Consolidated Statement of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Activities
Net income	$ 5,388	$ 3,985	$ 4,143
Adjustments to reconcile net income to net cash provided (used) by operating activities
Provision for credit losses	441	433	255
Depreciation and amortization	1,117	1,193	1,088
Deferred income taxes	(403)	326	404
Changes in fair value of mortgage servicing rights	323	179	274
Gain on sales of Visa Class B common shares		(126)	(169)
Undistributed earnings of BlackRock	(727)	(361)	(407)
Net change in
Trading securities and other short-term investments	305	(1,167)	203
Loans held for sale	(1,148)	(935)	393
Other assets	757	(644)	1,568
Accrued expenses and other liabilities	(704)	652	(1,788)
Other	350	100	(439)
Net cash provided (used) by operating activities	5,699	3,635	5,525
Sales
Securities available for sale	5,647	3,456	6,723
Loans	2,001	1,897	2,040
Repayments/maturities
Securities available for sale	10,734	11,061	7,920
Securities held to maturity	2,948	3,209	2,032
Purchases
Securities available for sale	(13,605)	(19,495)	(26,367)
Securities held to maturity	(5,605)	(4,305)	(4,896)
Loans	(841)	(1,334)	(748)
Net change in
Federal funds sold and resale agreements	(245)	126	481
Interest-earning deposits with banks	(2,884)	4,835	1,233
Loans	(10,483)	(5,940)	(3,972)
Net cash paid for acquisition	(1,342)
Other	(1,340)	(952)	(706)
Net cash provided (used) by investing activities	(15,015)	(7,442)	(16,260)
Net change in
Noninterest-bearing deposits	(264)	1,212	5,765
Interest-bearing deposits	8,255	7,367	10,812
Federal funds purchased and repurchase agreements	(148)	18	(1,733)
Commercial paper	100
Other borrowed funds	459	272	(9)
Sales/issuances
Federal Home Loan Bank borrowings	11,000	1,000	2,250
Bank notes and senior debt	7,062	5,601	8,173
Commercial paper			1,394
Other borrowed funds	427	165	694
Preferred stock		519
Common and treasury stock	132	151	139
Repayments/maturities
Federal Home Loan Bank borrowings	(7,512)	(3,559)	(2,147)
Bank notes and senior debt	(1,800)	(3,750)	(2,624)
Subordinated debt	(2,758)	(488)	(524)
Commercial paper		(14)	(6,219)
Other borrowed funds	(318)	(541)	(1,622)
Preferred stock redemption			(500)
Redemption of noncontrolling interests	(1,000)
Acquisition of treasury stock	(2,447)	(2,062)	(2,152)
Preferred stock cash dividends paid	(236)	(209)	(219)
Common stock cash dividends paid	(1,266)	(1,061)	(1,038)
Net cash provided (used) by financing activities	9,686	4,621	10,440
Net Increase (Decrease) In Cash And Due From Banks	370	814	(295)
Cash and due from banks at beginning of period	4,879	4,065	4,360
Cash and due from banks at end of period	5,249	4,879	4,065
Supplemental Disclosures
Interest paid	1,743	1,317	1,005
Income taxes paid	72	658	919
Income taxes refunded	24	111	286
Non-cash Investing and Financing Items
Transfer from loans to loans held for sale, net	419	606	285
Transfer from loans to foreclosed assets	215	281	435
Transfer from trading securities to investment securities	$ 192