Basis of Presentation - Out of Period Correction (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Correction Related to Defined Benefit Plans [Member]
Out-of-period correction
Out-of-period correction	$ 29
Correction Related to Performance Fees [Member]
Out-of-period correction
Out-of-period correction		$ 19

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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