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Shareholders’ Equity (Tables) | 3 Months Ended
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Mar. 31, 2021
Stockholders' Equity Note [Abstract] |
Common and preferred stock activity | The Common and Preferred Stock table below contains additional information about preferred stock conversions during the three months ended March 31, 2021 and 2020.
| Preferred stock |  | Common stock
Common and Preferred Stock Activity (in shares): | Series A Convertible |  | Treasury |  | Outstanding
Beginning balance as of December 31, 2020 | 63,589 |  |  | 7,186,521 |  |  | 90,055,797 |
Conversion of convertible preferred stock | (137) |  |  | — |  |  | 13,697 |
Issuance for share-based compensation plans | — |  |  | — |  |  | 18,220 |
Ending balance as of March 31, 2021 | 63,452 |  |  | 7,186,521 |  |  | 90,087,714 |
Beginning balance as of December 31, 2019 | 67,323 |  |  | 7,186,521 |  |  | 89,185,661 |
Conversion of convertible preferred stock | (1,182) |  |  | — |  |  | 118,146 |
Issuance for share-based compensation plans | — |  |  | — |  |  | 157,158 |
Ending balance as of March 31, 2020 | 66,141 |  |  | 7,186,521 |  |  | 89,460,965 |

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