Consolidated Statements Of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Statement of Cash Flows [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 633	$ 658
Provision for Loan, Lease, and Other Losses	35	46
Depreciation, Depletion and Amortization, Nonproduction	143	141
Share-based Payment Arrangement, Noncash Expense	23	22
Deferred Income Tax Expense (Benefit)	(2)	(4)
Increase (Decrease) in Debt Securities, Trading, and Equity Securities, FV-NI	174	28
Increase (Decrease) in Loans Held-for-sale	77	32
Increase (Decrease) in Operating Liabilities	(66)	105
Increase (Decrease) in Other Operating Assets	146	(27)
Other Noncash Income (Expense)	23	18
Net cash provided by (used in) operating activities	346	825
Payments for (Proceeds from) Short-term Investments	(426)	(146)
Proceeds from Maturities, Prepayments and Calls of Held-to-maturity Securities	311	284
Payments to Acquire Held-to-maturity Securities	195	265
Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-sale	2,222	2,396
Payments to Acquire Available-for-sale Securities	1,271	2,260
Payments for (Proceeds from) Other Loans and Leases	2,085	981
Net change in other noninterest-bearing investments	83	29
Payments to Acquire Property, Plant, and Equipment	94	90
Payments for (Proceeds from) Other Investing Activities	0	(2)
Net Cash Provided by (Used in) Investing Activities, Total	(603)	(739)
Increase (Decrease) in Deposits	2,039	1,169
Proceeds from (Repayments of) Short-term Debt	(1,074)	804
Repayments of debt over 90 days and up to one year	0	2,000
Proceeds from (Repayments of) Debt	497	497
Proceeds from Issuance of Common Stock	8	19
Payments for Repurchase of Common Stock	826	434
Payments of Dividends	196	172
Proceeds from (Payments for) Other Financing Activities	(9)	0
Net Cash Provided by (Used in) Financing Activities, Total	439	(117)
Net increase (decrease) in cash and due from banks	182	(31)
Cash and Due from Banks	796	517
Interest Paid, Including Capitalized Interest, Operating and Investing Activities	315	157
Income Taxes Paid, Net	179	142
Real Estate Owned, Transfer to Real Estate Owned	7	6
Transfer of Portfolio Loans and Leases to Held-for-sale	$ 63	$ 38