Loans and Leases - Schedule of Loans and Leases Delinquency Status (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	$ 65,524	$ 32,372	$ 33,181
Total Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	529	137
30-59 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	287	71
60-89 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	61	16
90 days or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	181	50
Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	64,995	32,235
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	50,101	22,586
Commercial | Total Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	365	57
Commercial | 30-59 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	210	33
Commercial | 60-89 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	44	5
Commercial | 90 days or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	111	19
Commercial | Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	49,736	22,529
Commercial | Commercial construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	2,633	1,238
Commercial | Commercial construction | Total Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	57	3
Commercial | Commercial construction | 30-59 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	55	1
Commercial | Commercial construction | 60-89 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	0	0
Commercial | Commercial construction | 90 days or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	2	2
Commercial | Commercial construction | Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	2,576	1,235
Commercial | Owner occupied commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	13,553	12,099
Commercial | Owner occupied commercial mortgage | Total Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	51	31
Commercial | Owner occupied commercial mortgage | 30-59 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	22	21
Commercial | Owner occupied commercial mortgage | 60-89 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	16	1
Commercial | Owner occupied commercial mortgage | 90 days or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	13	9
Commercial | Owner occupied commercial mortgage | Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	13,502	12,068
Commercial | Non-owner occupied commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	9,293	3,041
Commercial | Non-owner occupied commercial mortgage | Total Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	80	5
Commercial | Non-owner occupied commercial mortgage | 30-59 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	20	3
Commercial | Non-owner occupied commercial mortgage | 60-89 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	0	0
Commercial | Non-owner occupied commercial mortgage | 90 days or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	60	2
Commercial | Non-owner occupied commercial mortgage | Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	9,213	3,036
Commercial | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	22,402	5,937
Commercial | Commercial and industrial | Total Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	111	16
Commercial | Commercial and industrial | 30-59 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	73	8
Commercial | Commercial and industrial | 60-89 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	15	3
Commercial | Commercial and industrial | 90 days or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	23	5
Commercial | Commercial and industrial | Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	22,291	5,921
Commercial | Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	2,220	271
Commercial | Leases | Total Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	66	2
Commercial | Leases | 30-59 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	40	0
Commercial | Leases | 60-89 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	13	1
Commercial | Leases | 90 days or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	13	1
Commercial | Leases | Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	2,154	269
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	15,423	9,786
Consumer | Total Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	164	80
Consumer | 30-59 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	77	38
Consumer | 60-89 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	17	11
Consumer | 90 days or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	70	31
Consumer | Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	15,259	9,706
Consumer | Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	11,711	6,088
Consumer | Residential mortgage | Total Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	134	53
Consumer | Residential mortgage | 30-59 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	63	24
Consumer | Residential mortgage | 60-89 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	12	6
Consumer | Residential mortgage | 90 days or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	59	23
Consumer | Residential mortgage | Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	11,577	6,035
Consumer | Revolving mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	1,840	1,818
Consumer | Revolving mortgage | Total Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	17	14
Consumer | Revolving mortgage | 30-59 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	6	6
Consumer | Revolving mortgage | 60-89 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	2	2
Consumer | Revolving mortgage | 90 days or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	9	6
Consumer | Revolving mortgage | Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	1,823	1,804
Consumer | Consumer auto
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	1,320	1,332
Consumer | Consumer auto | Total Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	8	8
Consumer | Consumer auto | 30-59 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	6	6
Consumer | Consumer auto | 60-89 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	1	1
Consumer | Consumer auto | 90 days or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	1	1
Consumer | Consumer auto | Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	1,312	1,324
Consumer | Consumer other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	552	548
Consumer | Consumer other | Total Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	5	5
Consumer | Consumer other | 30-59 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	2	2
Consumer | Consumer other | 60-89 days past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	2	2
Consumer | Consumer other | 90 days or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	1	1
Consumer | Consumer other | Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	$ 547	$ 543