Fair Value - Schedule of Gain (Losses) Recorded for Financial Instruments Elected the Fair Value Option (Details) - Retirement Services - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	$ (983)	$ 1,164
Trading securities
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	(252)	75
Mortgage loans
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	(751)	1,041
Investment funds
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	(10)	41
Future policy benefits
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	24	(5)
Other
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	$ 6	$ 12

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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