Shareholders' Equity - Summary of Amount of Common Stock Repurchased by the Firm (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions |
12 Months Ended | ||
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Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Equity [Abstract] | |||
| Common share repurchases | 8.2 | 25.8 | 13.9 |
| Average cost per share | $ 236.35 | $ 206.56 | $ 236.22 |
| Total cost of common share repurchases | $ 1,928 | $ 5,335 | $ 3,294 |
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- References No definition available.
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- Definition Total cost of shares repurchased divided by the total number of shares repurchased. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of shares that have been repurchased during the period and are being held in treasury. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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