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Share-Based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2020
Share-based Payment Arrangement [Abstract] |
Valuation assumptions |
| Year Ended December 31,
| 2020 |  | 2019 |  | 2018
Dividend yield | — | % |  | — | % |  | — | %
Expected volatility | 16.6 % |  | 18.1 | % |  | 21.3 | %
Risk free interest rate | 1.2 % |  | 2.5 | % |  | 2.8 | %
Expected option life | 6.0 years |  | 6.0 years |  | 6.0 years
Option activity | A summary of stock option and SAR activity under the Company’s Long Term Incentive and Share Award Plans during 2020 is presented below:
| Year Ended December 31, 2020
| Number of Options / SARs |  | Weighted Average Exercise Price |  | Weighted Average Contractual Term |  | Aggregate Intrinsic Value
Outstanding, beginning of year | 18,853,018 |  |  | $ | 20.94 |  |  |  |  |
Granted | 1,121,833 |  |  | $ | 42.34 |  |  |  |  |
Exercised | (1,981,216) |  |  | $ | 10.92 |  |  |  |  |
Forfeited or expired | (154,302) |  |  | $ | 30.13 |  |  |  |  |
Outstanding, end of year | 17,839,333 |  |  | $ | 23.32 |  |  | 4.74 |  | $ | 234,659 |
Exercisable, end of year | 15,132,810 |  |  | $ | 21.30 |  |  | 4.10 |  | $ | 223,908 |
Weighted average grant date fair value |
| Year Ended December 31,
| 2020 |  | 2019 |  | 2018
Weighted average grant date fair value | $ | 8.14 |  |  | $ | 7.90 |  |  | $ | 7.50 |
Aggregate intrinsic value of Options/SARs exercised | $ | 59,723 |  |  | $ | 51,350 |  |  | $ | 43,468 |
Unvested restricted share and unit activity | A summary of restricted share and restricted unit activity under the Company’s Long Term Incentive and Share Award Plans for 2020 is presented below:
| Restricted Common Shares |  | Restricted Unit Awards
Unvested Shares: |  |  |
Unvested balance, beginning of year | 1,045,921 |  |  | 1,563,012 |
Granted | 1,328,033 |  |  | 207,297 |
Vested | (697,090) |  |  | (620,905) |
Forfeited | (41,019) |  |  | (27,685) |
Unvested balance, end of year | 1,635,845 |  |  | 1,121,719 |
Weighted Average Grant Date Fair Value: |  |  |
Unvested balance, beginning of year | $ | 31.02 |  |  | $ | 30.07 |
Granted | $ | 37.58 |  |  | $ | 37.32 |
Vested | $ | 30.86 |  |  | $ | 29.99 |
Forfeited | $ | 33.91 |  |  | $ | 30.76 |
Unvested balance, end of year | $ | 36.34 |  |  | $ | 31.43 |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Performance shares and units, valuation assumptions |
| Year Ended December 31,
| 2020 |  | 2019 |  | 2018
Expected volatility | 18.1 % |  | 17.1 % |  | 16.2 %
Risk free interest rate | 1.1 % |  | 2.5 % |  | 2.6 %
Unvested performance share and unit activity |
| Performance Shares |  | Performance Units
Unvested Shares: |  |  |
Unvested balance, beginning of year | 1,400,914 |  |  | 23,767 |
Granted | 548,906 |  |  | 8,298 |
Vested | — |  |  | — |
Forfeited | (98,438) |  |  | — |
Unvested balance, end of year | 1,851,382 |  |  | 32,065 |
Weighted Average Grant Date Fair Value: |  |  |
Unvested balance, beginning of year | $ | 30.29 |  |  | $ | 29.75 |
Granted | $ | 44.17 |  |  | $ | 44.17 |
Vested | $ | — |  |  | $ | — |
Forfeited | $ | 30.01 |  |  | $ | — |
Unvested balance, end of year | $ | 34.42 |  |  | $ | 33.48 |
Share based compensation expense | The following tables present pre-tax and after-tax share-based compensation expense recognized as well as the unrecognized compensation cost associated with unvested awards and the weighted average period over which it is expected to be recognized.
| Year Ended December 31,
| 2020 |  | 2019 |  | 2018
Pre-Tax |  |  |  |  |
Stock options and SARs | $ | 11,744 |  |  | $ | 12,866 |  |  | $ | 16,272 |
Restricted share and unit awards | 41,284 |  |  | 38,988 |  |  | 34,025 |
Performance awards | 14,729 |  |  | 8,949 |  |  | 4,414 |
ESPP | 2,135 |  |  | 3,045 |  |  | 1,224 |
Total | $ | 69,892 |  |  | $ | 63,848 |  |  | $ | 55,935 |
After-Tax |  |  |  |  |
Stock options and SARs | $ | 10,388 |  |  | $ | 11,450 |  |  | $ | 14,894 |
Restricted share and unit awards | 34,599 |  |  | 32,999 |  |  | 29,044 |
Performance awards | 13,380 |  |  | 8,295 |  |  | 4,127 |
ESPP | 1,978 |  |  | 2,758 |  |  | 1,114 |
Total | $ | 60,345 |  |  | $ | 55,502 |  |  | $ | 49,179 |
Unrecognized compensation cost |
| December 31, 2020
| Stock Options and SARs |  | Restricted Common Shares and Units |  | Performance Common Shares and Units
Unrecognized compensation cost related to unvested awards | $ | 9,333 |  |  | $ | 52,726 |  |  | $ | 9,450 |
Weighted average recognition period (years) | 1.02 |  | 1.48 |  | 0.66
Restricted Common Shares And Restricted Units |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Weighted average grant date fair value of restricted stock | The following table presents the weighted average grant date fair value of restricted shares and restricted unit awards granted and the aggregate fair value of restricted shares and unit awards vesting in each year.
| Year Ended December 31,
| 2020 |  | 2019 |  | 2018
Restricted shares and restricted unit awards granted | 1,535,330 |  |  | 1,195,741 |  |  | 1,563,287 |
Weighted average grant date fair value | $ | 37.55 |  |  | $ | 32.89 |  |  | $ | 26.86 |
Aggregate fair value of vested restricted share and unit awards | $ | 39,703 |  |  | $ | 46,262 |  |  | $ | 39,898 |
Performance Common Shares and Units |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Weighted average grant date fair value of restricted stock | The following table presents the weighted average grant date fair values of performance awards granted.
| Year Ended December 31,
| 2020 |  | 2019 |  | 2018
Performance awards | 557,204 |  |  | 696,360 |  |  | 743,513 |
Weighted average grant date fair value | $ | 44.17 |  |  | $ | 36.05 |  |  | $ | 24.77 |

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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of share based awards other than stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References No definition available. + Details
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- Definition Tabular disclosure for stock option plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value. + 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 (d) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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