Variable Interest Entities - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Variable Interest Entity [Line Items]
Other comprehensive income (loss), net of tax	$ (475)	$ 2,598
Other investments	5,256		$ 5,015
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Other comprehensive income (loss), net of tax	0	$ 0
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Other investments	$ 4,500		$ 4,200