Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
OPERATING ACTIVITIES
Net income	$ 271	$ 147
Adjustments to reconcile net income to cash provided by operating activities:
Provision (benefit) for credit losses	464	(11)
Deferred tax (benefit) expense	(61)	9
Depreciation, amortization, and accretion, net	126	34
Stock based compensation expense	12	0
Realized gains on investment securities available for sale, net	0	(9)
Marketable equity securities gains, net	(3)	(16)
Net gain on sales of loans	(8)	(9)
Gain on sales of premises and equipment	(1)	0
Net gains on other real estate owned	(2)	(1)
Gain on acquisition	(431)	0
Gain on extinguishment of debt	(6)	0
Net change in assets held for sale	(183)	(15)
Net change in other assets	365	42
Net change in other liabilities	66	(38)
Other operating activities	(209)	(7)
Net cash provided by operating activities	400	126
CASH FLOWS FROM INVESTING ACTIVITIES
Net change in loans	(295)	(404)
Purchases of investment securities available for sale	(810)	(1,738)
Purchases of investment securities held to maturity	0	(207)
Proceeds from maturities of investment securities available for sale	330	1,079
Proceeds from maturities of investment securities held to maturity	283	206
Proceeds from sales of investment securities available for sale	0	352
Proceeds from sales of marketable equity securities	0	1
Net decrease (increase) in interest earning deposits at banks	2,705	(3,241)
Net change in securities purchased under resale agreements	0	0
Proceeds from sales of other real estate owned	11	10
Proceeds from sales of loans	260	0
Proceeds from sales of premises and equipment	19	1
Purchases of premises and equipment	(241)	(25)
Acquisition, net of cash acquired	134	0
Other investing activities	(14)	(24)
Net cash (used in) provided by investing activities	2,382	(3,990)
CASH FLOWS FROM FINANCING ACTIVITIES
Net change in time deposits	(833)	(159)
Net change in demand and other interest-bearing deposits	1,275	4,059
Net increase in short-term borrowings	27	39
Repayment of long-term borrowings	3,031	18
Proceeds from issuance of long-term borrowings	1	0
Cash dividends paid	(14)	(9)
Other financing activities	(22)	0
Net cash (used in) provided by financing activities	(2,597)	3,912
Change in cash and due from banks	185	48
Cash and due from banks at beginning of period	338	362
Cash and due from banks at end of period	523	410
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Interest	122	20
Income taxes	(1)	0
Significant non-cash investing and financing activities:
Transfers of loans to other real estate	1	2
Transfers of premises and equipment to other real estate	4	5
Dividends declared but not paid	1	5
Transfer of assets from held for investment to held for sale	22	44
Transfer of assets from held for sale to held for investment	1	0
Loans held for sale exchanged for investment securities	38	64
Commitments extended during the period on affordable housing investment credits	0	4
Common Stock | Issued for Acquisition
Issuance of stock	5,279	0
Common Stock | Issued for Stock Based Compensation
Issuance of stock	71	0
Preferred Stock | Issued for Acquisition
Issuance of stock	$ 541	$ 0