Shareholders' Equity - Summary of Amount of Common Stock Repurchased by the Firm (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Equity [Abstract]
Common share repurchases (in shares)	3.0	2.5	5.9	14.1
Average cost per share (in dollars per share)	$ 332.32	$ 395.28	$ 337.32	$ 333.61
Total cost of common share repurchases	$ 1,000	$ 1,000	$ 2,000	$ 4,700

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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