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Stockholders' Equity / Partners' Capital Narrative (Details) $ / shares in Units, $ in Millions |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
May 22, 2020 USD ($) yr | Dec. 31, 2020 $ / shares shares | Dec. 31, 2019 $ / shares shares | Mar. 27, 2018 $ / shares | Jun. 02, 2017 USD ($)
Class of Stock [Line Items] |  |  |  |  |
Common Stock, Shares, Outstanding |  | 155,718,825 | 154,790,298 |  |
General Partners' Capital Account, Units Outstanding (in units) |  | 1,730,921 |  |  |
Limited Partners' Capital Account, Units Outstanding (in units) |  | 153,987,904 |  |  |
Options exercised |  | 43,792 | 145,088 |  |
Shares of Common Stock issued in connection with redemption of an equal number of OP Units (in shares) |  | 856,811 | 144,481 |  |
ATM Program [Member] |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
At The Market Stock Offering Program Aggregate Value Of Common Stock | $ | $ 600.0 |  |  |  | $ 600.0
At Market Stock Offering Program Maximum Length Of Sale (in years) | yr | 3 |  |  |  |
Series B Cumulative Redeemable Preferred Stock / Unit [Member] |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
Series B, Shares Outstanding (in shares) |  | 80,000 | 80,000 |  |
Series B, Dividend Rate, Percentage |  | 5.25% | 5.25% |  |
Series B, Liquidation Preference Per Share (dollars per share) | $ / shares |  | $ 2,500.00 | $ 2,500 | $ 2,500.00 |
Depositary shares of Series B Cumulative Redeemable Preferred [Member] |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
Series B, Shares Outstanding (in shares) |  | 8,000,000 | 8,000,000 |  |
Series B, Liquidation Preference Per Share (dollars per share) | $ / shares |  | $ 25.00 |  | $ 25.00 |

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