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Stock-Based Compensation Plans - Additional Information (Detail) $ / shares in Units, $ in Millions | 8 Months Ended |  |  |  |
--- | --- | --- | --- | --- | ---
May 09, 2021 USD ($) shares | Dec. 11, 2020 closingSharePricePerOpeningSharePrice shares | Dec. 01, 2020 $ / shares | Nov. 30, 2020 $ / shares | Aug. 30, 2020 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares | 4,373,000 |  |  |  | 5,174,000
MandatoryProportionalAdjustmentedtoRestrictedStockUnits | (94,000) |  |  |  |
Share Price | $ / shares |  |  | $ 384.50 | $ 391.77 |
Additional number of shares authorized |  | 222,000 |  |  |
SpecialCashDividendSharesAdjustmentRatio | closingSharePricePerOpeningSharePrice |  | 1.019 |  |  |
2019 Incentive Plan [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Additional number of shares authorized | 17,500,000 |  |  |  |
Restricted Stock Units (RSUs) |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Additional number of shares authorized | 10,000,000 |  |  |  |
Number of shares available to be granted | 11,981,000 |  |  |  |
Time-based RSUs awards outstanding | 4,242,000 |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares | 29,000 |  |  |  |
Unrecognized compensation cost | $ | $ 852 |  |  |  |
Weighted-average recognition period | 1 year 8 months 12 days |  |  |  |
Performance Shares [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Outstanding performance-based RSUs awards granted, subject to achievement of performance targets | 102,000 |  |  |  |
Maximum [Member] | 2019 Incentive Plan [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Number of shares available to be granted | 27,800,000 |  |  |  |
Maximum [Member] | Restricted Stock Units (RSUs) |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Number of shares available to be granted | 15,885,000 |  |  |  |

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