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Stock-Based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2021
Share-based Payment Arrangement [Abstract] |
Target grants performance share | Target grants of performance shares outstanding at December 31, 2021, were as follows:
Grant Date | Performance Period | Target Grant of Shares
February 2020 | 2020-2022 | 273,918 |
February 2021 | 2021-2023 | 281,129 |
Schedule of share-based payment award, performance shares, valuation assumptions | Assumptions used for grants applicable to the market condition for certain performance shares issued in 2021, 2020 and 2019 were:
|  | 2021 |  |  |  | 2020 |  |  |  | 2019 |
Weighted average grant-date fair value |  | $37.96 |  |  |  | $40.75 |  |  |  | $35.07 |
Blended volatility range |  | 35.37% - 46.35% |  |  | 15.30% - 15.97% |  |  | 19.50% - 19.69%
Risk-free interest rate range |  | .02% - .20% |  |  | 1.45% - 1.62% |  |  | 2.46% - 2.55%
Weighted average discounted dividends per share |  | $3.16 |  |  |  | $2.91 |  |  |  | $2.85 |
Summary of the status of the performance share awards | A summary of the status of the performance share awards for the year ended December 31, 2021, was as follows:
| Number of Shares | Weighted Average Grant-Date Fair Value
Nonvested at beginning of period | 613,174 |  | $ | 33.24 |
Granted | 284,104 |  | 32.66 |
Additional performance shares earned | 116,467 |  | 22.68 |
Less: |  |
Vested | 443,661 |  | 28.57 |
Forfeited | 15,037 |  | 35.49 |
Nonvested at end of period | 555,047 |  | $ | 34.40 |

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- Definition Tabular disclosure of share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5047-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the changes in outstanding nonvested performance-based units. + 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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