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Stock-Based Compensation (Tables) | 9 Months Ended
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Sep. 30, 2020
Restricted Stock Units (RSU) and Performance Share Awards (PSAs) [Member] |
Summary of Share Based Compensation Activity | The following table summarizes RSU and PSA activity during periods indicated:
Units |  | 2020 |  |  |  | 2019 |
Balance at January 1, |  |  | 896,463 |  |  |  |  | 756,786 |
Granted |  |  | 386,995 |  |  |  |  | 484,108 |
Forfeited |  |  | (87,523 | ) |  |  |  | (158,767 | )
Shares delivered |  |  | (136,182 | ) |  |  |  | (163,078 | )
Balance at September 30, |  |  | 1,059,753 |  |  |  |  | 919,049 |
Compensation Expense for Stock Option Activity Included in Continuing Operations | The following table sets forth aggregate RSU and PSA compensation expense included in continuing operations for the periods indicated:
|  | September 30 |
In thousands |  | 2020 |  |  |  | 2019 |
Three months ended |  | $ | 1,617 |  |  |  | $ | 1,048 |
Nine months ended |  |  | 3,994 |  |  |  |  | 2,643 |
Stock Only Stock Appreciation Rights (SOSARs) [Member] |
Summary of Share Based Compensation Activity | The following table sets forth information related to outstanding SOSARS:
|  | 2020 |  |  | 2019 |
SOSARS |  | Shares |  |  |  | Wtd Avg Exercise Price |  |  | Shares |  |  | Wtd Avg Exercise Price |
Outstanding at January 1, |  |  | 1,291,947 |  |  |  | $ | 20.05 |  |  |  | 2,334,742 |  |  | $ | 18.08 |
Granted |  |  | — |  |  |  |  | — |  |  |  | — |  |  |  | — |
Exercised |  |  | (58,460 | ) |  |  |  | 12.85 |  |  |  | (441,920 | ) |  |  | 14.31 |
Canceled / forfeited |  |  | (151,074 | ) |  |  |  | 20.25 |  |  |  | (446,435 | ) |  |  | 21.06 |
Outstanding at September 30, |  |  | 1,082,413 |  |  |  | $ | 20.40 |  |  |  | 1,446,387 |  |  | $ | 19.31 |
Compensation Expense for Stock Option Activity Included in Continuing Operations | The following table sets forth SOSAR compensation expense included in continuing operations for the periods indicated:
|  | September 30 |
In thousands |  | 2020 |  |  |  | 2019 |
Three months ended |  | $ | — |  |  |  | $ | — |
Nine months ended |  |  | — |  |  |  |  | 40 |

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