Accounting Policies - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Variable Interest Entity [Line Items]
Assets of managed investment entities	$ 4,332		$ 4,332		$ 4,484
Liabilities of managed investment entities	4,168		4,168		4,307
Operating lease liability	$ 235		$ 235		$ 198
Operating lease liability, current, Statement of Financial Position	Other Liabilities		Other Liabilities		Other Liabilities
Operating lease right-of-use asset	$ 214		$ 214		$ 176
Operating lease, right-of-use asset, Statement of Financial Position	Other Assets		Other Assets		Other Assets
Weighted average common shares adjustment related to stock-based compensation (shares)	0	100,000	100,000	100,000
Anti-dilutive potential common shares related to stock-based compensation plans (shares)	0		0	0
Maturities of short term investments			3 months
New collateralized loan obligation, temporary warehousing entities
Variable Interest Entity [Line Items]
Assets of managed investment entities	$ 35		$ 35
Liabilities of managed investment entities	$ 25		$ 25