Fair Value - Changes in FV under the FV Option (Details) - 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 [Line Items]
Fair value gains (losses)	$ 529	$ (446)	$ 1,009	$ 338
Loans
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value gains (losses)	(187)	(5)	(378)	20
Long-term debt
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value gains (losses)	$ 558	$ (89)	$ 1,600	$ 284