Comerica (CMA) 10-Q 30 Oct 19 2019 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2019	Oct. 25, 2019
Document And Entity Information [Abstract]
Document Quarterly Report	true
Title of 12(b) Security	Common Stock, $5 par value
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	38-1998421
Document Type	10-Q
Document Period End Date	Sep. 30, 2019
Amendment Flag	false
Entity Registrant Name	Comerica Incorporated
Entity Central Index Key	0000028412
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		144,154,334
Entity File Number	1-10706
Entity Shell Company	false
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Address, Address Line One	1717 Main Street, MC 6404
Entity Address, City or Town	Dallas
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	75201
City Area Code	(214)
Local Phone Number	462-6831
Document Transition Report	false
Trading Symbol	CMA
Security Exchange Name	NYSE

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
ASSETS
Cash and due from banks	$ 1,229	$ 1,390
Interest-bearing deposits with banks	2,888	3,171
Other short-term investments	146	134
Investment securities available-for-sale	12,429	12,045
Commercial loans	32,890	31,976
Real estate construction loans	3,377	3,077
Commercial mortgage loans	9,234	9,106
Lease financing	578	507
International loans	1,055	1,013
Residential mortgage loans	1,906	1,970
Consumer loans	2,451	2,514
Total loans	51,491	50,163
Less allowance for loan losses	(652)	(671)
Net loans	50,839	49,492
Premises and equipment	467	475
Accrued income and other assets	4,850	4,111
Total assets	72,848	70,818
LIABILITIES AND SHAREHOLDERS' EQUITY
Noninterest-bearing deposits	27,134	28,690
Money market and interest-bearing checking deposits	23,992	22,560
Savings deposits	2,156	2,172
Customer certificates of deposit	2,853	2,131
Other time deposits	647	0
Foreign office time deposits	27	8
Total interest-bearing deposits	29,675	26,871
Total deposits	56,809	55,561
Short-term borrowings	51	44
Accrued expenses and other liabilities	1,477	1,243
Medium- and long-term debt	7,311	6,463
Total liabilities	65,648	63,311
Common stock - $5 par value: Authorized - 325,000,000 shares; Issued - 228,164,824 shares	1,141	1,141
Capital surplus	2,172	2,148
Accumulated other comprehensive loss	(336)	(609)
Retained earnings	9,369	8,781
Less cost of common stock in treasury - 78,367,534 shares at 6/30/19 and 68,081,176 shares at 12/31/18	(5,146)	(3,954)
Total shareholders' equity	7,200	7,507
Total liabilities and shareholders' equity	$ 72,848	$ 70,818

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Common stock, par value	$ 5	$ 5
Common stock, authorized shares	325,000,000	325,000,000
Common stock, issued shares	228,164,824	228,164,824
Shares in treasury	84,028,400	68,081,176

Consolidated Statements Of Comp

Consolidated Statements Of Comprehensive Income - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
INTEREST INCOME
Interest and fees on loans		$ 619	$ 581	$ 1,875	$ 1,658
Interest on investment securities		75	66	222	194
Interest on short-term investments		17	28	51	63
Total interest income		711	675	2,148	1,915
INTEREST EXPENSE
Interest on deposits		73	35	192	79
Interest on short-term borrowings		2	1	9	1
Interest on medium- and long-term debt	[1]	50	40	152	97
Total interest expense		125	76	353	177
Net interest income		586	599	1,795	1,738
Provision for credit losses		35	0	66	(17)
Net interest income after provision for credit losses		551	599	1,729	1,755
NONINTEREST INCOME
Card Fees		67	61	195	180
Service charges on deposit accounts		51	53	153	160
Fiduciary income		53	51	154	155
Commercial lending fees		23	21	66	62
Foreign exchange income		11	12	33	36
Letter of credit fees		10	9	29	30
Bank-owned life insurance		11	11	31	29
Brokerage fees		7	7	21	20
Net securities gains (losses)		0	(20)	(8)	(19)
Other noninterest income		23	29	70	73
Total noninterest income		256	234	744	726
NONINTEREST EXPENSES
Salaries and benefits expense		253	254	763	759
Outside processing fee expense		66	65	194	190
Net occupancy expense		39	38	113	113
Software expense		30	32	87	95
Equipment expense		13	12	37	34
FDIC insurance expense		6	11	17	36
Advertising expense		10	8	24	22
Restructuring charges		0	12	0	39
Other noninterest expenses		18	20	57	58
Total noninterest expenses		435	452	1,292	1,346
Income before income taxes		372	381	1,181	1,135
Provision for income taxes		80	63	252	210
Net income (loss)		292	318	929	925
Less income allocated to participating securities		2	2	5	6
Net income attributable to shares		$ 290	$ 316	$ 924	$ 919
Basic earnings per share		$ 1.98	$ 1.89	$ 6.08	$ 5.41
Diluted earnings per share		$ 1.96	$ 1.86	$ 6.02	$ 5.32
Comprehensive income		$ 338	$ 296	$ 1,202	$ 764
Cash dividends declared on stock		$ 97	$ 100	$ 302	$ 210
Cash dividends declared per share		$ 0.67	$ 0.60	$ 2.01	$ 1.24
[1]	Includes the effects of hedging.

Consolidated Statements Of Chan

Consolidated Statements Of Changes In Shareholders' Equity - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Capital Surplus	Accumulated Other Comprehensive Loss	Retained Earnings	Treasury Stock
Cumulative effect of change in accounting principle	$ 15			$ 1	$ 14
BALANCE (in shares) at Dec. 31, 2017		172.9
BALANCE at Dec. 31, 2017	7,963	$ 1,141	$ 2,122	(451)	7,887	$ (2,736)
Net income	925				925
Other comprehensive income (loss), net of tax	(161)			(161)
Cash dividends declared on stock	(210)				(210)
Purchase of common stock	(828)		(7)			(821)
Purchase of common stock (in shares)		(8.7)
Net issuance of common stock under employee stock plans	41		(9)		(24)	74
Net issuance of common stock under employee stock plans (in shares)		1.5
Net issuance of common stock for warrants	0		(3)		(5)	8
Net issuance of common stock for warrants (in shares)		0.2
Share-based compensation	41		41
BALANCE at Sep. 30, 2018	7,786	$ 1,141	2,144	(611)	8,587	(3,475)
BALANCE (in shares) at Sep. 30, 2018		165.9
BALANCE (in shares) at Jun. 30, 2018		170.9
BALANCE at Jun. 30, 2018	8,079	$ 1,141	2,144	(589)	8,374	(2,991)
Net income	318				318
Other comprehensive income (loss), net of tax	(22)			(22)
Cash dividends declared on stock	(100)				(100)
Purchase of common stock	(500)		(7)			(493)
Purchase of common stock (in shares)		(5.3)
Net issuance of common stock under employee stock plans	4		2		(3)	5
Net issuance of common stock under employee stock plans (in shares)		0.2
Net issuance of common stock for warrants	0		(2)		(2)	4
Net issuance of common stock for warrants (in shares)		0.1
Share-based compensation	7		7
BALANCE at Sep. 30, 2018	7,786	$ 1,141	2,144	(611)	8,587	(3,475)
BALANCE (in shares) at Sep. 30, 2018		165.9
Cumulative effect of change in accounting principle	(14)				(14)
BALANCE (in shares) at Dec. 31, 2018		160.1
BALANCE at Dec. 31, 2018	7,507	$ 1,141	2,148	(609)	8,781	(3,954)
Net income	929				929
Other comprehensive income (loss), net of tax	273			273
Cash dividends declared on stock	(302)				(302)
Purchase of common stock	(1,229)		0			(1,229)
Purchase of common stock (in shares)		(16.6)
Net issuance of common stock under employee stock plans	(1)		(13)		(25)	37
Net issuance of common stock under employee stock plans (in shares)		0.6
Share-based compensation	37		37
BALANCE at Sep. 30, 2019	7,200	$ 1,141	2,172	(336)	9,369	(5,146)
BALANCE (in shares) at Sep. 30, 2019		144.1
BALANCE (in shares) at Jun. 30, 2019		149.8
BALANCE at Jun. 30, 2019	7,323	$ 1,141	2,168	(382)	9,176	(4,780)
Net income	292				292
Other comprehensive income (loss), net of tax	46			46
Cash dividends declared on stock	(97)				(97)
Purchase of common stock	(370)		0			(370)
Purchase of common stock (in shares)		(5.7)
Net issuance of common stock under employee stock plans	1		(1)		(2)	4
Share-based compensation	5		5
BALANCE at Sep. 30, 2019	$ 7,200	$ 1,141	$ 2,172	$ (336)	$ 9,369	$ (5,146)
BALANCE (in shares) at Sep. 30, 2019		144.1

Consolidated Statements Of Ch_2

Consolidated Statements Of Changes In Shareholders' Equity (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Stockholders' Equity [Abstract]
Cash dividends declared on stock, per share	$ 0.67	$ 0.60	$ 2.01	$ 1.24

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
OPERATING ACTIVITIES
Net income	$ 929	$ 925
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for credit losses	66	(17)
(Benefit) provision for deferred income taxes	4	37
Depreciation and amortization	84	90
Net periodic defined benefit credit	(23)	(14)
Share-based compensation expense	37	41
Net amortization of securities	2	3
Accretion Of Discount On Receivables Acquired In Transfer	0	(1)
Net securities (losses) gains	8	19
Net gains on sales of foreclosed property	0	(1)
Net change in accrued income receivable	1	(36)
Net change in accrued expenses payable	(39)	19
Other, net	(200)	(98)
Net cash provided by operating activities	869	967
INVESTING ACTIVITIES
Maturities and redemptions of investment securities available-for-sale	1,615	1,366
Sales of investment securities available-for-sale	987	1,256
Purchases of investment securities available-for-sale	(2,721)	(2,618)
Net change in loans	(1,419)	120
Proceeds from sales of foreclosed property	1	7
Net increase in premises and equipment	(62)	(65)
Purchases of Federal Home Loan Bank stock	(201)	(41)
Proceeds from Sale of Federal Home Loan Bank Stock	201	0
Proceeds from bank-owned life insurance settlements	7	4
Other, net	2	(2)
Net cash (used in) provided by investing activities	(1,590)	27
FINANCING ACTIVITIES
Net change in deposits	1,105	(1,978)
Net change in short-term borrowings	7	74
Maturities of medium- and long-term debt	(350)	0
Issuances and advances of medium- and long-term debt	1,050	1,850
Repurchases of common stock	(1,242)	(837)
Cash dividends paid on common stock	(303)	(161)
Issuances of common stock under employee stock plans	12	50
Other, net	(2)	2
Net cash provided by (used in) financing activities	277	(1,000)
Net decrease in cash and cash equivalents	(444)	(6)
Cash and cash equivalents at beginning of period	4,561	5,845
Cash and cash equivalents at end of period	4,117	5,839
Interest paid	347	172
Income tax paid	221	125
Noncash investing and financing activities:
Loans transferred to other real estate	3	2
Securities transferred from held-to-maturity to available-for-sale	0	1,266
Securities transferred from available-for-sale to equity securities	$ 0	$ 81

Basis of Presentation and Accou

Basis of Presentation and Accounting Policies	9 Months Ended
	Sep. 30, 2019
Accounting Policies [Abstract]
Basis of Presentation and Accounting Policies	BASIS OF PRESENTATION AND ACCOUNTING POLICIES Organization The accompanying unaudited consolidated financial statements were prepared in accordance with United States (U.S.) generally accepted accounting principles (GAAP) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, the statements do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation were included. The results of operations for the nine months ended September 30, 2019 are not necessarily indicative of the results that may be expected for the year ending December 31, 2019 . Certain items in prior periods were reclassified to conform to the current presentation. For further information, refer to the consolidated financial statements and footnotes thereto included in the Annual Report of Comerica Incorporated and Subsidiaries (the Corporation) on Form 10-K for the year ended December 31, 2018 . Leases Effective January 1, 2019, the Corporation adopted the provisions of Accounting Standards Update (ASU) No. 2016-02, “Leases (Topic 842),” (ASU 2016-02), for all open leases with a term greater than one year as of the adoption date, using the modified retrospective approach. Prior comparable periods are presented in accordance with previous guidance under Accounting Standards Codification (ASC) 840, “Leases.” Topic 842 requires the recognition of a lease liability, measured as the present value of unpaid lease payments for operating leases where the Corporation is the lessee, and a corresponding right-of-use (ROU) asset for the right to use the leased properties. The Corporation elected not to reassess whether contracts are or contain leases, lease classification or initial direct costs for existing leases, a set of practical expedients for transition provided by ASU 2016-12. Further, the Corporation elected the practical expedient to use hindsight in determining the lease term and assessing impairment. The election of the hindsight practical expedient resulted in longer lease terms for a limited number of strategic locations based on relevant factors as of the adoption date. The impact at adoption was increases of $329 million and $343 million to total assets and liabilities, respectively, and a $14 million reduction to retained earnings. The increase in total assets was due to the recognition of ROU assets recorded in accrued income and other assets, and the increase in total liabilities was due to corresponding recognition of lease payment liabilities recorded in accrued expenses and other liabilities. Operating lease liabilities reflect the Corporation’s obligation to make future lease payments, primarily for real estate locations. Lease terms typically comprise contractual terms but may include extension options reasonably certain of being exercised at lease inception for certain strategic locations such as regional headquarters. Payments are discounted using the rate the Corporation would pay to borrow amounts equal to the lease payments over the lease term (the Corporation’s incremental borrowing rate). The Corporation does not separate lease and non-lease components for contracts in which it is the lessee. ROU assets are measured based on lease liabilities adjusted for incentives as well as accrued and prepaid rent. Operating lease expense is recognized on a straight-line basis over the lease term, while variable lease payments are recognized as incurred. Common area maintenance and other executory costs are the main components of variable lease payments. Operating and variable lease expenses are recorded in net occupancy expense in the Consolidated Statements of Income. The Corporation is the lessor in sales-type, direct finance and leveraged lease arrangements. Leases are recorded at the principal balance outstanding, net of unearned income and charge-offs. Interest income is recognized using the interest method. The impact of adopting Topic 842 for lessor accounting was not significant. Pending Accounting Pronouncements In June 2016, the FASB issued ASU No. 2016-13, "Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments," (ASU 2016-13), which addresses concerns regarding the perceived delay in recognition of credit losses under the existing incurred loss model. The amendment introduces a new, single model for recognizing credit losses on all financial instruments presented on a cost basis. Under the new model, entities must estimate current expected credit losses by considering all available relevant information, including historical and current conditions, as well as reasonable and supportable forecasts of future events. ASU 2016-13 also requires additional qualitative and quantitative disclosure to allow users to better understand the credit risk within the portfolio and the methodologies for determining the allowance for credit losses. ASU 2016-13 is effective for the Corporation on January 1, 2020 and must generally be applied using the modified retrospective approach with a cumulative effect adjustment to retained earnings. In prior periods, the Corporation developed and completed internal validations of new credit estimation models. The Corporation has implemented new processes and controls for the execution of the new model and is in the process of testing them. The implementation team continues to challenge current model assumptions and outputs, refine the qualitative framework and finalize policies and disclosures. Additionally, parallel runs will continue in fourth quarter 2019 as more end-to-end processes, controls and policies are fina lized. Incorporating reasonable and supportable forecasts of economic conditions into the estimate of expected credit losses will require significant judgment, such as selecting economic variables and forecast scenarios as well as determining the appropriate length of the forecast horizon. Management will select economic variables it believes to be most relevant based on the composition of the loan portfolio and customer base, likely to include forecasted levels of employment, gross domestic product, corporate bond and treasury spreads, industrial production levels, consumer and commercial real estate price indices as well as housing statistics. Different economic forecasts ranging from more benign to more severe will be evaluated each reporting period to forecast losses over the contractual life of the loan portfolio. The Corporation anticipates using a two-year forecast horizon, which encompasses most of the remaining contractual life of its portfolio of commercial loans, reverting to its longer-term historical loss experience to estimate expected losses over any remaining contractual life. The ultimate impact of ASU 2016-13 will depend on the composition of the portfolio as well as economic conditions and forecasts at the time of adoption. Based on current factors, the Corporation estimates overall allowance for credit losses to remain within 5 percent of current levels. The commercial portfolio, comprising the majority of the Corporation’s portfolio, consists of loans and lending arrangements with short contractual maturities that are expected to result in a reduction of up to 5 percent in the allowance for credit losses. The allowance for credit losses is expected to increase between 60 to 80 percent for the consumer portfolio given its longer contractual maturities. ASU 2016-13 also requires expected credit losses on available-for-sale securities (AFS) debt securities be recorded as an allowance for credit losses. For certain types of debt securities, such as U.S. Treasuries and other securities with government guarantees, entities may expect zero credit losses. The Corporation believes the zero-loss expectation currently applies to all of its AFS securities. ASU 2016-13 will be adopted in first quarter 2020.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	FAIR VALUE MEASUREMENTS The Corporation utilizes fair value measurements to record fair value adjustments to certain assets and liabilities and to determine fair value disclosures. The determination of fair values of financial instruments often requires the use of estimates. In cases where quoted market values in an active market are not available, the Corporation uses present value techniques and other valuation methods to estimate the fair values of its financial instruments. These valuation methods require considerable judgment and the resulting estimates of fair value can be significantly affected by the assumptions made and methods used. Equity securities, investment securities available-for-sale, derivatives and deferred compensation plan assets and liabilities are recorded at fair value on a recurring basis. Additionally, from time to time, the Corporation may be required to record other assets and liabilities at fair value on a nonrecurring basis, such as impaired loans, other real estate (primarily foreclosed property), nonmarketable equity securities and certain other assets and liabilities. These nonrecurring fair value adjustments typically involve write-downs of individual assets or application of lower of cost or fair value accounting. Refer to Note 1 to the consolidated financial statements in the Corporation's Annual Report on Form 10-K for the year ended December 31, 2018 for further information about the fair value hierarchy, descriptions of the valuation methodologies and key inputs used to measure financial assets and liabilities recorded at fair value, as well as a description of the methods and significant assumptions used to estimate fair value disclosures for financial instruments not recorded at fair value in their entirety on a recurring basis. Assets and Liabilities Recorded at Fair Value on a Recurring Basis The following tables present the recorded amount of assets and liabilities measured at fair value on a recurring basis as of September 30, 2019 and December 31, 2018 . (in millions) Total Level 1 Level 2 Level 3 September 30, 2019 Deferred compensation plan assets $ 92 $ 92 $ — $ — Equity securities 49 49 — — Investment securities available-for-sale: U.S. Treasury and other U.S. government agency securities 2,796 2,796 — — Residential mortgage-backed securities (a) 9,633 — 9,633 — Total investment securities available-for-sale 12,429 2,796 9,633 — Derivative assets: Interest rate contracts 275 — 247 28 Energy derivative contracts 160 — 160 — Foreign exchange contracts 13 — 13 — Total derivative assets 448 — 420 28 Total assets at fair value $ 13,018 $ 2,937 $ 10,053 $ 28 Derivative liabilities: Interest rate contracts $ 43 $ — $ 43 $ — Energy derivative contracts 156 — 156 — Foreign exchange contracts 10 — 10 — Total derivative liabilities 209 — 209 — Deferred compensation plan liabilities 92 92 — — Total liabilities at fair value $ 301 $ 92 $ 209 $ — December 31, 2018 Deferred compensation plan assets $ 88 $ 88 $ — $ — Equity securities 43 43 — — Investment securities available-for-sale: U.S. Treasury and other U.S. government agency securities 2,727 2,727 — — Residential mortgage-backed securities (a) 9,318 — 9,318 — Total investment securities available-for-sale 12,045 2,727 9,318 — Derivative assets: Interest rate contracts 67 — 58 9 Energy derivative contracts 189 — 189 — Foreign exchange contracts 19 — 19 — Total derivative assets 275 — 266 9 Total assets at fair value $ 12,451 $ 2,858 $ 9,584 $ 9 Derivative liabilities: Interest rate contracts $ 70 $ — $ 70 $ — Energy derivative contracts 186 — 186 — Foreign exchange contracts 13 — 13 — Total derivative liabilities 269 — 269 — Deferred compensation plan liabilities 88 88 — — Total liabilities at fair value $ 357 $ 88 $ 269 $ — (a) Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises. There were no transfers of assets or liabilities recorded at fair value on a recurring basis into or out of Level 1, Level 2 and Level 3 fair value measurements during each of the three- and nine-month periods ended September 30, 2019 and 2018 . The following table summarizes the changes in Level 3 assets and liabilities measured at fair value on a recurring basis for the three- and nine-month periods ended September 30, 2019 and 2018 . Net Realized/Unrealized Gains (Losses) (Pretax) Recorded in Earnings (b) Balance at Beginning of Period Change in Classification (a) Balance at End of Period Payments, Sales and Redemptions (in millions) Realized Unrealized Three Months Ended September 30, 2019 Derivative assets: Interest rate contracts $ 21 $ — $ 1 $ 7 $ (1 ) $ 28 Three Months Ended September 30, 2018 Derivative assets: Interest rate contracts $ 6 $ — $ — $ (4 ) $ — $ 2 Nine Months Ended September 30, 2019 Derivative assets: Interest rate contracts $ 9 — 1 19 (1 ) 28 Nine Months Ended September 30, 2018 Equity securities $ — $ 44 $ — $ — $ (44 ) $ — Investment securities available-for-sale: State and municipal securities (c) 5 — — — (5 ) — Equity and other non-debt securities (c) 44 (44 ) — — — — Total investment securities available-for-sale 49 (44 ) — — (5 ) — Derivative assets: Interest rate contracts 14 — — (12 ) — 2 (a) Reflects the reclassification of equity securities resulting from the adoption of ASU 2016-01. (b) Realized and unrealized gains and losses due to changes in fair value are recorded in other noninterest income on the Consolidated Statements of Comprehensive Income. (c) Auction-rate securities. Assets and Liabilities at Fair Value on a Nonrecurring Basis The Corporation may be required to record certain assets and liabilities at fair value on a nonrecurring basis. These include assets that are recorded at the lower of cost or fair value, and were recognized at fair value since it was less than cost at the end of the period. The following table presents assets recorded at fair value on a nonrecurring basis at September 30, 2019 and December 31, 2018 . No liabilities were recorded at fair value on a nonrecurring basis at September 30, 2019 and December 31, 2018 . (in millions) Level 3 September 30, 2019 Loans: Commercial $ 25 Total assets at fair value $ 25 December 31, 2018 Loans: Commercial $ 33 Commercial mortgage 2 Total assets at fair value $ 35 Level 3 assets recorded at fair value on a nonrecurring basis at September 30, 2019 and December 31, 2018 included loans for which a specific allowance was established based on the fair value of collateral. The unobservable inputs were the additional adjustments applied by management to the appraised values to reflect such factors as non-current appraisals and revisions to estimated time to sell. These adjustments are determined based on qualitative judgments made by management on a case-by-case basis and are not quantifiable inputs, although they are used in the determination of fair value. Estimated Fair Values of Financial Instruments Not Recorded at Fair Value on a Recurring Basis The Corporation typically holds the majority of its financial instruments until maturity and thus does not expect to realize many of the estimated fair value amounts disclosed. The disclosures also do not include estimated fair value amounts for items that are not defined as financial instruments, but which have significant value. These include such items as core deposit intangibles, the future earnings potential of significant customer relationships and the value of trust operations and other fee generating businesses. The Corporation believes the imprecision of an estimate could be significant. The carrying amount and estimated fair value of financial instruments not recorded at fair value in their entirety on a recurring basis on the Corporation’s Consolidated Balance Sheets are as follows: Carrying Amount Estimated Fair Value (in millions) Total Level 1 Level 2 Level 3 September 30, 2019 Assets Cash and due from banks $ 1,229 $ 1,229 $ 1,229 $ — $ — Interest-bearing deposits with banks 2,888 2,888 2,888 — — Loans held-for-sale 4 4 — 4 — Total loans, net of allowance for loan losses (a) 50,839 51,008 — — 51,008 Customers’ liability on acceptances outstanding 2 2 2 — — Restricted equity investments 248 248 248 — — Nonmarketable equity securities (b) 6 10 — — — Liabilities Demand deposits (noninterest-bearing) 27,134 27,134 — 27,134 — Interest-bearing deposits 26,175 26,175 — 26,175 — Customer certificates of deposit 2,853 2,842 — 2,842 — Other time deposits 647 647 — 647 — Total deposits 56,809 56,798 — 56,798 — Short-term borrowings 51 51 51 — — Acceptances outstanding 2 2 2 — — Medium- and long-term debt 7,311 7,316 — 7,316 — Credit-related financial instruments (56 ) (56 ) — — (56 ) December 31, 2018 Assets Cash and due from banks $ 1,390 $ 1,390 $ 1,390 $ — $ — Interest-bearing deposits with banks 3,171 3,171 3,171 — — Loans held-for-sale 3 3 — 3 — Total loans, net of allowance for loan losses (a) 49,492 48,889 — — 48,889 Customers’ liability on acceptances outstanding 4 4 4 — — Restricted equity investments 248 248 248 — — Nonmarketable equity securities (b) 6 11 Liabilities Demand deposits (noninterest-bearing) 28,690 28,690 — 28,690 — Interest-bearing deposits 24,740 24,740 — 24,740 — Certificates of deposit 2,131 2,100 — 2,100 — Total deposits 55,561 55,530 — 55,530 — Short-term borrowings 44 44 44 — — Acceptances outstanding 4 4 4 — — Medium- and long-term debt 6,463 6,436 — 6,436 — Credit-related financial instruments (57 ) (57 ) — — (57 ) (a) Included $25 million and $35 million of impaired loans recorded at fair value on a nonrecurring basis at September 30, 2019 and December 31, 2018 , respectively. (b) Certain investments that are measured at fair value using the net asset value have not been classified in the fair value hierarchy. The fair value amounts presented in the table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the Consolidated Balance Sheets.

Investment Securities

Investment Securities	9 Months Ended
	Sep. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Investment Securities	INVESTMENT SECURITIES A summary of the Corporation’s investment securities follows: (in millions) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value September 30, 2019 Investment securities available-for-sale: U.S. Treasury and other U.S. government agency securities $ 2,744 $ 52 $ — $ 2,796 Residential mortgage-backed securities (a) 9,590 74 31 9,633 Total investment securities available-for-sale $ 12,334 $ 126 $ 31 $ 12,429 December 31, 2018 Investment securities available-for-sale: U.S. Treasury and other U.S. government agency securities $ 2,732 $ 14 $ 19 $ 2,727 Residential mortgage-backed securities (a) 9,493 22 197 9,318 Total investment securities available-for-sale $ 12,225 $ 36 $ 216 $ 12,045 (a) Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises. A summary of the Corporation’s investment securities in an unrealized loss position as of September 30, 2019 and December 31, 2018 follows: Temporarily Impaired Less than 12 Months 12 Months or more Total (in millions) Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses September 30, 2019 Residential mortgage-backed securities (a) $ 1,412 $ 4 $ 2,130 $ 27 $ 3,542 $ 31 Total temporarily impaired securities $ 1,412 $ 4 $ 2,130 $ 27 $ 3,542 $ 31 December 31, 2018 U.S. Treasury and other U.S. government agency securities $ — $ — $ 1,457 $ 19 $ 1,457 $ 19 Residential mortgage-backed securities (a) 1,008 9 6,412 188 7,420 197 Total temporarily impaired securities $ 1,008 $ 9 $ 7,869 $ 207 $ 8,877 $ 216 (a) Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises. At September 30, 2019 , the Corporation had 178 residential mortgage-backed securities in an unrealized loss position with no credit impairment. The unrealized losses for these securities resulted from changes in market interest rates and liquidity, not changes in credit quality. The Corporation ultimately expects full collection of the carrying amount of these securities, does not intend to sell the securities in an unrealized loss position, and it is not more-likely-than-not that the Corporation will be required to sell the securities in an unrealized loss position prior to recovery of amortized cost. The Corporation does not consider these securities to be other-than-temporarily impaired at September 30, 2019 . Sales, calls and write-downs of investment securities available-for-sale resulted in the following gains and losses recorded in net securities losses on the Consolidated Statements of Comprehensive Income, computed based on the adjusted cost of the specific security. Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2019 2018 2019 2018 Securities gains $ — $ — $ — $ 1 Securities losses — (20 ) (8 ) (20 ) Net securities $ — $ (20 ) $ (8 ) $ (19 ) The following table summarizes the amortized cost and fair values of debt securities by contractual maturity. Securities with multiple maturity dates are classified in the period of final maturity. Expected maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. (in millions) September 30, 2019 Amortized Cost Fair Value Contractual maturity Within one year $ 30 $ 31 After one year through five years 2,818 2,874 After five years through ten years 1,127 1,134 After ten years 8,359 8,390 Total investment securities $ 12,334 $ 12,429 Included in the contractual maturity distribution in the table above were residential mortgage-backed securities with total amortized cost and fair value of $9.6 billion . The actual cash flows of mortgage-backed securities may differ as borrowers of the underlying loans may exercise prepayment options. At September 30, 2019 , investment securities with a carrying value of $375 million were pledged where permitted or required by law to secure $270 million of liabilities, primarily public and other deposits of state and local government agencies as well as derivative instruments.

Credit Quality And Allowance Fo

Credit Quality And Allowance For Credit Losses	9 Months Ended
	Sep. 30, 2019
Credit Quality And Allowance For Credit Losses [Abstract]
Credit Quality And Allowance For Credit Losses	During the twelve-month periods ended September 30, 2019 and 2018 , loans with a carrying value of $1 million and $3 million , respectively, were modified by interest rate reduction (reduced-rate loans). For principal deferrals, incremental deterioration in the credit quality of the loan, represented by a downgrade in the risk rating of the loan, for example, due to missed interest payments or a reduction of collateral value, is considered a subsequent default. For interest rate reductions, a subsequent payment default is defined in terms of delinquency, when a principal or interest payment is 90 days past due. Subsequent defaults of principal deferrals totaled $17 million in the three- and nine-month periods ended September 30, 2019 and none in the comparable periods in 2018 . There were no subsequent defaults of interest rate reductions during either the three- and nine-month periods ended September 30, 2019 and 2018

Derivative And Credit-Related F

Derivative And Credit-Related Financial Instruments	9 Months Ended
	Sep. 30, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative And Credit-Related Financial Instruments	DERIVATIVE AND CREDIT-RELATED FINANCIAL INSTRUMENTS In the normal course of business, the Corporation enters into various transactions involving derivative and credit-related financial instruments to manage exposure to fluctuations in interest rate, foreign currency and other market risks and to meet the financing needs of customers (customer-initiated derivatives). These financial instruments involve, to varying degrees, elements of market and credit risk. Market and credit risk are included in the determination of fair value. Market risk is the potential loss that may result from movements in interest rates, foreign currency exchange rates or energy commodity prices that cause an unfavorable change in the value of a financial instrument. The Corporation manages this risk by establishing monetary exposure limits and monitoring compliance with those limits. Market risk inherent in interest rate and energy contracts entered into on behalf of customers is mitigated by taking offsetting positions, except in those circumstances when the amount, tenor and/or contract rate level results in negligible economic risk, whereby the cost of purchasing an offsetting contract is not economically justifiable. The Corporation mitigates most of the inherent market risk in foreign exchange contracts entered into on behalf of customers by taking offsetting positions and manages the remainder through individual foreign currency position limits and aggregate value-at-risk limits. These limits are established annually and positions are monitored quarterly. Market risk inherent in derivative instruments held or issued for risk management purposes is typically offset by changes in the fair value of the assets or liabilities being hedged. Credit risk is the possible loss that may occur in the event of nonperformance by the counterparty to a financial instrument. The Corporation attempts to minimize credit risk arising from customer-initiated derivatives by evaluating the creditworthiness of each customer, adhering to the same credit approval process used for traditional lending activities and obtaining collateral as deemed necessary. Derivatives with dealer counterparties are either cleared through a clearinghouse or settled directly with a single counterparty. For derivatives settled directly with dealer counterparties, the Corporation utilizes counterparty risk limits and monitoring procedures as well as master netting arrangements and bilateral collateral agreements to facilitate the management of credit risk. Master netting arrangements effectively reduce credit risk by permitting settlement of positive and negative positions and offset cash collateral held with the same counterparty on a net basis. Bilateral collateral agreements require daily exchange of cash or highly rated securities issued by the U.S. Treasury or other U.S. government entities to collateralize amounts due to either party. At September 30, 2019 , counterparties with bilateral collateral agreements pledged $1 million of marketable investment securities and deposited $102 million of cash with the Corporation to secure the fair value of contracts in an unrealized gain position, and the Corporation had pledged $27 million of marketable investment securities and posted $13 million of cash as collateral for contracts in an unrealized loss position. For those counterparties not covered under bilateral collateral agreements, collateral is obtained, if deemed necessary, based on the results of management’s credit evaluation of the counterparty. Collateral varies, but may include cash, investment securities, accounts receivable, equipment or real estate. Included in the fair value of derivative instruments are credit valuation adjustments reflecting counterparty credit risk. These adjustments are determined by applying a credit spread for the counterparty or the Corporation, as appropriate, to the total expected exposure of the derivative. There were no derivative instruments with credit-risk-related contingent features that were in a liability position at September 30, 2019 . Derivative Instruments Derivative instruments utilized by the Corporation are negotiated over-the-counter and primarily include swaps, caps and floors, forward contracts and options, each of which may relate to interest rates, energy commodity prices or foreign currency exchange rates. Swaps are agreements in which two parties periodically exchange cash payments based on specified indices applied to a specified notional amount until a stated maturity. Caps and floors are agreements which entitle the buyer to receive cash payments based on the difference between a specified reference rate or price and an agreed strike rate or price, applied to a specified notional amount until a stated maturity. Forward contracts are over-the-counter agreements to buy or sell an asset at a specified future date and price. Options are similar to forward contracts except the purchaser has the right, but not the obligation, to buy or sell the asset during a specified period or at a specified future date. Over-the-counter contracts are tailored to meet the needs of the counterparties involved and, therefore, contain a greater degree of credit risk and liquidity risk than exchange-traded contracts, which have standardized terms and readily available price information. The Corporation reduces exposure to market and liquidity risks from over-the-counter derivative instruments entered into for risk management purposes, and transactions entered into to mitigate the market risk associated with customer-initiated transactions, by taking offsetting positions with investment grade domestic and foreign financial institutions and subjecting counterparties to credit approvals, limits and collateral monitoring procedures similar to those used in making other extensions of credit. In addition, certain derivative contracts executed bilaterally with a dealer counterparty in the over-the-counter market are cleared through a clearinghouse, whereby the clearinghouse becomes the counterparty to the transaction. The following table presents the composition of the Corporation’s derivative instruments held or issued for risk management purposes or in connection with customer-initiated and other activities at September 30, 2019 and December 31, 2018 . The table excludes commitments and warrants accounted for as derivatives. September 30, 2019 December 31, 2018 Fair Value Fair Value (in millions) Notional/ Contract Amount (a) Gross Derivative Assets Gross Derivative Liabilities Notional/ Contract Amount (a) Gross Derivative Assets Gross Derivative Liabilities Risk management purposes Derivatives designated as hedging instruments Interest rate contracts: Swaps - fair value - receive fixed/pay floating $ 3,325 $ — $ — $ 2,625 $ — $ 2 Swaps - cash flow - receive fixed/pay floating 3,800 — — — — — Derivatives used as economic hedges Foreign exchange contracts: Spot, forwards and swaps 309 1 — 302 1 1 Total risk management purposes 7,434 1 — 2,927 1 3 Customer-initiated and other activities Interest rate contracts: Caps and floors written 912 — 1 885 — 1 Caps and floors purchased 912 1 — 885 1 — Swaps 15,687 274 42 13,115 66 67 Total interest rate contracts 17,511 275 43 14,885 67 68 Energy contracts: Caps and floors written 468 — 30 278 — 26 Caps and floors purchased 468 30 — 278 26 — Swaps 2,147 130 126 2,094 163 160 Total energy contracts 3,083 160 156 2,650 189 186 Foreign exchange contracts: Spot, forwards, options and swaps 1,061 12 10 1,095 18 12 Total customer-initiated and other activities 21,655 447 209 18,630 274 266 Total gross derivatives $ 29,089 $ 448 $ 209 $ 21,557 $ 275 $ 269 Amounts offset in the Consolidated Balance Sheets: Netting adjustment - Offsetting derivative assets/liabilities (45 ) (45 ) (45 ) (45 ) Netting adjustment - Cash collateral received/posted (101 ) (12 ) (174 ) (1 ) Net derivatives included in the Consolidated Balance Sheets (b) 302 152 56 223 Amounts not offset in the Consolidated Balance Sheets: Marketable securities pledged under bilateral collateral agreements (1 ) (26 ) (1 ) — Net derivatives after deducting amounts not offset in the Consolidated Balance Sheets $ 301 $ 126 $ 55 $ 223 (a) Notional or contractual amounts, which represent the extent of involvement in the derivatives market, are used to determine the contractual cash flows required in accordance with the terms of the agreement. These amounts are typically not exchanged, significantly exceed amounts subject to credit or market risk and are not reflected in the Consolidated Balance Sheets. (b) Net derivative assets are included in accrued income and other assets and net derivative liabilities are included in accrued expenses and other liabilities on the Consolidated Balance Sheets. Included in the fair value of net derivative assets and net derivative liabilities are credit valuation adjustments reflecting counterparty credit risk and credit risk of the Corporation. The fair value of net derivative assets included credit valuation adjustments for counterparty credit risk of $12 million and $2 million at September 30, 2019 and December 31, 2018 , respectively. Risk Management The Corporation's derivative instruments used for managing interest rate risk currently comprise swaps converting fixed-rate long-term debt to variable rates and variable-rate loans to fixed rates. The following table details the effects of fair value hedging on the Consolidated Statements of Comprehensive Income. Interest on Medium- and Long-Term Debt Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2019 2018 2019 2018 Total interest on medium-and long-term debt (a) $ 50 $ 40 $ 152 $ 97 Fair value hedging relationships: Interest rate contracts: Hedged items 28 21 80 51 Derivatives designated as hedging instruments (2 ) (1 ) (1 ) (7 ) (a) Includes the effects of hedging. For the impact of cash flow hedging, refer to Note 8. The following table summarizes the expected weighted average remaining maturity of the notional amount of risk management interest rate swaps, the carrying amount of the related hedged items and the weighted average interest rates associated with amounts expected to be received or paid on interest rate swap agreements as of September 30, 2019 and December 31, 2018 . Weighted Average (dollar amounts in millions) Derivative Notional Amount Carrying Value of Hedged Items (a) Remaining Maturity (in years) Receive Rate Pay Rate (b) September 30, 2019 Swaps - cash flow - receive fixed/pay floating rate Variable rate loans $ 3,800 3.3 2.04 2.07 Swaps - fair value - receive fixed/pay floating rate Medium- and long-term debt 3,325 $ 3,511 4.8 3.44 3.09 December 31, 2018 Swaps - fair value - receive fixed/pay floating rate Medium- and long-term debt 2,625 2,663 3.9 3.40 3.45 (a) Included $ 189 million and $ 49 million of cumulative hedging adjustments to fair value hedges at September 30, 2019 and December 31, 2018 , respectively, which included $ 7 million and $ 8 million , respectively, of hedging adjustment on a discontinued hedging relationship. (b) Variable rates paid on receive fixed swaps designated as fair value and cash flow hedges are based on one- and six-month LIBOR rates in effect at September 30, 2019 and December 31, 2018 . Foreign exchange rate risk arises from changes in the value of certain assets and liabilities denominated in foreign currencies. The Corporation employs spot and forward contracts in addition to swap contracts to manage exposure to these and other risks. These instruments are used as economic hedges and net gains or losses are included in other noninterest income in the Consolidated Statements of Comprehensive Income. Customer-Initiated and Other The Corporation enters into derivative transactions at the request of customers and generally takes offsetting positions with dealer counterparties to mitigate the inherent market risk. Income primarily results from the spread between the customer derivative and the offsetting dealer position. For customer-initiated foreign exchange contracts where offsetting positions have not been taken, the Corporation manages the remaining inherent market risk through individual foreign currency position limits and aggregate value-at-risk limits. These limits are established annually and reviewed quarterly. For those customer-initiated derivative contracts which were not offset or where the Corporation holds a position within the limits described above, the Corporation recognized no net gains or losses in other noninterest income in the Consolidated Statements of Comprehensive Income for both the three- and nine-month periods ended September 30, 2019 and 2018 . Fair values of customer-initiated and other derivative instruments represent the net unrealized gains or losses on such contracts and are recorded in the Consolidated Balance Sheets. Changes in fair value are recognized in the Consolidated Statements of Comprehensive Income. The net gains recognized in income on customer-initiated derivative instruments, net of the impact of offsetting positions, were as follows . Three Months Ended September 30, Nine Months Ended September 30, (in millions) Location of Gain 2019 2018 2019 2018 Interest rate contracts Other noninterest income $ 4 $ 9 $ 16 $ 20 Energy contracts Other noninterest income 1 1 4 1 Foreign exchange contracts Foreign exchange income 11 11 33 35 Total $ 16 $ 21 $ 53 $ 56 Credit-Related Financial Instruments The Corporation issues off-balance sheet financial instruments in connection with commercial and consumer lending activities. The Corporation’s credit risk associated with these instruments is represented by the contractual amounts indicated in the following table. (in millions) September 30, 2019 December 31, 2018 Unused commitments to extend credit: Commercial and other $ 23,280 $ 24,266 Bankcard, revolving check credit and home equity loan commitments 3,156 3,001 Total unused commitments to extend credit $ 26,436 $ 27,267 Standby letters of credit $ 3,281 $ 3,244 Commercial letters of credit 17 39 The Corporation maintains an allowance to cover probable credit losses inherent in lending-related commitments, including unused commitments to extend credit, letters of credit and financial guarantees. The allowance for credit losses on lending-related commitments, included in accrued expenses and other liabilities on the Consolidated Balance Sheets, was $29 million and $30 million at September 30, 2019 and December 31, 2018 , respectively. Unused Commitments to Extend Credit Commitments to extend credit are legally binding agreements to lend to a customer, provided there is no violation of any condition established in the contract. These commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since many commitments expire without being drawn upon, the total contractual amount of commitments does not necessarily represent future cash requirements of the Corporation. Commercial and other unused commitments are primarily variable rate commitments. The allowance for credit losses on lending-related commitments included $23 million at September 30, 2019 and $24 million at December 31, 2018 for probable credit losses inherent in the Corporation’s unused commitments to extend credit. Standby and Commercial Letters of Credit Standby letters of credit represent conditional obligations of the Corporation which guarantee the performance of a customer to a third party. Standby letters of credit are primarily issued to support public and private borrowing arrangements, including commercial paper, bond financing and similar transactions. Commercial letters of credit are issued to finance foreign or domestic trade transactions. These contracts expire in decreasing amounts through the year 2028 . The Corporation may enter into participation arrangements with third parties that effectively reduce the maximum amount of future payments which may be required under standby and commercial letters of credit. These risk participations covered $164 million and $136 million , respectively, of the $3.3 billion standby and commercial letters of credit outstanding at September 30, 2019 and December 31, 2018 . The carrying value of the Corporation’s standby and commercial letters of credit, included in accrued expenses and other liabilities on the Consolidated Balance Sheets, totaled $33 million at September 30, 2019 , including $27 million in deferred fees and $6 million in the allowance for credit losses on lending-related commitments. At December 31, 2018 , the comparable amounts were $34 million , $28 million and $6 million , respectively. The following table presents a summary of criticized standby and commercial letters of credit at September 30, 2019 and December 31, 2018 . The Corporation's criticized list is generally consistent with the Special Mention, Substandard and Doubtful categories defined by regulatory authorities. The Corporation manages credit risk through underwriting, periodically reviewing and approving its credit exposures using Board committee approved credit policies and guidelines. (dollar amounts in millions) September 30, 2019 December 31, 2018 Total criticized standby and commercial letters of credit $ 45 $ 49 As a percentage of total outstanding standby and commercial letters of credit 1.4 % 1.5 % Other Credit-Related Financial Instruments The Corporation enters into credit risk participation agreements, under which the Corporation assumes credit exposure associated with a borrower’s performance related to certain interest rate derivative contracts. The Corporation is not a party to the interest rate derivative contracts and only enters into these credit risk participation agreements in instances in which the Corporation is also a party to the related loan participation agreement for such borrowers. The Corporation manages its credit risk on the credit risk participation agreements by monitoring the creditworthiness of the borrowers, which is based on the normal credit review process had it entered into the derivative instruments directly with the borrower. The notional amount of such credit risk participation agreement reflects the pro-rata share of the derivative instrument, consistent with its share of the related participated loan. As of September 30, 2019 and December 31, 2018 , the total notional amount of the credit risk participation agreements was approximately $744 million and $703 million , respectively, and the fair value was insignificant for both periods. The maximum estimated exposure to these agreements, as measured by projecting a maximum value of the guaranteed derivative instruments, assuming 100 percent default by all obligors on the maximum values, was $26 million and $7 million at September 30, 2019 and December 31, 2018 , respectively. In the event of default, the lead bank has the ability to liquidate the assets of the borrower, in which case the lead bank would be required to return a percentage of the recouped assets to the participating banks. As of September 30, 2019 , the weighted average remaining maturity of outstanding credit risk participation agreements was 3.4 years.

Variable Interest Entities (VIE

Variable Interest Entities (VIEs)	9 Months Ended
	Sep. 30, 2019
Variable Interest Entity, Not Primary Beneficiary, Disclosures [Abstract]
Variable Interest Entities (VIEs)	VARIABLE INTEREST ENTITIES (VIEs) The Corporation evaluates its interest in certain entities to determine if these entities meet the definition of a VIE and whether the Corporation is the primary beneficiary and should consolidate the entity based on the variable interests it held both at inception and when there is a change in circumstances that requires a reconsideration. The Corporation holds ownership interests in funds in the form of limited partnerships or limited liability companies (LLCs) investing in affordable housing projects that qualify for the low-income housing tax credit (LIHTC). The Corporation also directly invests in limited partnerships and LLCs that invest in community development projects, which generate similar tax credits to investors (other tax credit entities). As an investor, the Corporation obtains income tax credits and deductions from the operating losses of these tax credit entities. These tax credit entities meet the definition of a VIE; however, the Corporation is not the primary beneficiary of the entities, as the general partner or the managing member has both the power to direct the activities that most significantly impact the economic performance of the entities and the obligation to absorb losses or the right to receive benefits that could be significant to the entities. The Corporation accounts for its interests in LIHTC entities using the proportional amortization method. Ownership interests in other tax credit entities are accounted for under either the cost or equity method. Exposure to loss as a result of the Corporation's involvement in LIHTC entities and other tax credit entities at September 30, 2019 was limited to $446 million and $6 million , respectively. Investment balances, including all legally binding commitments to fund future investments, are included in accrued income and other assets on the Consolidated Balance Sheets. A liability is recognized in accrued expenses and other liabilities on the Consolidated Balance Sheets for all legally binding unfunded commitments to fund tax credit entities ( $173 million at September 30, 2019 ). Amortization and other write-downs of LIHTC investments are presented on a net basis as a component of the provision for income taxes on the Consolidated Statements of Comprehensive Income, while amortization and write-downs of other tax credit investments are recorded in other noninterest income. The income tax credits and deductions are recorded as a reduction of income tax expense and a reduction of federal income taxes payable. The Corporation provided no financial or other support that was not contractually required to any of the above VIEs during the nine months ended September 30, 2019 and 2018 . The following table summarizes the impact of these tax credit entities on line items on the Corporation’s Consolidated Statements of Comprehensive Income. Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2019 2018 2019 2018 Other noninterest income: Amortization of other tax credit investments $ — $ — $ 1 $ 2 Provision for income taxes: Amortization of LIHTC investments 16 17 48 48 Low income housing tax credits (16 ) (16 ) (46 ) (46 ) Other tax benefits related to tax credit entities (3 ) (4 ) (10 ) (11 ) Total provision for income taxes $ (3 ) $ (3 ) $ (8 ) $ (9 ) For further information on the Corporation’s consolidation policy, see Note 1 to the consolidated financial statements in the Corporation's 2018 Annual Report.

Medium- And Long-Term Debt

Medium- And Long-Term Debt	9 Months Ended
	Sep. 30, 2019
Debt Disclosure [Abstract]
Medium- And Long-Term Debt	MEDIUM- AND LONG-TERM DEBT Medium- and long-term debt is summarized as follows: (in millions) September 30, 2019 December 31, 2018 Parent company Subordinated notes: 3.80% subordinated notes due 2026 (a) $ 269 $ 250 Medium- and long-term notes: 2.125% notes due 2019 (a) — 348 3.70% notes due 2023 (a) 892 861 4.00% notes due 2029 (a) 603 — Total medium- and long-term notes 1,495 1,209 Total parent company 1,764 1,459 Subsidiaries Subordinated notes: 4.00% subordinated notes due 2025 (a) 365 343 7.875% subordinated notes due 2026 (a) 207 198 Total subordinated notes 572 541 Medium- and long-term notes: 2.50% notes due 2020 (a) 672 663 2.50% notes due 2024 (a) 503 — Total medium- and long-term notes 1,175 663 Federal Home Loan Bank (FHLB) advances: Floating-rate based on FHLB auction rate due 2026 2,800 2,800 Floating-rate based on FHLB auction rate due 2028 1,000 1,000 Total FHLB advances 3,800 3,800 Total subsidiaries 5,547 5,004 Total medium- and long-term debt $ 7,311 $ 6,463 (a) The fixed interest rates on these notes have been swapped to a variable rate and designated in a hedging relationship. Accordingly, carrying value has been adjusted to reflect the change in the fair value of the debt as a result of changes in the benchmark rate. Subordinated notes with remaining maturities greater than one year qualify as Tier 2 capital. Comerica Bank (the Bank), a wholly-owned subsidiary of the Corporation, is a member of the FHLB, which provides short- and long-term funding to its members through advances collateralized by real estate-related assets. The interest rate on the FHLB advances resets between four and eight weeks, based on the FHLB auction rate. At September 30, 2019 , the weighted-average rate on the FHLB advances was 2.21% . Each note may be prepaid in full, without penalty, at each scheduled reset date. Borrowing capacity is contingent on the amount of collateral available to be pledged to the FHLB. At September 30, 2019 , $17.2 billion of real estate-related loans were pledged to the FHLB as collateral for current and potential future borrowings of approximately $5.1 billion . The Corporation issued $350 million of 4.00% senior notes maturing in 2029 , swapped to a floating rate at 30-day LIBOR plus 129 basis points in the first quarter 2019 and issued an additional $200 million of 4.00% senior notes maturing in 2029 in third quarter 2019, swapped to a floating rate at 30-day LIBOR plus 123 basis points. These notes were consolidated under a single series with an aggregate principal amount of $550 million . Also in third quarter 2019, the Bank issued $500 million of 2.50% medium-term notes due in 2024 , swapped to a floating rate based on 30-day LIBOR plus 84 basis points. Unamortized debt issuance costs deducted from the carrying amount of medium- and long-term debt totaled $13 million at September 30, 2019 and $8 million at December 31, 2018 .

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	9 Months Ended
	Sep. 30, 2019
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Loss	ACCUMULATED OTHER COMPREHENSIVE LOSS The following table presents a reconciliation of the changes in the components of accumulated other comprehensive loss and details the components of other comprehensive income (loss) for the nine months ended September 30, 2019 and 2018 , including the amount of income tax expense (benefit) allocated to each component of other comprehensive income (loss). Nine Months Ended September 30, (in millions) 2019 2018 Accumulated net unrealized gains (losses) on investment securities: Balance at beginning of period, net of tax $ (138 ) $ (101 ) Cumulative effect of change in accounting principle — 1 Net unrealized holding gains (losses) arising during the period 267 (254 ) Less: Provision (benefit) for income taxes 62 (59 ) Net unrealized holding gains (losses) arising during the period, net of tax 205 (195 ) Less: Net realized losses included in net securities losses (8 ) (20 ) Less: Benefit for income taxes (2 ) (5 ) Reclassification adjustment for net securities losses included in net income, net of tax (6 ) (15 ) Change in net unrealized gains (losses) on investment securities, net of tax 211 (180 ) Balance at end of period, net of tax $ 73 $ (280 ) Accumulated net gains on cash flow hedges: Balance at beginning of period, net of tax $ — $ — Net cash flow hedge gains arising during the period 69 — Less: Provision for income taxes 16 — Change in net cash flow hedge gains arising during the period, net of tax 53 — Less: Net cash flow hedge losses included in interest and fees on loans (1 ) — Change in net cash flow hedge gains, net of tax 54 — Balance at end of period, net of tax (a) $ 54 $ — Accumulated defined benefit pension and other postretirement plans adjustment: Balance at beginning of period, net of tax $ (471 ) $ (350 ) Amortization of actuarial net loss 30 45 Amortization of prior service credit (20 ) (20 ) Amounts recognized in other noninterest expense 10 25 Less: Provision for income taxes 2 6 Change in defined benefit pension and other postretirement plans adjustment, net of tax 8 19 Balance at end of period, net of tax $ (463 ) $ (331 ) Total accumulated other comprehensive loss at end of period, net of tax $ (336 ) $ (611 ) (a) The Corporation expects to reclassify $12 million of net gains, net of tax, from accumulated other comprehensive loss to earnings over the next twelve months if interest yield curves and notional amounts remain at September 30, 2019 levels.

Net Income Per Share

Net Income Per Share	9 Months Ended
	Sep. 30, 2019
Earnings Per Share [Abstract]
Net Income Per Share	NET INCOME PER SHARE Basic and diluted net income per share are presented in the following table. Three Months Ended September 30, Nine Months Ended September 30, (in millions, except per share data) 2019 2018 2019 2018 Basic and diluted Net income $ 292 $ 318 $ 929 $ 925 Less: Income allocated to participating securities 2 2 5 6 Net income attributable to shares $ 290 $ 316 $ 924 $ 919 Basic average shares 147 167 152 170 Basic net income per share $ 1.98 $ 1.89 $ 6.08 $ 5.41 Basic average shares 147 167 152 170 Dilutive stock equivalents: Net effect of the assumed exercise of stock options 1 2 2 2 Net effect of the assumed exercise of warrants — 1 — 1 Diluted average shares 148 170 154 173 Diluted net income per share $ 1.96 $ 1.86 $ 6.02 $ 5.32 The following average shares related to outstanding options to purchase shares of stock were not included in the computation of diluted net income per share because the options were anti-dilutive for the period. Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Average outstanding options 814,044 — 570,433 — Range of exercise prices $67.53 - $95.25 — $67.53 - $95.25 —

Employee Benefit Plans

Employee Benefit Plans	9 Months Ended
	Sep. 30, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]
Employee Benefit Plans	EMPLOYEE BENEFIT PLANS Net periodic defined benefit cost (credit) is comprised of service cost and other components of net benefit cost (credit). Service costs are included in salaries and benefits expense and other components of net benefit cost (credit) are included in other noninterest expenses on the Consolidated Statements of Comprehensive Income. For further information on the Corporation's employee benefit plans, refer to Note 17 to the consolidated financial statements in the Corporation's 2018 Annual Report. The components of net periodic benefit cost (credit) for the Corporation's qualified pension plan, non-qualified pension plan and postretirement benefit plan are as follows. Qualified Defined Benefit Pension Plan Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2019 2018 2019 2018 Service cost $ 8 $ 7 $ 23 $ 22 Other components of net benefit credit: Interest cost 20 19 60 56 Expected return on plan assets (41 ) (41 ) (124 ) (123 ) Amortization of prior service credit (5 ) (5 ) (14 ) (14 ) Amortization of net loss 8 13 25 38 Total other components of net benefit credit (18 ) (14 ) (53 ) (43 ) Net periodic defined benefit credit $ (10 ) $ (7 ) $ (30 ) $ (21 ) Non-Qualified Defined Benefit Pension Plan Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2019 2018 2019 2018 Service cost $ — $ — $ 2 $ 1 Other components of net benefit cost: Interest cost 3 2 7 6 Amortization of prior service credit (2 ) (1 ) (6 ) (6 ) Amortization of net loss 1 2 5 7 Total other components of net benefit cost 2 3 6 7 Net periodic defined benefit cost $ 2 $ 3 $ 8 $ 8 Postretirement Benefit Plan Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2019 2018 2019 2018 Other components of net benefit credit: Interest cost $ — $ — $ 1 $ 1 Expected return on plan assets (1 ) — (2 ) (2 ) Net periodic defined benefit credit $ (1 ) $ — $ (1 ) $ (1 )

Income Taxes And Tax-Related It

Income Taxes And Tax-Related Items	9 Months Ended
	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes and Tax-Related Items	INCOME TAXES AND TAX-RELATED ITEMS At September 30, 2019 , net unrecognized tax benefits were $16 million , compared to $14 million at December 31, 2018 . The Corporation anticipates it is reasonably possible settlements with tax authorities will result in a $1 million decrease in net unrecognized tax benefits within the next twelve months. The liability for tax-related interest and penalties included in accrued expenses and other liabilities was $8 million and $7 million on September 30, 2019 and December 31, 2018 , respectively. Net deferred tax assets were $92 million at September 30, 2019 , compared to $166 million at December 31, 2018 . The $74 million decrease in net deferred tax assets resulted primarily from a decrease in deferred tax assets, due to a decrease in unrealized losses on investment securities, and an increase in deferred tax liabilities arising from cash flow hedges used to manage interest rate risk. Included in deferred tax assets at both September 30, 2019 and December 31, 2018 were $4 million of state net operating loss carryforwards, which expire between 2019 and 2028 . The Corporation believes it is more likely than not that the benefit from certain of these state net operating loss carryforwards will not be realized and, accordingly, maintained a valuation allowance of $3 million at both September 30, 2019 and December 31, 2018 . In the ordinary course of business, the Corporation enters into certain transactions that have tax consequences. From time to time, the Internal Revenue Service (IRS) or other tax jurisdictions may review and/or challenge specific interpretive tax positions taken by the Corporation with respect to those transactions. The Corporation believes its tax returns were filed based upon applicable statutes, regulations and case law in effect at the time of the transactions. The IRS or other tax jurisdictions, an administrative authority or a court, if presented with the transactions, could disagree with the Corporation’s interpretation of the tax law. Based on current knowledge and probability assessment of various potential outcomes, the Corporation believes current tax reserves are adequate, and the amount of any potential incremental liability arising is not expected to have a material adverse effect on the Corporation’s consolidated financial condition or results of operations. Probabilities and outcomes are reviewed as events unfold, and adjustments to the reserves are made when necessary.

Contingent Liabilities

Contingent Liabilities	9 Months Ended
	Sep. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Contingent Liabilities	CONTINGENT LIABILITIES Legal Proceedings As previously reported in the Corporation's Form 10-K for the year ended December 31, 2018 and Forms 10-Q for the periods ended March 31, 2019 and June 30, 2019 , the Bank was named in November 2011 as a third-party defendant in Butte Local Development v. Masters Group v. Comerica Bank (the case), for lender liability. The case was tried in January 2014, in the Montana Second District Judicial Court for Silver Bow County in Butte, Montana. On January 17, 2014 , a jury awarded Masters $52 million against the Bank. On July 1, 2015, after an appeal filed by the Corporation, the Montana Supreme Court reversed the judgment against the Corporation and remanded the case for a new trial with instructions that Michigan contract law should apply and dismissing all other claims. The case was retried in the same district court, without a jury, in January 2017, and the Corporation awaits a ruling. Management believes current reserves related to this case are adequate in the event of a negative outcome. The Corporation and certain of its subsidiaries are subject to various other pending or threatened legal proceedings arising out of the normal course of business or operations. The Corporation believes it has meritorious defenses to the claims asserted against it in its other currently outstanding legal proceedings and, with respect to such legal proceedings, intends to continue to defend itself vigorously, litigating or settling cases according to management’s judgment as to what is in the best interests of the Corporation and its shareholders. Settlement may result from the Corporation's determination that it may be more prudent financially to settle, rather than litigate, and should not be regarded as an admission of liability. On at least a quarterly basis, the Corporation assesses its potential liabilities and contingencies in connection with outstanding legal proceedings utilizing the latest information available. On a case-by-case basis, reserves are established for those legal claims for which it is probable that a loss will be incurred either as a result of a settlement or judgment, and the amount of such loss can be reasonably estimated. The actual costs of resolving these claims may be substantially higher or lower than the amounts reserved. Based on current knowledge, and after consultation with legal counsel, management believes current reserves are adequate, and the amount of any incremental liability arising from these matters is not expected to have a material adverse effect on the Corporation’s consolidated financial condition, results of operations or cash flows. Legal fees of $5 million and $4 million were included in other noninterest expenses for the three-month periods ended September 30, 2019 and 2018 , respectively, and $10 million and $11 million for the nine-month periods ended September 30, 2019 and 2018 , respectively. For matters where a loss is not probable, the Corporation has not established legal reserves. The Corporation believes the estimate of the aggregate range of reasonably possible losses, in excess of reserves established, for all legal proceedings in which it is involved is from zero to approximately $35 million at September 30, 2019 . This estimated aggregate range of reasonably possible losses is based upon currently available information for those proceedings in which the Corporation is involved, taking into account the Corporation’s best estimate of such losses for those cases for which such estimate can be made. For certain cases, the Corporation does not believe an estimate can currently be made. The Corporation’s estimate involves significant judgment, given the varying stages of the proceedings (including the fact many are currently in preliminary stages), the existence in certain proceedings of multiple defendants (including the Corporation) whose share of liability has yet to be determined, the numerous yet-unresolved issues in many of the proceedings (including issues regarding class certification and the scope of many of the claims) and the attendant uncertainty of the various potential outcomes of such proceedings. Accordingly, the Corporation’s estimate will change from time to time, and actual losses may be more or less than the current estimate. In the event of unexpected future developments, it is possible the ultimate resolution of these matters, if unfavorable, may be material to the Corporation's consolidated financial condition, results of operations or cash flows. For information regarding income tax contingencies, refer to Note 11 .

Business Segment Information

Business Segment Information	9 Months Ended
	Sep. 30, 2019
Segment Reporting [Abstract]
Business Segment Information	BUSINESS SEGMENT INFORMATION The Corporation has strategically aligned its operations into three major business segments: the Business Bank, the Retail Bank and Wealth Management. These business segments are differentiated based on the type of customer and the related products and services provided. In addition to the three major business segments, the Finance Division is also reported as a segment. Business segment results are produced by the Corporation’s internal management accounting system. This system measures financial results based on the internal business unit structure of the Corporation. The performance of the business segments is not comparable with the Corporation's consolidated results and is not necessarily comparable with similar information for any other financial institution. Additionally, because of the interrelationships of the various segments, the information presented is not indicative of how the segments would perform if they operated as independent entities. The management accounting system assigns balance sheet and income statement items to each business segment using certain methodologies, which are regularly reviewed and refined. From time to time, the Corporation may make reclassifications among the segments to more appropriately reflect management's current view of the segments, and methodologies may be modified as the management accounting system is enhanced and changes occur in the organizational structure and/or product lines. For comparability purposes, amounts in all periods are based on business unit structure and methodologies in effect at September 30, 2019 . The following discussion provides information about the activities of each business segment. A discussion of the financial results and the factors impacting performance can be found in the section entitled "Business Segments" in the financial review. The Business Bank meets the needs of small and middle market businesses, multinational corporations and governmental entities by offering various products and services including commercial loans and lines of credit, deposits, cash management, capital market products, international trade finance, letters of credit, foreign exchange management services and loan syndication services. The Retail Bank includes a full range of personal financial services, consisting of consumer lending, consumer deposit gathering and mortgage loan origination. This business segment offers a variety of consumer products including deposit accounts, installment loans, credit cards, student loans, home equity lines of credit and residential mortgage loans. Wealth Management offers products and services consisting of fiduciary services, private banking, retirement services, investment management and advisory services, investment banking and brokerage services. This business segment also offers the sale of annuity products, as well as life, disability and long-term care insurance products. The Finance segment includes the Corporation’s securities portfolio and asset and liability management activities. This segment is responsible for managing the Corporation’s funding, liquidity and capital needs, performing interest sensitivity analysis and executing various strategies to manage the Corporation’s exposure to liquidity, interest rate risk and foreign exchange risk. The Other category includes the income and expense impact of equity and cash, tax benefits not assigned to specific business segments, charges of an unusual or infrequent nature that are not reflective of the normal operations of the business segments and miscellaneous other expenses of a corporate nature. For further information on the methodologies which form the basis for these results refer to Note 23 to the consolidated financial statements in the Corporation's 2018 Annual Report. Business segment financial results are as follows: Business Retail Wealth Management Finance Other Total (dollar amounts in millions) Three Months Ended September 30, 2019 Earnings summary: Net interest income (expense) $ 420 $ 142 $ 47 $ (38 ) $ 15 $ 586 Provision for credit losses 39 (2 ) (3 ) — 1 35 Noninterest income 140 31 69 12 4 256 Noninterest expenses 199 149 69 (1 ) 19 435 Provision (benefit) for income taxes 74 5 12 (8 ) (3 ) (a) 80 Net income (loss) $ 248 $ 21 $ 38 $ (17 ) $ 2 $ 292 Net credit-related charge-offs (recoveries) $ 43 $ 1 $ (2 ) $ — $ — $ 42 Selected average balances: Assets $ 45,459 $ 2,871 $ 5,032 $ 14,392 $ 3,982 $ 71,736 Loans 43,889 2,114 4,884 — — 50,887 Deposits 28,917 20,761 3,775 2,049 214 55,716 Statistical data: Return on average assets (b) 2.17 % 0.39 % 3.01 % n/m n/m 1.61 % Efficiency ratio (c) 35.62 84.54 59.79 n/m n/m 51.54 Three Months Ended September 30, 2018 Earnings summary: Net interest income (expense) $ 414 $ 140 $ 46 $ (16 ) $ 15 $ 599 Provision for credit losses — 1 1 — (2 ) — Noninterest income 137 35 66 (7 ) 3 234 Noninterest expenses 211 153 72 (1 ) 17 452 Provision (benefit) for income taxes 76 5 10 (8 ) (20 ) (a) 63 Net income (loss) $ 264 $ 16 $ 29 $ (14 ) $ 23 $ 318 Net credit-related charge-offs $ 14 $ — $ 1 $ — $ — $ 15 Selected average balances: Assets $ 43,165 $ 2,621 $ 5,068 $ 13,696 $ 6,660 $ 71,210 Loans 41,591 2,057 4,936 — — 48,584 Deposits 30,286 20,765 3,988 929 125 56,093 Statistical data: Return on average assets (b) 2.43 % 0.31 % 2.28 % n/m n/m 1.77 % Efficiency ratio (c) 38.24 86.96 63.93 n/m n/m 52.93 (a) Included discrete tax benefits of $5 million and $23 million for the three months ended September 30, 2019 and 2018 , respectively. (b) Return on average assets is calculated based on the greater of average assets or average liabilities and attributed equity. (c) Noninterest expenses as a percentage of the sum of net interest income and noninterest income excluding net gains (losses) from securities and a derivative contract tied to the conversion rate of Visa Class B shares. n/m – not meaningful (dollar amounts in millions) Business Retail Wealth Management Finance Other Total Nine Months Ended September 30, 2019 Earnings summary: Net interest income (expense) $ 1,252 $ 434 $ 140 $ (77 ) $ 46 $ 1,795 Provision for credit losses 85 (5 ) (13 ) — (1 ) 66 Noninterest income 412 95 201 30 6 744 Noninterest expenses 592 441 208 (1 ) 52 1,292 Provision (benefit) for income taxes 227 21 35 (16 ) (15 ) (a) 252 Net income (loss) $ 760 $ 72 $ 111 $ (30 ) $ 16 $ 929 Net credit-related charge-offs (recoveries) $ 90 $ 1 $ (5 ) $ — $ — $ 86 Selected average balances: Assets $ 44,902 $ 2,841 $ 5,092 $ 14,184 $ 3,908 $ 70,927 Loans 43,456 2,108 4,950 — — 50,514 Deposits 28,545 20,628 3,772 1,788 176 54,909 Statistical data: Return on average assets (b) 2.26 % 0.46 % 2.92 % n/m n/m 1.75 % Efficiency ratio (c) 35.61 82.70 61.04 n/m n/m 50.66 Nine Months Ended September 30, 2018 Earnings summary: Net interest income (expense) $ 1,200 $ 402 $ 133 $ (37 ) $ 40 $ 1,738 Provision for credit losses (9 ) (2 ) (2 ) — (4 ) (17 ) Noninterest income 403 100 201 16 6 726 Noninterest expenses 635 450 218 (3 ) 46 1,346 Provision (benefit) for income taxes 222 12 29 (13 ) (40 ) (a) 210 Net income (loss) $ 755 $ 42 $ 89 $ (5 ) $ 44 $ 925 Net credit-related charge-offs $ 40 $ — $ — $ — $ — $ 40 Selected average balances: Assets $ 43,205 $ 2,629 $ 5,233 $ 13,736 $ 5,886 $ 70,689 Loans 41,580 2,062 5,102 — — 48,744 Deposits 30,168 20,888 3,879 949 120 56,004 Statistical data: Return on average assets (b) 2.34 % 0.26 % 2.26 % n/m n/m 1.75 % Efficiency ratio (c) 39.59 89.03 65.51 n/m n/m 54.12 (a) Included discrete tax benefits of $16 million and $48 million for the nine months ended September 30, 2019 and 2018 , respectively. (b) Return on average assets is calculated based on the greater of average assets or average liabilities and attributed equity. (c) Noninterest expenses as a percentage of the sum of net interest income and noninterest income excluding gains (losses) from securities and a derivative contract tied to the conversion rate of Visa Class B shares. n/m – not meaningful The Corporation operates in three primary markets - Texas, California, and Michigan as well as in Arizona and Florida, with select businesses operating in several other states and in Canada and Mexico. The Corporation produces market segment results for the Corporation’s three primary geographic markets as well as Other Markets. Other Markets includes Florida, Arizona, the International Finance division and businesses with a national perspective. The Finance & Other category includes the Finance segment and the Other category as previously described. Market segment results are provided as supplemental information to the business segment results and may not meet all operating segment criteria as set forth in GAAP. For comparability purposes, amounts in all periods are based on market segments and methodologies in effect at September 30, 2019 . A discussion of the financial results and the factors impacting performance can be found in the section entitled "Market Segments" in the financial review. Market segment financial results are as follows: Michigan California Texas Other Finance Total (dollar amounts in millions) Three Months Ended September 30, 2019 Earnings summary: Net interest income (expense) $ 185 $ 203 $ 125 $ 96 $ (23 ) $ 586 Provision for credit losses (1 ) (6 ) 50 (9 ) 1 35 Noninterest income 74 41 31 94 16 256 Noninterest expenses 139 102 86 90 18 435 Provision (benefit) for income taxes 27 37 5 22 (11 ) (a) 80 Net income (loss) $ 94 $ 111 $ 15 $ 87 $ (15 ) $ 292 Net credit-related charge-offs (recoveries) $ 6 $ 5 $ 34 $ (3 ) $ — $ 42 Selected average balances: Assets $ 13,213 $ 18,726 $ 11,462 $ 9,961 $ 18,374 $ 71,736 Loans 12,554 18,393 10,805 9,135 — 50,887 Deposits 20,164 16,725 8,705 7,859 2,263 55,716 Statistical data: Return on average assets (b) 1.78 % 2.37 % 0.48 % 3.47 % n/m 1.61 % Efficiency ratio (c) 53.31 41.64 55.57 47.19 n/m 51.54 Three Months Ended September 30, 2018 Earnings summary: Net interest income (expense) $ 185 $ 200 $ 120 $ 95 $ (1 ) $ 599 Provision for credit losses 4 3 (9 ) 4 (2 ) — Noninterest income 76 43 33 86 (4 ) 234 Noninterest expenses 144 106 89 97 16 452 Provision (benefit) for income taxes 25 34 16 16 (28 ) (a) 63 Net income $ 88 $ 100 $ 57 $ 64 $ 9 $ 318 Net credit-related charge-offs (recoveries) $ 8 $ 5 $ 3 $ (1 ) $ — $ 15 Selected average balances: Assets $ 13,055 $ 18,349 $ 10,263 $ 9,187 $ 20,356 $ 71,210 Loans 12,424 18,074 9,694 8,392 — 48,584 Deposits 20,720 16,894 8,902 8,523 1,054 56,093 Statistical data: Return on average assets (b) 1.63 % 2.18 % 2.18 % 2.74 % n/m 1.77 % Efficiency ratio (c) 54.96 43.10 58.06 54.02 n/m 52.93 (a) Included discrete tax benefits of $5 million and $23 million for the three months ended September 30, 2019 and 2018 , respectively. (b) Return on average assets is calculated based on the greater of average assets or average liabilities and attributed equity. (c) Noninterest expenses as a percentage of the sum of net interest income and noninterest income excluding net gains (losses) from securities and a derivative contract tied to the conversion rate of Visa Class B shares. n/m – not meaningful (dollar amounts in millions) Michigan California Texas Other Finance Total Nine Months Ended September 30, 2019 Earnings summary: Net interest income (expense) $ 557 $ 616 $ 372 $ 281 $ (31 ) $ 1,795 Provision for credit losses (6 ) (11 ) 88 (4 ) (1 ) 66 Noninterest income 218 121 97 272 36 744 Noninterest expenses 412 301 255 273 51 1,292 Provision (benefit) for income taxes 83 113 30 57 (31 ) (a) 252 Net income (loss) $ 286 $ 334 $ 96 $ 227 $ (14 ) $ 929 Net credit-related charge-offs (recoveries) $ 10 $ 9 $ 73 $ (6 ) $ — $ 86 Selected average balances: Assets $ 13,176 $ 19,000 $ 11,240 $ 9,419 $ 18,092 $ 70,927 Loans 12,605 18,695 10,586 8,628 — 50,514 Deposits 19,959 16,433 8,690 7,863 1,964 54,909 Statistical data: Return on average assets (b) 1.85 % 2.36 % 1.13 % 3.23 % n/m 1.75 % Efficiency ratio (c) 53.00 40.82 54.35 49.33 n/m 50.66 Nine Months Ended September 30, 2018 Earnings summary: Net interest income $ 540 $ 582 $ 353 $ 260 $ 3 $ 1,738 Provision for credit losses 38 (8 ) (37 ) (6 ) (4 ) (17 ) Noninterest income 222 124 94 264 22 726 Noninterest expenses 432 316 273 282 43 1,346 Provision (benefit) for income taxes 67 101 48 47 (53 ) (a) 210 Net income $ 225 $ 297 $ 163 $ 201 $ 39 $ 925 Net credit-related charge-offs $ 7 $ 18 $ 11 $ 4 $ — $ 40 Selected average balances: Assets $ 13,291 $ 18,542 $ 10,352 $ 8,882 $ 19,622 $ 70,689 Loans 12,556 18,284 9,789 8,115 — 48,744 Deposits 20,947 16,875 9,016 8,097 1,069 56,004 Statistical data: Return on average assets (b) 1.39 % 2.14 % 2.10 % 3.03 % n/m 1.75 % Efficiency ratio (c) 56.50 44.76 60.92 53.91 n/m 54.12 (a) Included discrete tax benefits of $16 million and $48 million for the nine months ended September 30, 2019 and 2018 , respectively. (b) Return on average assets is calculated based on the greater of average assets or average liabilities and attributed equity. (c) Noninterest expenses as a percentage of the sum of net interest income and noninterest income excluding gains (losses) from securities and a derivative contract tied to the conversion rate of Visa Class B shares. n/m – not meaningful

Revenue from Contracts with Cus

Revenue from Contracts with Customers	9 Months Ended
	Sep. 30, 2019
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers	REVENUE FROM CONTRACTS WITH CUSTOMERS Revenue from contracts with customers comprises the noninterest income earned by the Corporation in exchange for services provided to customers. The following table presents the composition of revenue from contracts with customers, segregated from other sources of noninterest income, by business segment. Business Bank Retail Bank Wealth Management Finance & Other Total (in millions) Three Months Ended September 30, 2019 Revenue from contracts with customers: Card fees $ 55 $ 11 $ 1 $ — $ 67 Service charges on deposit accounts 32 18 1 — 51 Fiduciary income — — 53 — 53 Commercial loan servicing fees (a) 5 — — — 5 Brokerage fees — — 7 — 7 Other noninterest income (b) 1 1 5 — 7 Total revenue from contracts with customers 93 30 67 — 190 Other sources of noninterest income 47 1 2 16 66 Total noninterest income $ 140 $ 31 $ 69 $ 16 $ 256 Three Months Ended September 30, 2018 Revenue from contracts with customers: Card fees $ 50 $ 10 $ 1 $ — $ 61 Service charges on deposit accounts 34 18 1 — 53 Fiduciary income — — 51 — 51 Commercial loan servicing fees (a) 5 — — — 5 Brokerage fees — — 7 — 7 Other noninterest income (b) 3 6 4 — 13 Total revenue from contracts with customers 92 34 64 — 190 Other sources of noninterest income 45 1 2 (4 ) 44 Total noninterest income $ 137 $ 35 $ 66 $ (4 ) $ 234 Nine Months Ended September 30, 2019 Revenue from contracts with customers: Card fees $ 162 $ 30 $ 3 $ — $ 195 Service charges on deposit accounts 98 52 3 — 153 Fiduciary income — — 154 — 154 Commercial loan servicing fees (a) 13 — — — 13 Brokerage fees — — 21 — 21 Other noninterest income (b) 5 8 14 — 27 Total revenue from contracts with customers 278 90 195 — 563 Other sources of noninterest income 134 5 6 36 181 Total noninterest income $ 412 $ 95 $ 201 $ 36 $ 744 Nine Months Ended September 30, 2018 Revenue from contracts with customers: Card fees $ 149 $ 28 $ 3 $ — $ 180 Service charges on deposit accounts 102 54 4 — 160 Fiduciary income — — 155 — 155 Commercial loan servicing fees (a) 14 — — — 14 Brokerage fees — — 20 — 20 Other noninterest income (b) 9 13 12 — 34 Total revenue from contracts with customers 274 95 194 — 563 Other sources of noninterest income 129 5 7 22 163 Total noninterest income $ 403 $ 100 $ 201 $ 22 $ 726 (a) Included in commercial lending fees on the Consolidated Statements of Comprehensive Income. (b) Excludes derivative, warrant and other miscellaneous income. Adjustments to revenue during the three- and nine-month periods ended September 30, 2019 and 2018 for refunds or credits relating to prior periods were not significant. Revenue from contracts with customers did not generate significant contract assets and liabilities.

Leases

Leases	9 Months Ended
	Sep. 30, 2019
Leases (Narrative) [Abstract]
Leases [Abstract]	LEASES As a lessee, the Corporation has entered into operating leases for the majority of its real estate locations, primarily retail and office space. Total lease expenses were $20 million , including $16 million of operating lease expense and $4 million of variable lease expense, for the three months ended September 30, 2019 and $58 million , including $47 million of operating lease expense and $11 million of variable lease expense, for the nine months ended September 30, 2019 . At September 30, 2019 , the Corporation's ROU assets and operating lease liabilities were $320 million and $358 million , respectively. The weighted average lease term for the lease liabilities was 9 years, and the weighted average discount rate of remaining payments was 3.82 percent . Lease liabilities from new ROU assets obtained during the nine months ended September 30, 2019 totaled $35 million . Cash paid on operating lease liabilities was $17 million and $50 million for the three and nine months ended September 30, 2019 , respectively. As of September 30, 2019 , the contractual maturities of operating lease liabilities were as follows: (in millions) Years Ending December 31 2019 (a) $ 10 2020 64 2021 59 2022 50 2023 44 Thereafter 204 Total contractual maturities 431 Less imputed interest (73 ) Total operating lease liabilities $ 358 (a) Contractual maturities for the three months remaining in 2019 . As a lessor, the Corporation leases certain types of manufacturing and warehouse equipment as well as public and private transportation vehicles to its customers. The Corporation recognized lease-related revenue, primarily interest income from sales-type and direct financing leases of $4 million and $10 million for the three and nine months ended September 30, 2019 , respectively. At September 30, 2019 , the Corporation's net investment in sales-type and direct financing leases was $361 million . As of September 30, 2019 , the contractual maturities of sales-type and direct financing lease receivables were as follows: (in millions) Years Ending December 31 2019 (a) $ 18 2020 63 2021 52 2022 88 2023 39 Thereafter 58 Total lease payments receivable 318 Unguaranteed residual values 64 Less deferred interest income (21 ) Total lease receivables (b) $ 361 (a) Contractual maturities for the three months remaining in 2019 . (b) Excludes net investment in leveraged leases of $217 million .

Basis of Presentation and Acc_2

Basis of Presentation and Accounting Policies Basis of Presentation and Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2019
Accounting Policies [Abstract]
Leases	Leases Effective January 1, 2019, the Corporation adopted the provisions of Accounting Standards Update (ASU) No. 2016-02, “Leases (Topic 842),” (ASU 2016-02), for all open leases with a term greater than one year as of the adoption date, using the modified retrospective approach. Prior comparable periods are presented in accordance with previous guidance under Accounting Standards Codification (ASC) 840, “Leases.” Topic 842 requires the recognition of a lease liability, measured as the present value of unpaid lease payments for operating leases where the Corporation is the lessee, and a corresponding right-of-use (ROU) asset for the right to use the leased properties. The Corporation elected not to reassess whether contracts are or contain leases, lease classification or initial direct costs for existing leases, a set of practical expedients for transition provided by ASU 2016-12. Further, the Corporation elected the practical expedient to use hindsight in determining the lease term and assessing impairment. The election of the hindsight practical expedient resulted in longer lease terms for a limited number of strategic locations based on relevant factors as of the adoption date. The impact at adoption was increases of $329 million and $343 million to total assets and liabilities, respectively, and a $14 million reduction to retained earnings. The increase in total assets was due to the recognition of ROU assets recorded in accrued income and other assets, and the increase in total liabilities was due to corresponding recognition of lease payment liabilities recorded in accrued expenses and other liabilities. Operating lease liabilities reflect the Corporation’s obligation to make future lease payments, primarily for real estate locations. Lease terms typically comprise contractual terms but may include extension options reasonably certain of being exercised at lease inception for certain strategic locations such as regional headquarters. Payments are discounted using the rate the Corporation would pay to borrow amounts equal to the lease payments over the lease term (the Corporation’s incremental borrowing rate). The Corporation does not separate lease and non-lease components for contracts in which it is the lessee. ROU assets are measured based on lease liabilities adjusted for incentives as well as accrued and prepaid rent. Operating lease expense is recognized on a straight-line basis over the lease term, while variable lease payments are recognized as incurred. Common area maintenance and other executory costs are the main components of variable lease payments. Operating and variable lease expenses are recorded in net occupancy expense in the Consolidated Statements of Income. The Corporation is the lessor in sales-type, direct finance and leveraged lease arrangements. Leases are recorded at the principal balance outstanding, net of unearned income and charge-offs. Interest income is recognized using the interest method. The impact of adopting Topic 842 for lessor accounting was not significant.
Pending Accounting Pronouncements	Pending Accounting Pronouncements In June 2016, the FASB issued ASU No. 2016-13, "Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments," (ASU 2016-13), which addresses concerns regarding the perceived delay in recognition of credit losses under the existing incurred loss model. The amendment introduces a new, single model for recognizing credit losses on all financial instruments presented on a cost basis. Under the new model, entities must estimate current expected credit losses by considering all available relevant information, including historical and current conditions, as well as reasonable and supportable forecasts of future events. ASU 2016-13 also requires additional qualitative and quantitative disclosure to allow users to better understand the credit risk within the portfolio and the methodologies for determining the allowance for credit losses. ASU 2016-13 is effective for the Corporation on January 1, 2020 and must generally be applied using the modified retrospective approach with a cumulative effect adjustment to retained earnings. In prior periods, the Corporation developed and completed internal validations of new credit estimation models. The Corporation has implemented new processes and controls for the execution of the new model and is in the process of testing them. The implementation team continues to challenge current model assumptions and outputs, refine the qualitative framework and finalize policies and disclosures. Additionally, parallel runs will continue in fourth quarter 2019 as more end-to-end processes, controls and policies are fina lized. Incorporating reasonable and supportable forecasts of economic conditions into the estimate of expected credit losses will require significant judgment, such as selecting economic variables and forecast scenarios as well as determining the appropriate length of the forecast horizon. Management will select economic variables it believes to be most relevant based on the composition of the loan portfolio and customer base, likely to include forecasted levels of employment, gross domestic product, corporate bond and treasury spreads, industrial production levels, consumer and commercial real estate price indices as well as housing statistics. Different economic forecasts ranging from more benign to more severe will be evaluated each reporting period to forecast losses over the contractual life of the loan portfolio. The Corporation anticipates using a two-year forecast horizon, which encompasses most of the remaining contractual life of its portfolio of commercial loans, reverting to its longer-term historical loss experience to estimate expected losses over any remaining contractual life. The ultimate impact of ASU 2016-13 will depend on the composition of the portfolio as well as economic conditions and forecasts at the time of adoption. Based on current factors, the Corporation estimates overall allowance for credit losses to remain within 5 percent of current levels. The commercial portfolio, comprising the majority of the Corporation’s portfolio, consists of loans and lending arrangements with short contractual maturities that are expected to result in a reduction of up to 5 percent in the allowance for credit losses. The allowance for credit losses is expected to increase between 60 to 80 percent for the consumer portfolio given its longer contractual maturities. ASU 2016-13 also requires expected credit losses on available-for-sale securities (AFS) debt securities be recorded as an allowance for credit losses. For certain types of debt securities, such as U.S. Treasuries and other securities with government guarantees, entities may expect zero credit losses. The Corporation believes the zero-loss expectation currently applies to all of its AFS securities. ASU 2016-13 will be adopted in first quarter 2020.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2019
Fair Value Disclosures [Abstract]
Assets And Liabilities Recorded At Fair Value On A Recurring Basis	The following tables present the recorded amount of assets and liabilities measured at fair value on a recurring basis as of September 30, 2019 and December 31, 2018 . (in millions) Total Level 1 Level 2 Level 3 September 30, 2019 Deferred compensation plan assets $ 92 $ 92 $ — $ — Equity securities 49 49 — — Investment securities available-for-sale: U.S. Treasury and other U.S. government agency securities 2,796 2,796 — — Residential mortgage-backed securities (a) 9,633 — 9,633 — Total investment securities available-for-sale 12,429 2,796 9,633 — Derivative assets: Interest rate contracts 275 — 247 28 Energy derivative contracts 160 — 160 — Foreign exchange contracts 13 — 13 — Total derivative assets 448 — 420 28 Total assets at fair value $ 13,018 $ 2,937 $ 10,053 $ 28 Derivative liabilities: Interest rate contracts $ 43 $ — $ 43 $ — Energy derivative contracts 156 — 156 — Foreign exchange contracts 10 — 10 — Total derivative liabilities 209 — 209 — Deferred compensation plan liabilities 92 92 — — Total liabilities at fair value $ 301 $ 92 $ 209 $ — December 31, 2018 Deferred compensation plan assets $ 88 $ 88 $ — $ — Equity securities 43 43 — — Investment securities available-for-sale: U.S. Treasury and other U.S. government agency securities 2,727 2,727 — — Residential mortgage-backed securities (a) 9,318 — 9,318 — Total investment securities available-for-sale 12,045 2,727 9,318 — Derivative assets: Interest rate contracts 67 — 58 9 Energy derivative contracts 189 — 189 — Foreign exchange contracts 19 — 19 — Total derivative assets 275 — 266 9 Total assets at fair value $ 12,451 $ 2,858 $ 9,584 $ 9 Derivative liabilities: Interest rate contracts $ 70 $ — $ 70 $ — Energy derivative contracts 186 — 186 — Foreign exchange contracts 13 — 13 — Total derivative liabilities 269 — 269 — Deferred compensation plan liabilities 88 88 — — Total liabilities at fair value $ 357 $ 88 $ 269 $ — (a) Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises.
Changes In Level 3 Assets And Liabilities Measured At Fair Value On A Recurring Basis	The following table summarizes the changes in Level 3 assets and liabilities measured at fair value on a recurring basis for the three- and nine-month periods ended September 30, 2019 and 2018 . Net Realized/Unrealized Gains (Losses) (Pretax) Recorded in Earnings (b) Balance at Beginning of Period Change in Classification (a) Balance at End of Period Payments, Sales and Redemptions (in millions) Realized Unrealized Three Months Ended September 30, 2019 Derivative assets: Interest rate contracts $ 21 $ — $ 1 $ 7 $ (1 ) $ 28 Three Months Ended September 30, 2018 Derivative assets: Interest rate contracts $ 6 $ — $ — $ (4 ) $ — $ 2 Nine Months Ended September 30, 2019 Derivative assets: Interest rate contracts $ 9 — 1 19 (1 ) 28 Nine Months Ended September 30, 2018 Equity securities $ — $ 44 $ — $ — $ (44 ) $ — Investment securities available-for-sale: State and municipal securities (c) 5 — — — (5 ) — Equity and other non-debt securities (c) 44 (44 ) — — — — Total investment securities available-for-sale 49 (44 ) — — (5 ) — Derivative assets: Interest rate contracts 14 — — (12 ) — 2 (a) Reflects the reclassification of equity securities resulting from the adoption of ASU 2016-01. (b) Realized and unrealized gains and losses due to changes in fair value are recorded in other noninterest income on the Consolidated Statements of Comprehensive Income. (c) Auction-rate securities.
Assets And Liabilities Recorded At Fair Value On A Nonrecurring Basis	The following table presents assets recorded at fair value on a nonrecurring basis at September 30, 2019 and December 31, 2018 . No liabilities were recorded at fair value on a nonrecurring basis at September 30, 2019 and December 31, 2018 . (in millions) Level 3 September 30, 2019 Loans: Commercial $ 25 Total assets at fair value $ 25 December 31, 2018 Loans: Commercial $ 33 Commercial mortgage 2 Total assets at fair value $ 35
Estimated Fair Values Of Financial Instruments Not Recorded At Fair Value In Their Entirety On A Recurring Basis	The carrying amount and estimated fair value of financial instruments not recorded at fair value in their entirety on a recurring basis on the Corporation’s Consolidated Balance Sheets are as follows: Carrying Amount Estimated Fair Value (in millions) Total Level 1 Level 2 Level 3 September 30, 2019 Assets Cash and due from banks $ 1,229 $ 1,229 $ 1,229 $ — $ — Interest-bearing deposits with banks 2,888 2,888 2,888 — — Loans held-for-sale 4 4 — 4 — Total loans, net of allowance for loan losses (a) 50,839 51,008 — — 51,008 Customers’ liability on acceptances outstanding 2 2 2 — — Restricted equity investments 248 248 248 — — Nonmarketable equity securities (b) 6 10 — — — Liabilities Demand deposits (noninterest-bearing) 27,134 27,134 — 27,134 — Interest-bearing deposits 26,175 26,175 — 26,175 — Customer certificates of deposit 2,853 2,842 — 2,842 — Other time deposits 647 647 — 647 — Total deposits 56,809 56,798 — 56,798 — Short-term borrowings 51 51 51 — — Acceptances outstanding 2 2 2 — — Medium- and long-term debt 7,311 7,316 — 7,316 — Credit-related financial instruments (56 ) (56 ) — — (56 ) December 31, 2018 Assets Cash and due from banks $ 1,390 $ 1,390 $ 1,390 $ — $ — Interest-bearing deposits with banks 3,171 3,171 3,171 — — Loans held-for-sale 3 3 — 3 — Total loans, net of allowance for loan losses (a) 49,492 48,889 — — 48,889 Customers’ liability on acceptances outstanding 4 4 4 — — Restricted equity investments 248 248 248 — — Nonmarketable equity securities (b) 6 11 Liabilities Demand deposits (noninterest-bearing) 28,690 28,690 — 28,690 — Interest-bearing deposits 24,740 24,740 — 24,740 — Certificates of deposit 2,131 2,100 — 2,100 — Total deposits 55,561 55,530 — 55,530 — Short-term borrowings 44 44 44 — — Acceptances outstanding 4 4 4 — — Medium- and long-term debt 6,463 6,436 — 6,436 — Credit-related financial instruments (57 ) (57 ) — — (57 ) (a) Included $25 million and $35 million of impaired loans recorded at fair value on a nonrecurring basis at September 30, 2019 and December 31, 2018 , respectively. (b) Certain investments that are measured at fair value using the net asset value have not been classified in the fair value hierarchy. The fair value amounts presented in the table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the Consolidated Balance Sheets.

Investment Securities (Tables)

Investment Securities (Tables)	9 Months Ended
	Sep. 30, 2019
Investments, Debt and Equity Securities [Abstract]
Summary Of Investment Securities	A summary of the Corporation’s investment securities follows: (in millions) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value September 30, 2019 Investment securities available-for-sale: U.S. Treasury and other U.S. government agency securities $ 2,744 $ 52 $ — $ 2,796 Residential mortgage-backed securities (a) 9,590 74 31 9,633 Total investment securities available-for-sale $ 12,334 $ 126 $ 31 $ 12,429 December 31, 2018 Investment securities available-for-sale: U.S. Treasury and other U.S. government agency securities $ 2,732 $ 14 $ 19 $ 2,727 Residential mortgage-backed securities (a) 9,493 22 197 9,318 Total investment securities available-for-sale $ 12,225 $ 36 $ 216 $ 12,045 (a) Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises.
Summary Of Investment Securities In Unrealized Loss Positions	A summary of the Corporation’s investment securities in an unrealized loss position as of September 30, 2019 and December 31, 2018 follows: Temporarily Impaired Less than 12 Months 12 Months or more Total (in millions) Fair Value Unrealized Losses Fair Value Unrealized Losses Fair Value Unrealized Losses September 30, 2019 Residential mortgage-backed securities (a) $ 1,412 $ 4 $ 2,130 $ 27 $ 3,542 $ 31 Total temporarily impaired securities $ 1,412 $ 4 $ 2,130 $ 27 $ 3,542 $ 31 December 31, 2018 U.S. Treasury and other U.S. government agency securities $ — $ — $ 1,457 $ 19 $ 1,457 $ 19 Residential mortgage-backed securities (a) 1,008 9 6,412 188 7,420 197 Total temporarily impaired securities $ 1,008 $ 9 $ 7,869 $ 207 $ 8,877 $ 216 (a) Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises.
Summary of Net Securities Gains (Losses)	Sales, calls and write-downs of investment securities available-for-sale resulted in the following gains and losses recorded in net securities losses on the Consolidated Statements of Comprehensive Income, computed based on the adjusted cost of the specific security. Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2019 2018 2019 2018 Securities gains $ — $ — $ — $ 1 Securities losses — (20 ) (8 ) (20 ) Net securities $ — $ (20 ) $ (8 ) $ (19 )
Contractual Maturity Distribution Of Debt Securities	The following table summarizes the amortized cost and fair values of debt securities by contractual maturity. Securities with multiple maturity dates are classified in the period of final maturity. Expected maturities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. (in millions) September 30, 2019 Amortized Cost Fair Value Contractual maturity Within one year $ 30 $ 31 After one year through five years 2,818 2,874 After five years through ten years 1,127 1,134 After ten years 8,359 8,390 Total investment securities $ 12,334 $ 12,429

Credit Quality And Allowance _2

Credit Quality And Allowance For Credit Losses (Tables)	9 Months Ended
	Sep. 30, 2019
Credit Quality And Allowance For Credit Losses [Abstract]
Aging Analysis Of Loans	The following table presents an aging analysis of the recorded balance of loans. Loans Past Due and Still Accruing (in millions) 30-59 Days 60-89 Days 90 Days or More Total Nonaccrual Loans Current Loans Total Loans September 30, 2019 Business loans: Commercial $ 44 $ 28 $ 28 $ 100 $ 152 $ 32,638 $ 32,890 Real estate construction: Commercial Real Estate business line (a) 1 — — 1 — 2,989 2,990 Other business lines (b) — — — — — 387 387 Total real estate construction 1 — — 1 — 3,376 3,377 Commercial mortgage: Commercial Real Estate business line (a) 5 — — 5 2 1,941 1,948 Other business lines (b) 37 3 2 42 11 7,233 7,286 Total commercial mortgage 42 3 2 47 13 9,174 9,234 Lease financing — — — — — 578 578 International — — 1 1 2 1,052 1,055 Total business loans 87 31 31 149 167 46,818 47,134 Retail loans: Residential mortgage 10 3 — 13 36 1,857 1,906 Consumer: Home equity 4 1 — 5 17 1,700 1,722 Other consumer 2 — — 2 — 727 729 Total consumer 6 1 — 7 17 2,427 2,451 Total retail loans 16 4 — 20 53 4,284 4,357 Total loans $ 103 $ 35 $ 31 $ 169 $ 220 $ 51,102 $ 51,491 December 31, 2018 Business loans: Commercial $ 34 $ 26 $ 8 $ 68 $ 141 $ 31,767 $ 31,976 Real estate construction: Commercial Real Estate business line (a) 6 — — 6 — 2,681 2,687 Other business lines (b) 6 — — 6 — 384 390 Total real estate construction 12 — — 12 — 3,065 3,077 Commercial mortgage: Commercial Real Estate business line (a) 4 — — 4 2 1,737 1,743 Other business lines (b) 32 5 8 45 18 7,300 7,363 Total commercial mortgage 36 5 8 49 20 9,037 9,106 Lease financing — — — — 2 505 507 International — — — — 3 1,010 1,013 Total business loans 82 31 16 129 166 45,384 45,679 Retail loans: Residential mortgage 11 3 — 14 36 1,920 1,970 Consumer: Home equity 4 1 — 5 19 1,741 1,765 Other consumer 1 — — 1 — 748 749 Total consumer 5 1 — 6 19 2,489 2,514 Total retail loans 16 4 — 20 55 4,409 4,484 Total loans $ 98 $ 35 $ 16 $ 149 $ 221 $ 49,793 $ 50,163 (a) Primarily loans to real estate developers. (b) Primarily loans secured by owner-occupied real estate.
Loans By Credit Quality Indicator	The following table presents loans by credit quality indicator, based on internal risk ratings assigned to each business loan at the time of approval and subjected to subsequent reviews, generally at least annually, and to pools of retail loans with similar risk characteristics. Internally Assigned Rating (in millions) Pass (a) Special Mention (b) Substandard (c) Nonaccrual (d) Total September 30, 2019 Business loans: Commercial $ 31,420 $ 724 $ 594 $ 152 $ 32,890 Real estate construction: Commercial Real Estate business line (e) 2,954 36 — — 2,990 Other business lines (f) 387 — — — 387 Total real estate construction 3,341 36 — — 3,377 Commercial mortgage: Commercial Real Estate business line (e) 1,892 13 41 2 1,948 Other business lines (f) 7,097 99 79 11 7,286 Total commercial mortgage 8,989 112 120 13 9,234 Lease financing 566 10 2 — 578 International 1,025 23 5 2 1,055 Total business loans 45,341 905 721 167 47,134 Retail loans: Residential mortgage 1,868 2 — 36 1,906 Consumer: Home equity 1,698 1 6 17 1,722 Other consumer 723 6 — — 729 Total consumer 2,421 7 6 17 2,451 Total retail loans 4,289 9 6 53 4,357 Total loans $ 49,630 $ 914 $ 727 $ 220 $ 51,491 December 31, 2018 Business loans: Commercial $ 30,817 $ 464 $ 554 $ 141 $ 31,976 Real estate construction: Commercial Real Estate business line (e) 2,664 23 — — 2,687 Other business lines (f) 382 8 — — 390 Total real estate construction 3,046 31 — — 3,077 Commercial mortgage: Commercial Real Estate business line (e) 1,682 14 45 2 1,743 Other business lines (f) 7,157 118 70 18 7,363 Total commercial mortgage 8,839 132 115 20 9,106 Lease financing 500 3 2 2 507 International 996 4 10 3 1,013 Total business loans 44,198 634 681 166 45,679 Retail loans: Residential mortgage 1,931 3 — 36 1,970 Consumer: Home equity 1,738 — 8 19 1,765 Other consumer 748 1 — — 749 Total consumer 2,486 1 8 19 2,514 Total retail loans 4,417 4 8 55 4,484 Total loans $ 48,615 $ 638 $ 689 $ 221 $ 50,163 (a) Includes all loans not included in the categories of special mention, substandard or nonaccrual. (b) Special mention loans are accruing loans that have potential credit weaknesses that deserve management’s close attention, such as loans to borrowers who may be experiencing financial difficulties that may result in deterioration of repayment prospects from the borrower at some future date. This category is generally consistent with the "special mention" category as defined by regulatory authorities. (c) Substandard loans are accruing loans that have a well-defined weakness, or weaknesses, such as loans to borrowers who may be experiencing losses from operations or inadequate liquidity of a degree and duration that jeopardizes the orderly repayment of the loan. Substandard loans also are distinguished by the distinct possibility of loss in the future if these weaknesses are not corrected. This category is generally consistent with the "substandard" category as defined by regulatory authorities. (d) Nonaccrual loans are loans for which the accrual of interest has been discontinued. For further information regarding nonaccrual loans, refer to the Nonperforming Assets subheading in Note 1 - Basis of Presentation and Accounting Policies - on pages F-52 and F-53 in the Corporation's 2018 Annual Report. A significant majority of nonaccrual loans are generally consistent with the "substandard" category and the remainder are generally consistent with the "doubtful" category as defined by regulatory authorities. (e) Primarily loans to real estate developers. (f) Primarily loans secured by owner-occupied real estate.
Schedule Of Nonaccrual, Reduced-Rate Loans And Foreclosed Property	The following table summarizes nonperforming assets. (in millions) September 30, 2019 December 31, 2018 Nonaccrual loans $ 220 $ 221 Reduced-rate loans (a) 6 8 Total nonperforming loans 226 229 Foreclosed property 3 1 Total nonperforming assets $ 229 $ 230 (a)
Changes In The Allowance For Loan Losses And Related Loan Amounts	The following table details the changes in the allowance for loan losses and related loan amounts. 2019 2018 (in millions) Business Loans Retail Loans Total Business Loans Retail Loans Total Three Months Ended September 30 Allowance for loan losses: Balance at beginning of period $ 618 $ 39 $ 657 $ 635 $ 42 $ 677 Loan charge-offs (59 ) (2 ) (61 ) (24 ) (1 ) (25 ) Recoveries on loans previously charged-off 17 2 19 9 1 10 Net loan charge-offs (42 ) — (42 ) (15 ) — (15 ) Provision for loan losses 39 (2 ) 37 (1 ) 2 1 Foreign currency translation adjustment — — — 1 — 1 Balance at end of period $ 615 $ 37 $ 652 $ 620 $ 44 $ 664 Nine Months Ended September 30 Allowance for loan losses: Balance at beginning of period $ 627 $ 44 $ 671 $ 661 $ 51 $ 712 Loan charge-offs (121 ) (4 ) (125 ) (78 ) (4 ) (82 ) Recoveries on loans previously charged-off 35 4 39 39 3 42 Net loan charge-offs (86 ) — (86 ) (39 ) (1 ) (40 ) Provision for loan losses 74 (7 ) 67 (2 ) (6 ) (8 ) Balance at end of period $ 615 $ 37 $ 652 $ 620 $ 44 $ 664 As a percentage of total loans 1.30 % 0.86 % 1.27 % 1.39 % 1.00 % 1.35 % September 30 Allowance for loan losses: Individually evaluated for impairment $ 34 $ — $ 34 $ 29 $ — $ 29 Collectively evaluated for impairment 581 37 618 591 44 635 Total allowance for loan losses $ 615 $ 37 $ 652 $ 620 $ 44 $ 664 Loans: Individually evaluated for impairment $ 209 $ 34 $ 243 $ 269 $ 34 $ 303 Collectively evaluated for impairment 46,925 4,323 51,248 44,358 4,349 48,707 Total loans evaluated for impairment $ 47,134 $ 4,357 $ 51,491 $ 44,627 $ 4,383 $ 49,010
Changes In the Allowance For Credit Losses On Lending-Related Commitments	2019 2018 (in millions) Business Loans Retail Loans Total Business Loans Retail Loans Total Three Months Ended September 30 Allowance for loan losses: Balance at beginning of period $ 618 $ 39 $ 657 $ 635 $ 42 $ 677 Loan charge-offs (59 ) (2 ) (61 ) (24 ) (1 ) (25 ) Recoveries on loans previously charged-off 17 2 19 9 1 10 Net loan charge-offs (42 ) — (42 ) (15 ) — (15 ) Provision for loan losses 39 (2 ) 37 (1 ) 2 1 Foreign currency translation adjustment — — — 1 — 1 Balance at end of period $ 615 $ 37 $ 652 $ 620 $ 44 $ 664 Nine Months Ended September 30 Allowance for loan losses: Balance at beginning of period $ 627 $ 44 $ 671 $ 661 $ 51 $ 712 Loan charge-offs (121 ) (4 ) (125 ) (78 ) (4 ) (82 ) Recoveries on loans previously charged-off 35 4 39 39 3 42 Net loan charge-offs (86 ) — (86 ) (39 ) (1 ) (40 ) Provision for loan losses 74 (7 ) 67 (2 ) (6 ) (8 ) Balance at end of period $ 615 $ 37 $ 652 $ 620 $ 44 $ 664 As a percentage of total loans 1.30 % 0.86 % 1.27 % 1.39 % 1.00 % 1.35 % September 30 Allowance for loan losses: Individually evaluated for impairment $ 34 $ — $ 34 $ 29 $ — $ 29 Collectively evaluated for impairment 581 37 618 591 44 635 Total allowance for loan losses $ 615 $ 37 $ 652 $ 620 $ 44 $ 664 Loans: Individually evaluated for impairment $ 209 $ 34 $ 243 $ 269 $ 34 $ 303 Collectively evaluated for impairment 46,925 4,323 51,248 44,358 4,349 48,707 Total loans evaluated for impairment $ 47,134 $ 4,357 $ 51,491 $ 44,627 $ 4,383 $ 49,010 Changes in the allowance for credit losses on lending-related commitments, included in accrued expenses and other liabilities on the Consolidated Balance Sheets, are summarized in the following table. Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2019 2018 2019 2018 Balance at beginning of period $ 31 $ 34 $ 30 $ 42 Provision for credit losses on lending-related commitments (2 ) (1 ) (1 ) (9 ) Balance at end of period $ 29 $ 33 $ 29 $ 33
Individually Evaluated Impaired Loans	The following table presents additional information regarding individually evaluated impaired loans. Recorded Investment In: (in millions) Impaired Loans with No Related Allowance Impaired Loans with Related Allowance Total Impaired Loans Unpaid Principal Balance Related Allowance for Loan Losses September 30, 2019 Business loans: Commercial $ 12 $ 143 $ 155 $ 253 $ 32 Commercial mortgage: Commercial Real Estate business line (a) 39 — 39 49 — Other business lines (b) 1 11 12 16 2 Total commercial mortgage 40 11 51 65 2 International 2 1 3 9 — Total business loans 54 155 209 327 34 Retail loans: Residential mortgage 17 8 25 27 — Consumer: Home equity 9 — 9 10 — Total retail loans (c) 26 8 34 37 — Total individually evaluated impaired loans $ 80 $ 163 $ 243 $ 364 $ 34 December 31, 2018 Business loans: Commercial $ 50 $ 130 $ 180 $ 227 $ 24 Commercial mortgage: Commercial Real Estate business line (a) 39 — 39 49 — Other business lines (b) 2 16 18 23 3 Total commercial mortgage 41 16 57 72 3 International 2 1 3 8 — Total business loans 93 147 240 307 27 Retail loans: Residential mortgage 16 8 24 25 — Consumer: Home equity 11 — 11 13 — Other consumer 1 — 1 1 — Total consumer 12 — 12 14 — Total retail loans (c) 28 8 36 39 — Total individually evaluated impaired loans $ 121 $ 155 $ 276 $ 346 $ 27 (a) Primarily loans to real estate developers. (b) Primarily loans secured by owner-occupied real estate. (c) Individually evaluated retail loans generally have no related allowance for loan losses, primarily due to policy which results in direct write-downs of most restructured retail loans.
Average Individually Evaluated Impaired Loans And Related Interest Recognized	The following table presents information regarding average individually evaluated impaired loans and the related interest recognized as of September 30, 2019 and 2018 . Interest income recognized for the period primarily related to performing restructured loans. Individually Evaluated Impaired Loans 2019 2018 (in millions) Average Balance for the Period Interest Income Recognized for the Period Average Balance for the Period Interest Income Recognized for the Period Three Months Ended September 30 Business loans: Commercial $ 152 $ — $ 221 $ 2 Commercial mortgage: Commercial Real Estate business line (a) 39 1 40 1 Other business lines (b) 13 1 24 — Total commercial mortgage 52 2 64 1 Lease financing 1 — — — International 3 — 5 — Total business loans 208 2 290 3 Retail loans: Residential mortgage 24 1 20 — Consumer loans: Home equity 9 — 11 — Other consumer — — 1 — Total consumer 9 — 12 — Total retail loans 33 1 32 — Total individually evaluated impaired loans $ 241 $ 3 $ 322 $ 3 Nine Months Ended September 30 Business loans: Commercial $ 157 $ 2 $ 282 $ 4 Commercial mortgage: Commercial Real Estate business line (a) 39 2 40 3 Other business lines (b) 15 1 24 — Total commercial mortgage 54 3 64 3 Lease financing 1 — — — International 3 — 5 — Total business loans 215 5 351 7 Retail loans: Residential mortgage 24 1 20 — Consumer: Home equity 9 — 11 — Other consumer 1 — 1 — Total consumer 10 — 12 — Total retail loans 34 1 32 — Total individually evaluated impaired loans $ 249 $ 6 $ 383 $ 7 (a) Primarily loans to real estate developers. (b) Primarily loans secured by owner-occupied real estate.
Troubled Debt Restructurings By Type Of Modification	The following table details the recorded balance at September 30, 2019 and 2018 of loans considered to be troubled debt restructurings (TDRs) that were restructured during the three- and nine-month periods ended September 30, 2019 and 2018 , by type of modification. In cases of loans with more than one type of modification, the loans were categorized based on the most significant modification. 2019 2018 Type of Modification Type of Modification (in millions) Principal Deferrals (a) Interest Rate Reductions Total Modifications Principal Deferrals (a) Interest Rate Reductions Total Modifications Three Months Ended September 30, Business loans: Commercial $ 11 $ — $ 11 $ 1 $ — $ 1 Commercial mortgage: Other business lines (b) — — — 1 — 1 International — — — 1 — 1 Total business loans 11 — 11 3 — 3 Retail loans: Consumer: Home equity (c) — — — — 2 2 Total loans $ 11 $ — $ 11 $ 3 $ 2 $ 5 Nine Months Ended September 30, Business loans: Commercial $ 19 $ — $ 19 $ 32 $ — $ 32 Commercial mortgage: Other business lines (b) — — — 3 — 3 International — — — 1 — 1 Total business loans 19 — 19 36 — 36 Retail loans: Consumer: Home equity (c) — 1 1 — 3 3 Total loans $ 19 $ 1 $ 20 $ 36 $ 3 $ 39 (a) Primarily represents loan balances where terms were extended 90 days or more at or above contractual interest rates. Also includes commercial loans restructured in bankruptcy. (b) Primarily loans secured by owner-occupied real estate. (c) Includes bankruptcy loans for which the court has discharged the borrower's obligation and the borrower has not reaffirmed the debt.
Troubled Debt Restructuring Subsequent Default	The following table presents information regarding the recorded balance at September 30, 2019 and 2018 of loans modified by principal deferral during the twelve-month periods ended September 30, 2019 and 2018 . Principal Deferrals (in millions) 2019 2018 September 30 Business loans: Commercial $ 19 $ 59 Commercial mortgage: Other business lines (a) — 3 International — 1 Total business loans 19 63 Retail loans: Consumer: Home equity (b) — 1 Total loans $ 19 $ 64 (a) Primarily loans secured by owner-occupied real estate. (b) Includes bankruptcy loans for which the court has discharged the borrower's obligation and the borrower has not reaffirmed the debt.

Derivative And Credit-Related_2

Derivative And Credit-Related Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule Of Derivative Instruments	The following table presents the composition of the Corporation’s derivative instruments held or issued for risk management purposes or in connection with customer-initiated and other activities at September 30, 2019 and December 31, 2018 . The table excludes commitments and warrants accounted for as derivatives. September 30, 2019 December 31, 2018 Fair Value Fair Value (in millions) Notional/ Contract Amount (a) Gross Derivative Assets Gross Derivative Liabilities Notional/ Contract Amount (a) Gross Derivative Assets Gross Derivative Liabilities Risk management purposes Derivatives designated as hedging instruments Interest rate contracts: Swaps - fair value - receive fixed/pay floating $ 3,325 $ — $ — $ 2,625 $ — $ 2 Swaps - cash flow - receive fixed/pay floating 3,800 — — — — — Derivatives used as economic hedges Foreign exchange contracts: Spot, forwards and swaps 309 1 — 302 1 1 Total risk management purposes 7,434 1 — 2,927 1 3 Customer-initiated and other activities Interest rate contracts: Caps and floors written 912 — 1 885 — 1 Caps and floors purchased 912 1 — 885 1 — Swaps 15,687 274 42 13,115 66 67 Total interest rate contracts 17,511 275 43 14,885 67 68 Energy contracts: Caps and floors written 468 — 30 278 — 26 Caps and floors purchased 468 30 — 278 26 — Swaps 2,147 130 126 2,094 163 160 Total energy contracts 3,083 160 156 2,650 189 186 Foreign exchange contracts: Spot, forwards, options and swaps 1,061 12 10 1,095 18 12 Total customer-initiated and other activities 21,655 447 209 18,630 274 266 Total gross derivatives $ 29,089 $ 448 $ 209 $ 21,557 $ 275 $ 269 Amounts offset in the Consolidated Balance Sheets: Netting adjustment - Offsetting derivative assets/liabilities (45 ) (45 ) (45 ) (45 ) Netting adjustment - Cash collateral received/posted (101 ) (12 ) (174 ) (1 ) Net derivatives included in the Consolidated Balance Sheets (b) 302 152 56 223 Amounts not offset in the Consolidated Balance Sheets: Marketable securities pledged under bilateral collateral agreements (1 ) (26 ) (1 ) — Net derivatives after deducting amounts not offset in the Consolidated Balance Sheets $ 301 $ 126 $ 55 $ 223 (a) Notional or contractual amounts, which represent the extent of involvement in the derivatives market, are used to determine the contractual cash flows required in accordance with the terms of the agreement. These amounts are typically not exchanged, significantly exceed amounts subject to credit or market risk and are not reflected in the Consolidated Balance Sheets. (b) Net derivative assets are included in accrued income and other assets and net derivative liabilities are included in accrued expenses and other liabilities on the Consolidated Balance Sheets. Included in the fair value of net derivative assets and net derivative liabilities are credit valuation adjustments reflecting counterparty credit risk and credit risk of the Corporation. The fair value of net derivative assets included credit valuation adjustments for counterparty credit risk of $12 million and $2 million at September 30, 2019 and December 31, 2018 , respectively.
Schedule of the Effects of Fair Value Hedging on the Consolidated Statements of Comprehensive Income	The following table details the effects of fair value hedging on the Consolidated Statements of Comprehensive Income. Interest on Medium- and Long-Term Debt Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2019 2018 2019 2018 Total interest on medium-and long-term debt (a) $ 50 $ 40 $ 152 $ 97 Fair value hedging relationships: Interest rate contracts: Hedged items 28 21 80 51 Derivatives designated as hedging instruments (2 ) (1 ) (1 ) (7 ) (a) Includes the effects of hedging.
Schedule Of Weighted Average Maturity And Interest Rates On Risk Management Interest Rate Swaps	The following table summarizes the expected weighted average remaining maturity of the notional amount of risk management interest rate swaps, the carrying amount of the related hedged items and the weighted average interest rates associated with amounts expected to be received or paid on interest rate swap agreements as of September 30, 2019 and December 31, 2018 . Weighted Average (dollar amounts in millions) Derivative Notional Amount Carrying Value of Hedged Items (a) Remaining Maturity (in years) Receive Rate Pay Rate (b) September 30, 2019 Swaps - cash flow - receive fixed/pay floating rate Variable rate loans $ 3,800 3.3 2.04 2.07 Swaps - fair value - receive fixed/pay floating rate Medium- and long-term debt 3,325 $ 3,511 4.8 3.44 3.09 December 31, 2018 Swaps - fair value - receive fixed/pay floating rate Medium- and long-term debt 2,625 2,663 3.9 3.40 3.45 (a) Included $ 189 million and $ 49 million of cumulative hedging adjustments to fair value hedges at September 30, 2019 and December 31, 2018 , respectively, which included $ 7 million and $ 8 million , respectively, of hedging adjustment on a discontinued hedging relationship. (b) Variable rates paid on receive fixed swaps designated as fair value and cash flow hedges are based on one- and six-month LIBOR rates in effect at September 30, 2019 and December 31, 2018
Schedule Of Net Gains Recognized In Income On Customer-Initiated Derivatives	The net gains recognized in income on customer-initiated derivative instruments, net of the impact of offsetting positions, were as follows . Three Months Ended September 30, Nine Months Ended September 30, (in millions) Location of Gain 2019 2018 2019 2018 Interest rate contracts Other noninterest income $ 4 $ 9 $ 16 $ 20 Energy contracts Other noninterest income 1 1 4 1 Foreign exchange contracts Foreign exchange income 11 11 33 35 Total $ 16 $ 21 $ 53 $ 56
Schedule Of Financial Instruments With Off-Balance Sheet Credit Risk	The Corporation’s credit risk associated with these instruments is represented by the contractual amounts indicated in the following table. (in millions) September 30, 2019 December 31, 2018 Unused commitments to extend credit: Commercial and other $ 23,280 $ 24,266 Bankcard, revolving check credit and home equity loan commitments 3,156 3,001 Total unused commitments to extend credit $ 26,436 $ 27,267 Standby letters of credit $ 3,281 $ 3,244 Commercial letters of credit 17 39
Summary Of Criticized Letters Of Credit	The following table presents a summary of criticized standby and commercial letters of credit at September 30, 2019 and December 31, 2018 . The Corporation's criticized list is generally consistent with the Special Mention, Substandard and Doubtful categories defined by regulatory authorities. The Corporation manages credit risk through underwriting, periodically reviewing and approving its credit exposures using Board committee approved credit policies and guidelines. (dollar amounts in millions) September 30, 2019 December 31, 2018 Total criticized standby and commercial letters of credit $ 45 $ 49 As a percentage of total outstanding standby and commercial letters of credit 1.4 % 1.5 %

Variable Interest Entities (V_2

Variable Interest Entities (VIEs) (Tables)	9 Months Ended
	Sep. 30, 2019
Variable Interest Entity, Not Primary Beneficiary, Disclosures [Abstract]
Impact Of VIEs On The Consolidated Statements Of Comprehensive Income	The following table summarizes the impact of these tax credit entities on line items on the Corporation’s Consolidated Statements of Comprehensive Income. Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2019 2018 2019 2018 Other noninterest income: Amortization of other tax credit investments $ — $ — $ 1 $ 2 Provision for income taxes: Amortization of LIHTC investments 16 17 48 48 Low income housing tax credits (16 ) (16 ) (46 ) (46 ) Other tax benefits related to tax credit entities (3 ) (4 ) (10 ) (11 ) Total provision for income taxes $ (3 ) $ (3 ) $ (8 ) $ (9 )

Medium- And Long-Term Debt (Tab

Medium- And Long-Term Debt (Tables)	9 Months Ended
	Sep. 30, 2019
Debt Disclosure [Abstract]
Schedule Of Medium- And Long-Term Debt	Medium- and long-term debt is summarized as follows: (in millions) September 30, 2019 December 31, 2018 Parent company Subordinated notes: 3.80% subordinated notes due 2026 (a) $ 269 $ 250 Medium- and long-term notes: 2.125% notes due 2019 (a) — 348 3.70% notes due 2023 (a) 892 861 4.00% notes due 2029 (a) 603 — Total medium- and long-term notes 1,495 1,209 Total parent company 1,764 1,459 Subsidiaries Subordinated notes: 4.00% subordinated notes due 2025 (a) 365 343 7.875% subordinated notes due 2026 (a) 207 198 Total subordinated notes 572 541 Medium- and long-term notes: 2.50% notes due 2020 (a) 672 663 2.50% notes due 2024 (a) 503 — Total medium- and long-term notes 1,175 663 Federal Home Loan Bank (FHLB) advances: Floating-rate based on FHLB auction rate due 2026 2,800 2,800 Floating-rate based on FHLB auction rate due 2028 1,000 1,000 Total FHLB advances 3,800 3,800 Total subsidiaries 5,547 5,004 Total medium- and long-term debt $ 7,311 $ 6,463 (a) The fixed interest rates on these notes have been swapped to a variable rate and designated in a hedging relationship. Accordingly, carrying value has been adjusted to reflect the change in the fair value of the debt as a result of changes in the benchmark rate.

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Loss (Tables)	9 Months Ended
	Sep. 30, 2019
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Schedule Of Accumulated Other Comprehensive Loss	The following table presents a reconciliation of the changes in the components of accumulated other comprehensive loss and details the components of other comprehensive income (loss) for the nine months ended September 30, 2019 and 2018 , including the amount of income tax expense (benefit) allocated to each component of other comprehensive income (loss). Nine Months Ended September 30, (in millions) 2019 2018 Accumulated net unrealized gains (losses) on investment securities: Balance at beginning of period, net of tax $ (138 ) $ (101 ) Cumulative effect of change in accounting principle — 1 Net unrealized holding gains (losses) arising during the period 267 (254 ) Less: Provision (benefit) for income taxes 62 (59 ) Net unrealized holding gains (losses) arising during the period, net of tax 205 (195 ) Less: Net realized losses included in net securities losses (8 ) (20 ) Less: Benefit for income taxes (2 ) (5 ) Reclassification adjustment for net securities losses included in net income, net of tax (6 ) (15 ) Change in net unrealized gains (losses) on investment securities, net of tax 211 (180 ) Balance at end of period, net of tax $ 73 $ (280 ) Accumulated net gains on cash flow hedges: Balance at beginning of period, net of tax $ — $ — Net cash flow hedge gains arising during the period 69 — Less: Provision for income taxes 16 — Change in net cash flow hedge gains arising during the period, net of tax 53 — Less: Net cash flow hedge losses included in interest and fees on loans (1 ) — Change in net cash flow hedge gains, net of tax 54 — Balance at end of period, net of tax (a) $ 54 $ — Accumulated defined benefit pension and other postretirement plans adjustment: Balance at beginning of period, net of tax $ (471 ) $ (350 ) Amortization of actuarial net loss 30 45 Amortization of prior service credit (20 ) (20 ) Amounts recognized in other noninterest expense 10 25 Less: Provision for income taxes 2 6 Change in defined benefit pension and other postretirement plans adjustment, net of tax 8 19 Balance at end of period, net of tax $ (463 ) $ (331 ) Total accumulated other comprehensive loss at end of period, net of tax $ (336 ) $ (611 )

Net Income Per Share (Tables)

Net Income Per Share (Tables)	9 Months Ended
	Sep. 30, 2019
Earnings Per Share [Abstract]
Basic And Diluted Net Income Per Share	Basic and diluted net income per share are presented in the following table. Three Months Ended September 30, Nine Months Ended September 30, (in millions, except per share data) 2019 2018 2019 2018 Basic and diluted Net income $ 292 $ 318 $ 929 $ 925 Less: Income allocated to participating securities 2 2 5 6 Net income attributable to shares $ 290 $ 316 $ 924 $ 919 Basic average shares 147 167 152 170 Basic net income per share $ 1.98 $ 1.89 $ 6.08 $ 5.41 Basic average shares 147 167 152 170 Dilutive stock equivalents: Net effect of the assumed exercise of stock options 1 2 2 2 Net effect of the assumed exercise of warrants — 1 — 1 Diluted average shares 148 170 154 173 Diluted net income per share $ 1.96 $ 1.86 $ 6.02 $ 5.32
Schedule of Average Shares Excluded from Diluted Net Income Per Share Computation	The following average shares related to outstanding options to purchase shares of stock were not included in the computation of diluted net income per share because the options were anti-dilutive for the period. Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Average outstanding options 814,044 — 570,433 — Range of exercise prices $67.53 - $95.25 — $67.53 - $95.25 —

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	9 Months Ended
	Sep. 30, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]
Components of Net Periodic Benefit Cost	The components of net periodic benefit cost (credit) for the Corporation's qualified pension plan, non-qualified pension plan and postretirement benefit plan are as follows. Qualified Defined Benefit Pension Plan Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2019 2018 2019 2018 Service cost $ 8 $ 7 $ 23 $ 22 Other components of net benefit credit: Interest cost 20 19 60 56 Expected return on plan assets (41 ) (41 ) (124 ) (123 ) Amortization of prior service credit (5 ) (5 ) (14 ) (14 ) Amortization of net loss 8 13 25 38 Total other components of net benefit credit (18 ) (14 ) (53 ) (43 ) Net periodic defined benefit credit $ (10 ) $ (7 ) $ (30 ) $ (21 ) Non-Qualified Defined Benefit Pension Plan Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2019 2018 2019 2018 Service cost $ — $ — $ 2 $ 1 Other components of net benefit cost: Interest cost 3 2 7 6 Amortization of prior service credit (2 ) (1 ) (6 ) (6 ) Amortization of net loss 1 2 5 7 Total other components of net benefit cost 2 3 6 7 Net periodic defined benefit cost $ 2 $ 3 $ 8 $ 8 Postretirement Benefit Plan Three Months Ended September 30, Nine Months Ended September 30, (in millions) 2019 2018 2019 2018 Other components of net benefit credit: Interest cost $ — $ — $ 1 $ 1 Expected return on plan assets (1 ) — (2 ) (2 ) Net periodic defined benefit credit $ (1 ) $ — $ (1 ) $ (1 )

Business Segment Information (T

Business Segment Information (Tables)	9 Months Ended
	Sep. 30, 2019
Segment Reporting [Abstract]
Business Segment Financial Results	Business segment financial results are as follows: Business Retail Wealth Management Finance Other Total (dollar amounts in millions) Three Months Ended September 30, 2019 Earnings summary: Net interest income (expense) $ 420 $ 142 $ 47 $ (38 ) $ 15 $ 586 Provision for credit losses 39 (2 ) (3 ) — 1 35 Noninterest income 140 31 69 12 4 256 Noninterest expenses 199 149 69 (1 ) 19 435 Provision (benefit) for income taxes 74 5 12 (8 ) (3 ) (a) 80 Net income (loss) $ 248 $ 21 $ 38 $ (17 ) $ 2 $ 292 Net credit-related charge-offs (recoveries) $ 43 $ 1 $ (2 ) $ — $ — $ 42 Selected average balances: Assets $ 45,459 $ 2,871 $ 5,032 $ 14,392 $ 3,982 $ 71,736 Loans 43,889 2,114 4,884 — — 50,887 Deposits 28,917 20,761 3,775 2,049 214 55,716 Statistical data: Return on average assets (b) 2.17 % 0.39 % 3.01 % n/m n/m 1.61 % Efficiency ratio (c) 35.62 84.54 59.79 n/m n/m 51.54 Three Months Ended September 30, 2018 Earnings summary: Net interest income (expense) $ 414 $ 140 $ 46 $ (16 ) $ 15 $ 599 Provision for credit losses — 1 1 — (2 ) — Noninterest income 137 35 66 (7 ) 3 234 Noninterest expenses 211 153 72 (1 ) 17 452 Provision (benefit) for income taxes 76 5 10 (8 ) (20 ) (a) 63 Net income (loss) $ 264 $ 16 $ 29 $ (14 ) $ 23 $ 318 Net credit-related charge-offs $ 14 $ — $ 1 $ — $ — $ 15 Selected average balances: Assets $ 43,165 $ 2,621 $ 5,068 $ 13,696 $ 6,660 $ 71,210 Loans 41,591 2,057 4,936 — — 48,584 Deposits 30,286 20,765 3,988 929 125 56,093 Statistical data: Return on average assets (b) 2.43 % 0.31 % 2.28 % n/m n/m 1.77 % Efficiency ratio (c) 38.24 86.96 63.93 n/m n/m 52.93 (a) Included discrete tax benefits of $5 million and $23 million for the three months ended September 30, 2019 and 2018 , respectively. (b) Return on average assets is calculated based on the greater of average assets or average liabilities and attributed equity. (c) Noninterest expenses as a percentage of the sum of net interest income and noninterest income excluding net gains (losses) from securities and a derivative contract tied to the conversion rate of Visa Class B shares. n/m – not meaningful (dollar amounts in millions) Business Retail Wealth Management Finance Other Total Nine Months Ended September 30, 2019 Earnings summary: Net interest income (expense) $ 1,252 $ 434 $ 140 $ (77 ) $ 46 $ 1,795 Provision for credit losses 85 (5 ) (13 ) — (1 ) 66 Noninterest income 412 95 201 30 6 744 Noninterest expenses 592 441 208 (1 ) 52 1,292 Provision (benefit) for income taxes 227 21 35 (16 ) (15 ) (a) 252 Net income (loss) $ 760 $ 72 $ 111 $ (30 ) $ 16 $ 929 Net credit-related charge-offs (recoveries) $ 90 $ 1 $ (5 ) $ — $ — $ 86 Selected average balances: Assets $ 44,902 $ 2,841 $ 5,092 $ 14,184 $ 3,908 $ 70,927 Loans 43,456 2,108 4,950 — — 50,514 Deposits 28,545 20,628 3,772 1,788 176 54,909 Statistical data: Return on average assets (b) 2.26 % 0.46 % 2.92 % n/m n/m 1.75 % Efficiency ratio (c) 35.61 82.70 61.04 n/m n/m 50.66 Nine Months Ended September 30, 2018 Earnings summary: Net interest income (expense) $ 1,200 $ 402 $ 133 $ (37 ) $ 40 $ 1,738 Provision for credit losses (9 ) (2 ) (2 ) — (4 ) (17 ) Noninterest income 403 100 201 16 6 726 Noninterest expenses 635 450 218 (3 ) 46 1,346 Provision (benefit) for income taxes 222 12 29 (13 ) (40 ) (a) 210 Net income (loss) $ 755 $ 42 $ 89 $ (5 ) $ 44 $ 925 Net credit-related charge-offs $ 40 $ — $ — $ — $ — $ 40 Selected average balances: Assets $ 43,205 $ 2,629 $ 5,233 $ 13,736 $ 5,886 $ 70,689 Loans 41,580 2,062 5,102 — — 48,744 Deposits 30,168 20,888 3,879 949 120 56,004 Statistical data: Return on average assets (b) 2.34 % 0.26 % 2.26 % n/m n/m 1.75 % Efficiency ratio (c) 39.59 89.03 65.51 n/m n/m 54.12 (a) Included discrete tax benefits of $16 million and $48 million for the nine months ended September 30, 2019 and 2018 , respectively. (b) Return on average assets is calculated based on the greater of average assets or average liabilities and attributed equity. (c) Noninterest expenses as a percentage of the sum of net interest income and noninterest income excluding gains (losses) from securities and a derivative contract tied to the conversion rate of Visa Class B shares.
Market Segment Financial Results	eview. Market segment financial results are as follows: Michigan California Texas Other Finance Total (dollar amounts in millions) Three Months Ended September 30, 2019 Earnings summary: Net interest income (expense) $ 185 $ 203 $ 125 $ 96 $ (23 ) $ 586 Provision for credit losses (1 ) (6 ) 50 (9 ) 1 35 Noninterest income 74 41 31 94 16 256 Noninterest expenses 139 102 86 90 18 435 Provision (benefit) for income taxes 27 37 5 22 (11 ) (a) 80 Net income (loss) $ 94 $ 111 $ 15 $ 87 $ (15 ) $ 292 Net credit-related charge-offs (recoveries) $ 6 $ 5 $ 34 $ (3 ) $ — $ 42 Selected average balances: Assets $ 13,213 $ 18,726 $ 11,462 $ 9,961 $ 18,374 $ 71,736 Loans 12,554 18,393 10,805 9,135 — 50,887 Deposits 20,164 16,725 8,705 7,859 2,263 55,716 Statistical data: Return on average assets (b) 1.78 % 2.37 % 0.48 % 3.47 % n/m 1.61 % Efficiency ratio (c) 53.31 41.64 55.57 47.19 n/m 51.54 Three Months Ended September 30, 2018 Earnings summary: Net interest income (expense) $ 185 $ 200 $ 120 $ 95 $ (1 ) $ 599 Provision for credit losses 4 3 (9 ) 4 (2 ) — Noninterest income 76 43 33 86 (4 ) 234 Noninterest expenses 144 106 89 97 16 452 Provision (benefit) for income taxes 25 34 16 16 (28 ) (a) 63 Net income $ 88 $ 100 $ 57 $ 64 $ 9 $ 318 Net credit-related charge-offs (recoveries) $ 8 $ 5 $ 3 $ (1 ) $ — $ 15 Selected average balances: Assets $ 13,055 $ 18,349 $ 10,263 $ 9,187 $ 20,356 $ 71,210 Loans 12,424 18,074 9,694 8,392 — 48,584 Deposits 20,720 16,894 8,902 8,523 1,054 56,093 Statistical data: Return on average assets (b) 1.63 % 2.18 % 2.18 % 2.74 % n/m 1.77 % Efficiency ratio (c) 54.96 43.10 58.06 54.02 n/m 52.93 (a) Included discrete tax benefits of $5 million and $23 million for the three months ended September 30, 2019 and 2018 , respectively. (b) Return on average assets is calculated based on the greater of average assets or average liabilities and attributed equity. (c) Noninterest expenses as a percentage of the sum of net interest income and noninterest income excluding net gains (losses) from securities and a derivative contract tied to the conversion rate of Visa Class B shares. n/m – not meaningful (dollar amounts in millions) Michigan California Texas Other Finance Total Nine Months Ended September 30, 2019 Earnings summary: Net interest income (expense) $ 557 $ 616 $ 372 $ 281 $ (31 ) $ 1,795 Provision for credit losses (6 ) (11 ) 88 (4 ) (1 ) 66 Noninterest income 218 121 97 272 36 744 Noninterest expenses 412 301 255 273 51 1,292 Provision (benefit) for income taxes 83 113 30 57 (31 ) (a) 252 Net income (loss) $ 286 $ 334 $ 96 $ 227 $ (14 ) $ 929 Net credit-related charge-offs (recoveries) $ 10 $ 9 $ 73 $ (6 ) $ — $ 86 Selected average balances: Assets $ 13,176 $ 19,000 $ 11,240 $ 9,419 $ 18,092 $ 70,927 Loans 12,605 18,695 10,586 8,628 — 50,514 Deposits 19,959 16,433 8,690 7,863 1,964 54,909 Statistical data: Return on average assets (b) 1.85 % 2.36 % 1.13 % 3.23 % n/m 1.75 % Efficiency ratio (c) 53.00 40.82 54.35 49.33 n/m 50.66 Nine Months Ended September 30, 2018 Earnings summary: Net interest income $ 540 $ 582 $ 353 $ 260 $ 3 $ 1,738 Provision for credit losses 38 (8 ) (37 ) (6 ) (4 ) (17 ) Noninterest income 222 124 94 264 22 726 Noninterest expenses 432 316 273 282 43 1,346 Provision (benefit) for income taxes 67 101 48 47 (53 ) (a) 210 Net income $ 225 $ 297 $ 163 $ 201 $ 39 $ 925 Net credit-related charge-offs $ 7 $ 18 $ 11 $ 4 $ — $ 40 Selected average balances: Assets $ 13,291 $ 18,542 $ 10,352 $ 8,882 $ 19,622 $ 70,689 Loans 12,556 18,284 9,789 8,115 — 48,744 Deposits 20,947 16,875 9,016 8,097 1,069 56,004 Statistical data: Return on average assets (b) 1.39 % 2.14 % 2.10 % 3.03 % n/m 1.75 % Efficiency ratio (c) 56.50 44.76 60.92 53.91 n/m 54.12 (a) Included discrete tax benefits of $16 million and $48 million for the nine months ended September 30, 2019 and 2018 , respectively. (b) Return on average assets is calculated based on the greater of average assets or average liabilities and attributed equity. (c) Noninterest expenses as a percentage of the sum of net interest income and noninterest income excluding gains (losses) from securities and a derivative contract tied to the conversion rate of Visa Class B shares. n/m – not meaningful

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	9 Months Ended
	Sep. 30, 2019
Revenue from Contract with Customer [Abstract]
Composition of Revenue from Contracts with Customers	The following table presents the composition of revenue from contracts with customers, segregated from other sources of noninterest income, by business segment. Business Bank Retail Bank Wealth Management Finance & Other Total (in millions) Three Months Ended September 30, 2019 Revenue from contracts with customers: Card fees $ 55 $ 11 $ 1 $ — $ 67 Service charges on deposit accounts 32 18 1 — 51 Fiduciary income — — 53 — 53 Commercial loan servicing fees (a) 5 — — — 5 Brokerage fees — — 7 — 7 Other noninterest income (b) 1 1 5 — 7 Total revenue from contracts with customers 93 30 67 — 190 Other sources of noninterest income 47 1 2 16 66 Total noninterest income $ 140 $ 31 $ 69 $ 16 $ 256 Three Months Ended September 30, 2018 Revenue from contracts with customers: Card fees $ 50 $ 10 $ 1 $ — $ 61 Service charges on deposit accounts 34 18 1 — 53 Fiduciary income — — 51 — 51 Commercial loan servicing fees (a) 5 — — — 5 Brokerage fees — — 7 — 7 Other noninterest income (b) 3 6 4 — 13 Total revenue from contracts with customers 92 34 64 — 190 Other sources of noninterest income 45 1 2 (4 ) 44 Total noninterest income $ 137 $ 35 $ 66 $ (4 ) $ 234 Nine Months Ended September 30, 2019 Revenue from contracts with customers: Card fees $ 162 $ 30 $ 3 $ — $ 195 Service charges on deposit accounts 98 52 3 — 153 Fiduciary income — — 154 — 154 Commercial loan servicing fees (a) 13 — — — 13 Brokerage fees — — 21 — 21 Other noninterest income (b) 5 8 14 — 27 Total revenue from contracts with customers 278 90 195 — 563 Other sources of noninterest income 134 5 6 36 181 Total noninterest income $ 412 $ 95 $ 201 $ 36 $ 744 Nine Months Ended September 30, 2018 Revenue from contracts with customers: Card fees $ 149 $ 28 $ 3 $ — $ 180 Service charges on deposit accounts 102 54 4 — 160 Fiduciary income — — 155 — 155 Commercial loan servicing fees (a) 14 — — — 14 Brokerage fees — — 20 — 20 Other noninterest income (b) 9 13 12 — 34 Total revenue from contracts with customers 274 95 194 — 563 Other sources of noninterest income 129 5 7 22 163 Total noninterest income $ 403 $ 100 $ 201 $ 22 $ 726 (a) Included in commercial lending fees on the Consolidated Statements of Comprehensive Income. (b) Excludes derivative, warrant and other miscellaneous income.

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2019
Leases (Narrative) [Abstract]
Contractual Maturities of Operating Lease Liabilities	As of September 30, 2019 , the contractual maturities of operating lease liabilities were as follows: (in millions) Years Ending December 31 2019 (a) $ 10 2020 64 2021 59 2022 50 2023 44 Thereafter 204 Total contractual maturities 431 Less imputed interest (73 ) Total operating lease liabilities $ 358 (a) Contractual maturities for the three months remaining in 2019 .
Contractual Maturities of Sales-Type and Direct-Financing Lease Receivables	As of September 30, 2019 , the contractual maturities of sales-type and direct financing lease receivables were as follows: (in millions) Years Ending December 31 2019 (a) $ 18 2020 63 2021 52 2022 88 2023 39 Thereafter 58 Total lease payments receivable 318 Unguaranteed residual values 64 Less deferred interest income (21 ) Total lease receivables (b) $ 361 (a) Contractual maturities for the three months remaining in 2019 . (b) Excludes net investment in leveraged leases of $217 million .

Basis of Presentation and Acc_3

Basis of Presentation and Accounting Policies Basis of Presentation and Accounting Policies (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Jan. 01, 2019
Right of use assets	$ 320
Operating lease liabilities	$ 358
Accounting Standards Update 2016-02
Right of use assets		$ 329
Operating lease liabilities		343
Cumulative effect of change in accounting principle		$ 14

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Recurring
Transfers into or out of Level 1 or Level 2 or Level 3	$ 0	$ 0	$ 0	$ 0
Total liabilities at fair value	301		301		$ 357
Nonrecurring
Total liabilities at fair value	$ 0		$ 0		$ 0

Fair Value Measurements (Assets

Fair Value Measurements (Assets And Liabilities Recorded At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Millions		Sep. 30, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale		$ 12,429	$ 12,045
Derivative assets		448	275
Derivative liabilities		209	269
U.S. Treasury and other U.S. government agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale		2,796	2,727
Residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	[1]	9,633	9,318
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale		12,429	12,045
Derivative assets		448	275
Total assets at fair value		13,018	12,451
Derivative liabilities		209	269
Deferred compensation plan liabilities		92	88
Total liabilities at fair value		301	357
Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale		2,796	2,727
Derivative assets		0	0
Total assets at fair value		2,937	2,858
Derivative liabilities		0	0
Deferred compensation plan liabilities		92	88
Total liabilities at fair value		92	88
Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale		9,633	9,318
Derivative assets		420	266
Total assets at fair value		10,053	9,584
Derivative liabilities		209	269
Deferred compensation plan liabilities		0	0
Total liabilities at fair value		209	269
Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale		0	0
Derivative assets		28	9
Total assets at fair value		28	9
Derivative liabilities		0	0
Deferred compensation plan liabilities		0	0
Total liabilities at fair value		0	0
Recurring | Interest rate contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		275	67
Derivative liabilities		43	70
Recurring | Interest rate contracts | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		0	0
Derivative liabilities		0	0
Recurring | Interest rate contracts | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		247	58
Derivative liabilities		43	70
Recurring | Interest rate contracts | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		28	9
Derivative liabilities		0	0
Recurring | Energy derivative contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		160	189
Derivative liabilities		156	186
Recurring | Energy derivative contracts | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		0	0
Derivative liabilities		0	0
Recurring | Energy derivative contracts | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		160	189
Derivative liabilities		156	186
Recurring | Energy derivative contracts | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		0	0
Derivative liabilities		0	0
Recurring | Foreign exchange contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		13	19
Derivative liabilities		10	13
Recurring | Foreign exchange contracts | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		0	0
Derivative liabilities		0	0
Recurring | Foreign exchange contracts | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		13	19
Derivative liabilities		10	13
Recurring | Foreign exchange contracts | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		0	0
Derivative liabilities		0	0
Recurring | Deferred compensation plan assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities		92	88
Recurring | Deferred compensation plan assets | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities		92	88
Recurring | Deferred compensation plan assets | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities		0	0
Recurring | Deferred compensation plan assets | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities		0	0
Recurring | Equity and other non-debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other equity securities		49	43
Recurring | Equity and other non-debt securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other equity securities		49	43
Recurring | Equity and other non-debt securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other equity securities		0	0
Recurring | Equity and other non-debt securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other equity securities		0	0
Recurring | U.S. Treasury and other U.S. government agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale		2,796	2,727
Recurring | U.S. Treasury and other U.S. government agency securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale		2,796	2,727
Recurring | U.S. Treasury and other U.S. government agency securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale		0	0
Recurring | U.S. Treasury and other U.S. government agency securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale		0	0
Recurring | Residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	[1]	9,633	9,318
Recurring | Residential mortgage-backed securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	[1]	0	0
Recurring | Residential mortgage-backed securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	[1]	9,633	9,318
Recurring | Residential mortgage-backed securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	[1]	$ 0	$ 0
[1]	Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises.

Fair Value Measurements (Change

Fair Value Measurements (Changes In Level 3 Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jan. 01, 2018
Change in classification		$ 0	$ (81)	$ 0	$ (81)
Interest rate contracts
Balance at beginning of period		21	6	9	14
Change in classification		0	0	0	0
Realized gains (losses) recorded in earnings	[1]	1	0	1	0
Unrealized gains (losses) recorded in earnings	[1]	7	(4)	19	(12)
Payments, sales and redemptions		(1)	0	(1)	0
Balance at end of period		$ 28	2	$ 28	2
Investment Securities Available-For-Sale
Balance at beginning of period					49
Change in classification	[2]					$ (44)
Realized gains (losses) recorded in earnings	[1]				0
Unrealized gains (losses) recorded in earnings	[1]				0
Payments, sales and redemptions					(5)
Balance at end of period			0		0
Equity and other non-debt securities | Equity and other non-debt securities
Balance at beginning of period					0
Change in classification	[2]					(44)
Realized gains (losses) recorded in earnings	[1]				0
Unrealized gains (losses) recorded in earnings	[1]				0
Payments, sales and redemptions					(44)
Balance at end of period			0		0
Equity and other non-debt securities | Investment Securities Available-For-Sale
Balance at beginning of period	[3]				44
Change in classification	[2],[3]					$ (44)
Realized gains (losses) recorded in earnings	[1],[3]				0
Unrealized gains (losses) recorded in earnings	[1],[3]				0
Payments, sales and redemptions	[3]				0
Balance at end of period	[3]		0		0
State and municipal securities | Investment Securities Available-For-Sale
Balance at beginning of period	[3]				5
Change in classification	[3]		0		0
Realized gains (losses) recorded in earnings	[1],[3]				0
Unrealized gains (losses) recorded in earnings	[1],[3]				0
Payments, sales and redemptions					(5)
Balance at end of period	[3]		$ 0		$ 0
[1]	Realized and unrealized gains and losses due to changes in fair value are recorded in other noninterest income on the Consolidated Statements of Comprehensive Income.
[2]	Reflects the reclassification of equity securities resulting from the adoption of ASU 2016-01.
[3]	Auction-rate securities.

Fair Value Measurements (Asse_2

Fair Value Measurements (Assets And Liabilities Recorded At Fair Value On A Nonrecurring Basis) (Details) - Nonrecurring - Level 3 - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	$ 25	$ 35
Commercial borrower | Domestic loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans	$ 25	33
Commercial borrower | Commercial mortgage | Domestic loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans		$ 2

Fair Value Measurements (Estima

Fair Value Measurements (Estimated Fair Values Of Financial Instruments Not Recorded At Fair Value In Their Entirety On A Recurring Basis) (Details) - USD ($) $ in Millions		Sep. 30, 2019	Dec. 31, 2018
Cash and due from banks		$ 1,229	$ 1,390
Interest-bearing deposits with banks		2,888	3,171
Total loans, net of allowance for loan losses		50,839	49,492
Demand deposits (noninterest-bearing)		27,134	28,690
Customer certificates of deposit		2,853	2,131
Other time deposits		647	0
Total deposits		56,809	55,561
Short-term borrowings		51	44
Medium- and long-term debt		7,311	6,463
Carrying Amount
Cash and due from banks		1,229	1,390
Interest-bearing deposits with banks		2,888	3,171
Loans held-for-sale		4	3
Total loans, net of allowance for loan losses	[1]	50,839	49,492
Customers' liability on acceptances outstanding		2	4
Restricted equity investments		248	248
Nonmarketable equity securities	[2]	6	6
Demand deposits (noninterest-bearing)		27,134	28,690
Interest-bearing deposits		26,175	24,740
Customer certificates of deposit		2,853	2,131
Other time deposits		647
Total deposits		56,809	55,561
Short-term borrowings		51	44
Acceptances outstanding		2	4
Medium- and long-term debt		7,311	6,463
Credit-related financial instruments		(56)	(57)
Estimated Fair Value
Cash and due from banks		1,229	1,390
Interest-bearing deposits with banks		2,888	3,171
Loans held-for-sale		4	3
Total loans, net of allowance for loan losses	[1]	51,008	48,889
Customers' liability on acceptances outstanding		2	4
Restricted equity investments		248	248
Nonmarketable equity securities	[2]	10	11
Demand deposits (noninterest-bearing)		27,134	28,690
Interest-bearing deposits		26,175	24,740
Customer certificates of deposit		2,842	2,100
Other time deposits		647
Total deposits		56,798	55,530
Short-term borrowings		51	44
Acceptances outstanding		2	4
Medium- and long-term debt		7,316	6,436
Credit-related financial instruments		(56)	(57)
Level 1 | Estimated Fair Value
Cash and due from banks		1,229	1,390
Interest-bearing deposits with banks		2,888	3,171
Loans held-for-sale		0	0
Total loans, net of allowance for loan losses	[1]	0	0
Customers' liability on acceptances outstanding		2	4
Restricted equity investments		248	248
Demand deposits (noninterest-bearing)		0	0
Interest-bearing deposits		0	0
Customer certificates of deposit		0	0
Other time deposits		0
Total deposits		0	0
Short-term borrowings		51	44
Acceptances outstanding		2	4
Medium- and long-term debt		0	0
Credit-related financial instruments		0	0
Level 2 | Estimated Fair Value
Cash and due from banks		0	0
Interest-bearing deposits with banks		0	0
Loans held-for-sale		4	3
Total loans, net of allowance for loan losses	[1]	0	0
Customers' liability on acceptances outstanding		0	0
Restricted equity investments		0	0
Demand deposits (noninterest-bearing)		27,134	28,690
Interest-bearing deposits		26,175	24,740
Customer certificates of deposit		2,842	2,100
Other time deposits		647
Total deposits		56,798	55,530
Short-term borrowings		0	0
Acceptances outstanding		0	0
Medium- and long-term debt		7,316	6,436
Credit-related financial instruments		0	0
Level 3 | Estimated Fair Value
Cash and due from banks		0	0
Interest-bearing deposits with banks		0	0
Loans held-for-sale		0	0
Total loans, net of allowance for loan losses	[1]	51,008	48,889
Customers' liability on acceptances outstanding		0	0
Restricted equity investments		0	0
Demand deposits (noninterest-bearing)		0	0
Interest-bearing deposits		0	0
Customer certificates of deposit		0	0
Other time deposits		0
Total deposits		0	0
Short-term borrowings		0	0
Acceptances outstanding		0	0
Medium- and long-term debt		0	0
Credit-related financial instruments		(56)	(57)
Nonrecurring
Total loans, net of allowance for loan losses		$ 25	$ 35
[1]	Included $25 million and $35 million of impaired loans recorded at fair value on a nonrecurring basis at September 30, 2019 and December 31, 2018 , respectively.
[2]	Certain investments that are measured at fair value using the net asset value have not been classified in the fair value hierarchy. The fair value amounts presented in the table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the Consolidated Balance Sheets.

Investment Securities (Narrativ

Investment Securities (Narrative) (Details) $ in Millions		9 Months Ended
		Sep. 30, 2019USD ($)Security	Sep. 30, 2018USD ($)	Dec. 31, 2018USD ($)
Residential mortgage-backed securities transferred from held-to-maturity to available-for-sale		$ 0	$ 1,266
Investment securities available-for-sale, Amortized Cost		12,334		$ 12,225
Investment securities available-for-sale, Fair Value		12,429		12,045
Carrying value of securities pledged		375
Liabilities secured by pledged collateral		270
U.S. Treasury and other U.S. government agency securities
Investment securities available-for-sale, Amortized Cost		2,744		2,732
Investment securities available-for-sale, Fair Value		$ 2,796		2,727
Residential mortgage-backed securities
Securities with no credit impairment in unrealized loss position | Security		178
Investment securities available-for-sale, Amortized Cost	[1]	$ 9,590		9,493
Investment securities available-for-sale, Fair Value	[1]	9,633		$ 9,318
Debt securities
Investment securities available-for-sale, Amortized Cost		12,334
Investment securities available-for-sale, Fair Value		12,429
Prepayment options | Residential mortgage-backed securities
Investment securities available-for-sale, Amortized Cost	[1]	9,590
Investment securities available-for-sale, Fair Value	[1]	$ 9,600
[1]	Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises.

Investment Securities (Summary

Investment Securities (Summary Of Investment Securities) (Details) - USD ($) $ in Millions		Sep. 30, 2019	Dec. 31, 2018
Investment securities available-for-sale, Amortized Cost		$ 12,334	$ 12,225
Investment securities available-for-sale securities, Gross Unrealized Gains		126	36
Investment securities available-for-sale securities, Gross Unrealized Losses		31	216
Investment securities available-for-sale, Fair Value		12,429	12,045
U.S. Treasury and other U.S. government agency securities
Investment securities available-for-sale, Amortized Cost		2,744	2,732
Investment securities available-for-sale securities, Gross Unrealized Gains		52	14
Investment securities available-for-sale securities, Gross Unrealized Losses		0	19
Investment securities available-for-sale, Fair Value		2,796	2,727
Residential mortgage-backed securities
Investment securities available-for-sale, Amortized Cost	[1]	9,590	9,493
Investment securities available-for-sale securities, Gross Unrealized Gains	[1]	74	22
Investment securities available-for-sale securities, Gross Unrealized Losses	[1]	31	197
Investment securities available-for-sale, Fair Value	[1]	$ 9,633	$ 9,318
[1]	Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises.

Investment Securities (Summar_2

Investment Securities (Summary Of Investment Securities In Unrealized Loss Positions) (Details) - USD ($) $ in Millions		Sep. 30, 2019	Dec. 31, 2018
Temporarily Impaired Less than 12 months, Fair Value		$ 1,412	$ 1,008
Temporarily Impaired Less than 12 Months, Unrealized Losses		4	9
Temporarily Impaired 12 months or more, Fair Value		2,130	7,869
Temporarily Impaired 12 Months or more, Unrealized Losses		27	207
Temporarily Impaired Total, Fair Value		3,542	8,877
Temporarily Impaired Total, Unrealized Losses		31	216
U.S. Treasury and other U.S. government agency securities
Temporarily Impaired Less than 12 months, Fair Value			0
Temporarily Impaired Less than 12 Months, Unrealized Losses			0
Temporarily Impaired 12 months or more, Fair Value			1,457
Temporarily Impaired 12 Months or more, Unrealized Losses			19
Temporarily Impaired Total, Fair Value			1,457
Temporarily Impaired Total, Unrealized Losses			19
Residential mortgage-backed securities
Temporarily Impaired Less than 12 months, Fair Value	[1]	1,412	1,008
Temporarily Impaired Less than 12 Months, Unrealized Losses	[1]	4	9
Temporarily Impaired 12 months or more, Fair Value	[1]	2,130	6,412
Temporarily Impaired 12 Months or more, Unrealized Losses	[1]	27	188
Temporarily Impaired Total, Fair Value	[1]	3,542	7,420
Temporarily Impaired Total, Unrealized Losses	[1]	$ 31	$ 197
[1]	Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises.

Investment Securities Investmen

Investment Securities Investment Securities (Summary of Net Securities Gains (Losses)) (Details) - Debt securities - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Investments, Debt, and Equity Securities [Abstract]
Securities gains	$ 0	$ 0	$ 0	$ 1
Securities losses	0	(20)	(8)	(20)
Net securities losses	$ 0	$ (20)	$ (8)	$ (19)

Investment Securities (Contract

Investment Securities (Contractual Maturity Distribution Of Debt Securities) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Investment securities available-for-sale, Amortized Cost	$ 12,334	$ 12,225
Investment securities available-for-sale, Fair Value	12,429	$ 12,045
Debt securities
Available-for-sale, Within one year, Amortized Cost	30
Available-for-sale, After one year through five years, Amortized Cost	2,818
Available-for-sale, After five years through ten years, Amortized Cost	1,127
Available-for-sale, After ten years, Amortized Cost	8,359
Investment securities available-for-sale, Amortized Cost	12,334
Available-for-sale, Within one year, Fair Value	31
Available-for-sale, After one year through five years, Fair Value	2,874
Available-for-sale, After five years through ten years, Fair Value	1,134
Available-for-sale, After ten years, Fair Value	8,390
Investment securities available-for-sale, Fair Value	$ 12,429

Credit Quality And Allowance _3

Credit Quality And Allowance For Credit Losses (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Retail loans secured by residential real estate in process of foreclosure	$ 0		$ 0		$ 1
Commitments to lend additional funds to TDR borrowers	2		$ 2		$ 20
Principal Deferrals
Minimum period loan terms were extended			90 days	90 days
Balance	19	$ 64	$ 19	$ 64
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	17	0	17	0
Interest Rate Reductions
Balance	1	3	1	3
Financing Receivable, Troubled Debt Restructuring, Subsequent Default	$ 0	$ 0	$ 0	$ 0

Credit Quality And Allowance _4

Credit Quality And Allowance For Credit Losses (Aging Analysis Of Loans) (Details) - USD ($) $ in Millions		Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		$ 169	$ 149
Nonaccrual loans		220	221
Current loans		51,102	49,793
Total loans		51,491	50,163
30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		103	98
60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		35	35
90 days or more past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		31	16
Business loans | Commercial borrower
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		149	129
Nonaccrual loans		167	166
Current loans		46,818	45,384
Total loans		47,134	45,679
Business loans | Commercial borrower | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		87	82
Business loans | Commercial borrower | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		31	31
Business loans | Commercial borrower | 90 days or more past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		31	16
Business loans | Commercial borrower | Domestic loans
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		100	68
Nonaccrual loans		152	141
Current loans		32,638	31,767
Total loans		32,890	31,976
Business loans | Commercial borrower | Domestic loans | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		44	34
Business loans | Commercial borrower | Domestic loans | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		28	26
Business loans | Commercial borrower | Domestic loans | 90 days or more past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		28	8
Business loans | Commercial borrower | International loans
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		1	0
Nonaccrual loans		2	3
Current loans		1,052	1,010
Total loans		1,055	1,013
Business loans | Commercial borrower | International loans | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		0	0
Business loans | Commercial borrower | International loans | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		0	0
Business loans | Commercial borrower | International loans | 90 days or more past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		1	0
Business loans | Real estate construction | Commercial borrower | Domestic loans
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		1	12
Nonaccrual loans		0	0
Current loans		3,376	3,065
Total loans		3,377	3,077
Business loans | Real estate construction | Commercial borrower | Domestic loans | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		1	12
Business loans | Real estate construction | Commercial borrower | Domestic loans | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | 90 days or more past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Commercial Real Estate business line
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing	[1]	1	6
Nonaccrual loans	[1]	0	0
Current loans	[1]	2,989	2,681
Total loans	[1]	2,990	2,687
Business loans | Real estate construction | Commercial borrower | Domestic loans | Commercial Real Estate business line | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing	[1]	1	6
Business loans | Real estate construction | Commercial borrower | Domestic loans | Commercial Real Estate business line | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing	[1]	0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Commercial Real Estate business line | 90 days or more past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing	[1]	0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing	[2]	0	6
Nonaccrual loans	[2]	0	0
Current loans	[2]	387	384
Total loans	[2]	387	390
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing	[2]	0	6
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing	[2]	0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines | 90 days or more past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing	[2]	0	0
Business loans | Commercial mortgage | Commercial borrower | Domestic loans
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		47	49
Nonaccrual loans		13	20
Current loans		9,174	9,037
Total loans		9,234	9,106
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		42	36
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		3	5
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | 90 days or more past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		2	8
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing	[1]	5	4
Nonaccrual loans	[1]	2	2
Current loans	[1]	1,941	1,737
Total loans	[1]	1,948	1,743
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing	[1]	5	4
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing	[1]	0	0
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line | 90 days or more past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing	[1]	0	0
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing	[2]	42	45
Nonaccrual loans	[2]	11	18
Current loans	[2]	7,233	7,300
Total loans	[2]	7,286	7,363
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Other business lines | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing	[2]	37	32
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Other business lines | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing	[2]	3	5
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Other business lines | 90 days or more past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing	[2]	2	8
Business loans | Lease financing | Commercial borrower | Domestic loans
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		0	0
Nonaccrual loans		0	2
Current loans		578	505
Total loans		578	507
Business loans | Lease financing | Commercial borrower | Domestic loans | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		0	0
Business loans | Lease financing | Commercial borrower | Domestic loans | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		0	0
Business loans | Lease financing | Commercial borrower | Domestic loans | 90 days or more past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		0	0
Retail loans
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		20	20
Nonaccrual loans		53	55
Current loans		4,284	4,409
Total loans		4,357	4,484
Retail loans | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		16	16
Retail loans | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		4	4
Retail loans | 90 days or more past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		0	0
Retail loans | Consumer borrower
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		7	6
Nonaccrual loans		17	19
Current loans		2,427	2,489
Total loans		2,451	2,514
Retail loans | Consumer borrower | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		6	5
Retail loans | Consumer borrower | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		1	1
Retail loans | Consumer borrower | 90 days or more past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		0	0
Retail loans | Residential mortgage
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		13	14
Nonaccrual loans		36	36
Current loans		1,857	1,920
Total loans		1,906	1,970
Retail loans | Residential mortgage | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		10	11
Retail loans | Residential mortgage | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		3	3
Retail loans | Residential mortgage | 90 days or more past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		0	0
Retail loans | Home equity | Consumer borrower
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		5	5
Nonaccrual loans		17	19
Current loans		1,700	1,741
Total loans		1,722	1,765
Retail loans | Home equity | Consumer borrower | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		4	4
Retail loans | Home equity | Consumer borrower | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		1	1
Retail loans | Home equity | Consumer borrower | 90 days or more past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		0	0
Retail loans | Other consumer | Consumer borrower
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		2	1
Nonaccrual loans		0	0
Current loans		727	748
Total loans		729	749
Retail loans | Other consumer | Consumer borrower | 30 to 59 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		2	1
Retail loans | Other consumer | Consumer borrower | 60 to 89 days past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		0	0
Retail loans | Other consumer | Consumer borrower | 90 days or more past due and still accruing
Financing Receivable, Past Due [Line Items]
Loans past due and still accruing		$ 0	$ 0
[1]	Primarily loans to real estate developers.
[2]	Primarily loans secured by owner-occupied real estate.

Credit Quality And Allowance _5

Credit Quality And Allowance For Credit Losses (Loans By Credit Quality Indicator) (Details) - USD ($) $ in Millions		Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		$ 51,491	$ 50,163
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[1]	49,630	48,615
Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[2]	914	638
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	727	689
Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[4]	220	221
Business loans | Commercial borrower
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		47,134	45,679
Business loans | Commercial borrower | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[1]	45,341	44,198
Business loans | Commercial borrower | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[2]	905	634
Business loans | Commercial borrower | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	721	681
Business loans | Commercial borrower | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[4]	167	166
Business loans | Commercial borrower | Domestic loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		32,890	31,976
Business loans | Commercial borrower | Domestic loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[1]	31,420	30,817
Business loans | Commercial borrower | Domestic loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[2]	724	464
Business loans | Commercial borrower | Domestic loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	594	554
Business loans | Commercial borrower | Domestic loans | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[4]	152	141
Business loans | Commercial borrower | International loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		1,055	1,013
Business loans | Commercial borrower | International loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[1]	1,025	996
Business loans | Commercial borrower | International loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[2]	23	4
Business loans | Commercial borrower | International loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	5	10
Business loans | Commercial borrower | International loans | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[4]	2	3
Business loans | Real estate construction | Commercial borrower | Domestic loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		3,377	3,077
Business loans | Real estate construction | Commercial borrower | Domestic loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[1]	3,341	3,046
Business loans | Real estate construction | Commercial borrower | Domestic loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[2]	36	31
Business loans | Real estate construction | Commercial borrower | Domestic loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[4]	0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Commercial Real Estate business line
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[5]	2,990	2,687
Business loans | Real estate construction | Commercial borrower | Domestic loans | Commercial Real Estate business line | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[1],[5]	2,954	2,664
Business loans | Real estate construction | Commercial borrower | Domestic loans | Commercial Real Estate business line | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[2],[5]	36	23
Business loans | Real estate construction | Commercial borrower | Domestic loans | Commercial Real Estate business line | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3],[5]	0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Commercial Real Estate business line | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[4],[5]	0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[6]	387	390
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[1],[6]	387	382
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[2],[6]	0	8
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3],[6]	0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[4],[6]	0	0
Business loans | Commercial mortgage | Commercial borrower | Domestic loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		9,234	9,106
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[1]	8,989	8,839
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[2]	112	132
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	120	115
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[4]	13	20
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[5]	1,948	1,743
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[1],[5]	1,892	1,682
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[2],[5]	13	14
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3],[5]	41	45
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[4],[5]	2	2
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[6]	7,286	7,363
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Other business lines | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[1],[6]	7,097	7,157
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Other business lines | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[2],[6]	99	118
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Other business lines | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3],[6]	79	70
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Other business lines | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[4],[6]	11	18
Business loans | Lease financing | Commercial borrower | Domestic loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		578	507
Business loans | Lease financing | Commercial borrower | Domestic loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[1]	566	500
Business loans | Lease financing | Commercial borrower | Domestic loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[2]	10	3
Business loans | Lease financing | Commercial borrower | Domestic loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	2	2
Business loans | Lease financing | Commercial borrower | Domestic loans | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[4]	0	2
Retail loans
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		4,357	4,484
Retail loans | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[1]	4,289	4,417
Retail loans | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[2]	9	4
Retail loans | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	6	8
Retail loans | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[4]	53	55
Retail loans | Consumer borrower
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		2,451	2,514
Retail loans | Consumer borrower | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[1]	2,421	2,486
Retail loans | Consumer borrower | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[2]	7	1
Retail loans | Consumer borrower | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	6	8
Retail loans | Consumer borrower | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[4]	17	19
Retail loans | Residential mortgage
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		1,906	1,970
Retail loans | Residential mortgage | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[1]	1,868	1,931
Retail loans | Residential mortgage | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[2]	2	3
Retail loans | Residential mortgage | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	0	0
Retail loans | Residential mortgage | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[4]	36	36
Retail loans | Home equity | Consumer borrower
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		1,722	1,765
Retail loans | Home equity | Consumer borrower | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[1]	1,698	1,738
Retail loans | Home equity | Consumer borrower | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[2]	1	0
Retail loans | Home equity | Consumer borrower | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	6	8
Retail loans | Home equity | Consumer borrower | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[4]	17	19
Retail loans | Other consumer | Consumer borrower
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		729	749
Retail loans | Other consumer | Consumer borrower | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[1]	723	748
Retail loans | Other consumer | Consumer borrower | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[2]	6	1
Retail loans | Other consumer | Consumer borrower | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[3]	0	0
Retail loans | Other consumer | Consumer borrower | Nonaccrual
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	[4]	$ 0	$ 0
[1]	Includes all loans not included in the categories of special mention, substandard or nonaccrual.
[2]	Special mention loans are accruing loans that have potential credit weaknesses that deserve management’s close attention, such as loans to borrowers who may be experiencing financial difficulties that may result in deterioration of repayment prospects from the borrower at some future date. This category is generally consistent with the "special mention" category as defined by regulatory authorities.
[3]	Substandard loans are accruing loans that have a well-defined weakness, or weaknesses, such as loans to borrowers who may be experiencing losses from operations or inadequate liquidity of a degree and duration that jeopardizes the orderly repayment of the loan. Substandard loans also are distinguished by the distinct possibility of loss in the future if these weaknesses are not corrected. This category is generally consistent with the "substandard" category as defined by regulatory authorities.
[4]	Nonaccrual loans are loans for which the accrual of interest has been discontinued. For further information regarding nonaccrual loans, refer to the Nonperforming Assets subheading in Note 1 - Basis of Presentation and Accounting Policies - on pages F-52 and F-53 in the Corporation's 2018 Annual Report. A significant majority of nonaccrual loans are generally consistent with the "substandard" category and the remainder are generally consistent with the "doubtful" category as defined by regulatory authorities.
[5]	Primarily loans to real estate developers.
[6]	Primarily loans secured by owner-occupied real estate.

Credit Quality And Allowance _6

Credit Quality And Allowance For Credit Losses (Schedule Of Nonaccrual, Reduced-Rate Loans And Foreclosed Property) (Details) - USD ($) $ in Millions		Sep. 30, 2019	Dec. 31, 2018
Nonaccrual loans		$ 220	$ 221
Reduced-rate loans	[1]	6	8
Total nonperforming loans		226	229
Foreclosed property		3	1
Total nonperforming assets		229	230
Business loans
Reduced-rate loans		0	0
Retail loans
Nonaccrual loans		53	55
Reduced-rate loans		$ 6	$ 8
[1]	Comprised of reduced-rate retail loans

Credit Quality And Allowance _7

Credit Quality And Allowance For Credit Losses (Changes In The Allowance For Loan Losses And Related Loan Amounts) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
Provision for loan losses	$ (35)	$ 0	$ (66)	$ 17
Total loans					$ 51,491	$ 50,163
Financing Receivable
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance at beginning of period	657	677	671	712
Loan charge-offs	(61)	(25)	(125)	(82)
Recoveries on loans previously charged-off	19	10	39	42
Net loan recoveries (charge-offs)	(42)	(15)	(86)	(40)
Provision for loan losses	37	1	67	(8)
Allowance for Loan and Lease Losses, Foreign Currency Translation	0	(1)
Balance at end of period	652	664	652	664
As a percentage of total loans					1.27%		1.35%
Allowance for loan losses individually evaluated for impairment					$ 34		$ 29
Allowance for loan losses collectively evaluated for impairment					618		635
Total allowance for loan losses	657	677	671	712	652	671	664
Loans individually evaluated for impairment					243		303
Loans collectively evaluated for impairment					51,248		48,707
Total loans					$ 51,491		$ 49,010
Business loans | Financing Receivable
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance at beginning of period	618	635	627	661
Loan charge-offs	(59)	(24)	(121)	(78)
Recoveries on loans previously charged-off	17	9	35	39
Net loan recoveries (charge-offs)	(42)	(15)	(86)	(39)
Provision for loan losses	39	(1)	74	(2)
Allowance for Loan and Lease Losses, Foreign Currency Translation	0	(1)
Balance at end of period	615	620	615	620
As a percentage of total loans					1.30%		1.39%
Allowance for loan losses individually evaluated for impairment					$ 34		$ 29
Allowance for loan losses collectively evaluated for impairment					581		591
Total allowance for loan losses	618	635	615	661	615	627	620
Loans individually evaluated for impairment					209		269
Loans collectively evaluated for impairment					46,925		44,358
Total loans					47,134		$ 44,627
Retail loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Total loans					$ 4,357	4,484
Retail loans | Financing Receivable
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance at beginning of period	39	42	44	51
Loan charge-offs	(2)	(1)	(4)	(4)
Recoveries on loans previously charged-off	2	1	4	3
Net loan recoveries (charge-offs)	0	0	0	(1)
Provision for loan losses	(2)	2	(7)	(6)
Allowance for Loan and Lease Losses, Foreign Currency Translation	0	0
Balance at end of period	37	44	37	44
As a percentage of total loans					0.86%		1.00%
Allowance for loan losses individually evaluated for impairment					$ 0		$ 0
Allowance for loan losses collectively evaluated for impairment					37		44
Total allowance for loan losses	$ 39	$ 42	$ 44	$ 51	37	$ 44	44
Loans individually evaluated for impairment					34		34
Loans collectively evaluated for impairment					4,323		4,349
Total loans					$ 4,357		$ 4,383

Credit Quality And Allowance _8

Credit Quality And Allowance For Credit Losses (Changes In The Allowance For Credit Losses On Lending-Related Commitments) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
Provision for credit losses	$ (35)	$ 0	$ (66)	$ 17
Lending-related commitments
Financing Receivable, Allowance for Credit Loss [Line Items]
Balance at beginning of period	31	34	30	42
Provision for credit losses	(2)	(1)	(1)	(9)
Balance at end of period	$ 29	$ 33	$ 29	$ 33

Credit Quality And Allowance _9

Credit Quality And Allowance For Credit Losses (Individually Evaluated Impaired Loans) (Details) - USD ($) $ in Millions		Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		$ 80	$ 121
Recorded investment in impaired loans with related allowance		163	155
Recorded investment total impaired loans		243	276
Unpaid principal balance		364	346
Related allowance for loan losses		34	27
Business loans | Commercial borrower
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		54	93
Recorded investment in impaired loans with related allowance		155	147
Recorded investment total impaired loans		209	240
Unpaid principal balance		327	307
Related allowance for loan losses		34	27
Business loans | Commercial borrower | Domestic loans
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		12	50
Recorded investment in impaired loans with related allowance		143	130
Recorded investment total impaired loans		155	180
Unpaid principal balance		253	227
Related allowance for loan losses		32	24
Business loans | Commercial borrower | International loans
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		2	2
Recorded investment in impaired loans with related allowance		1	1
Recorded investment total impaired loans		3	3
Unpaid principal balance		9	8
Related allowance for loan losses		0	0
Business loans | Commercial mortgage | Commercial borrower | Domestic loans
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		40	41
Recorded investment in impaired loans with related allowance		11	16
Recorded investment total impaired loans		51	57
Unpaid principal balance		65	72
Related allowance for loan losses		2	3
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance	[1]	39	39
Recorded investment in impaired loans with related allowance	[1]	0	0
Recorded investment total impaired loans	[1]	39	39
Unpaid principal balance	[1]	49	49
Related allowance for loan losses	[1]	0	0
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance	[2]	1	2
Recorded investment in impaired loans with related allowance	[2]	11	16
Recorded investment total impaired loans	[2]	12	18
Unpaid principal balance	[2]	16	23
Related allowance for loan losses	[2]	2	3
Retail loans
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance	[3]	26	28
Recorded investment in impaired loans with related allowance	[3]	8	8
Recorded investment total impaired loans	[3]	34	36
Unpaid principal balance	[3]	37	39
Related allowance for loan losses	[3]	0	0
Retail loans | Consumer borrower
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		9	12
Recorded investment in impaired loans with related allowance		0	0
Recorded investment total impaired loans		9	12
Unpaid principal balance		10	14
Related allowance for loan losses		0	0
Retail loans | Residential mortgage
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		17	16
Recorded investment in impaired loans with related allowance		8	8
Recorded investment total impaired loans		25	24
Unpaid principal balance		27	25
Related allowance for loan losses		0	0
Retail loans | Home equity | Consumer borrower
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		9	11
Recorded investment in impaired loans with related allowance		0	0
Recorded investment total impaired loans		9	11
Unpaid principal balance		10	13
Related allowance for loan losses		0	0
Retail loans | Other consumer | Consumer borrower
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		0	1
Recorded investment in impaired loans with related allowance		0	0
Recorded investment total impaired loans		0	1
Unpaid principal balance		0	1
Related allowance for loan losses		$ 0	$ 0
[1]	Primarily loans to real estate developers
[2]	Primarily loans secured by owner-occupied real estate.
[3]	Individually evaluated retail loans generally have no related allowance for loan losses, primarily due to policy which results in direct write-downs of most restructured retail loans.

Credit Quality And Allowance_10

Credit Quality And Allowance For Credit Losses (Average Individually Evaluated Impaired Loans And Related Interest Recognized) (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		$ 241	$ 322	$ 249	$ 383
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		3	3	6	7
Business loans | Commercial borrower
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		208	290	215	351
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		2	3	5	7
Business loans | Commercial borrower | Domestic loans
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		152	221	157	282
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		0	2	2	4
Business loans | Commercial borrower | International loans
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		3	5	3	5
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		0	0	0	0
Business loans | Commercial mortgage | Commercial borrower | Domestic loans
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		52	64	54	64
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		2	1	3	3
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period	[1]	39	40	39	40
Individually Evaluated Impaired Loans Interest Income Recognized for the Period	[1]	1	1	2	3
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period	[2]	13	24	15	24
Individually Evaluated Impaired Loans Interest Income Recognized for the Period	[2]	1	0	1	0
Retail loans
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		33	32	34	32
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		1	0	1	0
Retail loans | Consumer borrower
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		9	12	10	12
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		0	0	0	0
Retail loans | Residential mortgage
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		24	20	24	20
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		1	0	1	0
Retail loans | Home equity | Consumer borrower
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		9	11	9	11
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		0	0	0	0
Retail loans | Other consumer | Consumer borrower
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		0	1	1	1
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		0	0	0	0
Business Loans | Lease financing | Commercial borrower | Domestic loans
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		1	0	1	0
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		$ 0	$ 0	$ 0	$ 0
[1]	Primarily loans to real estate developers.
[2]	Primarily loans secured by owner-occupied real estate.

Credit Quality And Allowance_11

Credit Quality And Allowance For Credit Losses (Troubled Debt Restructurings By Type Of Modification) (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period		$ 11	$ 5	$ 20	$ 39
Business loans | Commercial borrower
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period		11	3	19	36
Business loans | Commercial borrower | Domestic loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period		11	1	19	32
Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[1]	0	1	0	3
Business loans | Commercial mortgage | Commercial borrower | International loans | Other business lines
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period		0	1	0	1
Retail loans | Home equity | Consumer borrower
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[2]	0	2	1	3
Principal Deferrals
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[3]	11	3	$ 19	$ 36
Minimum period loan terms were extended				90 days	90 days
Principal Deferrals | Business loans | Commercial borrower
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[3]	11	3	$ 19	$ 36
Principal Deferrals | Business loans | Commercial borrower | Domestic loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[3]	11	1	19	32
Principal Deferrals | Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[1],[3]	0	1	0	3
Principal Deferrals | Business loans | Commercial mortgage | Commercial borrower | International loans | Other business lines
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[3]	0	1	0	1
Principal Deferrals | Retail loans | Home equity | Consumer borrower
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[2],[3]	0	0	0	0
Interest Rate Reductions
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period		0	2	1	3
Interest Rate Reductions | Business loans | Commercial borrower
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period		0	0	0	0
Interest Rate Reductions | Business loans | Commercial borrower | Domestic loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period		0	0	0	0
Interest Rate Reductions | Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[1]	0	0	0	0
Interest Rate Reductions | Business loans | Commercial mortgage | Commercial borrower | International loans | Other business lines
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period		0	0	0	0
Interest Rate Reductions | Retail loans | Home equity | Consumer borrower
Financing Receivable, Troubled Debt Restructuring [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[2]	$ 0	$ 2	$ 1	$ 3
[1]	Primarily loans secured by owner-occupied real estate.
[2]	Includes bankruptcy loans for which the court has discharged the borrower's obligation and the borrower has not reaffirmed the debt.
[3]	Primarily represents loan balances where terms were extended 90

Credit Quality And Allowance_12

Credit Quality And Allowance For Credit Losses Credit Quality And Allowance For Credit Losses (Troubled Debt Restructuring Subsequent Default) (Details) - USD ($) $ in Millions		Sep. 30, 2019	Sep. 30, 2018
Principal Deferrals
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance		$ 19	$ 64
Principal Deferrals | Business loans | Commercial borrower
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance		19	63
Principal Deferrals | Business loans | Commercial borrower | Domestic loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance		19	59
Principal Deferrals | Business loans | Commercial mortgage | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	[1]	0	3
Principal Deferrals | Business loans | Business Loans | Commercial borrower | Domestic loans | Commercial Real Estate business line
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance		0	1
Principal Deferrals | Retail loans | Home equity | Consumer borrower | Domestic loans | Commercial Real Estate business line
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance	[2]	0	1
Interest Rate Reductions
Financing Receivable, Troubled Debt Restructuring [Line Items]
Balance		$ 1	$ 3
[1]	Primarily loans secured by owner-occupied real estate.
[2]	Includes bankruptcy loans for which the court has discharged the borrower's obligation and the borrower has not reaffirmed the debt.

Derivative And Credit-Related_3

Derivative And Credit-Related Financial Instruments (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair value of securities pledged as collateral for derivative liabilities	$ 1		$ 1
Cash received as collateral for derivative assets	102		102
Fair value of securities pledged as collateral for derivative assets	27		27
Cash posted as collateral for derivative liabilities	13		13
Aggregate fair value of all derivative instruments with credit-risk contingent features that were in a liability position	0		0
Net gain on open foreign currency positions	0	$ 0	0	$ 0
Allowance for credit losses on lending-related commitments	29		29		$ 30
Allowance for credit losses on lending-related commitments, amount related to unused commitments to extend credit	23		$ 23		24
Final year of expiration for outstanding letters of credit			2028
Risk participation agreements covering standby and commercial letters of credit	164		$ 164		136
Standby and commercial letters of credit	3,300		3,300		3,300
Carrying value of standby and commercial letters of credit included in accrued expenses and other liabilities	33		33		34
Deferred fees on standby and commercial letters of credit included in accrued expenses and other liabilities	27		27		28
Allowance for credit losses on lending-related commitments, amount related to standby and commercial letters of credit	6		6		6
Notional amount of derivative credit risk participation agreements	744		744		703
Maximum estimated exposure to credit risk participation agreements assuming 100% default	$ 26		$ 26		$ 7
Weighted average remaining maturity of credit risk participation agreements, in years			3 years 4 months 24 days

Derivative And Credit-Related_4

Derivative And Credit-Related Financial Instruments (Schedule Of Derivative Instruments) (Details) - USD ($) $ in Millions		Sep. 30, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	$ 29,089	$ 21,557
Fair Value of Gross Derivative Assets		448	275
Fair Value of Gross Derivative Liabilities		209	269
Derivative assets, Netting adjustment - Offsetting derivative liabilities		(45)	(45)
Derivative liabilities, Netting adjustment - Offsetting derivative assets		(45)	(45)
Derivative assets, Netting adjustment - Cash collateral received		(101)	(174)
Derivative liabilities, Netting adjustment, Cash collateral posted		(12)	(1)
Net derivative assets included in the consolidated balance sheets	[2]	302	56
Net derivative liabilities included in the consolidated balance sheets	[2]	152	223
Derivative asset, securities pledged as collateral		(1)	(1)
Derivative liability, securities pledged as collateral		(26)	0
Net derivative assets after deducting amounts not offset in the consolidated balance sheets		301	55
Net derivative liabilities after deducting amounts not offset in the consolidated balance sheets		126	223
Credit valuation adjustments for counterparty credit risk		12	2
Risk management purposes
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	7,434	2,927
Fair Value of Gross Derivative Assets		1	1
Fair Value of Gross Derivative Liabilities		0	3
Risk management purposes | Derivatives designated as hedging instruments | Fair Value Hedging | Interest rate swap
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	3,325	2,625
Fair Value of Gross Derivative Assets		0	0
Fair Value of Gross Derivative Liabilities		0	2
Risk management purposes | Derivatives designated as hedging instruments | Swaps - cash flow - receive fixed/pay floating rate | Interest rate swap
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	3,800	0
Fair Value of Gross Derivative Assets		0	0
Fair Value of Gross Derivative Liabilities		0	0
Risk management purposes | Derivatives used as economic hedges | Foreign exchange spot, forwards and swaps
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	309	302
Fair Value of Gross Derivative Assets		1	1
Fair Value of Gross Derivative Liabilities		0	1
Customer-initiated and other activities
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	21,655	18,630
Fair Value of Gross Derivative Assets		447	274
Fair Value of Gross Derivative Liabilities		209	266
Customer-initiated and other activities | Interest rate contracts
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	17,511	14,885
Fair Value of Gross Derivative Assets		275	67
Fair Value of Gross Derivative Liabilities		43	68
Customer-initiated and other activities | Interest rate caps and floors written
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	912	885
Fair Value of Gross Derivative Assets		0	0
Fair Value of Gross Derivative Liabilities		1	1
Customer-initiated and other activities | Interest rate caps and floors purchased
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	912	885
Fair Value of Gross Derivative Assets		1	1
Fair Value of Gross Derivative Liabilities		0	0
Customer-initiated and other activities | Interest rate swap
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	15,687	13,115
Fair Value of Gross Derivative Assets		274	66
Fair Value of Gross Derivative Liabilities		42	67
Customer-initiated and other activities | Energy contracts
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	3,083	2,650
Fair Value of Gross Derivative Assets		160	189
Fair Value of Gross Derivative Liabilities		156	186
Customer-initiated and other activities | Energy caps and floors written
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	468	278
Fair Value of Gross Derivative Assets		0	0
Fair Value of Gross Derivative Liabilities		30	26
Customer-initiated and other activities | Energy caps and floors purchased
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	468	278
Fair Value of Gross Derivative Assets		30	26
Fair Value of Gross Derivative Liabilities		0	0
Customer-initiated and other activities | Energy swaps
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	2,147	2,094
Fair Value of Gross Derivative Assets		130	163
Fair Value of Gross Derivative Liabilities		126	160
Customer-initiated and other activities | Foreign exchange spot, options and swaps
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	1,061	1,095
Fair Value of Gross Derivative Assets		12	18
Fair Value of Gross Derivative Liabilities		$ 10	$ 12
[1]	Notional or contractual amounts, which represent the extent of involvement in the derivatives market, are used to determine the contractual cash flows required in accordance with the terms of the agreement. These amounts are typically not exchanged, significantly exceed amounts subject to credit or market risk and are not reflected in the Consolidated Balance Sheets.
[2]	Net derivative assets are included in accrued income and other assets and net derivative liabilities are included in accrued expenses and other liabilities on the Consolidated Balance Sheets. Included in the fair value of net derivative assets and net derivative liabilities are credit valuation adjustments reflecting counterparty credit risk and credit risk of the Corporation. The fair value of net derivative assets included credit valuation adjustments for counterparty credit risk of $12 million and $2 million at September 30, 2019 and December 31, 2018 , respectively.

Derivative And Credit-Related_5

Derivative And Credit-Related Financial Instruments Derivative and Credit-Related Financial Instruments (Schedule of the Effects of Fair Value Hedging on the Consolidated Statements of Comprehensive Income (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Total interest on medium- and long-term debt	[1]	$ 50	$ 40	$ 152	$ 97
Swaps - fair value - receive fixed/pay floating | Risk management purposes | Interest rate swap
Interest rate contract: Hedge items interest expense		28	21	80	51
Interest rate contracts: Derivatives designated as hedging instruments net interest income		$ (2)	$ (1)	$ (1)	$ (7)
[1]	Includes the effects of hedging.

Derivative And Credit-Related_6

Derivative And Credit-Related Financial Instruments (Schedule Of Weighted Average Maturity And Interest Rates On Risk Management Interest Rate Swaps) (Details) - USD ($) $ in Millions		9 Months Ended	12 Months Ended
		Sep. 30, 2019	Dec. 31, 2018
Notional Amount	[1]	$ 29,089	$ 21,557
Cumulative hedging adjustments		189	49
Cumulative hedging adjustments on discontinued hedging relationship		7	8
Risk management purposes
Notional Amount	[1]	7,434	2,927
Variable rate loans | Swaps - cash flow - receive fixed/pay floating rate | Risk management purposes | Cash flow swap
Notional Amount		3,800
Carrying Value of Hedged Item
Weighted Average Remaining Maturity		3 years 1 month 6 days
Weighted Average Receive Rate		2.04%
Weighted Average Pay Rate	[2]	2.07%
Medium- and long-term debt | Swaps - fair value - receive fixed/pay floating | Risk management purposes | Interest rate swap
Notional Amount		$ 3,325	2,625
Carrying Value of Hedged Item	[3]	$ 3,511	$ 2,663
Weighted Average Remaining Maturity		4 years 8 months 12 days	3 years 10 months 24 days
Weighted Average Receive Rate		3.44%	3.40%
Weighted Average Pay Rate	[2]	3.09%	3.45%
[1]	Notional or contractual amounts, which represent the extent of involvement in the derivatives market, are used to determine the contractual cash flows required in accordance with the terms of the agreement. These amounts are typically not exchanged, significantly exceed amounts subject to credit or market risk and are not reflected in the Consolidated Balance Sheets.
[2]	Variable rates paid on receive fixed swaps designated as fair value and cash flow hedges are based on one- and six-month LIBOR rates in effect at September 30, 2019 and December 31, 2018 .
[3]	Included $ 189 million and $ 49 million of cumulative hedging adjustments to fair value hedges at September 30, 2019 and December 31, 2018 , respectively, which included $ 7 million and $ 8 million

Derivative And Credit-Related_7

Derivative And Credit-Related Financial Instruments (Schedule Of Net Gains Recognized In Income On Customer-Initiated Derivatives) (Details) - Customer-initiated and other activities - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Net derivative gain recognized in income	$ 16	$ 21	$ 53	$ 56
Interest rate contracts | Other noninterest income
Derivative Instruments, Gain (Loss) [Line Items]
Net derivative gain recognized in income	4	9	16	20
Energy contracts | Other noninterest income
Derivative Instruments, Gain (Loss) [Line Items]
Net derivative gain recognized in income	1	1	4	1
Foreign exchange contracts | Foreign exchange income
Derivative Instruments, Gain (Loss) [Line Items]
Net derivative gain recognized in income	$ 11	$ 11	$ 33	$ 35

Derivative And Credit-Related_8

Derivative And Credit-Related Financial Instruments (Schedule Of Financial Instruments With Off-Balance Sheet Credit Risk) (Details) - Maximum - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Unused Commitments to Extend Credit
Loss contingency, estimate of possible loss, maximum	$ (26,436)	$ (27,267)
Commercial And Other | Unused Commitments to Extend Credit
Loss contingency, estimate of possible loss, maximum	(23,280)	(24,266)
Bankcard, Revolving Check Credit And Home Equity Loan Commitments | Unused Commitments to Extend Credit
Loss contingency, estimate of possible loss, maximum	(3,156)	(3,001)
Standby Letters Of Credit
Loss contingency, estimate of possible loss, maximum	(3,281)	(3,244)
Commercial Letters Of Credit
Loss contingency, estimate of possible loss, maximum	$ (17)	$ (39)

Derivative And Credit-Related_9

Derivative And Credit-Related Financial Instruments (Summary Of Internally Classified Watch List Letters Of Credit) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Total criticized standby and commercial letters of credit	$ 45	$ 49
As a percentage of total outstanding standby and commercial letters of credit	1.40%	1.50%

Variable Interest Entities (V_3

Variable Interest Entities (VIEs) (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Variable Interest Entity
Unfunded commitments to fund tax credit entities	$ 173
Amount of financial or other support not contractually required provided by the Corporation to VIEs	0	$ 0
Low Income Housing Tax Credit Entities
Variable Interest Entity
Exposure to loss as a result of involvement with VIEs	446
Other Tax Credit Entities
Variable Interest Entity
Exposure to loss as a result of involvement with VIEs	$ 6

Variable Interest Entities (V_4

Variable Interest Entities (VIEs) (Impact Of VIEs On The Consolidated Statements Of Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Variable Interest Entity
Other noninterest income	$ 23	$ 29	$ 70	$ 73
Provision for income taxes	80	63	252	210
Variable Interest Entity
Variable Interest Entity
Other noninterest income	0	0	1	2
Provision for income taxes	(3)	(3)	(8)	(9)
Variable Interest Entity | Low income housing tax credits
Variable Interest Entity
Provision for income taxes, amortization of LIHTC investments	16	17	48	48
Provision for income taxes, affordable housing tax credits and other tax benefits	(16)	(16)	(46)	(46)
Variable Interest Entity | Other tax benefits related to tax credit entities
Variable Interest Entity
Provision for income taxes, affordable housing tax credits and other tax benefits	$ (3)	$ (4)	$ (10)	$ (11)

Medium- And Long-Term Debt (Nar

Medium- And Long-Term Debt (Narrative) (Details) - USD ($) $ in Millions		Sep. 30, 2019		Aug. 01, 2019	Jul. 23, 2019	Feb. 01, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Unamortized debt issuance cost		$ 13					$ 8
Parent Company [Member]
Debt Instrument [Line Items]
Other Long-term Debt		1,495					1,209
Subsidiaries
Debt Instrument [Line Items]
Other Long-term Debt		1,175					663
Long-term Federal Home Loan Bank Advances		3,800					3,800
Real estate-related loans securing FHLB advances		17,200
Potential FHLB borrowing capacity		5,100
Floating-rate based on FHLB auction rate due 2026 | Subsidiaries
Debt Instrument [Line Items]
Long-term Federal Home Loan Bank Advances		$ 2,800					2,800
Weighted-average interest rate		2.16%
Floating-rate based on FHLB auction rate due 2028 | Subsidiaries
Debt Instrument [Line Items]
Long-term Federal Home Loan Bank Advances		$ 1,000					$ 1,000
Weighted-average interest rate		2.34%
4.00% subordinated notes due 2025 | Subsidiaries
Debt Instrument [Line Items]
Stated interest rate		4.00%					4.00%
4.00% Notes Due 2029 | Parent Company [Member]
Debt Instrument [Line Items]
Other Long-term Debt		$ 603	[1]	$ 200		$ 350	$ 0	[1]
Stated interest rate		4.00%				4.00%
2.50% notes due 2024 | Subsidiaries
Debt Instrument [Line Items]
Other Long-term Debt	[1]	$ 503			$ 500		$ 0
Stated interest rate		2.50%			2.50%
[1]	The fixed interest rates on these notes have been swapped to a variable rate and designated in a hedging relationship. Accordingly, carrying value has been adjusted to reflect the change in the fair value of the debt as a result of changes in the benchmark rate.

Medium- And Long-Term Debt (Sch

Medium- And Long-Term Debt (Schedule Of Medium- And Long-Term Debt) (Details) - USD ($) $ in Millions		9 Months Ended		12 Months Ended
		Sep. 30, 2019		Dec. 31, 2018		Aug. 01, 2019	Jul. 23, 2019	Feb. 01, 2019
Debt Instrument [Line Items]
Total medium- and long-term debt		$ 7,311		$ 6,463
Parent Company
Debt Instrument [Line Items]
Medium-term notes		1,495		1,209
Total medium- and long-term debt		1,764		1,459
Subsidiaries
Debt Instrument [Line Items]
Subordinated notes		572		541
Medium-term notes		1,175		663
Long-term Federal Home Loan Bank Advances		3,800		3,800
Total medium- and long-term debt		5,547		5,004
3.80% subordinated notes due 2026 | Parent Company
Debt Instrument [Line Items]
Subordinated notes	[1]	$ 269		$ 250
Stated interest rate		3.80%		3.80%
Maturity date		Jul. 22, 2026		Jul. 22, 2026
2.125% notes due 2019 | Parent Company
Debt Instrument [Line Items]
Medium-term notes	[1]	$ 0		$ 348
Stated interest rate		2.125%		2.125%
Maturity date		May 23, 2019		May 23, 2019
3.70% Notes Due 2023 | Parent Company
Debt Instrument [Line Items]
Medium-term notes	[1]	$ 892		$ 861
Stated interest rate		3.70%		3.70%
Maturity date		Jul. 31, 2023		Jul. 31, 2023
4.00% Notes Due 2029 | Parent Company
Debt Instrument [Line Items]
Medium-term notes		$ 603	[1]	$ 0	[1]	$ 200		$ 350
Stated interest rate		4.00%						4.00%
Maturity date		Feb. 1, 2029
4.00% subordinated notes due 2025 | Subsidiaries
Debt Instrument [Line Items]
Subordinated notes	[1]	$ 365		$ 343
Stated interest rate		4.00%		4.00%
Maturity date		Jul. 27, 2025		Jul. 27, 2025
7.875% subordinated notes due 2026 | Subsidiaries
Debt Instrument [Line Items]
Subordinated notes	[1]	$ 207		$ 198
Stated interest rate		7.875%		7.875%
Maturity date		Sep. 15, 2026		Sep. 15, 2026
2.50% notes due 2020 | Subsidiaries
Debt Instrument [Line Items]
Medium-term notes	[1]	$ 672		$ 663
Stated interest rate		2.50%		2.50%
Maturity date		Jun. 2, 2020		Jun. 2, 2020
2.50% notes due 2024 | Subsidiaries
Debt Instrument [Line Items]
Medium-term notes	[1]	$ 503		$ 0			$ 500
Stated interest rate		2.50%					2.50%
Floating-rate based on FHLB auction rate due 2026 | Subsidiaries
Debt Instrument [Line Items]
Long-term Federal Home Loan Bank Advances		$ 2,800		2,800
Weighted-average interest rate		2.16%
Floating-rate based on FHLB auction rate due 2026 | Subsidiaries | Maximum
Debt Instrument [Line Items]
Maturity date		May 20, 2026
Floating-rate based on FHLB auction rate due 2026 | Subsidiaries | Minimum
Debt Instrument [Line Items]
Maturity date		Mar. 4, 2026
Floating-rate based on FHLB auction rate due 2028 | Subsidiaries
Debt Instrument [Line Items]
Long-term Federal Home Loan Bank Advances		$ 1,000		$ 1,000
Maturity date		Jan. 26, 2028
Weighted-average interest rate		2.34%
[1]	The fixed interest rates on these notes have been swapped to a variable rate and designated in a hedging relationship. Accordingly, carrying value has been adjusted to reflect the change in the fair value of the debt as a result of changes in the benchmark rate.

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Loss (Schedule Of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Millions		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Investment securities, Balance at beginning of period, net of tax		$ (138)	$ (101)
Cumulative effect of change in accounting principle		0	1
Investment securities, Net unrealized holding (losses) gains arising during the period		267	(254)
Investment securities, Less: (Benefit) provision for income taxes		62	(59)
Investment securities, Net unrealized holding (losses) gains arising during the period, net of tax		205	(195)
Investment securities, Net realized (losses) gains included in net securities (losses) gains		(8)	(20)
Investment securities, Less: Benefit for income taxes		(2)	(5)
Investment Securities, Reclassification adjustment for net securities (losses) gains included in net income, net of tax		(6)	(15)
Investment securities, Reclassification adjustment for net securities (losses) gains included in net income, net of tax		211	(180)
Investment securities, Balance at end of period, net of tax		73	(280)
Cash flow hedges, Balance at beginning of period, net of tax		0	0
Cash flow hedge: Net gains arising during the period		69	0
Cash flow hedges, Less: Provision for income tax		16	0
Change in net cash flow hedge gains arising during the period, net of tax		53	0
Net cash flow hedge losses included in interest and fees on loans		(1)	0
Cash flows hedges, Change in net gain on cash flow hedges		54	0
Cash flow hedges, Balance at end of period, net of tax	[1]	54	0
Benefit plans, Balance at beginning of period, net of tax		(471)	(350)
Benefit plans, Amortization of actuarial net loss		30	45
Benefit plans, Amortization of prior service credit		(20)	(20)
Benefit plans, Amounts recognized in other noninterest expense		10	25
Benefit plans, Less: Provision for income taxes		2	6
Benefit plans, Change in defined benefit pension and other postretirement plans adjustment, net of tax		8	19
Benefit plans, Balance at end of period, net of tax		(463)	(331)
Total accumulated other comprehensive loss at end of period, net of tax		$ (336)	$ (611)	$ (609)
[1]	The Corporation expects to reclassify $12 million of net gains, net of tax, from accumulated other comprehensive loss to earnings over the next twelve months if interest yield curves and notional amounts remain at September 30, 2019 levels.

Net Income Per Share (Basic And

Net Income Per Share (Basic And Diluted Net Income Per Share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Earnings Per Share [Abstract]
Net income	$ 292	$ 318	$ 929	$ 925
Income allocated to participating securities	2	2	5	6
Net income attributable to shares	$ 290	$ 316	$ 924	$ 919
Basic average shares	147	167	152	170
Basic net income per share	$ 1.98	$ 1.89	$ 6.08	$ 5.41
Basic average shares	147	167	152	170
Net effect of the assumed exercise of stock options	1	2	2	2
Net effect of the assumed exercise of warrants	0	1	0	1
Diluted average shares	148	170	154	173
Diluted net income per share	$ 1.96	$ 1.86	$ 6.02	$ 5.32

Net Income Per Share (Schedule

Net Income Per Share (Schedule of Average Shares Excluded From Diluted Net Income Per Share Computation) (Details) - Stock Options - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Average outstanding options	814,044	0	570,433	0
Minimum
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Range of exercise prices	$ 67.53	$ 0	$ 67.53	$ 0
Maximum
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Range of exercise prices	$ 95.25	$ 0	$ 95.25	$ 0

Employee Benefit Plans Employee

Employee Benefit Plans Employee Benefit Plans (Net Periodic Defined Benefit Cost) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Defined Benefit Plan Disclosure [Line Items]
Net periodic defined benefit (credit) cost	$ (9)	$ (4)	$ (23)	$ (14)
Qualified Defined Benefit Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Total other components of net benefit (credit) cost	(18)	(14)	(53)	(43)
Net periodic defined benefit (credit) cost	(10)	(7)	(30)	(21)
Qualified Defined Benefit Pension Plan | Component recognized in salaries and benefits expense
Defined Benefit Plan Disclosure [Line Items]
Service cost	8	7	23	22
Qualified Defined Benefit Pension Plan | Component recognized in noninterest expense
Defined Benefit Plan Disclosure [Line Items]
Interest Cost	20	19	60	56
Expected return on plan assets	(41)	(41)	(124)	(123)
Amortization of prior service credit	(5)	(5)	(14)	(14)
Amortization of net loss	8	13	25	38
Non-Qualified Defined Benefit Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Total other components of net benefit (credit) cost	2	3	6	7
Net periodic defined benefit (credit) cost	2	3	8	8
Non-Qualified Defined Benefit Pension Plan | Component recognized in salaries and benefits expense
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	2	1
Non-Qualified Defined Benefit Pension Plan | Component recognized in noninterest expense
Defined Benefit Plan Disclosure [Line Items]
Interest Cost	3	2	7	6
Amortization of prior service credit	(2)	(1)	(6)	(6)
Amortization of net loss	1	2	5	7
Postretirement Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Net periodic defined benefit (credit) cost	(1)	0	(1)	(1)
Postretirement Benefit Plan | Component recognized in noninterest expense
Defined Benefit Plan Disclosure [Line Items]
Interest Cost	0	0	1	1
Expected return on plan assets	$ (1)	$ 0	$ (2)	$ (2)

Income Taxes And Tax-Related _2

Income Taxes And Tax-Related Items Income Taxes And Tax-Related Items (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Unrecognized tax benefits	$ 16	$ 14
Reasonably possible decrease in unrecognized tax benefits in next 12 months	1
Tax-related interest and penalties payable	8	7
Net deferred tax assets	92	166
Decrease in net deferred tax assets	74
State net operating loss carryforwards	4	4
Valuation allowance for deferred tax assets	$ 3	$ 3
Minimum
Years state net operating loss carryforwards expire	Dec. 31, 2019
Maximum
Years state net operating loss carryforwards expire	Dec. 31, 2028

Contingent Liabilities (Narrati

Contingent Liabilities (Narrative) (Details) - USD ($) $ in Millions	Jan. 17, 2014	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Loss Contingencies [Line Items]
Legal fees		$ 5	$ 4	$ 10	$ 11
Pending Litigation | Minimum
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss		0		0
Pending Litigation | Maximum
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss		$ 35		$ 35
Butte Local Development v. Masters Group v. Comerica Bank
Loss Contingencies [Line Items]
Amount of damages awarded by the jury	$ 52

Business Segment Information (N

Business Segment Information (Narrative) (Details)	9 Months Ended
	Sep. 30, 2019segmentsmarkets
Segment Reporting [Abstract]
Number of Major Business Segments | segments	3
Number of Primary Market Segments | markets	3

Business Segment Information (B

Business Segment Information (Business Segment Financial Results) (Details) - USD ($) $ in Millions		3 Months Ended				9 Months Ended
		Sep. 30, 2019		Sep. 30, 2018		Sep. 30, 2019		Sep. 30, 2018
Net interest income (expense)		$ 586		$ 599		$ 1,795		$ 1,738
Provision for credit losses		35		0		66		(17)
Noninterest income		256		234		744		726
Noninterest expenses		435		452		1,292		1,346
Provision (benefit) for income taxes		80		63		252		210
Net income (loss)		292		318		929		925
Net credit-related charge-offs (recoveries)		42		15		86		40
Assets, average		71,736		71,210		70,927		70,689
Loans, average		50,887		48,584		50,514		48,744
Deposits, average		$ 55,716		$ 56,093		$ 54,909		$ 56,004
Return on average assets	[1]	1.61%		1.77%		1.75%		1.75%
Efficiency ratio	[2]	51.54%		52.93%		50.66%		54.12%
Discrete tax benefits		$ 5		$ (23)		$ 16		$ 48
Business Bank
Net interest income (expense)		420		414		1,252		1,200
Provision for credit losses		39		0		85		(9)
Noninterest income		140		137		412		403
Noninterest expenses		199		211		592		635
Provision (benefit) for income taxes		74		76		227		222
Net income (loss)		248		264		760		755
Net credit-related charge-offs (recoveries)		43		14		90		40
Assets, average		45,459		43,165		44,902		43,205
Loans, average		43,889		41,591		43,456		41,580
Deposits, average		$ 28,917		$ 30,286		$ 28,545		$ 30,168
Return on average assets	[1]	2.17%		2.43%		2.26%		2.34%
Efficiency ratio	[2]	35.62%		38.24%		35.61%		39.59%
Retail Bank
Net interest income (expense)		$ 142		$ 140		$ 434		$ 402
Provision for credit losses		(2)		1		(5)		(2)
Noninterest income		31		35		95		100
Noninterest expenses		149		153		441		450
Provision (benefit) for income taxes		5		5		21		12
Net income (loss)		21		16		72		42
Net credit-related charge-offs (recoveries)		1		0		1		0
Assets, average		2,871		2,621		2,841		2,629
Loans, average		2,114		2,057		2,108		2,062
Deposits, average		$ 20,761		$ 20,765		$ 20,628		$ 20,888
Return on average assets	[1]	0.39%		0.31%		0.46%		0.26%
Efficiency ratio	[2]	84.54%		86.96%		82.70%		89.03%
Wealth Management
Net interest income (expense)		$ 47		$ 46		$ 140		$ 133
Provision for credit losses		(3)		1		(13)		(2)
Noninterest income		69		66		201		201
Noninterest expenses		69		72		208		218
Provision (benefit) for income taxes		12		10		35		29
Net income (loss)		38		29		111		89
Net credit-related charge-offs (recoveries)		(2)		1		(5)		0
Assets, average		5,032		5,068		5,092		5,233
Loans, average		4,884		4,936		4,950		5,102
Deposits, average		$ 3,775		$ 3,988		$ 3,772		$ 3,879
Return on average assets	[1]	3.01%		2.28%		2.92%		2.26%
Efficiency ratio	[2]	59.79%		63.93%		61.04%		65.51%
Finance
Net interest income (expense)		$ (38)		$ (16)		$ (77)		$ (37)
Provision for credit losses		0		0		0		0
Noninterest income		12		(7)		30		16
Noninterest expenses		(1)		(1)		(1)		(3)
Provision (benefit) for income taxes		(8)		(8)		(16)		(13)
Net income (loss)		(17)		(14)		(30)		(5)
Net credit-related charge-offs (recoveries)		0		0		0		0
Assets, average		14,392		13,696		14,184		13,736
Loans, average		0		0		0		0
Deposits, average		2,049		929		1,788		949
Other
Net interest income (expense)		15		15		46		40
Provision for credit losses		1		(2)		(1)		(4)
Noninterest income		4		3		6		6
Noninterest expenses		19		17		52		46
Provision (benefit) for income taxes		(3)	[3]	(20)	[3]	(15)	[4]	(40)	[4]
Net income (loss)		2		23		16		44
Net credit-related charge-offs (recoveries)		0		0		0		0
Assets, average		3,982		6,660		3,908		5,886
Loans, average		0		0		0		0
Deposits, average		$ 214		$ 125		$ 176		$ 120
[1]	Return on average assets is calculated based on the greater of average assets or average liabilities and attributed equity.
[2]	Noninterest expenses as a percentage of the sum of net interest income and noninterest income excluding net gains (losses) from securities and a derivative contract tied to the conversion rate of Visa Class B shares.
[3]	Included discrete tax benefits of $5 million and $23 million for the three months ended September 30, 2019 and 2018 , respectively.
[4]	Included discrete tax benefits of $16 million and $48 million for the nine months ended September 30, 2019 and 2018 , respectively.

Business Segment Information (M

Business Segment Information (Market Segment Financial Results) (Details) - USD ($) $ in Millions		3 Months Ended				9 Months Ended
		Sep. 30, 2019		Sep. 30, 2018		Sep. 30, 2019		Sep. 30, 2018
Net interest income (expense)		$ 586		$ 599		$ 1,795		$ 1,738
Provision for credit losses		35		0		66		(17)
Noninterest income		256		234		744		726
Noninterest expenses		435		452		1,292		1,346
Provision (benefit) for income taxes		80		63		252		210
Net income (loss)		292		318		929		925
Net credit-related charge-offs (recoveries)		42		15		86		40
Assets, average		71,736		71,210		70,927		70,689
Loans, average		50,887		48,584		50,514		48,744
Deposits, average		$ 55,716		$ 56,093		$ 54,909		$ 56,004
Return on average assets	[1]	1.61%		1.77%		1.75%		1.75%
Efficiency ratio	[2]	51.54%		52.93%		50.66%		54.12%
Discrete tax benefits		$ 5		$ (23)		$ 16		$ 48
Michigan
Net interest income (expense)		185		185		557		540
Provision for credit losses		(1)		4		(6)		38
Noninterest income		74		76		218		222
Noninterest expenses		139		144		412		432
Provision (benefit) for income taxes		27		25		83		67
Net income (loss)		94		88		286		225
Net credit-related charge-offs (recoveries)		6		8		10		7
Assets, average		13,213		13,055		13,176		13,291
Loans, average		12,554		12,424		12,605		12,556
Deposits, average		$ 20,164		$ 20,720		$ 19,959		$ 20,947
Return on average assets	[1]	1.78%		1.63%		1.85%		1.39%
Efficiency ratio	[2]	53.31%		54.96%		53.00%		56.50%
California
Net interest income (expense)		$ 203		$ 200		$ 616		$ 582
Provision for credit losses		(6)		3		(11)		(8)
Noninterest income		41		43		121		124
Noninterest expenses		102		106		301		316
Provision (benefit) for income taxes		37		34		113		101
Net income (loss)		111		100		334		297
Net credit-related charge-offs (recoveries)		5		5		9		18
Assets, average		18,726		18,349		19,000		18,542
Loans, average		18,393		18,074		18,695		18,284
Deposits, average		$ 16,725		$ 16,894		$ 16,433		$ 16,875
Return on average assets	[1]	2.37%		2.18%		2.36%		2.14%
Efficiency ratio	[2]	41.64%		43.10%		40.82%		44.76%
Texas
Net interest income (expense)		$ 125		$ 120		$ 372		$ 353
Provision for credit losses		50		(9)		88		(37)
Noninterest income		31		33		97		94
Noninterest expenses		86		89		255		273
Provision (benefit) for income taxes		5		16		30		48
Net income (loss)		15		57		96		163
Net credit-related charge-offs (recoveries)		34		3		73		11
Assets, average		11,462		10,263		11,240		10,352
Loans, average		10,805		9,694		10,586		9,789
Deposits, average		$ 8,705		$ 8,902		$ 8,690		$ 9,016
Return on average assets	[1]	0.48%		2.18%		1.13%		2.10%
Efficiency ratio	[2]	55.57%		58.06%		54.35%		60.92%
Other Markets
Net interest income (expense)		$ 96		$ 95		$ 281		$ 260
Provision for credit losses		(9)		4		(4)		(6)
Noninterest income		94		86		272		264
Noninterest expenses		90		97		273		282
Provision (benefit) for income taxes		22		16		57		47
Net income (loss)		87		64		227		201
Net credit-related charge-offs (recoveries)		(3)		(1)		(6)		4
Assets, average		9,961		9,187		9,419		8,882
Loans, average		9,135		8,392		8,628		8,115
Deposits, average		$ 7,859		$ 8,523		$ 7,863		$ 8,097
Return on average assets	[1]	3.47%		2.74%		3.23%		3.03%
Efficiency ratio	[2]	47.19%		54.02%		49.33%		53.91%
Finance & Other
Net interest income (expense)		$ (23)		$ (1)		$ (31)		$ 3
Provision for credit losses		1		(2)		(1)		(4)
Noninterest income		16		(4)		36		22
Noninterest expenses		18		16		51		43
Provision (benefit) for income taxes		(11)	[3]	(28)	[3]	(31)	[4]	(53)	[4]
Net income (loss)		(15)		9		(14)		39
Net credit-related charge-offs (recoveries)		0		0		0		0
Assets, average		18,374		20,356		18,092		19,622
Loans, average		0		0		0		0
Deposits, average		$ 2,263		$ 1,054		$ 1,964		$ 1,069
[1]	Return on average assets is calculated based on the greater of average assets or average liabilities and attributed equity.
[2]	Noninterest expenses as a percentage of the sum of net interest income and noninterest income excluding net gains (losses) from securities and a derivative contract tied to the conversion rate of Visa Class B shares.
[3]	Included discrete tax benefits of $5 million and $23 million for the three months ended September 30, 2019 and 2018 , respectively.
[4]	Included discrete tax benefits of $16 million and $48 million for the nine months ended September 30, 2019 and 2018 , respectively.

Revenue from Contracts with C_3

Revenue from Contracts with Customers (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		$ 190	$ 190	$ 563	$ 563
Other sources of noninterest income		66	44	181	163
Total noninterest income		256	234	744	726
Business Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		93	92	278	274
Other sources of noninterest income		47	45	134	129
Total noninterest income		140	137	412	403
Retail Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		30	34	90	95
Other sources of noninterest income		1	1	5	5
Total noninterest income		31	35	95	100
Wealth Management
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		67	64	195	194
Other sources of noninterest income		2	2	6	7
Total noninterest income		69	66	201	201
Finance & Other
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		0	0	0	0
Other sources of noninterest income		16	(4)	36	22
Total noninterest income		16	(4)	36	22
Credit and Debit Card [Member]
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		67	61	195	180
Credit and Debit Card [Member] | Business Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		55	50	162	149
Credit and Debit Card [Member] | Retail Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		11	10	30	28
Credit and Debit Card [Member] | Wealth Management
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		1	1	3	3
Credit and Debit Card [Member] | Finance & Other
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		0	0	0	0
Service charges on deposit accounts
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		51	53	153	160
Service charges on deposit accounts | Business Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		32	34	98	102
Service charges on deposit accounts | Retail Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		18	18	52	54
Service charges on deposit accounts | Wealth Management
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		1	1	3	4
Service charges on deposit accounts | Finance & Other
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		0	0	0	0
Fiduciary income
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		53	51	154	155
Fiduciary income | Business Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		0	0	0	0
Fiduciary income | Retail Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		0	0	0	0
Fiduciary income | Wealth Management
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		53	51	154	155
Fiduciary income | Finance & Other
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		0	0	0	0
Commercial loan servicing fees
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	[1]	5	5	13	14
Commercial loan servicing fees | Business Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	[1]	5	5	13	14
Commercial loan servicing fees | Retail Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	[1]	0	0	0	0
Commercial loan servicing fees | Wealth Management
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	[1]	0	0	0	0
Commercial loan servicing fees | Finance & Other
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	[1]	0	0	0	0
Brokerage Commissions Revenue [Member]
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		7	7	21	20
Brokerage Commissions Revenue [Member] | Business Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		0	0	0	0
Brokerage Commissions Revenue [Member] | Retail Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		0	0	0	0
Brokerage Commissions Revenue [Member] | Wealth Management
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		7	7	21	20
Brokerage Commissions Revenue [Member] | Finance & Other
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers		0	0	0	0
Other noninterest income
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	[2]	7	13	27	34
Other noninterest income | Business Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	[2]	1	3	5	9
Other noninterest income | Retail Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	[2]	1	6	8	13
Other noninterest income | Wealth Management
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	[2]	5	4	14	12
Other noninterest income | Finance & Other
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	[2]	$ 0	$ 0	$ 0	$ 0
[1]	Included in commercial lending fees on the Consolidated Statements of Comprehensive Income.
[2]	Excludes derivative, warrant and other miscellaneous income.

Leases (Narrative) (Details)

Leases (Narrative) (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019USD ($)		Sep. 30, 2019USD ($)
Leases [Abstract]
Operating lease expense	$ 16		$ 47
Variable lease expense	4		11
Lease expense	20		58
Right of use assets	320		320
Operating lease liabilities	$ 358		$ 358
Weighted average lease term for lease liabilities	9 years		9 years
Weighted average discount rate of remaining payments	3.82%		3.82%
New Right of Use Assets			$ 35
Cash paid on operating lease liabilities	$ 17		50
Lease-related revenue	4		10
Sales-type and Direct Financing Leases, Lease Receivable	$ 361	[1]	$ 361	[1]
[1]	Excludes net investment in leveraged leases of $217 million .

Leases (Contractual Maturities

Leases (Contractual Maturities of Operating Lease Liabilities) (Details) $ in Millions	9 Months Ended
	Sep. 30, 2019USD ($)
Leases [Abstract]
2019	$ 10	[1]
2020	64
2021	59
2022	50
2023	44
Thereafter	204
Total contractual maturities	431
Less imputed interest	(73)
Total operating lease liabilities	$ 358
[1]	Contractual maturities for the three months remaining in 2019 .

Leases (Contractual Maturitie_2

Leases (Contractual Maturities of Sales-Type and Direct Financing Lease Receivables) (Details) $ in Millions	Sep. 30, 2019USD ($)
Leases [Abstract]
2019	$ 18
2020	63
2021	52
2022	88
2023	39
Thereafter	58
Total lease payments receivable	318
Unguaranteed residual values	64
Less deferred interest income	(21)
Sales-type and Direct Financing Leases, Lease Receivable	$ 361	[1]
[1]	Excludes net investment in leveraged leases of $217 million .