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Share-Based Payments (Tables) | 9 Months Ended
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Sep. 30, 2021
Stock Awards |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Schedule of Share-based Compensation Arrangements by Share-based Payment Award | The following is a summary of stock award activity for the nine months ended September 30, 2021:
| Shares |  | Weighted Average Grant-Date Fair Value
Nonvested, January 1, 2021 | 128,664 |  |  | $ | 44.30 |
Granted | 57,650 |  |  | 43.10 |
Vested | (47,646) |  |  | 42.98 |
Forfeited | (2,075) |  |  | 40.95 |
Nonvested, September 30, 2021 | 136,593 |  |  | $ | 44.30 |
Stock Performance Awards |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Schedule of Share-based Compensation Arrangements by Share-based Payment Award | The following is a summary of stock performance award activity for the nine months ended September 30, 2021 (share amounts reflect awards at target):
| Shares |  | Weighted Average Grant-Date Fair Value
Nonvested, January 1, 2021 | 164,600 |  |  | $ | 42.32 |
Granted | 79,000 |  |  | 38.34 |
Vested | (54,000) |  |  | 35.73 |
Forfeited | — |  |  | — |
Nonvested, September 30, 2021 | 189,600 |  |  | $ | 42.54 |
Schedule of Weighted-Average Assumptions | The grant date fair value of stock performance awards granted during the nine months ended September 30, 2021 and 2020 was determined using a Monte Carlo fair value simulation model incorporating the following assumptions:
| 2021 |  | 2020
Risk-free interest rate | 0.18 | % |  | 1.42 | %
Expected term (in years) | 3.00 |  | 3.00
Expected volatility | 32.00 | % |  | 19.00 | %
Dividend yield | 3.60 | % |  | 2.80 | %

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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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