Revenue from Contract with Customer (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 180	$ 171	$ 358	$ 340
Revenue from other sources (non-financial services revenue)	195	165	377	332
Total Fee income and Other revenue	375	336	735	672
Accounts Receivable, after Allowance for Credit Loss	109		109		$ 96
Retirement
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	166	153	331	304
DistributionFeesMember \| Retirement
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 14	$ 18	$ 27	$ 36

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.

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+ Details

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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