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Related Party Transactions (Details) $ in Thousands |  | 12 Months Ended |
--- | --- | --- | ---
Sep. 03, 2019 shares | Dec. 31, 2020 USD ($) Vehicles shares | Dec. 31, 2019 USD ($) Vehicles shares | Dec. 31, 2018 USD ($) | May 21, 2019 shares
Related Party Transaction [Line Items] |  |  |  |  |
Number Of Non Employee Directors Electing To Receive Deferred Stock Units | Vehicles |  | 7 |  |  |
Separate Unrestricted Cash For Deferred Compensation Plan. |  | $ 39,500 | $ 36,700 |  |
Liability for directors |  | $ 336,264 | $ 377,553 |  |
Common stock, shares issued | shares |  | 155,797,725 | 154,869,198 |  |
OP Units for redemption (in shares) | shares | 4,917 |  |  |  |
Deferred stock units outstanding | Vehicles |  | 72,966 | 60,676 |  |
Director Cessation Member [Member] |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Common stock, shares issued | shares |  |  |  |  | 17,949
Director |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Separate Unrestricted Cash For Deferred Compensation Plan. |  | $ 800 | $ 700 |  |
Liability for directors |  | 800 | 700 |  |
Immediate Family Member of Management or Principal Owner |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Related Party Transaction, Expenses from Transactions with Related Party |  | 914 | 21 | $ 921 |
Real Estate Brokerage Firm |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |
Related Party Transaction, Expenses from Transactions with Related Party |  | $ 3,400 | $ 2,600 |  |

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