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Stock-Based Compensation (Tables) | 6 Months Ended
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Jun. 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 |  |  | 369,975 |  |  |  |  | 449,054 |
Forfeited |  |  | (81,046 | ) |  |  |  | (127,603 | )
Shares delivered |  |  | (136,182 | ) |  |  |  | (163,078 | )
Balance at June 30, |  |  | 1,049,210 |  |  |  |  | 915,159 |
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:
|  | June 30 |
In thousands |  | 2020 |  |  |  | 2019 |
Three months ended |  | $ | 1,292 |  |  |  | $ | 1,161 |
Six months ended |  |  | 2,377 |  |  |  |  | 1,595 |
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 |  |  | (104,801 | ) |  |  |  | 21.57 |  |  |  | (446,435 | ) |  |  | 21.06 |
Outstanding at June 30, |  |  | 1,128,686 |  |  |  | $ | 20.28 |  |  |  | 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:
|  | June 30 |
In thousands |  | 2020 |  |  |  | 2019 |
Three months ended |  | $ | — |  |  |  | $ | — |
Six months ended |  |  | — |  |  |  |  | 43 |

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