Acquisitions - Narrative (Details) - Eaton Vance - USD ($) shares in Millions, $ in Millions		1 Months Ended
Mar. 01, 2021	Mar. 31, 2021
Business Acquisition [Line Items]
Voting interests acquired (as a percent)	100.00%
Consideration transferred in business acquisition	$ 8,700
Cash consideration transferred	3,400
Net revenues of acquiree since acquisition date		$ 174
Net income of acquiree since acquisition date		$ 31
Common Stock, $0.01 par value
Business Acquisition [Line Items]
Fair value of shares transferred in acquisition	$ 5,300
Stock issued in acquisition (shares)	69

Number of shares of equity interests issued or issuable to acquire entity.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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