Non-U.S. Activities - Narrative (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)
Segment Reporting Information [Line Items]
Total assets	$ 371,070		$ 371,070		$ 353,240
Non-U.S.
Segment Reporting Information [Line Items]
Service fees, percent		0.47	0.48	0.47
Management fees, percent	0.25	0.24	0.25	0.25
Total assets	$ 94,350	$ 95,260	$ 94,350	$ 95,260

Amount of asset recognized for present right to economic benefit.

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+ Details