Parent Company Financial Statements - Condensed Statements of Income - Parent Company Only (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income
Dividends from consolidated nonbank subsidiaries	$ 0	$ 3,000,000,000
Securities losses, net	(82,000,000)	(7,000,000)	$ 62,000,000
Total interest income	6,587,000,000	5,211,000,000	5,572,000,000
Expenses
Interest	978,000,000	441,000,000	790,000,000
Other	295,000,000	294,000,000	306,000,000
Applicable income tax expense	647,000,000	747,000,000	370,000,000
Net Income	2,446,000,000	2,770,000,000	1,427,000,000
Other Comprehensive Income	(6,317,000,000)	(1,394,000,000)	1,409,000,000
Parent Company
Income
Dividends from consolidated nonbank subsidiaries	165,000,000	3,040,000,000	1,285,000,000
Securities losses, net	(9,000,000)	1,000,000	1,000,000
Interest	11,000,000	11,000,000	17,000,000
Total interest income	167,000,000	3,052,000,000	1,303,000,000
Expenses
Interest	311,000,000	250,000,000	266,000,000
Other	19,000,000	30,000,000	26,000,000
Total expenses	330,000,000	280,000,000	292,000,000
(Loss) Income Before Income Taxes and Equity in Undistributed Earnings of Subsidiaries	(163,000,000)	2,772,000,000	1,011,000,000
Applicable income tax expense	(76,000,000)	(62,000,000)	(65,000,000)
(Loss) Income Before Equity in Undistributed Earnings of Subsidiaries	(87,000,000)	2,834,000,000	1,076,000,000
Equity in undistributed earnings	2,533,000,000	(64,000,000)	351,000,000
Net Income	2,446,000,000	2,770,000,000	1,427,000,000
Other Comprehensive Income	0	0	0
Comprehensive Income Attributable to Bancorp	2,446,000,000	2,770,000,000	1,427,000,000
Dividends from Bancorp's banking subsidiary to the Bancorp's non-bank subsidiary	$ 0	$ 3,000,000,000	$ 1,300,000,000