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Shareholders’ Equity (Tables) | 9 Months Ended
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Sep. 30, 2020
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 nine months ended September 30, 2020 and 2019.
| Preferred stock |  | Common stock
Common and Preferred Stock Activity (in shares): | Series A Convertible |  | Treasury |  | Outstanding
Beginning balance as of December 31, 2019 | 67,323 |  |  | 7,186,521 |  |  | 89,185,661 |
Conversion of convertible preferred stock | (1,284) |  |  | — |  |  | 128,389 |
Issuance for share-based compensation plans | — |  |  | — |  |  | 170,784 |
Ending balance as of September 30, 2020 | 66,039 |  |  | 7,186,521 |  |  | 89,484,834 |
Beginning balance as of December 31, 2018 | 71,967 |  |  | 7,186,521 |  |  | 88,103,440 |
Conversion of convertible preferred stock | (3,392) |  |  | — |  |  | 339,166 |
Issuance for share-based compensation plans | — |  |  | — |  |  | 451,161 |
Ending balance as of September 30, 2019 | 68,575 |  |  | 7,186,521 |  |  | 88,893,767 |

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