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Share-Based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2020
Share-based Payment Arrangement, Noncash Expense [Abstract] |
Performance Award Details | The following table presents details of the performance awards described above.
Award Year | Service Conditions Lapse date | Performance Period | Award Conditions |  | Shares outstanding at 12/31/2020 (shares) | Grant Date Fair Value (in millions)
2020 | 02/28/23 | 01/01/2020- 12/31/2022 | Non-GAAP Financial Measure |  | 392,619 |  | $ | 11.7 |
Operational Measures |  | 90,604 |  | $ | 2.6 |
2019 | 02/28/22 | 01/01/2019- 12/31/2021 | Non-GAAP Financial Measure |  | 384,680 |  | $ | 11.7 |
Operational Measures |  | 88,769 |  | $ | 2.5 |
2018 | 02/26/21 | 01/01/2018- 12/31/2020 | Non-GAAP Financial Measure |  | 347,479 |  | $ | 9.2 |
Operational Measures(1) |  | 80,185 |  | $ | 2.4 |
(1) Grant date fair value amount represents the service inception date fair value of these awards as they are not yet granted.
Restricted Stock Units (RSUs) |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Schedule Of Transactions Of Share Based Compensation Other Than Stock Options |
(shares) | Restricted Stock Units |  | Weighted Average Award Date Fair Value Per Unit ($)
Non-vested at December 31, 2019 | 302,606 |  |  | 23.49 |
Granted | 235,100 |  |  | 25.77 |
Forfeited | (38,220) |  |  | 24.18 |
Vested | (21,259) |  |  | 24.68 |
Non-vested at December 31, 2020 | 478,227 |  |  | 24.51 |
Performance Shares |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Schedule Of Transactions Of Share Based Compensation Other Than Stock Options |
(shares) | Performance Awards |  | Weighted Average Grant Date Fair Value Per Unit ($)(1)
Non-vested at December 31, 2019 | 1,503,251 |  |  | 22.74 |
Granted | 528,729 |  |  | 27.01 |
Forfeited | (118,716) |  |  | 25.63 |
Vested | (528,928) |  |  | 28.30 |
Non-vested at December 31, 2020 | 1,384,336 |  |  | 25.09 |

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- Definition Tabular disclosure of activity for outstanding award under share-based payment arrangement excluding share and unit options and nonvested award. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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