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Consolidated Statements of Equity (Parenthetical) - shares | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Shares outstanding (in units/ shares) | 112,181,759 | 112,068,705 | 110,241,868 | 101,292,299
Conversion of common units to common shares (in shares/units) | 14,009 | 105,039 | 1,904,615 |
Common shares issued during the period (in units/shares) |  | 1,000 |  |
Share-based compensation issuance, net of redemptions (in shares/units) | 99,045 | 106,711 | 146,290 |
Forward Equity Sale Agreement |  |  |  |
Common shares issued during the period (in units/shares) |  | 1,614,087 | 5,907,000 |
Common Stock At-the-Market Program |  |  |  |
Common shares issued during the period (in units/shares) |  |  | 991,664 |

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