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Consolidated Statements of Equity (Parenthetical) - shares | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Balance (in units/ shares) | 110,241,868 | 101,292,299 | 98,498,651 | 94,531,512
Conversion of common units to common shares (in shares/units) | 1,904,615 | 339,513 | 87,000 |
Exercise of share options (in units/shares) |  | 5,000 |  |
Restricted common units/shares net of redemptions | 146,290 | 179,180 | 158,912 |
Forward Equity Sale Agreement [Member] |  |  |  |
Shares issued to the public (in units/shares) | 5,907,000 | 1,678,913 |  |
Common Stock Issued to Public Under At-the-Market Program [Member] |  |  |  |
Shares issued to the public (in units/shares) | 991,664 | 591,042 | 3,721,227 |

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