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Share-Based Compensation Plans (Tables) | 12 Months Ended
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Dec. 31, 2020
Share-based Payment Arrangement [Abstract] |
Share-based Compensation Expense Recognized in Continuing Operations | The following table summarizes share-based compensation expense recognized in the Consolidated Statements of Income in Compensation and benefits (in millions):
Years ended December 31 | 2020 |  | 2019 |  | 2018
Restricted share units (“RSUs”) | $ | 186 |  |  | $ | 198 |  |  | $ | 186 |
Performance share awards (“PSAs”) | 116 |  |  | 110 |  |  | 143 |
Employee share purchase plans | 10 |  |  | 9 |  |  | 9 |
Total share-based compensation expense | 312 |  |  | 317 |  |  | 338 |
Tax benefit | 61 |  |  | 66 |  |  | 74 |
Share-based compensation expense, net of tax | $ | 251 |  |  | $ | 251 |  |  | $ | 264 |
Restricted Share Unit Activity | The following table summarizes the status of the Company’s RSUs (shares in thousands, except fair value):
| 2020 |  | 2019 |  | 2018
Years ended December 31 | Shares |  | Fair Value at Date of Grant (1) |  | Shares |  | Fair Value at Date of Grant (1) |  | Shares |  | Fair Value at Date of Grant (1)
Non-vested at beginning of year | 3,634 |  |  | $ | 143 |  |  | 4,208 |  |  | $ | 120 |  |  | 4,849 |  |  | $ | 104 |
Granted | 1,329 |  |  | $ | 185 |  |  | 1,306 |  |  | $ | 175 |  |  | 1,500 |  |  | $ | 141 |
Vested | (1,426) |  |  | $ | 133 |  |  | (1,661) |  |  | $ | 113 |  |  | (1,943) |  |  | $ | 97 |
Forfeited | (228) |  |  | $ | 157 |  |  | (219) |  |  | $ | 131 |  |  | (198) |  |  | $ | 114 |
Non-vested at end of year | 3,309 |  |  | $ | 163 |  |  | 3,634 |  |  | $ | 143 |  |  | 4,208 |  |  | $ | 120 |
(1)Represents per share weighted average fair value of award at date of grant.
Schedule of Performance-based Plans Information | The following table summarizes the Company’s target PSAs granted and shares that would be issued at current performance levels for PSAs granted during the years ended December 31, 2020, 2019, and 2018, respectively (shares in thousands and dollars in millions, except fair value):
| 2020 |  | 2019 |  | 2018
Target PSAs granted during period | 500 |  |  | 467 |  |  | 564 |
Weighted average fair value per share at date of grant | $ | 161 |  |  | $ | 165 |  |  | $ | 134 |
Number of shares that would be issued based on current performance levels | 495 |  |  | 784 |  |  | 830 |
Unamortized expense, based on current performance levels | $ | 58 |  |  | $ | 41 |  |  | $ | — |

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- Definition Tabular disclosure of cost recognized for award under share-based payment arrangement by plan. Includes, but is not limited to, related tax benefit. + 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 (h)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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