Investments - Investment Segment (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Schedule of Investments
Securities sold, not yet purchased, at fair value	$ 748		$ 1,382
Investment Segment
Schedule of Investments
Securities sold, not yet purchased, at fair value	748		1,382
Portion of unrealized gains and (losses) that relates to equity and debt securities still held	65	$ 223
Investment Segment \| Equity securities
Schedule of Investments
Equity securities	1,530		2,146
Investment Segment \| Communications
Schedule of Investments
Equity securities	165		371
Investment Segment \| Consumer, cyclical
Schedule of Investments
Equity securities	169		180
Investment Segment \| Energy
Schedule of Investments
Equity securities	81		71
Securities sold, not yet purchased, at fair value	361		798
Investment Segment \| Utilities
Schedule of Investments
Equity securities	158		622
Securities sold, not yet purchased, at fair value	305		525
Investment Segment \| Healthcare
Schedule of Investments
Equity securities	56		99
Investment Segment \| Financial [Member]
Schedule of Investments
Equity securities	24
Investment Segment \| Materials
Schedule of Investments
Equity securities	310		288
Investment Segment \| Industrial
Schedule of Investments
Equity securities	567		515
Securities sold, not yet purchased, at fair value	$ 82		$ 59