CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Millions		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019
OPERATING ACTIVITIES
Net income		$ 601	$ 1,341
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for credit losses		1,492	283
Net change in loans held for sale		(655)	(697)
Depreciation, amortization and accretion		413	432
Amortization of intangibles		6	8
Deferred income taxes		(251)	(41)
Share-based compensation		34	44
Net gain on sales of:
Debt securities		(4)	(21)
Premises and equipment		0	(6)
Increase in other assets		(2,960)	(506)
Increase in other liabilities		569	133
Net cash (used in) provided by operating activities		(755)	970
Investment securities:
Purchases of debt securities available for sale		(5,547)	(4,633)
Proceeds from maturities and paydowns of debt securities available for sale		4,583	2,728
Proceeds from sales of debt securities available for sale		48	1,495
Proceeds from maturities and paydowns of debt securities held to maturity		629	280
Net decrease in equity securities, at fair value		0	136
Net decrease in equity securities, at cost		202	100
Net increase in interest-bearing deposits in banks		(31)	(10)
Acquisitions, net of cash acquired		(3)	(129)
Net increase in loans and leases		(5,303)	(1,534)
Capital expenditures, net		1	(47)
Other		(78)	(172)
Net cash used in investing activities		(5,499)	(1,786)
FINANCING ACTIVITIES
Net increase in deposits		17,608	5,139
Net decrease in short-term borrowed funds		(43)	(244)
Proceeds from issuance of long-term borrowed funds		8,323	7,300
Repayments of long-term borrowed funds		(13,258)	(10,556)
Treasury stock purchased		(270)	(820)
Net proceeds from issuance of preferred stock		395	293
Dividends declared and paid to common stockholders		(504)	(459)
Dividends declared and paid to preferred stockholders		(73)	(48)
Premium paid to exchange subordinated debt		(80)	0
Payments of employee tax withholding for share-based compensation		(14)	(21)
Net cash provided by financing activities		12,084	584
(Decrease) increase in cash and cash equivalents	[1]	5,830	(232)
Cash and cash equivalents at beginning of period	[1]	3,386	4,074
Cash and cash equivalents at end of period	[1]	$ 9,216	$ 3,842

[1] Cash and cash equivalents includes cash and due from banks and interest-bearing cash and due from banks as reflected on the Consolidated Balance Sheets.