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Share-based Compensation - Additional Information (Details) |  |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Aug. 31, 2018 | Aug. 31, 2017 | Aug. 31, 2014 shares | Dec. 31, 2019 USD ($) unit / shares fungible_unit shares | Dec. 31, 2018 USD ($) shares | Dec. 31, 2017 USD ($) shares | Dec. 31, 2016 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Capitalized to assets associated with compensation expense related to our long-term compensation plans, restricted stock and stock options |  |  |  | $ 2,100,000 | $ 6,300,000 | $ 7,200,000 |
Stock options, stock appreciation rights and other awards |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Expected life of option (in years) |  |  |  | 5 years |  |  |
All other awards |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Fungible units per share (in fungible units per share) | unit / shares |  |  |  | 1.0 |  |  |
Expected life of option (in years) |  |  |  | 10 years |  |  |
Stock options |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Expected life of option (in years) |  |  |  | 0 days | 3 years 6 months | 4 years 4 months 24 days |
Period of commencement of option vesting, from date of grant (in years) |  |  |  | 1 year |  |  |
Remaining weighted average contractual life of the options outstanding (in years) |  |  |  | 2 years 8 months 12 days |  |  |
Remaining weighted average contractual life of the options exercisable (in years) |  |  |  | 2 years 8 months 12 days |  |  |
Total unrecognized compensation cost related to unvested stock awards |  |  |  | $ 100,000 |  |  |
Weighted average period for recognition of compensation cost related to unvested stock awards (in years) |  |  |  | 2 months 12 days |  |  |
Weighted average fair value of options granted during the period |  |  |  | $ 0 | $ 84,068 | $ 3,816,652 |
Stock options | Minimum |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Award expiration period (in years) |  |  |  | 5 years |  |  |
Options vesting period (in years) |  |  |  | 1 year |  |  |
Stock options | Maximum |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Award expiration period (in years) |  |  |  | 10 years |  |  |
Options vesting period (in years) |  |  |  | 5 years |  |  |
Restricted Stock Awards |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Annual award vesting rate, low end of range (as a percent) |  |  |  | 15.00% |  |  |
Annual award vesting rate, high end of range (as a percent) |  |  |  | 35.00% |  |  |
Class O LTIP Units |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Preferred unit distributions as a percentage of common unit distributions |  |  |  | 10.00% |  |  |
Restricted Stock Awards |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Compensation expense |  |  |  | $ 12,892,249 | 12,757,704 | 9,809,749 |
Total unrecognized compensation cost related to unvested stock awards |  |  |  | $ 20,800,000 |  |  |
Weighted average period for recognition of compensation cost related to unvested stock awards (in years) |  |  |  | 2 years |  |  |
Fair value of restricted stock vested during the period |  |  |  | $ 12,100,000 | 9,800,000 | 9,400,000 |
Weighted average fair value of options granted during the period |  |  |  | $ 11,131,181 | $ 13,440,503 | $ 9,905,986 |
Awards granted (in shares) | shares |  |  |  | 126,350 | 162,900 | 96,185 |
Awards outstanding (in shares) | shares |  |  |  | 3,566,466 | 3,452,016 | 3,298,216 | 3,202,031
LTIP units |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Weighted average period for recognition of compensation cost related to unvested stock awards (in years) |  |  |  | 2 years 3 months 18 days |  |  |
Weighted average fair value of options granted during the period |  |  |  | $ 58,300,000 | $ 22,000,000.0 |  |
Performance Shares |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Total unrecognized compensation cost related to unvested stock awards |  |  |  | 31,200,000 |  |  |
Share-based Payment Arrangement, Noncash Expense |  |  |  | $ 22,200,000 | 24,400,000 | $ 26,100,000 |
Employee Stock |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Number of shares available for issuance (shares) | shares |  |  |  | 500,000 |  |  |
Shares of common stock available for issuance (shares) |  |  |  | 85.00% |  |  |
Duration of each offering period starting the first day of each calendar quarter (in months) |  |  |  | 3 months |  |  |
Shares of common stock issued (shares) | shares |  |  |  | 131,440 |  |  |
Fourth Amended and Restated 2003 Stock Option and Incentive Plan |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Maximum fungible units that may be granted (in shares) | fungible_unit |  |  |  | 27,030,000 |  |  |
Fungible units per share (in fungible units per share) | unit / shares |  |  |  | 3.74 |  |  |
Shares that may be issued if equal to fungible units (shares) (less than) | shares |  |  |  | 27,030,000 |  |  |
Fungible units | fungible_unit |  |  |  | 4,100,000 |  |  |
Stock options, stock appreciation rights and other awards |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Fungible units per share (in fungible units per share) | unit / shares |  |  |  | 0.73 |  |  |
Third Amendment and Restated 2005 Stock Option and Incentive Plan | Stock options |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Compensation expense |  |  |  | $ 2,500,000 | $ 5,400,000 | 7,800,000 |
2014 Outperformance Plan |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Compensation expense |  |  |  | 0 |  | $ 13,600,000 |
Capitalized to assets associated with compensation expense related to our long-term compensation plans, restricted stock and stock options |  |  |  | 27,900,000 |  |  |
Maximum award to be earned, if performance reaches maximum threshold, first performance period |  |  | 0.333 |  |  |  |
Maximum award to be earned, if performance reaches maximum threshold, first performance period |  |  | 0.667 |  |  |  |
Award period (in years) |  |  | 3 years |  |  |  |
Awards granted (in shares) | shares |  |  | 610,000 |  |  |  |
2014 Outperformance Plan | Vesting on August 31, 2017 |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Percentage of units vested |  | 50.00% |  |  |  |  |
2014 Outperformance Plan | Vesting on August 31, 2018 |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Percentage of units vested | 50.00% |  |  |  |  |  |
Deferred Stock Compensation Plan for Directors |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Compensation expense |  |  |  | $ 2,400,000 |  |  |
Maximum percentage of the annual retainer fee, chairman fees and meeting fees that may be deferred by non-employee directors (percent) |  |  |  | 100.00% |  |  |
Awards granted (in shares) | shares |  |  |  | 18,669 |  |  |
Shares issued (in shares) | shares |  |  |  | 9,949 |  |  |
Awards outstanding (in shares) | shares |  |  |  | 128,946 |  |  |

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- Definition Purchase price of common stock expressed as a percentage of its fair value. + References No definition available. + Details
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