Income Taxes - Schedule of Income Taxes Expenses Benefit Reconciliation (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income taxes at statutory federal income tax rate	$ 760	$ 548	$ 516
Increase (decrease) in taxes:
Tax-exempt income	(51)	(37)	(21)
State and local income taxes, net of federal income tax effect	161	110	101
Qualified affordable housing project tax benefits, net	(26)	(22)	(15)
Other	34	21	15
Income taxes	$ 878	$ 620	$ 596