Loans and Related Allowance for Credit Losses, Commercial Loan Categories by Delinquency Status (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 945,906	$ 895,394	$ 862,827
Total nonaccrual loans	5,587	7,212
Total Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	549,970	513,120
Total nonaccrual loans	1,703	2,376
Total Commercial [Member] | Current-29 days past due and still accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	544,833	508,685
Total Commercial [Member] | 30-89 days past due and still accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	2,632	1,824
Total Commercial [Member] | 90 days or more past due and still accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	802	235
Commercial and industrial loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	379,694	350,436
Nonaccrual loans	742	980
Commercial and industrial loans [Member] | Current-29 days past due and still accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	376,262	348,033
Commercial and industrial loans [Member] | 30-89 days past due and still accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	1,991	1,217
Commercial and industrial loans [Member] | 90 days or more past due and still accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	699	206
Real estate mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	133,770	127,733
Nonaccrual loans	850	1,235
Real estate mortgage [Member] | Current-29 days past due and still accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	132,528	126,184
Real estate mortgage [Member] | 30-89 days past due and still accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	321	285
Real estate mortgage [Member] | 90 days or more past due and still accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	71	29
Real estate construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	21,889	20,092
Nonaccrual loans	3	13
Real estate construction [Member] | Current-29 days past due and still accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	21,697	19,900
Real estate construction [Member] | 30-89 days past due and still accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	157	179
Real estate construction [Member] | 90 days or more past due and still accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	32	0
Lease financing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Lease financing	14,617	14,859
Nonaccrual lease financing	108	148
Lease financing [Member] | Current-29 days past due and still accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Lease financing	14,346	14,568
Lease financing [Member] | 30-89 days past due and still accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Lease financing	163	143
Lease financing [Member] | 90 days or more past due and still accruing [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Lease financing	$ 0	$ 0