Derivatives - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Derivative [Line Items]
Shareholders’ equity	$ 291,646	$ 291,646	$ 273,197	$ 270,066	$ 272,924
Net income (loss) in AOCI expected to be reclassified, after tax		(3,400)
Net income (loss) in AOCI expected to be reclassified		$ (4,600)
Open cash flow hedge, forecasted transactions hedging period (in years)		10 years
Terminated cash flow hedges, period forecasted transaction recognized in interest income (in years)		5 years
Bank of America, N.A.
Derivative [Line Items]
Collateral not yet posted	1,100	$ 1,100
Credit derivatives
Derivative [Line Items]
Cash and securities held as collateral	104,100	104,100	101,300
Cash and securities collateral posted	93,400	93,400	81,200
Collateral not yet posted	2,500	2,500
Foreign Mortgage-backed Securities and Foreign Securities
Derivative [Line Items]
Transfer of mortgage-backed securities to third-party trust	4,100	4,100	4,800
Gross cash proceeds from transfer of securities	4,200	4,200	4,900
Fair value of derecognized assets	4,100	4,100	4,700
Derivatives
Derivative [Line Items]
Shareholders’ equity	(8,016)	(8,016)	(11,935)	(1,880)	$ 426
Pretax income (loss) in accumulated OCI	(10,700)	(10,700)
Pretax losses reclassified from accumulated OCI		3,159	303	(221)
Derivatives | Market making and similar activities
Derivative [Line Items]
Pretax losses reclassified from accumulated OCI	$ 2,000	$ 2,031	$ 0	$ 0