Long Term Incentive and Share Based Compensation Expense

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- Definition

Maximum Percentage of Promote To Be Awarded as Share Based Compensation Awards. Promote is defined as the amount above a certain performance measurement threshold.

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Percentage of Promote Awarded as Share Based Compensation Award

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- Definition

Share-based Compensation, Granted, for Service, Vesting on One Year Anniversary of Grant Date

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No definition available.

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- Definition

Share-based Compensation, Granted, for Service, Vesting Rate Beginning on the First Anniversary of Grant Date

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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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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

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.

+ References

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- Definition

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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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

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.

+ References

No definition available.

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- Definition

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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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

Value, after forfeitures, of stock or other type of equity granted of any equity-based compensation plan other than an employee stock ownership plan (ESOP).

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- Definition

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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- Definition

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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Share Incentive and Other Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense			$ 0.2	$ 0.2
Trustee fees			0.6	0.6
Total unrecognized compensation cost related to nonvested awards	$ 19.6		$ 19.6
Weighted-average period over which cost is expected to be recognized			1 year 9 months
LTIP Units and Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total value of restricted shares and LTIP units as of the grant date			$ 10.6
Unit based compensation			$ 4.3		$ 8.4
Weighted average grant date fair value, grants (in dollars per share)			$ 26.88		$ 31.69
LTIP Units and Restricted Stock \| Performance Period Ending December 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			3 years
LTIP Units and Restricted Stock \| Performance Fails To Achieve, Earned Performance-Based Shares Vest At End Of Performance Period
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			60.00%
LTIP Units and Restricted Stock \| Performance Fails To Achieve
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			40.00%
Award vesting period			2 years
LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			33.30%
Award vesting period			3 years
Total fair value of shares that vested			$ 9.1		$ 7.3
LTIP Units \| Performance Period Ending December 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			66.70%
Award vesting period			3 years
Restricted shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of shares that vested			$ 0.8		$ 0.7
Trustee \| LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures			17,427
Trustee \| LTIP Units \| Tranche 1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures			8,478
Trustee \| Restricted shares \| Tranche 1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures			11,869
General and Administrative Expense \| LTIP Units and Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unit based compensation	$ 2.1	$ 2.5	$ 4.3	4.5
Trustee \| LTIP Units and Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period			3 years
Annual vesting rate of shares granted to trustees that begin vesting on the second anniversary of grant date			33.00%
Trustee \| LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted to trustees for trustee fees vesting on one year anniversary of grant date	8,949		8,949
Trustee \| Restricted shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures			17,050
Shares granted to trustees for trustee fees vesting on one year anniversary of grant date	5,181		5,181
Second Amended 2016 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	1,185,947		1,185,947
Second Amended 2016 Plan \| LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures			381,821
Second Amended 2016 Plan \| Restricted shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued during period, share-based compensation, net of forfeitures			5,768
Long Term Investment Alignment Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Max percentage of future fund III promote that may be awarded to senior executives						25.00%
Long Term Investment Alignment Program \| Fund III
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense			$ 0.0	$ 0.4
Percentage of promote awarded as share based compensation award						25.00%
Long Term Investment Alignment Program \| Fund IV
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of promote awarded as share based compensation award						22.80%
Minimum \| LTIP Units and Restricted Stock \| TSR percentile falls between the 25th percentile and the 50th percentile
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			50.00%
Minimum \| LTIP Units and Restricted Stock \| TSR percentile falls between the 50th percentile and 75th percentile
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			100.00%
Maximum \| LTIP Units and Restricted Stock \| TSR percentile falls between the 25th percentile and the 50th percentile
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			100.00%
Maximum \| LTIP Units and Restricted Stock \| TSR percentile falls between the 50th percentile and 75th percentile
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			200.00%