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Share Based Compensation, Annual Retainer Payable, Cash Percentage

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Share Based Compensation, Annual Retainer Payable, Restricted Stock Units Percentage

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Share-Based Compensation Arrangement By Share-Based Payment Award, Absolute Shareholder Return, Percent

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Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Shares Authorized, Value

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Share-Based Compensation Arrangement By Share-Based Payment Award, Relative Shareholder Return Excess, Rate

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Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Market Capitalization Maximum

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Share-based Compensation Arrangement by Share-based Payment Award, Percent of Distributions

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Share-based Compensation Arrangement by Share-based Payment Award, Requisite Performance Period

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- Definition

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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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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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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- Definition

Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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Amount of cash outflow in the form of ordinary dividends provided by the non-wholly owned subsidiary to noncontrolling interests.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, 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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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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Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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Number of share instruments newly issued under a share-based compensation plan.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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Percentage of vesting of share-based compensation awards.

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- Definition

Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

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Share-Based Compensation - Narrative (Details) - USD ($)				3 Months Ended		9 Months Ended		12 Months Ended
	Jul. 19, 2018	Jun. 02, 2018	Jun. 02, 2015	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Distributions to non-controlling interest holders						$ 448,000
Distributions paid						$ 448,000	$ 574,000
Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued in lieu of cash (shares)						0	0
Restricted Share Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual retainer payable, cash				50.00%		50.00%
Annual retainer payable, restricted stock units				50.00%		50.00%
Restricted Share Plan \| Independent Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual retainer payable				$ 100,000		$ 100,000
Restricted Share Plan \| Non-Executive Chair
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual retainer payable				105,000		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		30,000
2015 OPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during the period (shares)			3,013,933.0666666667
Compensation (income) expense				$ 1,900,000	$ (1,000,000)	$ (800,000)	$ (3,200,000)
Requisite service period						2 years 9 months 35 days
Award value, percent of market capitalization			5.00%
Distribution percent entitled to by LTIP holders				10.00%		10.00%
2015 OPP \| Target
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted share vesting period			3 years
Award performance period			3 years
2015 OPP \| Below Threshold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted share vesting period			1 year
2015 OPP \| Threshold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted share vesting period			2 years
2018 Multi Year Outperformance Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum award value	$ 50,000,000
Share price (usd per share)	$ 19.57
2018 Multi Year Outperformance Plan \| Target
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Absolute TSR	30.00%
Relative TSR excess	0
2018 Multi Year Outperformance Plan \| Below Threshold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Absolute TSR	24.00%
Relative TSR excess	(0.06)
2018 Multi Year Outperformance Plan \| Threshold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Absolute TSR	24.00%
Relative TSR excess	(0.06)
2018 Multi Year Outperformance Plan \| Minimum \| Tier One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Absolute TSR	24.00%
Relative TSR excess	(0.06)
2018 Multi Year Outperformance Plan \| Minimum \| Tier Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Absolute TSR	36.00%
Relative TSR excess	0.00
2018 Multi Year Outperformance Plan \| Maximum \| Tier One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Absolute TSR	30.00%
Relative TSR excess	0.00
2018 Multi Year Outperformance Plan \| Maximum \| Tier Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Absolute TSR	30.00%
Relative TSR excess	0.06
Stock Options \| Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (shares)				500,000.0		500,000.0
Shares issued during the period (shares)						0		0
Restricted Stock Units (RSUs) \| Restricted Share Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted share vesting period						3 years
Percentage of maximum Common Stock available for issuance						10.00%
Restricted Stock \| Restricted Share Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation (income) expense				$ 100,000	$ 100,000	$ 400,000	500,000
Restricted Stock \| Restricted Share Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense				800,000		$ 800,000
Weighted average period of recognition						2 years
LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Distributions paid				200,000		$ 400,000	$ 500,000
LTIP Units \| Target
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percent						33.33%
LTIP Units \| Below Threshold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percent						33.33%
LTIP Units \| Threshold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percent						33.33%
LTIP Units \| Advisor
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Distributions to non-controlling interest holders				$ 100,000
LTIP Units \| 2018 Multi Year Outperformance Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during the period (shares)		2,554,930
LTIP Units \| 2018 Multi Year Outperformance Plan \| Advisor
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during the period (shares)	2,554,930