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Share Incentive and Other Compensation - Additional Information (Details) - USD ($) |  | 12 Months Ended
--- | --- | ---
Mar. 23, 2020 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Unit based compensation |  | $ 10,912,000 | $ 10,957,000 | $ 12,948,000 |
Trustee fees |  | 1,400,000 | 1,400,000 |  |
Total unrecognized compensation cost related to nonvested awards |  | $ 15,100,000 |  |  |
Weighted-average period over which cost is expected to be recognized |  | 1 year 6 months |  |  |
Performance Period Ending December 31, 2021 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Award vesting percentage |  | 33.30% |  |  |
Award vesting period |  | 3 years |  |  |
LTIP Units |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Total fair value of shares that vested |  | $ 7,600,000 | 8,500,000 |  |
LTIP Units | Trustee |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Shares issued during period, share-based compensation, net of forfeitures |  | 42,680 |  |  |
Shares granted to trustees for trustee fees vesting on one year anniversary of grant date |  | 17,492 |  |  |
LTIP Units | Performance Period Ending December 31, 2021 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Award vesting percentage |  | 66.70% |  |  |
Award vesting period |  | 3 years |  |  |
LTIP Units | Tranche One | Trustee |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Shares issued during period, share-based compensation, net of forfeitures |  | 25,188 |  |  |
Restricted shares |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Total fair value of shares that vested |  | $ 500,000 | $ 600,000 |  |
Restricted shares | Trustee |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Shares issued during period, share-based compensation, net of forfeitures |  | 53,058 |  |  |
Shares granted to trustees for trustee fees vesting on one year anniversary of grant date |  | 19,474 |  |  |
Restricted shares | Tranche One | Trustee |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Shares issued during period, share-based compensation, net of forfeitures |  | 33,584 |  |  |
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 |  | $ 10,400,000 |  |  |
Weighted average grant date fair value, grants (in dollars per share) |  | $ 18.86 | $ 32.50 |  |
LTIP Units and Restricted Stock | Trustee |  |  |  |  |
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% |  |  |
LTIP Units and Restricted Stock | General and Administrative Expense |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Unit based compensation |  | $ 8,400,000 | $ 8,800,000 | 8,400,000 |
LTIP Units and Restricted Stock | Performance Period Ending December 31, 2021 |  |  |  |  |
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 and Restricted Stock | Minimum | 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% |  |  |
LTIP Units and Restricted Stock | Minimum | 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% |  |  |
LTIP Units and Restricted Stock | Maximum | 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% |  |  |
LTIP Units and Restricted Stock | Maximum | 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% |  |  |
Employee Benefit Plans |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Compensation expense |  | $ 300,000 | $ 300,000 | 300,000 |
2020 Plan |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Increase in number of shares authorized | 2,650,000 |  |  |  |
Number of shares authorized |  | 2,738,013 |  |  |
Share Incentive Plan | LTIP Units |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Shares issued during period, share-based compensation, net of forfeitures |  | 396,149 |  |  |
Share Incentive Plan | Restricted shares |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Shares issued during period, share-based compensation, net of forfeitures |  | 13,766 |  |  |
Performance Shares 2019 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Performance period |  | 3 years | 3 years |  |
Volatility rate |  | 21.00% | 19.60% |  |
Risk-free interest rates |  | 1.40% | 2.50% |  |
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] |  |  |  |  |
Percentage of promote awarded as share based compensation award |  | 25.00% |  |  |
Compensation expense |  | $ 0 | $ 0 | 0 |
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% |  |  |
Awards in connection with fund to have intrinsic value |  | $ 0 |  |  |
Compensation expense |  | $ 0 | 0 | 0 |
Long Term Investment Alignment Program | Fund V |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Percentage of promote awarded as share based compensation award |  | 4.20% |  |  |
Awards in connection with fund to have intrinsic value |  | $ 0 |  |  |
Compensation expense |  | $ 0 | $ 0 | $ 0 |

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