Fair Value of Financial Instruments - Investments Held at Net Asset Value (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Fair value disclosure
Gain (loss) on investments	$ (23)	$ 2	$ (3)	$ (59)
Net Asset Value | Fair Value
Fair value disclosure
Investment in limited partnership	$ 7		$ 7		$ 10