Fair Value Measurements - Gains or losses recorded related to fair value option (Details) - Fair Value Option - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Fair Value, Option, Quantitative Disclosures
Fair value option gain (loss)	$ (274)	$ 486	$ 26	$ 875
Other bond securities
Fair Value, Option, Quantitative Disclosures
Fair value option gain (loss)	(175)	96	(376)	(3)
Alternative investments
Fair Value, Option, Quantitative Disclosures
Fair value option gain (loss)	(167)	428	231	845
Long-term debt
Fair Value, Option, Quantitative Disclosures
Fair value option gain (loss)	$ 68	$ (38)	$ 171	$ 33