted Share Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted automatically upon election to board of directors (shares) \| shares					1,000
Restricted share vesting period				5 years	5 years
Periodic vesting percentage					20.00%
Compensation (income) expense							$ 100,000		$ 200,000
Restricted Stock \| Restricted Share Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation costs not yet recognized						$ 900,000		$ 900,000
Weighted average period of recognition								2 years 7 months 30 days
Compensation (income) expense						$ 100,000		$ 400,000
Restricted Stock Units (RSUs) \| Restricted Share Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted share vesting period			3 years