Fair Value - Changes in FV under the FV Option (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value gains (losses)	$ 404	$ 529	$ 608	$ 1,009
Loans
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value gains (losses)	(49)	(187)	22	(378)
Long-term debt:
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value gains (losses)	$ 219	$ 558	$ (50)	$ 1,600