Comerica (CMA) 10-Q 31 Jul 17 2017 Q2 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2017	Jul. 25, 2017
Document And Entity Information [Abstract]
Document Type	10-Q
Document Period End Date	Jun. 30, 2017
Amendment Flag	false
Entity Registrant Name	Comerica INC /NEW/
Entity Central Index Key	28,412
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q2
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		175,910,900
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions		Jun. 30, 2017	Dec. 31, 2016
ASSETS
Cash and due from banks		$ 1,372	$ 1,249
Interest-bearing deposits with banks		4,259	5,969
Other short-term investments		90	92
Investment securities available-for-sale	[1]	10,944	10,787
Investment securities held-to-maturity		1,430	1,582
Commercial loans		31,449	30,994
Real estate construction loans		2,857	2,869
Commercial mortgage loans		8,974	8,931
Lease financing		472	572
International loans		1,145	1,258
Residential mortgage loans		1,976	1,942
Consumer loans		2,535	2,522
Total loans		49,408	49,088
Less allowance for loan losses		(705)	(730)
Net loans		48,703	48,358
Premises and equipment		484	501
Accrued income and other assets		4,165	4,440
Total assets		71,447	72,978
LIABILITIES AND SHAREHOLDERS' EQUITY
Noninterest-bearing deposits		31,210	31,540
Money market and interest-bearing checking deposits		20,952	22,556
Savings deposits		2,158	2,064
Customer certificates of deposit		2,438	2,806
Foreign office time deposits		23	19
Total interest-bearing deposits		25,571	27,445
Total deposits		56,781	58,985
Short-term borrowings		541	25
Accrued expenses and other liabilities		997	1,012
Medium- and long-term debt		5,143	5,160
Total liabilities		63,462	65,182
Common stock - $5 par value: Authorized - 325,000,000 shares; Issued - 228,164,824 shares		1,141	1,141
Capital surplus		2,110	2,135
Accumulated other comprehensive loss		(361)	(383)
Retained earnings		7,580	7,331
Less cost of common stock in treasury - 52,252,023 shares at 6/30/17 and 52,851,156 shares at 12/31/16		(2,485)	(2,428)
Total shareholders' equity		7,985	7,796
Total liabilities and shareholders' equity		$ 71,447	$ 72,978
[1]	Included auction-rate securities at amortized cost and fair value of $52 million and $51 million, respectively as of June 30, 2017 and $55 million and $54 million, respectively, as of December 31, 2016.

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2017	Dec. 31, 2016
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	52,252,023	52,851,156

Consolidated Statements Of Comp

Consolidated Statements Of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
INTEREST INCOME
Interest and fees on loans	$ 453	$ 406	$ 874	$ 812
Interest on investment securities	62	62	124	124
Interest on short-term investments	14	5	27	9
Total interest income	529	473	1,025	945
INTEREST EXPENSE
Interest on deposits	9	10	18	20
Interest on medium- and long-term debt	20	18	37	33
Total interest expense	29	28	55	53
Net interest income	500	445	970	892
Provision for credit losses	17	49	33	197
Net interest income after provision for credit losses	483	396	937	695
NONINTEREST INCOME
Card fees	80	76	157	148
Service charges on deposit accounts	57	55	115	110
Fiduciary income	51	49	100	95
Commercial lending fees	22	22	42	42
Letter of credit fees	11	13	23	26
Bank-owned life insurance	9	9	19	18
Foreign exchange income	11	11	22	21
Brokerage fees	6	5	11	9
Net securities losses	(2)	(1)	(2)	(3)
Other noninterest income	31	29	60	46
Total noninterest income	276	268	547	512
NONINTEREST EXPENSES
Salaries and benefits expense	219	247	452	495
Outside processing fee expense	88	83	175	161
Net occupancy expense	38	39	76	77
Equipment expense	11	14	22	27
Restructuring charges	14	53	25	53
Software expense	31	30	60	59
FDIC insurance expense	12	14	25	25
Advertising expense	7	6	11	10
Litigation-related expense	0	0	(2)	0
Other noninterest expenses	37	32	70	69
Total noninterest expenses	457	518	914	976
Income before income taxes	302	146	570	231
Provision for income taxes	99	42	165	67
Net Income	203	104	405	164
Less income allocated to participating securities	1	1	3	2
Net income attributable to common shares	$ 202	$ 103	$ 402	$ 162
Basic earnings per common share	$ 1.15	$ 0.60	$ 2.30	$ 0.94
Diluted earnings per common share	$ 1.13	$ 0.58	$ 2.24	$ 0.92
Comprehensive income	$ 221	$ 137	$ 427	$ 298
Cash dividends declared on common stock	$ 46	$ 38	$ 88	$ 75
Cash dividends declared per common share	$ 0.26	$ 0.22	$ 0.49	$ 0.43

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
BALANCE at Dec. 31, 2015	$ 7,560	$ 1,141	$ 2,173	$ (429)	$ 7,084	$ (2,409)
BALANCE (in shares) at Dec. 31, 2015		175.7
Net income	164				164
Other comprehensive income, net of tax	134			134
Cash dividends declared on common stock	(75)				(75)
Purchase of common stock	(114)					(114)
Purchase of common stock (in shares)		(2.9)
Net issuance of common stock under employee stock plans	0		(33)		(16)	49
Net issuance of common stock under employee stock plans (in shares)		1.1
Share-based compensation	25		25
BALANCE at Jun. 30, 2016	7,694	$ 1,141	2,165	(295)	7,157	(2,474)
BALANCE (in shares) at Jun. 30, 2016		173.9
BALANCE (Cumulative effect of change in accounting principle)	1		3		(2)
BALANCE at Dec. 31, 2016	7,796	$ 1,141	2,135	(383)	7,331	(2,428)
BALANCE (in shares) at Dec. 31, 2016		175.3
Net income	405				405
Other comprehensive income, net of tax	22			22
Cash dividends declared on common stock	(88)				(88)
Purchase of common stock	(257)					(257)
Purchase of common stock (in shares)		(3.7)
Net issuance of common stock under employee stock plans	82		(26)		(20)	128
Net issuance of common stock under employee stock plans (in shares)		2.8
Net issuance of common stock for warrants	0		(25)		(46)	71
Net issuance of common stock for warrants (in shares)		1.5
Share-based compensation	24		24
Other	0		(1)			1
Other (in shares)		0
BALANCE at Jun. 30, 2017	$ 7,985	$ 1,141	$ 2,110	$ (361)	$ 7,580	$ (2,485)
BALANCE (in shares) at Jun. 30, 2017		175.9

Consolidated Statements Of Cha6

Consolidated Statements Of Changes In Shareholders' Equity (Parenthetical) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Stockholders' Equity [Abstract]
Cash dividends declared on common stock, per share	$ 0.26	$ 0.22	$ 0.49	$ 0.43

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
OPERATING ACTIVITIES
Net income	$ 405	$ 164
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for credit losses	33	197
Benefit for deferred income taxes	(19)	(52)
Depreciation and amortization	60	59
Net periodic defined (credit) benefit cost	(9)	7
Share-based compensation expense	24	25
Net amortization of securities	3	4
Accretion of loan purchase discount	(2)	(3)
Net gains on sales of foreclosed property	(1)	(2)
Net change in accrued income receivable	(1)	(7)
Net change in accrued expenses payable	(17)	40
Other, net	180	(188)
Net cash provided by operating activities	656	244
INVESTING ACTIVITIES
Maturities and redemptions of investment securities available-for-sale	771	750
Sales of investment securities available-for-sale	1,259	0
Purchases of investment securities available-for-sale	(2,169)	(756)
Maturities and redemptions of investment securities held-to-maturity	153	175
Net change in loans	(370)	(1,392)
Proceeds from sales of foreclosed property	4	11
Net increase in premises and equipment	(27)	(54)
Purchases of Federal Home Loan Bank stock	(22)	(115)
Other, net	2	1
Net cash used in investing activities	(399)	(1,380)
FINANCING ACTIVITIES
Net change in deposits	(2,084)	(3,509)
Net change in short-term borrowings	516	(11)
Maturities of medium- and long-term debt	16	0
Issuances of medium- and long-term debt	0	2,800
Repurchases of common stock	(257)	(118)
Cash dividends paid on common stock	(81)	(74)
Issuances of common stock under employee stock plans	82	12
Other, net	(4)	(1)
Net cash used in financing activities	(1,844)	(901)
Net decrease in cash and cash equivalents	(1,587)	(2,037)
Cash and cash equivalents at beginning of period	7,218	6,147
Cash and cash equivalents at end of period	5,631	4,110
Interest paid	54	51
Income tax paid	130	60
Noncash investing and financing activities:
Loans transferred to other real estate	4	19
Loans transferred from held-for-sale to portfolio	$ 0	$ 10

Basis of Presentation and Accou

Basis of Presentation and Accounting Policies	6 Months Ended
	Jun. 30, 2017
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 six months ended June 30, 2017 are not necessarily indicative of the results that may be expected for the year ending December 31, 2017 . 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, 2016 . Share-Based Compensation Effective January 1, 2016, the Corporation adopted the provisions of Financial Accounting Standards Board (FASB) Accounting Standards Update (ASU) No. 2016-09, “Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payments Accounting” (ASU 2016-09). ASU 2016-09 provides for the election of an accounting policy as to the timing of when stock award forfeitures are recognized in compensation expense. The Corporation elected to account for forfeitures as they occur, rather than account for compensation cost based on an estimate of the number of awards that are expected to vest. The prior period effect of this policy election as of the beginning of the year was reported as "cumulative effect of change in accounting principle" in the accompanying Consolidated Statements of Changes in Shareholders’ Equity (unaudited). In addition, ASU 2016-09 requires excess tax benefits and deficiencies resulting from employee stock awards to be prospectively recognized as a component of income taxes. Previously, excess tax benefits and deficiencies were recognized in "capital surplus" in the Consolidated Statements of Changes in Shareholders' Equity. Net excess tax benefits for awards that vested, were exercised or expired included in the "provision for income taxes" totaled $5 million and $ 29 million for the three- and six-month periods ended June 30, 2017 , respectively. The Corporation also retrospectively adopted certain changes to the statement of cash flows in accordance with ASU 2016-09. Excess tax benefits must be classified as an operating activity, and cash paid to a tax authority by the Corporation when withholding shares from an employee’s award for tax-withholding purposes must be classified as a financing activity. Accordingly, the Corporation reclassified $4 million from operating activities to financing activities in the Consolidated Statements of Cash Flows (unaudited) pertaining to shares withheld from employee awards for tax withholding purposes for the six months ended June 30, 2016 . Recently Issued Accounting Pronouncements In March 2017, the FASB issued ASU No. 2017-07, “Compensation - Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost” (ASU 2017-07), which requires employers to report service cost as part of compensation expense and the other components of net benefit cost separately from service cost on the statement of income. ASU 2017-07 is effective for the Corporation on January 1, 2018. Early adoption is permitted. The Corporation does not expect the new guidance to have a material impact on its financial condition or results of operation.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2017
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. Trading securities, investment securities available-for-sale, derivatives and deferred compensation plan 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, 2016 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 LIABLILITIES 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 June 30, 2017 and December 31, 2016 . (in millions) Total Level 1 Level 2 Level 3 June 30, 2017 Trading securities: Deferred compensation plan assets $ 88 $ 88 $ — $ — Investment securities available-for-sale: U.S. Treasury and other U.S. government agency securities 2,773 2,773 — — Residential mortgage-backed securities (a) 8,057 — 8,057 — State and municipal securities 5 — — 5 (b) Equity and other non-debt securities 109 63 — 46 (b) Total investment securities available-for-sale 10,944 2,836 8,057 51 Derivative assets: Interest rate contracts 96 — 83 13 Energy derivative contracts 104 — 104 — Foreign exchange contracts 36 — 36 — Warrants 2 — — 2 Total derivative assets 238 — 223 15 Total assets at fair value $ 11,270 $ 2,924 $ 8,280 $ 66 Derivative liabilities: Interest rate contracts $ 47 $ — $ 47 $ — Energy derivative contracts 102 — 102 — Foreign exchange contracts 34 — 34 — Total derivative liabilities 183 — 183 — Deferred compensation plan liabilities 88 88 — — Total liabilities at fair value $ 271 $ 88 $ 183 $ — (a) Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises. (b) Auction-rate securities. (in millions) Total Level 1 Level 2 Level 3 December 31, 2016 Trading securities: Deferred compensation plan assets $ 87 $ 87 $ — $ — Equity and other non-debt securities 1 1 — — Total trading securities 88 88 — — Investment securities available-for-sale: U.S. Treasury and other U.S. government agency securities 2,779 2,779 — — Residential mortgage-backed securities (a) 7,872 — 7,872 — State and municipal securities 7 — — 7 (b) Equity and other non-debt securities 129 82 — 47 (b) Total investment securities available-for-sale 10,787 2,861 7,872 54 Derivative assets: Interest rate contracts 223 — 212 11 Energy derivative contracts 146 — 146 — Foreign exchange contracts 38 — 38 — Warrants 3 — — 3 Total derivative assets 410 — 396 14 Total assets at fair value $ 11,285 $ 2,949 $ 8,268 $ 68 Derivative liabilities: Interest rate contracts $ 81 $ — $ 81 $ — Energy derivative contracts 144 — 144 — Foreign exchange contracts 29 — 29 — Total derivative liabilities 254 — 254 — Deferred compensation plan liabilities 87 87 — — Total liabilities at fair value $ 341 $ 87 $ 254 $ — (a) Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises. (b) Auction-rate securities. 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 six-month periods ended June 30, 2017 and 2016 . The following table summarizes the changes in Level 3 assets and liabilities measured at fair value on a recurring basis for the three- and six-month periods ended June 30, 2017 and 2016 . Net Realized/Unrealized Gains (Losses) (Pretax) Balance at Beginning of Period Recorded in Earnings Recorded in Other Comprehensive Income Balance at End of Period (in millions) Realized Unrealized Redemptions Sales Three Months Ended June 30, 2017 Investment securities available-for-sale: State and municipal securities (a) $ 5 $ — $ — $ — $ — $ — $ 5 Equity and other non-debt securities (a) 46 — — — — — 46 Total investment securities available-for-sale 51 — — — — — 51 Derivative assets: Interest rate contracts 11 — 2 (b) — — — 13 Warrants 2 4 (b) — — — (4 ) 2 Three Months Ended June 30, 2016 Investment securities available-for-sale: State and municipal securities (a) $ 9 $ — $ — $ — $ (1 ) $ — $ 8 Corporate debt securities (a) 1 — — — — — 1 Equity and other non-debt securities (a) 51 — — (3 ) — — 48 Total investment securities available-for-sale 61 — — (3 ) (1 ) — 57 Derivative assets: Interest rate contracts 20 — 7 (b) — — — 27 Warrants 2 — 1 (b) — — (1 ) 2 Six Months Ended June 30, 2017 Investment securities available-for-sale: State and municipal securities (a) $ 7 $ — $ — $ — $ (2 ) $ — $ 5 Equity and other non-debt securities (a) 47 — — — (1 ) — 46 Total investment securities available-for-sale 54 — — — (3 ) — 51 Derivative assets: Interest rate contracts 11 — 2 (b) — — — 13 Warrants 3 5 (b) (1 ) (b) — — (5 ) 2 Six Months Ended June 30, 2016 Investment securities available-for-sale: State and municipal securities (a) $ 9 $ — $ — $ — $ (1 ) $ — $ 8 Corporate debt securities (a) 1 — — — — — 1 Equity and other non-debt securities (a) 67 — — (4 ) (15 ) — 48 Total investment securities available-for-sale 77 — — (4 ) (16 ) — 57 Derivative assets: Interest rate contracts 9 — 18 (b) — — — 27 Warrants 2 — 1 (b) — — (1 ) 2 (a) Auction-rate securities. (b) Realized and unrealized gains and losses due to changes in fair value recorded in "other noninterest income" on the consolidated statements of comprehensive income. ASSETS AND LIABILITIES RECORDED AT FAIR VALUE ON A NONRECURRING BASIS The Corporation may be required, from time to time, 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 that were recognized at fair value below cost at the end of the period. The following table presents assets recorded at fair value on a nonrecurring basis at June 30, 2017 and December 31, 2016 . No liabilities were recorded at fair value on a nonrecurring basis at June 30, 2017 and December 31, 2016 . (in millions) Level 3 June 30, 2017 Loans: Commercial $ 248 Commercial mortgage 18 International 5 Total loans 271 Other real estate 13 Total assets at fair value $ 284 December 31, 2016 Loans: Commercial $ 256 Commercial mortgage 15 International 11 Total loans 282 Other real estate 1 Total assets at fair value $ 283 Level 3 assets recorded at fair value on a nonrecurring basis at June 30, 2017 and December 31, 2016 included loans for which a specific allowance was established based on the fair value of collateral and other real estate for which fair value of the properties was less than the cost basis. For both asset classes, 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. The following table presents quantitative information related to the significant unobservable inputs utilized in the Corporation's Level 3 recurring fair value measurement as of June 30, 2017 and December 31, 2016 . The Corporation's Level 3 recurring fair value measurements primarily include auction-rate securities where fair value is determined using an income approach based on a discounted cash flow model and certain interest rate derivative contracts where credit valuation adjustments are significant to the overall fair value of the derivative. The inputs in the table below reflect management's expectation of continued illiquidity in the secondary auction-rate securities market due to a lack of market activity for the issuers remaining in the portfolio, a lack of market incentives for issuer redemptions, and the expectation for a continuing low interest rate environment. The workout periods reflect management's expectation of the pace at which short-term interest rates could rise at each respective period. Discounted Cash Flow Model Unobservable Input Fair Value (in millions) Discount Rate Workout Period (in years) June 30, 2017 State and municipal securities (a) $ 5 5% - 7% 1 - 2 Equity and other non-debt securities (a) 46 7% - 9% 1 - 2 December 31, 2016 State and municipal securities (a) $ 7 4% - 6% 1 - 2 Equity and other non-debt securities (a) 47 7% - 9% 1 - 2 (a) Auction-rate securities. 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 June 30, 2017 Assets Cash and due from banks $ 1,372 $ 1,372 $ 1,372 $ — $ — Interest-bearing deposits with banks 4,259 4,259 4,259 — — Investment securities held-to-maturity 1,430 1,424 — 1,424 — Loans held-for-sale 1 1 — 1 — Total loans, net of allowance for loan losses (a) 48,703 48,468 — — 48,468 Customers’ liability on acceptances outstanding 3 3 3 — — Restricted equity investments 228 228 228 — — Nonmarketable equity securities (b) 6 10 Liabilities Demand deposits (noninterest-bearing) 31,210 31,210 — 31,210 — Interest-bearing deposits 23,133 23,133 — 23,133 — Customer certificates of deposit 2,438 2,418 — 2,418 — Total deposits 56,781 56,761 — 56,761 — Short-term borrowings 541 541 541 — — Acceptances outstanding 3 3 3 — — Medium- and long-term debt 5,143 5,138 — 5,138 — Credit-related financial instruments (76 ) (76 ) — — (76 ) December 31, 2016 Assets Cash and due from banks $ 1,249 $ 1,249 $ 1,249 $ — $ — Interest-bearing deposits with banks 5,969 5,969 5,969 — — Investment securities held-to-maturity 1,582 1,576 — 1,576 — Loans held-for-sale 4 4 — 4 — Total loans, net of allowance for loan losses (a) 48,358 48,250 — — 48,250 Customers’ liability on acceptances outstanding 5 5 5 — — Restricted equity investments 207 207 207 — — Nonmarketable equity securities (b) 11 16 Liabilities Demand deposits (noninterest-bearing) 31,540 31,540 — 31,540 — Interest-bearing deposits 24,639 24,639 — 24,639 — Customer certificates of deposit 2,806 2,731 — 2,731 — Total deposits 58,985 58,910 — 58,910 — Short-term borrowings 25 25 25 — — Acceptances outstanding 5 5 5 — — Medium- and long-term debt 5,160 5,132 — 5,132 — Credit-related financial instruments (73 ) (73 ) — — (73 ) (a) Included $271 million and $282 million of impaired loans recorded at fair value on a nonrecurring basis at June 30, 2017 and December 31, 2016 , 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	6 Months Ended
	Jun. 30, 2017
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 June 30, 2017 Investment securities available-for-sale: U.S. Treasury and other U.S. government agency securities $ 2,762 $ 11 $ — $ 2,773 Residential mortgage-backed securities (a) 8,089 45 77 8,057 State and municipal securities 5 — — 5 Equity and other non-debt securities 109 1 1 109 Total investment securities available-for-sale (b) $ 10,965 $ 57 $ 78 $ 10,944 Investment securities held-to-maturity (c): Residential mortgage-backed securities (a) $ 1,430 $ 1 $ 7 $ 1,424 December 31, 2016 Investment securities available-for-sale: U.S. Treasury and other U.S. government agency securities $ 2,772 $ 8 $ 1 $ 2,779 Residential mortgage-backed securities (a) 7,921 48 97 7,872 State and municipal securities 7 — — 7 Equity and other non-debt securities 129 1 1 129 Total investment securities available-for-sale (b) $ 10,829 $ 57 $ 99 $ 10,787 Investment securities held-to-maturity (c): Residential mortgage-backed securities (a) $ 1,582 $ 1 $ 7 $ 1,576 (a) Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises. (b) Included auction-rate securities at amortized cost and fair value of $52 million and $51 million , respectively as of June 30, 2017 and $55 million and $54 million , respectively, as of December 31, 2016 . (c) The amortized cost of investment securities held-to-maturity included net unrealized losses of $11 million at June 30, 2017 and $12 million at December 31, 2016 related to securities transferred from available-for-sale, which are included in accumulated other comprehensive loss. A summary of the Corporation’s investment securities in an unrealized loss position as of June 30, 2017 and December 31, 2016 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 June 30, 2017 U.S. Treasury and other U.S. government agency securities $ 301 $ — (c) $ — $ — $ 301 $ — (c) Residential mortgage-backed securities (a) 4,667 69 1,073 27 5,740 96 State and municipal securities (b) — — 5 — (c) 5 — (c) Equity and other non-debt securities (b) — — 46 1 46 1 Total temporarily impaired securities $ 4,968 $ 69 $ 1,124 $ 28 $ 6,092 $ 97 December 31, 2016 U.S. Treasury and other U.S. government agency securities $ 527 $ 1 $ — $ — $ 527 $ 1 Residential mortgage-backed securities (a) 4,992 87 1,177 32 6,169 119 State and municipal securities (b) — — 7 — (c) 7 — (c) Equity and other non-debt securities (b) 36 — (c) 11 — (c) 47 — (c) Total temporarily impaired securities $ 5,555 $ 88 $ 1,195 $ 32 $ 6,750 $ 120 (a) Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises. (b) Primarily auction-rate securities. (c) Unrealized losses less than $0.5 million. At June 30, 2017 , the Corporation had 233 securities in an unrealized loss position with no credit impairment, including 4 U.S. Treasury securities, 188 residential mortgage-backed securities, 28 equity and other non-debt auction-rate preferred securities and 13 state and municipal auction-rate securities. As of June 30, 2017 , approximately 96 percent of the aggregate par value of auction-rate securities have been redeemed or sold since acquisition, of which approximately 90 percent were redeemed at or above cost. The unrealized losses for these securities resulted from changes in market interest rates and liquidity. 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 June 30, 2017 . Sales, calls and write-downs of investment securities available-for-sale resulted in the following gains and losses recorded in “net securities gains (losses)” on the consolidated statements of comprehensive income, computed based on the adjusted cost of the specific security. Three Months Ended June 30, Six Months Ended June 30, (in millions) 2017 2016 2017 2016 Securities gains $ — $ — $ 1 $ — Securities losses (a) (2 ) (1 ) (3 ) (3 ) Net securities losses $ (2 ) $ (1 ) $ (2 ) $ (3 ) (a) Primarily charges related to a derivative contract tied to the conversion rate of Visa Class B shares. 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) Available-for-sale Held-to-maturity June 30, 2017 Amortized Cost Fair Value Amortized Cost Fair Value Contractual maturity Within one year $ 20 $ 20 $ — $ — After one year through five years 2,991 3,002 — — After five years through ten years 1,833 1,861 21 20 After ten years 6,012 5,952 1,409 1,404 Subtotal 10,856 10,835 1,430 1,424 Equity and other non-debt securities 109 109 — — Total investment securities $ 10,965 $ 10,944 $ 1,430 $ 1,424 Included in the contractual maturity distribution in the table above were residential mortgage-backed securities available-for-sale with total amortized cost and fair value of $8.1 billion and residential mortgage-backed securities held-to-maturity with a total amortized cost and fair value of $1.4 billion . The actual cash flows of mortgage-backed securities may differ from contractual maturity as the borrowers of the underlying loans may exercise prepayment options. At June 30, 2017 , investment securities with a carrying value of $1.1 billion were pledged where permitted or required by law to secure $600 million of liabilities, primarily public and other deposits of state and local government agencies and derivative instruments.

Credit Quality And Allowance Fo

Credit Quality And Allowance For Credit Losses	6 Months Ended
	Jun. 30, 2017
Credit Quality And Allowance For Credit Losses [Abstract]
Credit Quality And Allowance For Credit Losses	CREDIT QUALITY AND ALLOWANCE FOR CREDIT LOSSES 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 June 30, 2017 Business loans: Commercial $ 38 $ 11 $ 23 $ 72 $ 379 $ 30,998 $ 31,449 Real estate construction: Commercial Real Estate business line (a) — — — — — 2,560 2,560 Other business lines (b) — 1 — 1 — 296 297 Total real estate construction — 1 — 1 — 2,856 2,857 Commercial mortgage: Commercial Real Estate business line (a) 16 — — 16 9 1,801 1,826 Other business lines (b) 2 3 7 12 32 7,104 7,148 Total commercial mortgage 18 3 7 28 41 8,905 8,974 Lease financing — — — — 8 464 472 International 8 — — 8 6 1,131 1,145 Total business loans 64 15 30 109 434 44,354 44,897 Retail loans: Residential mortgage 8 10 — 18 36 1,922 1,976 Consumer: Home equity 6 2 — 8 23 1,765 1,796 Other consumer 1 — — 1 — 738 739 Total consumer 7 2 — 9 23 2,503 2,535 Total retail loans 15 12 — 27 59 4,425 4,511 Total loans $ 79 $ 27 $ 30 $ 136 $ 493 $ 48,779 $ 49,408 December 31, 2016 Business loans: Commercial $ 30 $ 12 $ 14 $ 56 $ 445 $ 30,493 $ 30,994 Real estate construction: Commercial Real Estate business line (a) — — — — — 2,485 2,485 Other business lines (b) — — — — — 384 384 Total real estate construction — — — — — 2,869 2,869 Commercial mortgage: Commercial Real Estate business line (a) 5 — — 5 9 2,004 2,018 Other business lines (b) 58 5 5 68 37 6,808 6,913 Total commercial mortgage 63 5 5 73 46 8,812 8,931 Lease financing — — — — 6 566 572 International 1 — — 1 14 1,243 1,258 Total business loans 94 17 19 130 511 43,983 44,624 Retail loans: Residential mortgage 7 3 — 10 39 1,893 1,942 Consumer: Home equity 4 3 — 7 28 1,765 1,800 Other consumer 1 — — 1 4 717 722 Total consumer 5 3 — 8 32 2,482 2,522 Total retail loans 12 6 — 18 71 4,375 4,464 Total loans $ 106 $ 23 $ 19 $ 148 $ 582 $ 48,358 $ 49,088 (a) Primarily loans to real estate developers. (b) Primarily loans secured by owner-occupied real estate. 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 June 30, 2017 Business loans: Commercial $ 29,492 $ 661 $ 917 $ 379 $ 31,449 Real estate construction: Commercial Real Estate business line (e) 2,545 15 — — 2,560 Other business lines (f) 297 — — — 297 Total real estate construction 2,842 15 — — 2,857 Commercial mortgage: Commercial Real Estate business line (e) 1,744 66 7 9 1,826 Other business lines (f) 6,894 110 112 32 7,148 Total commercial mortgage 8,638 176 119 41 8,974 Lease financing 443 20 1 8 472 International 1,064 57 18 6 1,145 Total business loans 42,479 929 1,055 434 44,897 Retail loans: Residential mortgage 1,930 10 — 36 1,976 Consumer: Home equity 1,769 1 3 23 1,796 Other consumer 738 1 — — 739 Total consumer 2,507 2 3 23 2,535 Total retail loans 4,437 12 3 59 4,511 Total loans $ 46,916 $ 941 $ 1,058 $ 493 $ 49,408 December 31, 2016 Business loans: Commercial $ 28,616 $ 944 $ 989 $ 445 $ 30,994 Real estate construction: Commercial Real Estate business line (e) 2,485 — — — 2,485 Other business lines (f) 381 — 3 — 384 Total real estate construction 2,866 — 3 — 2,869 Commercial mortgage: Commercial Real Estate business line (e) 1,970 19 20 9 2,018 Other business lines (f) 6,645 109 122 37 6,913 Total commercial mortgage 8,615 128 142 46 8,931 Lease financing 550 11 5 6 572 International 1,200 22 22 14 1,258 Total business loans 41,847 1,105 1,161 511 44,624 Retail loans: Residential mortgage 1,900 3 — 39 1,942 Consumer: Home equity 1,767 1 4 28 1,800 Other consumer 718 — — 4 722 Total consumer 2,485 1 4 32 2,522 Total retail loans 4,385 4 4 71 4,464 Total loans $ 46,232 $ 1,109 $ 1,165 $ 582 $ 49,088 (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. (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 page F-56 in the Corporation's 2016 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. The following table summarizes nonperforming assets. (in millions) June 30, 2017 December 31, 2016 Nonaccrual loans $ 493 $ 582 Reduced-rate loans (a) 8 8 Total nonperforming loans 501 590 Foreclosed property (b) 18 17 Total nonperforming assets $ 519 $ 607 (a) There were no reduced-rate business loans at both June 30, 2017 and December 31, 2016 . Reduced-rate retail loans were $8 million at both June 30, 2017 and December 31, 2016 . (b) Included $4 million and $3 million of foreclosed residential real estate properties at June 30, 2017 and December 31, 2016 , respectively. There were no retail loans secured by residential real estate properties in process of foreclosure included in nonaccrual loans at both June 30, 2017 and December 31, 2016 . Allowance for Credit Losses The following table details the changes in the allowance for loan losses and related loan amounts. 2017 2016 (in millions) Business Loans Retail Loans Total Business Loans Retail Loans Total Three Months Ended June 30 Allowance for loan losses: Balance at beginning of period $ 661 $ 47 $ 708 $ 674 $ 50 $ 724 Loan charge-offs (37 ) (2 ) (39 ) (52 ) (2 ) (54 ) Recoveries on loans previously charged-off 20 1 21 11 1 12 Net loan charge-offs (17 ) (1 ) (18 ) (41 ) (1 ) (42 ) Provision for loan losses 17 (2 ) 15 49 (2 ) 47 Balance at end of period $ 661 $ 44 $ 705 $ 682 $ 47 $ 729 Six Months Ended June 30 Allowance for loan losses: Balance at beginning of period $ 682 $ 48 $ 730 $ 579 $ 55 $ 634 Loan charge-offs (79 ) (4 ) (83 ) (127 ) (4 ) (131 ) Recoveries on loans previously charged-off 29 3 32 35 2 37 Net loan charge-offs (50 ) (1 ) (51 ) (92 ) (2 ) (94 ) Provision for loan losses 29 (3 ) 26 194 (6 ) 188 Foreign currency translation adjustment — — — 1 — 1 Balance at end of period $ 661 $ 44 $ 705 $ 682 $ 47 $ 729 As a percentage of total loans 1.47 % 0.98 % 1.43 % 1.48 % 1.07 % 1.45 % June 30 Allowance for loan losses: Individually evaluated for impairment $ 93 $ 1 $ 94 $ 112 $ — $ 112 Collectively evaluated for impairment 568 43 611 570 47 617 Total allowance for loan losses $ 661 $ 44 $ 705 $ 682 $ 47 $ 729 Loans: Individually evaluated for impairment $ 509 $ 41 $ 550 $ 646 $ 26 $ 672 Collectively evaluated for impairment 44,388 4,470 48,858 45,354 4,354 49,708 Total loans evaluated for impairment $ 44,897 $ 4,511 $ 49,408 $ 46,000 $ 4,380 $ 50,380 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 June 30, Six Months Ended June 30, (in millions) 2017 2016 2017 2016 Balance at beginning of period $ 46 $ 46 $ 41 $ 45 Charge-offs on lending-related commitments (a) — (5 ) — (11 ) Provision for credit losses on lending-related commitments 2 2 7 9 Balance at end of period $ 48 $ 43 $ 48 $ 43 (a) Charge-offs result from the sale of unfunded lending-related commitments. 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 June 30, 2017 Business loans: Commercial $ 115 $ 347 $ 462 $ 569 $ 87 Commercial mortgage: Commercial Real Estate business line (a) — 7 7 15 4 Other business lines (b) 1 33 34 40 1 Total commercial mortgage 1 40 41 55 5 International — 6 6 14 1 Total business loans 116 393 509 638 93 Retail loans: Residential mortgage 19 8 27 28 1 Consumer: Home equity 12 — 12 13 — Other consumer 2 — 2 2 — Total consumer 14 — 14 15 — Total retail loans (c) 33 8 41 43 1 Total individually evaluated impaired loans $ 149 $ 401 $ 550 $ 681 $ 94 December 31, 2016 Business loans: Commercial $ 90 $ 423 $ 513 $ 608 $ 80 Commercial mortgage: Commercial Real Estate business line (a) — 7 7 15 1 Other business lines (b) 2 30 32 40 3 Total commercial mortgage 2 37 39 55 4 International 3 11 14 20 2 Total business loans 95 471 566 683 86 Retail loans: Residential mortgage 19 9 28 30 2 Consumer: Home equity 15 — 15 19 — Other consumer 2 3 5 6 1 Total consumer 17 3 20 25 1 Total retail loans (c) 36 12 48 55 3 Total individually evaluated impaired loans $ 131 $ 483 $ 614 $ 738 $ 89 (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. The following table presents information regarding average individually evaluated impaired loans and the related interest recognized. Interest income recognized for the period primarily related to performing restructured loans. Individually Evaluated Impaired Loans 2017 2016 (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 June 30 Business loans: Commercial $ 473 $ 2 $ 639 $ 2 Commercial mortgage: Commercial Real Estate business line (a) 7 — 8 — Other business lines (b) 35 — 31 — Total commercial mortgage 42 — 39 — International 7 — 23 — Total business loans 522 2 701 2 Retail loans: Residential mortgage 27 — 11 — Consumer loans: Home equity 12 — 11 — Other consumer 2 — 3 — Total consumer 14 — 14 — Total retail loans 41 — 25 — Total individually evaluated impaired loans $ 563 $ 2 $ 726 $ 2 Six Months Ended June 30 Business loans: Commercial $ 487 $ 4 $ 537 $ 6 Commercial mortgage: Commercial Real Estate business line (a) 7 — 10 — Other business lines (b) 34 — 32 — Total commercial mortgage 41 — 42 — International 9 — 19 — Total business loans 537 4 598 6 Retail loans: Residential mortgage 27 — 12 — Consumer: Home equity 13 — 12 — Other consumer 3 — 4 — Total consumer 16 — 16 — Total retail loans 43 — 28 — Total individually evaluated impaired loans $ 580 $ 4 $ 626 $ 6 (a) Primarily loans to real estate developers. (b) Primarily loans secured by owner-occupied real estate. Troubled Debt Restructurings The following tables detail the recorded balance at June 30, 2017 and 2016 of loans considered to be troubled debt restructurings (TDRs) that were restructured during the three- and six-month periods ended June 30, 2017 and 2016 , 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. 2017 2016 Type of Modification Type of Modification (in millions) Principal Deferrals (a) Interest Rate Reductions AB Note Restructures (b) Total Modifications Principal Deferrals (a) Interest Rate Reductions AB Note Restructures (b) Total Modifications Three Months Ended June 30 Business loans: Commercial $ 47 $ — $ 36 $ 83 $ 18 $ — $ 20 $ 38 Commercial mortgage: Other business lines (c) 1 — — 1 1 — — 1 Total business loans 48 — 36 84 19 — 20 39 Retail loans: Consumer: Home equity (d) — 1 — 1 1 — — 1 Total retail loans — 1 — 1 1 — — 1 Total loans $ 48 $ 1 $ 36 $ 85 $ 20 $ — $ 20 $ 40 Six Months Ended June 30 Business loans: Commercial $ 96 $ — $ 36 $ 132 $ 107 $ — $ 26 $ 133 Commercial mortgage: Other business lines (c) 4 — — 4 2 — — 2 International — — — — — — 10 10 Total business loans 100 — 36 136 109 — 36 145 Retail loans: Residential mortgage — — — — — 2 — 2 Consumer: Home equity (d) 1 2 — 3 1 — — 1 Total retail loans 1 2 — 3 1 2 — 3 Total loans $ 101 $ 2 $ 36 $ 139 $ 110 $ 2 $ 36 $ 148 (a) Primarily represents loan balances where terms were extended 90 days or more at or above contractual interest rates. (b) Loan restructurings whereby the original loan is restructured into two notes: an "A" note, which generally reflects the portion of the modified loan which is expected to be collected; and a "B" note, which is generally fully charged off. (c) Primarily loans secured by owner-occupied real estate. (d) Includes bankruptcy loans for which the court has discharged the borrower's obligation and the borrower has not reaffirmed the debt. Commitments to lend additional funds to borrowers whose terms have been modified in TDRs were $47 million at June 30, 2017 and $24 million at December 31, 2016 . The majority of the modifications considered to be TDRs that occurred during the six months ended June 30, 2017 and 2016 were principal deferrals. The Corporation charges interest on principal balances outstanding during deferral periods. Additionally, none of the modifications involved forgiveness of principal. As a result, the current and future financial effects of the recorded balance of loans considered to be TDRs that were restructured during the six months ended June 30, 2017 and 2016 were insignificant. On an ongoing basis, the Corporation monitors the performance of modified loans to their restructured terms. In the event of a subsequent default, the allowance for loan losses continues to be reassessed on the basis of an individual evaluation of the loan. The following table presents information regarding the recorded balance at June 30, 2017 and 2016 of loans modified by principal deferral during the twelve-month periods ended June 30, 2017 and 2016 , and those principal deferrals which experienced a subsequent default during the three- and six-month periods ended June 30, 2017 and 2016 . 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. 2017 2016 (in millions) Balance at June 30 Subsequent Default in the Three Months Ended June 30 Subsequent Default in the Six Months Ended June 30 Balance at June 30 Subsequent Default in the Three Months Ended June 30 Subsequent Default in the Six Months Ended June 30 Principal deferrals: Business loans: Commercial $ 141 $ — $ — $ 233 $ 21 $ 21 Commercial mortgage: Commercial Real Estate business line (a) 1 — — 4 1 1 Other business lines (b) 7 — 7 — 6 Total commercial mortgage 8 — — 11 1 7 International — — — 1 — 1 Total business loans 149 — — 245 22 29 Retail loans: Consumer: Home equity 1 (c) — — 2 (c) — — Total principal deferrals $ 151 $ — $ — $ 247 $ 22 $ 29 (a) Primarily loans to real estate developers. (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. During the twelve-month periods ended June 30, 2017 and 2016 , loans with a carrying value of $3 million and $4 million , respectively, were modified by interest rate reduction. During the twelve-month periods ended June 30, 2017 and 2016 , loans with a carrying value of $68 million and $36 million , respectively, were restructured into two notes (AB note restructures). For reduced-rate loans and AB note restructures, a subsequent payment default is defined in terms of delinquency, when a principal or interest payment is 90 days past due. There were no subsequent payment defaults of reduced-rate loans or AB note restructures during the three- and six-month periods ended June 30, 2017 and no subsequent payment defaults of reduced-rate loans and $1 million of subsequent payment defaults of AB note restructures during the three- and six-month periods ended June 30, 2016 .

Derivative And Credit-Related F

Derivative And Credit-Related Financial Instruments	6 Months Ended
	Jun. 30, 2017
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 June 30, 2017 , counterparties with bilateral collateral agreements had pledged $11 million of marketable investment securities and deposited $77 million of cash with the Corporation to secure the fair value of contracts in an unrealized gain position, and the Corporation had pledged $21 million of marketable investment securities and posted $5 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 June 30, 2017 . 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 conducting hedging transactions 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 June 30, 2017 and December 31, 2016 . The table excludes commitments and warrants accounted for as derivatives. June 30, 2017 December 31, 2016 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 (b) $ 2,275 $ 10 $ — $ 2,275 $ 92 $ 4 Derivatives used as economic hedges Foreign exchange contracts: Spot, forwards and swaps 703 — 4 717 2 2 Total risk management purposes 2,978 10 4 2,992 94 6 Customer-initiated and other activities Interest rate contracts: Caps and floors written 627 — — 436 — 1 Caps and floors purchased 627 — — 436 1 — Swaps (b) 13,003 86 47 12,451 130 76 Total interest rate contracts 14,257 86 47 13,323 131 77 Energy contracts: Caps and floors written 297 — 19 419 1 31 Caps and floors purchased 297 19 — 419 31 1 Swaps 1,309 85 83 1,389 114 112 Total energy contracts 1,903 104 102 2,227 146 144 Foreign exchange contracts: Spot, forwards, options and swaps 1,583 36 30 1,509 36 27 Total customer-initiated and other activities 17,743 226 179 17,059 313 248 Total gross derivatives $ 20,721 236 183 $ 20,051 407 254 Amounts offset in the consolidated balance sheets: Netting adjustment - Offsetting derivative assets/liabilities (54 ) (54 ) (84 ) (84 ) Netting adjustment - Cash collateral received/posted (68 ) (4 ) (47 ) (45 ) Net derivatives included in the consolidated balance sheets (c) 114 125 276 125 Amounts not offset in the consolidated balance sheets: Marketable securities pledged under bilateral collateral agreements (10 ) (16 ) (19 ) (8 ) Net derivatives after deducting amounts not offset in the consolidated balance sheets $ 104 $ 109 $ 257 $ 117 (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) Due to clearinghouse rule changes, beginning January 1, 2017, variation margin payments are treated as settlements of derivative exposure rather than as collateral. As a result, these payments are now considered in determining the fair value of centrally cleared derivatives, resulting in centrally cleared derivatives having a fair value of approximately zero. (c) 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 $5 million at both June 30, 2017 and December 31, 2016 . 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. These instruments generated net interest income of $10 million and $16 million for the three months ended June 30, 2017 and 2016 , respectively, and $20 million and $33 million for the six months ended June 30, 2017 and 2016 , respectively. These hedges have been highly effective, with no ineffectiveness net gains or losses recognized for both the three-month periods ended June 30, 2017 and 2016 as well as the six-month period ended June 30, 2017. An ineffectiveness net gain of $3 million was included in "other noninterest income" in the consolidated statements of comprehensive income for the six months ended June 30, 2016 . The following table summarizes the expected weighted average remaining maturity of the notional amount of risk management interest rate swaps and the weighted average interest rates associated with amounts expected to be received or paid on interest rate swap agreements as of June 30, 2017 and December 31, 2016 . Weighted Average (dollar amounts in millions) Notional Amount Remaining Maturity (in years) Receive Rate Pay Rate (a) June 30, 2017 Swaps - fair value - receive fixed/pay floating rate Medium- and long-term debt designation $ 2,275 4.0 3.69 % 1.98 % December 31, 2016 Swaps - fair value - receive fixed/pay floating rate Medium- and long-term debt designation 2,275 4.5 3.69 1.80 (a) Variable rates paid on receive fixed swaps are based on six-month LIBOR rates in effect at June 30, 2017 and December 31, 2016 . 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 six-month periods ended June 30, 2017 , respectively, and $1 million of net gains for both the three- and six-month periods ended June 30, 2016 . 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 June 30, Six Months Ended June 30, (in millions) Location of Gain 2017 2016 2017 2016 Interest rate contracts Other noninterest income $ 7 $ 6 $ 13 $ 8 Energy contracts Other noninterest income 1 1 1 1 Foreign exchange contracts Foreign exchange income 11 9 22 19 Total $ 19 $ 16 $ 36 $ 28 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) June 30, 2017 December 31, 2016 Unused commitments to extend credit: Commercial and other $ 22,450 $ 24,333 Bankcard, revolving check credit and home equity loan commitments 2,849 2,658 Total unused commitments to extend credit $ 25,299 $ 26,991 Standby letters of credit $ 3,436 $ 3,623 Commercial letters of credit 40 46 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 $48 million and $41 million at June 30, 2017 and December 31, 2016 , 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 $29 million at both June 30, 2017 and December 31, 2016 , 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 2023 . 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 $250 million and $255 million , respectively, of the $3.5 billion and $3.7 billion standby and commercial letters of credit outstanding at June 30, 2017 and December 31, 2016 , respectively. 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 $47 million at June 30, 2017 , including $28 million in deferred fees and $19 million in the allowance for credit losses on lending-related commitments. At December 31, 2016 , the comparable amounts were $44 million , $32 million and $12 million , respectively. The following table presents a summary of criticized standby and commercial letters of credit at June 30, 2017 and December 31, 2016 . 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) June 30, 2017 December 31, 2016 Total criticized standby and commercial letters of credit $ 103 $ 135 As a percentage of total outstanding standby and commercial letters of credit 3.0 % 3.7 % 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 June 30, 2017 and December 31, 2016 , the total notional amount of the credit risk participation agreements was approximately $577 million and $458 million , respectively, and the fair value, included in customer-initiated interest rate contracts recorded in "accrued expenses and other liabilities" on the consolidated balance sheets, 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 approximately $2 million and $3 million at June 30, 2017 and December 31, 2016 , 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 June 30, 2017 , the weighted average remaining maturity of outstanding credit risk participation agreements was 2.5 years.

Variable Interest Entities (VIE

Variable Interest Entities (VIEs)	6 Months Ended
	Jun. 30, 2017
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 which invest in community development projects which generate similar tax credits to investors. 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. Exposure to loss as a result of the Corporation’s involvement with LIHTC entities at June 30, 2017 was limited to approximately $424 million . Ownership interests in other community development projects which generate similar tax credits to investors (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 other tax credit entities at June 30, 2017 was limited to approximately $7 million . 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 ( $172 million at June 30, 2017 ). 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 six months ended June 30, 2017 and 2016 . 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 June 30, Six Months Ended June 30, (in millions) 2017 2016 2017 2016 Other noninterest income: Amortization of other tax credit investments $ — $ — $ 1 $ — Provision for income taxes: Amortization of LIHTC investments 16 16 32 32 Low income housing tax credits (16 ) (15 ) (31 ) (31 ) Other tax benefits related to tax credit entities (6 ) (6 ) (12 ) (12 ) Total provision for income taxes $ (6 ) $ (5 ) $ (11 ) $ (11 ) For further information on the Corporation’s consolidation policy, see note 1 to the consolidated financial statements in the Corporation's 2016 Annual Report.

Medium- And Long-Term Debt

Medium- And Long-Term Debt	6 Months Ended
	Jun. 30, 2017
Debt Disclosure [Abstract]
Medium- And Long-Term Debt	MEDIUM- AND LONG-TERM DEBT Medium- and long-term debt is summarized as follows: (in millions) June 30, 2017 December 31, 2016 Parent company Subordinated notes: 3.80% subordinated notes due 2026 (a) $ 258 $ 256 Medium-term notes: 2.125% notes due 2019 (a) 349 348 Total parent company 607 604 Subsidiaries Subordinated notes: 5.20% subordinated notes due 2017 (a) 502 511 4.00% subordinated notes due 2025 (a) 351 347 7.875% subordinated notes due 2026 (a) 213 215 Total subordinated notes 1,066 1,073 Medium-term notes: 2.50% notes due 2020 (a) 670 667 Federal Home Loan Bank (FHLB) advances: Floating-rate based on FHLB auction rate due 2026 2,800 2,800 Other notes: 6.0% - 6.4% fixed-rate notes due 2018 to 2020 — 16 Total subsidiaries 4,536 4,556 Total medium- and long-term debt $ 5,143 $ 5,160 (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 each FHLB advance resets every four weeks, based on the FHLB auction rate, with the reset date of each note scheduled at one-week intervals. At June 30, 2017 , the weighted-average rate on these advances was 1.13% . 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 June 30, 2017 , $15.6 billion of real estate-related loans were pledged to the FHLB as blanket collateral for current and potential future borrowings of approximately $3.5 billion . Unamortized debt issuance costs deducted from the carrying amount of medium- and long-term debt totaled $6 million at June 30, 2017 and $7 million at December 31, 2016 .

Accumulated Other Comprehensive

Accumulated Other Comprehensive Loss	6 Months Ended
	Jun. 30, 2017
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 six months ended June 30, 2017 and 2016 , including the amount of income tax expense (benefit) allocated to each component of other comprehensive income (loss). Six Months Ended June 30, (in millions) 2017 2016 Accumulated net unrealized (losses) gains on investment securities: Balance at beginning of period, net of tax $ (33 ) $ 9 Net unrealized holding gains arising during the period 21 191 Less: Provision for income taxes 8 70 Net unrealized holding gains arising during the period, net of tax 13 121 Less: Net losses realized as a yield adjustment in interest on investment securities (1 ) (2 ) Less: Benefit for income taxes — (1 ) Reclassification adjustment for net losses realized as a yield adjustment included in net income, net of tax (1 ) (1 ) Change in net unrealized gains on investment securities, net of tax 14 122 Balance at end of period, net of tax $ (19 ) $ 131 Accumulated defined benefit pension and other postretirement plans adjustment: Balance at beginning of period, net of tax $ (350 ) $ (438 ) Amortization of actuarial net loss 25 19 Amortization of prior service credit (13 ) — Amounts recognized in salaries and benefits expense 12 19 Less: Provision for income taxes 4 7 Change in defined benefit pension and other postretirement plans adjustment, net of tax 8 12 Balance at end of period, net of tax $ (342 ) $ (426 ) Total accumulated other comprehensive loss at end of period, net of tax $ (361 ) $ (295 )

Net Income Per Common Share

Net Income Per Common Share	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Net Income Per Common Share	NET INCOME PER COMMON SHARE Basic and diluted net income per common share are presented in the following table. Three Months Ended June 30, Six Months Ended June 30, (in millions, except per share data) 2017 2016 2017 2016 Basic and diluted Net income $ 203 $ 104 $ 405 $ 164 Less: Income allocated to participating securities 1 1 3 2 Net income attributable to common shares $ 202 $ 103 $ 402 $ 162 Basic average common shares 175 173 175 173 Basic net income per common share $ 1.15 $ 0.60 $ 2.30 $ 0.94 Basic average common shares 175 173 175 173 Dilutive common stock equivalents: Net effect of the assumed exercise of stock options 3 2 3 2 Net effect of the assumed exercise of warrants 1 2 2 2 Diluted average common shares 179 177 180 177 Diluted net income per common share $ 1.13 $ 0.58 $ 2.24 $ 0.92 The following average shares related to outstanding options to purchase shares of common stock were not included in the computation of diluted net income per common share because the options were anti-dilutive for the period. There were no anti-dilutive options for both the three- and six-month periods ended June 30, 2017 . (shares in millions) Three Months Ended June 30, 2016 Six Months Ended June 30, 2016 Average outstanding options 2.6 4.8 Range of exercise prices $46.68 - $59.86 $37.26 - $59.86

Employee Benefit Plans

Employee Benefit Plans	6 Months Ended
	Jun. 30, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]
Employee Benefit Plans	EMPLOYEE BENEFIT PLANS Net periodic benefit costs are charged to "employee benefits expense" on the consolidated statements of comprehensive income. The components of net periodic benefit cost 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 June 30, Six Months Ended June 30, (in millions) 2017 2016 2017 2016 Service cost $ 7 $ 8 $ 14 $ 16 Interest cost 19 23 39 46 Expected return on plan assets (39 ) (40 ) (79 ) (81 ) Amortization of prior service (credit) cost (4 ) 1 (9 ) 2 Amortization of net loss 10 8 21 16 Net periodic defined benefit credit $ (7 ) $ — $ (14 ) $ (1 ) Non-Qualified Defined Benefit Pension Plan Three Months Ended June 30, Six Months Ended June 30, (in millions) 2017 2016 2017 2016 Service cost $ — $ 1 $ 1 $ 2 Interest cost 2 3 4 5 Amortization of prior service credit (2 ) (1 ) (4 ) (2 ) Amortization of net loss 2 1 4 3 Net periodic defined benefit cost $ 2 $ 4 $ 5 $ 8 Postretirement Benefit Plan Three Months Ended June 30, Six Months Ended June 30, (in millions) 2017 2016 2017 2016 Interest cost $ — $ 1 $ 1 $ 2 Expected return on plan assets — (1 ) (1 ) (2 ) Net periodic postretirement benefit cost $ — $ — $ — $ — For further information on the Corporation's employee benefit plans, refer to note 17 to the consolidated financial statements in the Corporation's 2016 Annual Report.

Income Taxes And Tax-Related It

Income Taxes And Tax-Related Items	6 Months Ended
	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes and Tax-Related Items	INCOME TAXES AND TAX-RELATED ITEMS Net unrecognized tax benefits were $11 million at June 30, 2017 , compared to $15 million at December 31, 2016 . The decrease in unrecognized tax benefits of $4 million was primarily due to the recognition of federal settlements partially offset by an increase to established reserves. The Corporation anticipates it is reasonably possible the final settlement of federal and state tax issues will result in a decrease in net unrecognized tax benefits of $1 million within the next twelve months. Included in "accrued expense and other liabilities" on the consolidated balance sheets was a $9 million liability for tax-related interest and penalties at June 30, 2017 compared to $7 million at December 31, 2016 . Net deferred tax assets were $224 million at June 30, 2017 , compared to $217 million at December 31, 2016 . The increase of $7 million in net deferred tax assets resulted primarily from a decrease in deferred tax liabilities related to lease financing transactions, partially offset by decreases in unrealized losses on investment securities available-for-sale and deferred compensation. Included in deferred tax assets at both June 30, 2017 and December 31, 2016 were $4 million of state net operating loss carryforwards, which expire between 2017 and 2026 . The Corporation believes it is more likely than not 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 June 30, 2017 and December 31, 2016 . The determination regarding valuation allowance was based on evidence of loss carryback capacity, projected future reversals of existing taxable temporary differences to absorb the deferred tax assets and assumptions made regarding future events. 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 the 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	6 Months Ended
	Jun. 30, 2017
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, 2016 and Form 10-Q for the period ended March 31, 2017 , Comerica Bank, a wholly owned subsidiary of the Corporation, 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. A ruling is not expected for some time. Management believes that 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 that 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, consolidated results of operations or consolidated cash flows. Legal fees of $5 million were included in "other noninterest expenses" on the consolidated statements of income for each of the three-month periods ended June 30, 2017 and 2016 , and $10 million for each of the six-month periods ended June 30, 2017 and 2016 . 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 $28 million at June 30, 2017 . 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 that an estimate can currently be made. The Corporation’s estimate involves significant judgment, given the varying stages of the proceedings (including the fact that 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 that the ultimate resolution of these matters, if unfavorable, may be material to the Corporation's consolidated financial condition, consolidated results of operations or consolidated cash flows. For information regarding income tax contingencies, refer to note 11 .

Restructuring Charges

Restructuring Charges	6 Months Ended
	Jun. 30, 2017
Restructuring and Related Activities [Abstract]
Restructuring Charges	RESTRUCTURING CHARGES The Corporation approved and launched an initiative in the second quarter 2016 designed to reduce overhead and increase revenue (the GEAR Up initiative). The actions in the initiative include, but are not limited to, a reduction in workforce, a new retirement program, streamlining operational processes, real estate optimization including consolidating 38 banking centers as well as reducing office and operations space, selective outsourcing of technology functions and reduction of technology system applications. Certain actions associated with the GEAR Up initiative result in restructuring charges. Generally, costs associated with or incurred to generate revenue as part of the initiative are recorded according to the nature of the cost and are not included in restructuring charges. The Corporation considers the following costs associated with the initiative to be restructuring charges: • Employee costs: Primarily severance costs in accordance with the Corporation’s severance plan. • Facilities costs: Costs pertaining to consolidating banking centers and other facilities, such as lease termination costs and decommissioning costs. Also includes accelerated depreciation and impairment of owned property to be sold. • Technology costs: Impairment and other costs associated with optimizing technology infrastructure and reducing the number of applications. • Other costs: Includes primarily professional fees, as well as other contract termination fees and legal fees incurred in the execution of the initiative. Restructuring charges are recorded as a component of noninterest expenses on the consolidated statements of comprehensive income. The following table presents changes in restructuring reserves, cumulative charges incurred to date and total expected restructuring charges: (in millions) Employee Costs Facilities Costs Technology Costs Other Costs Total Three Months Ended June 30, 2017 Balance at beginning of period $ 7 $ — $ 3 $ 3 $ 13 Restructuring charges 3 4 6 1 14 Payments (4 ) (4 ) (4 ) (2 ) (14 ) Adjustments for non-cash charges (a) — — (2 ) — (2 ) Balance at end of period $ 6 $ — $ 3 $ 2 $ 11 Three Months Ended June 30, 2016 Balance at beginning of period $ — $ — $ — $ — $ — Restructuring charges 46 — — 7 53 Payments — — — (3 ) (3 ) Balance at end of period $ 46 $ — $ — $ 4 $ 50 Six Months Ended June 30, 2017 Balance at beginning of period $ 10 $ 4 $ — $ 4 $ 18 Restructuring charges 4 5 12 4 25 Payments (8 ) (9 ) (4 ) (6 ) (27 ) Adjustments for non-cash charges (a) — — (5 ) — (5 ) Balance at end of period $ 6 $ — $ 3 $ 2 $ 11 Six Months Ended June 30, 2016 Balance at beginning of period $ — $ — $ — $ — $ — Restructuring charges 46 — — 7 53 Payments — — — (3 ) (3 ) Balance at end of period $ 46 $ — $ — $ 4 $ 50 Total restructuring charges incurred to date $ 56 $ 20 $ 12 $ 30 $ 118 Total expected restructuring charges (b) 56 30 - 35 20 - 35 34 140 - 160 (a) Adjustments for non-cash charges primarily include impairments of previously capitalized software costs. (b) Restructuring activities are expected to be substantially completed by 12/31/2018 . Restructuring charges directly attributable to a business segment are assigned to that business segment. Restructuring charges incurred by areas whose services support the overall Corporation are allocated based on the methodology described in note 23 to the consolidated financial statements in the Corporation's 2016 Annual Report. Total restructuring charges assigned to the Business Bank, Retail Bank and Wealth Management were $7 million , $4 million and $3 million , respectively, for the three months ended June 30, 2017 and $13 million , $8 million and $4 million , respectively, for the six months ended June 30, 2017 . Total restructuring charges assigned to the Business Bank, Retail Bank and Wealth Management were $26 million , $19 million and $8 million , respectively, for both the three- and six-month periods ended June 30, 2016 . Remaining expected restructuring charges will be assigned to the business segments using the same methodology. Facilities costs pertaining to the consolidation of banking centers primarily impacted the Retail Bank.

Business Segment Information

Business Segment Information	6 Months Ended
	Jun. 30, 2017
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 June 30, 2017 . 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 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 small business banking and personal financial services, consisting of consumer lending, consumer deposit gathering and mortgage loan origination. In addition to a full range of financial services provided to small business customers, 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 discontinued operations, 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 2016 Annual Report. Business segment financial results are as follows: (dollar amounts in millions) Business Retail Wealth Management Finance Other Total Three Months Ended June 30, 2017 Earnings summary: Net interest income (expense) $ 336 $ 162 $ 42 $ (49 ) $ 9 $ 500 Provision for credit losses 12 5 (2 ) — 2 17 Noninterest income 152 48 64 10 2 276 Noninterest expenses 196 180 71 (1 ) 11 457 Provision (benefit) for income taxes 100 9 14 (17 ) (7 ) (a) 99 Net income (loss) $ 180 $ 16 $ 23 $ (21 ) $ 5 $ 203 Net credit-related charge-offs (recoveries) $ 10 $ 9 $ (1 ) $ — $ — $ 18 Selected average balances: Assets $ 38,853 $ 6,487 $ 5,432 $ 13,936 $ 6,610 $ 71,318 Loans 37,580 5,865 5,278 — — 48,723 Deposits 28,748 23,935 4,106 156 183 57,128 Statistical data: Return on average assets (b) 1.85 % 0.27 % 1.76 % N/M N/M 1.14 % Efficiency ratio (c) 40.19 84.79 66.44 N/M N/M 58.63 (dollar amounts in millions) Business Retail Wealth Management Finance Other Total Three Months Ended June 30, 2016 Earnings summary: Net interest income (expense) $ 349 $ 154 $ 42 $ (105 ) $ 5 $ 445 Provision for credit losses 46 1 3 — (1 ) 49 Noninterest income 143 48 62 10 5 268 Noninterest expenses 221 205 81 — 11 518 Provision (benefit) for income taxes 74 (2 ) 7 (36 ) (1 ) 42 Net income (loss) $ 151 $ (2 ) $ 13 $ (59 ) $ 1 $ 104 Net credit-related charge-offs $ 42 $ 1 $ 4 $ — $ — $ 47 Selected average balances: Assets $ 39,983 $ 6,558 $ 5,215 $ 13,927 $ 4,985 $ 70,668 Loans 38,574 5,879 5,016 — — 49,469 Deposits 28,441 23,546 4,213 50 271 56,521 Statistical data: Return on average assets (b) 1.52 % (0.04 )% 0.99 % N/M N/M 0.59 % Efficiency ratio (c) 44.75 101.58 78.22 N/M N/M 72.43 (a) Includes tax benefit of $5 million from employee stock transactions. (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 (fully taxable equivalent basis) and noninterest income excluding net securities gains (losses). N/M – not meaningful (dollar amounts in millions) Business Retail Wealth Management Finance Other Total Six Months Ended June 30, 2017 Earnings summary: Net interest income (expense) $ 668 $ 322 $ 83 $ (120 ) $ 17 $ 970 Provision for credit losses 22 17 (3 ) — (3 ) 33 Noninterest income 296 96 128 21 6 547 Noninterest expenses 393 359 141 (2 ) 23 914 Provision (benefit) for income taxes 192 15 27 (41 ) (28 ) (a) 165 Net income (loss) $ 357 $ 27 $ 46 $ (56 ) $ 31 $ 405 Net credit-related charge-offs (recoveries) $ 40 $ 14 $ (3 ) $ — $ — $ 51 Selected average balances: Assets $ 38,474 $ 6,506 $ 5,419 $ 13,940 $ 7,228 $ 71,567 Loans 37,169 5,880 5,264 — — 48,313 Deposits 29,196 23,866 4,042 149 199 57,452 Statistical data: Return on average assets (b) 1.87 % 0.22 % 1.73 % N/M N/M 1.14 % Efficiency ratio (c) 40.75 85.39 66.81 N/M N/M 60.10 (dollar amounts in millions) Business Retail Wealth Management Finance Other Total Six Months Ended June 30, 2016 Earnings summary: Net interest income (expense) $ 706 $ 309 $ 85 $ (218 ) $ 10 $ 892 Provision for credit losses 197 4 (2 ) — (2 ) 197 Noninterest income 279 92 120 21 — 512 Noninterest expenses 427 385 154 (1 ) 11 976 Provision (benefit) for income taxes 118 3 19 (74 ) 1 67 Net income (loss) $ 243 $ 9 $ 34 $ (122 ) $ — $ 164 Net credit-related charge-offs $ 99 $ 3 $ 3 $ — $ — $ 105 Selected average balances: Assets $ 39,574 $ 6,551 $ 5,189 $ 13,858 $ 4,776 $ 69,948 Loans 38,068 5,873 4,990 — — 48,931 Deposits 28,778 23,328 4,192 73 244 56,615 Statistical data: Return on average assets (b) 1.24 % 0.07 % 1.32 % N/M N/M 0.47 % Efficiency ratio (c) 43.28 95.42 75.15 N/M N/M 69.25 (a) Includes tax benefit of $29 million from employee stock transactions. (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 (fully taxable equivalent basis) and noninterest income excluding net securities gains. 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 June 30, 2017 . 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: (dollar amounts in millions) Michigan California Texas Other Finance Total Three Months Ended June 30, 2017 Earnings summary: Net interest income (expense) $ 167 $ 178 $ 113 $ 82 $ (40 ) $ 500 Provision for credit losses (2 ) 24 (15 ) 8 2 17 Noninterest income 81 45 33 105 12 276 Noninterest expenses 145 98 94 110 10 457 Provision (benefit) for income taxes 38 40 25 20 (24 ) (a) 99 Net income (loss) $ 67 $ 61 $ 42 $ 49 $ (16 ) $ 203 Net credit-related charge-offs (recoveries) $ (1 ) $ 8 $ 5 $ 6 $ — $ 18 Selected average balances: Assets $ 13,371 $ 18,446 $ 10,481 $ 8,474 $ 20,546 $ 71,318 Loans 12,712 18,194 10,015 7,802 — 48,723 Deposits 21,698 17,344 9,632 8,115 339 57,128 Statistical data: Return on average assets (b) 1.20 % 1.33 % 1.52 % 2.24 % N/M 1.14 % Efficiency ratio (c) 58.14 43.82 64.37 58.45 N/M 58.63 (dollar amounts in millions) Michigan California Texas Other Finance Total Three Months Ended June 30, 2016 Earnings summary: Net interest income (expense) $ 164 $ 176 $ 117 $ 88 $ (100 ) $ 445 Provision for credit losses 3 18 32 (3 ) (1 ) 49 Noninterest income 81 38 32 102 15 268 Noninterest expenses 159 120 113 115 11 518 Provision (benefit) for income taxes 28 27 2 22 (37 ) 42 Net income (loss) $ 55 $ 49 $ 2 $ 56 $ (58 ) $ 104 Net credit-related charge-offs (recoveries) $ — $ 17 $ 31 $ (1 ) $ — $ 47 Selected average balances: Assets $ 13,142 $ 18,155 $ 11,287 $ 9,172 $ 18,912 $ 70,668 Loans 12,502 17,865 10,841 8,261 — 49,469 Deposits 21,519 16,967 10,052 7,662 321 56,521 Statistical data: Return on average assets (b) 1.00 % 1.08 % 0.07 % 2.45 % N/M 0.59 % Efficiency ratio (c) 64.65 55.73 75.89 60.77 N/M 72.43 (a) Includes tax benefit of $5 million from employee stock transactions. (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 (fully taxable equivalent basis) and noninterest income excluding net securities gains. N/M – not meaningful (dollar amounts in millions) Michigan California Texas Other Finance Total Six Months Ended June 30, 2017 Earnings summary: Net interest income (expense) $ 337 $ 349 $ 226 $ 161 $ (103 ) $ 970 Provision for credit losses (4 ) 45 (24 ) 19 (3 ) 33 Noninterest income 164 86 65 205 27 547 Noninterest expenses 295 194 188 216 21 914 Provision (benefit) for income taxes 75 76 47 36 (69 ) (a) 165 Net income (loss) $ 135 $ 120 $ 80 $ 95 $ (25 ) $ 405 Net credit-related charge-offs (recoveries) $ (4 ) $ 18 $ 27 $ 10 $ — $ 51 Selected average balances: Assets $ 13,313 $ 18,203 $ 10,518 $ 8,365 $ 21,168 $ 71,567 Loans 12,650 17,938 10,062 7,663 — 48,313 Deposits 21,923 17,294 9,871 8,016 348 57,452 Statistical data: Return on average assets (b) 1.20 % 1.33 % 1.44 % 2.19 % N/M 1.14 % Efficiency ratio (c) 58.75 44.50 64.58 58.87 N/M 60.10 (dollar amounts in millions) Michigan California Texas Other Finance Total Six Months Ended June 30, 2016 Earnings summary: Net interest income (expense) $ 338 $ 351 $ 238 $ 173 $ (208 ) $ 892 Provision for credit losses (3 ) 12 201 (11 ) (2 ) 197 Noninterest income 157 76 62 196 21 512 Noninterest expenses 310 224 213 219 10 976 Provision (benefit) for income taxes 63 70 (39 ) 46 (73 ) 67 Net income (loss) $ 125 $ 121 $ (75 ) $ 115 $ (122 ) $ 164 Net credit-related charge-offs (recoveries) $ 5 $ 25 $ 78 $ (3 ) $ — $ 105 Selected average balances: Assets $ 13,194 $ 17,926 $ 11,291 $ 8,903 $ 18,634 $ 69,948 Loans 12,560 17,653 10,802 7,916 — 48,931 Deposits 21,594 16,823 10,214 7,667 317 56,615 Statistical data: Return on average assets (b) 1.12 % 1.36 % (1.28 )% 2.60 % N/M 0.47 % Efficiency ratio (c) 62.31 52.11 70.95 59.45 N/M 69.25 (a) Includes tax benefit of $29 million from employee stock transactions. (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 (fully taxable equivalent basis) and noninterest income excluding net securities gains. N/M – not meaningful

Basis of Presentation and Acc22

Basis of Presentation and Accounting Policies Basis of Presentation and Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2017
Accounting Policies [Abstract]
Share-Based Compensation	Share-Based Compensation Effective January 1, 2016, the Corporation adopted the provisions of Financial Accounting Standards Board (FASB) Accounting Standards Update (ASU) No. 2016-09, “Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payments Accounting” (ASU 2016-09). ASU 2016-09 provides for the election of an accounting policy as to the timing of when stock award forfeitures are recognized in compensation expense. The Corporation elected to account for forfeitures as they occur, rather than account for compensation cost based on an estimate of the number of awards that are expected to vest. The prior period effect of this policy election as of the beginning of the year was reported as "cumulative effect of change in accounting principle" in the accompanying Consolidated Statements of Changes in Shareholders’ Equity (unaudited). In addition, ASU 2016-09 requires excess tax benefits and deficiencies resulting from employee stock awards to be prospectively recognized as a component of income taxes. Previously, excess tax benefits and deficiencies were recognized in "capital surplus" in the Consolidated Statements of Changes in Shareholders' Equity. Net excess tax benefits for awards that vested, were exercised or expired included in the "provision for income taxes" totaled $5 million and $ 29 million for the three- and six-month periods ended June 30, 2017 , respectively. The Corporation also retrospectively adopted certain changes to the statement of cash flows in accordance with ASU 2016-09. Excess tax benefits must be classified as an operating activity, and cash paid to a tax authority by the Corporation when withholding shares from an employee’s award for tax-withholding purposes must be classified as a financing activity. Accordingly, the Corporation reclassified $4 million from operating activities to financing activities in the Consolidated Statements of Cash Flows (unaudited) pertaining to shares withheld from employee awards for tax withholding purposes for the six months ended June 30, 2016 .
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In March 2017, the FASB issued ASU No. 2017-07, “Compensation - Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost” (ASU 2017-07), which requires employers to report service cost as part of compensation expense and the other components of net benefit cost separately from service cost on the statement of income. ASU 2017-07 is effective for the Corporation on January 1, 2018. Early adoption is permitted. The Corporation does not expect the new guidance to have a material impact on its financial condition or results of operation.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2017
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 June 30, 2017 and December 31, 2016 . (in millions) Total Level 1 Level 2 Level 3 June 30, 2017 Trading securities: Deferred compensation plan assets $ 88 $ 88 $ — $ — Investment securities available-for-sale: U.S. Treasury and other U.S. government agency securities 2,773 2,773 — — Residential mortgage-backed securities (a) 8,057 — 8,057 — State and municipal securities 5 — — 5 (b) Equity and other non-debt securities 109 63 — 46 (b) Total investment securities available-for-sale 10,944 2,836 8,057 51 Derivative assets: Interest rate contracts 96 — 83 13 Energy derivative contracts 104 — 104 — Foreign exchange contracts 36 — 36 — Warrants 2 — — 2 Total derivative assets 238 — 223 15 Total assets at fair value $ 11,270 $ 2,924 $ 8,280 $ 66 Derivative liabilities: Interest rate contracts $ 47 $ — $ 47 $ — Energy derivative contracts 102 — 102 — Foreign exchange contracts 34 — 34 — Total derivative liabilities 183 — 183 — Deferred compensation plan liabilities 88 88 — — Total liabilities at fair value $ 271 $ 88 $ 183 $ — (a) Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises. (b) Auction-rate securities. (in millions) Total Level 1 Level 2 Level 3 December 31, 2016 Trading securities: Deferred compensation plan assets $ 87 $ 87 $ — $ — Equity and other non-debt securities 1 1 — — Total trading securities 88 88 — — Investment securities available-for-sale: U.S. Treasury and other U.S. government agency securities 2,779 2,779 — — Residential mortgage-backed securities (a) 7,872 — 7,872 — State and municipal securities 7 — — 7 (b) Equity and other non-debt securities 129 82 — 47 (b) Total investment securities available-for-sale 10,787 2,861 7,872 54 Derivative assets: Interest rate contracts 223 — 212 11 Energy derivative contracts 146 — 146 — Foreign exchange contracts 38 — 38 — Warrants 3 — — 3 Total derivative assets 410 — 396 14 Total assets at fair value $ 11,285 $ 2,949 $ 8,268 $ 68 Derivative liabilities: Interest rate contracts $ 81 $ — $ 81 $ — Energy derivative contracts 144 — 144 — Foreign exchange contracts 29 — 29 — Total derivative liabilities 254 — 254 — Deferred compensation plan liabilities 87 87 — — Total liabilities at fair value $ 341 $ 87 $ 254 $ — (a) Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises. (b) Auction-rate securities.
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 six-month periods ended June 30, 2017 and 2016 . Net Realized/Unrealized Gains (Losses) (Pretax) Balance at Beginning of Period Recorded in Earnings Recorded in Other Comprehensive Income Balance at End of Period (in millions) Realized Unrealized Redemptions Sales Three Months Ended June 30, 2017 Investment securities available-for-sale: State and municipal securities (a) $ 5 $ — $ — $ — $ — $ — $ 5 Equity and other non-debt securities (a) 46 — — — — — 46 Total investment securities available-for-sale 51 — — — — — 51 Derivative assets: Interest rate contracts 11 — 2 (b) — — — 13 Warrants 2 4 (b) — — — (4 ) 2 Three Months Ended June 30, 2016 Investment securities available-for-sale: State and municipal securities (a) $ 9 $ — $ — $ — $ (1 ) $ — $ 8 Corporate debt securities (a) 1 — — — — — 1 Equity and other non-debt securities (a) 51 — — (3 ) — — 48 Total investment securities available-for-sale 61 — — (3 ) (1 ) — 57 Derivative assets: Interest rate contracts 20 — 7 (b) — — — 27 Warrants 2 — 1 (b) — — (1 ) 2 Six Months Ended June 30, 2017 Investment securities available-for-sale: State and municipal securities (a) $ 7 $ — $ — $ — $ (2 ) $ — $ 5 Equity and other non-debt securities (a) 47 — — — (1 ) — 46 Total investment securities available-for-sale 54 — — — (3 ) — 51 Derivative assets: Interest rate contracts 11 — 2 (b) — — — 13 Warrants 3 5 (b) (1 ) (b) — — (5 ) 2 Six Months Ended June 30, 2016 Investment securities available-for-sale: State and municipal securities (a) $ 9 $ — $ — $ — $ (1 ) $ — $ 8 Corporate debt securities (a) 1 — — — — — 1 Equity and other non-debt securities (a) 67 — — (4 ) (15 ) — 48 Total investment securities available-for-sale 77 — — (4 ) (16 ) — 57 Derivative assets: Interest rate contracts 9 — 18 (b) — — — 27 Warrants 2 — 1 (b) — — (1 ) 2 (a) Auction-rate securities. (b) Realized and unrealized gains and losses due to changes in fair value recorded in "other noninterest income" on the consolidated statements of comprehensive income.
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 June 30, 2017 and December 31, 2016 . No liabilities were recorded at fair value on a nonrecurring basis at June 30, 2017 and December 31, 2016 . (in millions) Level 3 June 30, 2017 Loans: Commercial $ 248 Commercial mortgage 18 International 5 Total loans 271 Other real estate 13 Total assets at fair value $ 284 December 31, 2016 Loans: Commercial $ 256 Commercial mortgage 15 International 11 Total loans 282 Other real estate 1 Total assets at fair value $ 283
Quantitative Information About Level 3 Measurements	The Corporation's Level 3 recurring fair value measurements primarily include auction-rate securities where fair value is determined using an income approach based on a discounted cash flow model and certain interest rate derivative contracts where credit valuation adjustments are significant to the overall fair value of the derivative. The inputs in the table below reflect management's expectation of continued illiquidity in the secondary auction-rate securities market due to a lack of market activity for the issuers remaining in the portfolio, a lack of market incentives for issuer redemptions, and the expectation for a continuing low interest rate environment. The workout periods reflect management's expectation of the pace at which short-term interest rates could rise at each respective period. Discounted Cash Flow Model Unobservable Input Fair Value (in millions) Discount Rate Workout Period (in years) June 30, 2017 State and municipal securities (a) $ 5 5% - 7% 1 - 2 Equity and other non-debt securities (a) 46 7% - 9% 1 - 2 December 31, 2016 State and municipal securities (a) $ 7 4% - 6% 1 - 2 Equity and other non-debt securities (a) 47 7% - 9% 1 - 2 (a) Auction-rate securities.
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 June 30, 2017 Assets Cash and due from banks $ 1,372 $ 1,372 $ 1,372 $ — $ — Interest-bearing deposits with banks 4,259 4,259 4,259 — — Investment securities held-to-maturity 1,430 1,424 — 1,424 — Loans held-for-sale 1 1 — 1 — Total loans, net of allowance for loan losses (a) 48,703 48,468 — — 48,468 Customers’ liability on acceptances outstanding 3 3 3 — — Restricted equity investments 228 228 228 — — Nonmarketable equity securities (b) 6 10 Liabilities Demand deposits (noninterest-bearing) 31,210 31,210 — 31,210 — Interest-bearing deposits 23,133 23,133 — 23,133 — Customer certificates of deposit 2,438 2,418 — 2,418 — Total deposits 56,781 56,761 — 56,761 — Short-term borrowings 541 541 541 — — Acceptances outstanding 3 3 3 — — Medium- and long-term debt 5,143 5,138 — 5,138 — Credit-related financial instruments (76 ) (76 ) — — (76 ) December 31, 2016 Assets Cash and due from banks $ 1,249 $ 1,249 $ 1,249 $ — $ — Interest-bearing deposits with banks 5,969 5,969 5,969 — — Investment securities held-to-maturity 1,582 1,576 — 1,576 — Loans held-for-sale 4 4 — 4 — Total loans, net of allowance for loan losses (a) 48,358 48,250 — — 48,250 Customers’ liability on acceptances outstanding 5 5 5 — — Restricted equity investments 207 207 207 — — Nonmarketable equity securities (b) 11 16 Liabilities Demand deposits (noninterest-bearing) 31,540 31,540 — 31,540 — Interest-bearing deposits 24,639 24,639 — 24,639 — Customer certificates of deposit 2,806 2,731 — 2,731 — Total deposits 58,985 58,910 — 58,910 — Short-term borrowings 25 25 25 — — Acceptances outstanding 5 5 5 — — Medium- and long-term debt 5,160 5,132 — 5,132 — Credit-related financial instruments (73 ) (73 ) — — (73 ) (a) Included $271 million and $282 million of impaired loans recorded at fair value on a nonrecurring basis at June 30, 2017 and December 31, 2016 , 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)	6 Months Ended
	Jun. 30, 2017
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 June 30, 2017 Investment securities available-for-sale: U.S. Treasury and other U.S. government agency securities $ 2,762 $ 11 $ — $ 2,773 Residential mortgage-backed securities (a) 8,089 45 77 8,057 State and municipal securities 5 — — 5 Equity and other non-debt securities 109 1 1 109 Total investment securities available-for-sale (b) $ 10,965 $ 57 $ 78 $ 10,944 Investment securities held-to-maturity (c): Residential mortgage-backed securities (a) $ 1,430 $ 1 $ 7 $ 1,424 December 31, 2016 Investment securities available-for-sale: U.S. Treasury and other U.S. government agency securities $ 2,772 $ 8 $ 1 $ 2,779 Residential mortgage-backed securities (a) 7,921 48 97 7,872 State and municipal securities 7 — — 7 Equity and other non-debt securities 129 1 1 129 Total investment securities available-for-sale (b) $ 10,829 $ 57 $ 99 $ 10,787 Investment securities held-to-maturity (c): Residential mortgage-backed securities (a) $ 1,582 $ 1 $ 7 $ 1,576 (a) Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises. (b) Included auction-rate securities at amortized cost and fair value of $52 million and $51 million , respectively as of June 30, 2017 and $55 million and $54 million , respectively, as of December 31, 2016 . (c) The amortized cost of investment securities held-to-maturity included net unrealized losses of $11 million at June 30, 2017 and $12 million at December 31, 2016 related to securities transferred from available-for-sale, which are included in accumulated other comprehensive loss.
Summary Of Investment Securities In Unrealized Loss Positions	A summary of the Corporation’s investment securities in an unrealized loss position as of June 30, 2017 and December 31, 2016 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 June 30, 2017 U.S. Treasury and other U.S. government agency securities $ 301 $ — (c) $ — $ — $ 301 $ — (c) Residential mortgage-backed securities (a) 4,667 69 1,073 27 5,740 96 State and municipal securities (b) — — 5 — (c) 5 — (c) Equity and other non-debt securities (b) — — 46 1 46 1 Total temporarily impaired securities $ 4,968 $ 69 $ 1,124 $ 28 $ 6,092 $ 97 December 31, 2016 U.S. Treasury and other U.S. government agency securities $ 527 $ 1 $ — $ — $ 527 $ 1 Residential mortgage-backed securities (a) 4,992 87 1,177 32 6,169 119 State and municipal securities (b) — — 7 — (c) 7 — (c) Equity and other non-debt securities (b) 36 — (c) 11 — (c) 47 — (c) Total temporarily impaired securities $ 5,555 $ 88 $ 1,195 $ 32 $ 6,750 $ 120 (a) Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises. (b) Primarily auction-rate securities. (c) Unrealized losses less than $0.5 million.
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 gains (losses)” on the consolidated statements of comprehensive income, computed based on the adjusted cost of the specific security. Three Months Ended June 30, Six Months Ended June 30, (in millions) 2017 2016 2017 2016 Securities gains $ — $ — $ 1 $ — Securities losses (a) (2 ) (1 ) (3 ) (3 ) Net securities losses $ (2 ) $ (1 ) $ (2 ) $ (3 ) (a) Primarily charges related to a derivative contract tied to the conversion rate of Visa Class B shares.
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) Available-for-sale Held-to-maturity June 30, 2017 Amortized Cost Fair Value Amortized Cost Fair Value Contractual maturity Within one year $ 20 $ 20 $ — $ — After one year through five years 2,991 3,002 — — After five years through ten years 1,833 1,861 21 20 After ten years 6,012 5,952 1,409 1,404 Subtotal 10,856 10,835 1,430 1,424 Equity and other non-debt securities 109 109 — — Total investment securities $ 10,965 $ 10,944 $ 1,430 $ 1,424

Credit Quality And Allowance 25

Credit Quality And Allowance For Credit Losses (Tables)	6 Months Ended
	Jun. 30, 2017
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 June 30, 2017 Business loans: Commercial $ 38 $ 11 $ 23 $ 72 $ 379 $ 30,998 $ 31,449 Real estate construction: Commercial Real Estate business line (a) — — — — — 2,560 2,560 Other business lines (b) — 1 — 1 — 296 297 Total real estate construction — 1 — 1 — 2,856 2,857 Commercial mortgage: Commercial Real Estate business line (a) 16 — — 16 9 1,801 1,826 Other business lines (b) 2 3 7 12 32 7,104 7,148 Total commercial mortgage 18 3 7 28 41 8,905 8,974 Lease financing — — — — 8 464 472 International 8 — — 8 6 1,131 1,145 Total business loans 64 15 30 109 434 44,354 44,897 Retail loans: Residential mortgage 8 10 — 18 36 1,922 1,976 Consumer: Home equity 6 2 — 8 23 1,765 1,796 Other consumer 1 — — 1 — 738 739 Total consumer 7 2 — 9 23 2,503 2,535 Total retail loans 15 12 — 27 59 4,425 4,511 Total loans $ 79 $ 27 $ 30 $ 136 $ 493 $ 48,779 $ 49,408 December 31, 2016 Business loans: Commercial $ 30 $ 12 $ 14 $ 56 $ 445 $ 30,493 $ 30,994 Real estate construction: Commercial Real Estate business line (a) — — — — — 2,485 2,485 Other business lines (b) — — — — — 384 384 Total real estate construction — — — — — 2,869 2,869 Commercial mortgage: Commercial Real Estate business line (a) 5 — — 5 9 2,004 2,018 Other business lines (b) 58 5 5 68 37 6,808 6,913 Total commercial mortgage 63 5 5 73 46 8,812 8,931 Lease financing — — — — 6 566 572 International 1 — — 1 14 1,243 1,258 Total business loans 94 17 19 130 511 43,983 44,624 Retail loans: Residential mortgage 7 3 — 10 39 1,893 1,942 Consumer: Home equity 4 3 — 7 28 1,765 1,800 Other consumer 1 — — 1 4 717 722 Total consumer 5 3 — 8 32 2,482 2,522 Total retail loans 12 6 — 18 71 4,375 4,464 Total loans $ 106 $ 23 $ 19 $ 148 $ 582 $ 48,358 $ 49,088 (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 June 30, 2017 Business loans: Commercial $ 29,492 $ 661 $ 917 $ 379 $ 31,449 Real estate construction: Commercial Real Estate business line (e) 2,545 15 — — 2,560 Other business lines (f) 297 — — — 297 Total real estate construction 2,842 15 — — 2,857 Commercial mortgage: Commercial Real Estate business line (e) 1,744 66 7 9 1,826 Other business lines (f) 6,894 110 112 32 7,148 Total commercial mortgage 8,638 176 119 41 8,974 Lease financing 443 20 1 8 472 International 1,064 57 18 6 1,145 Total business loans 42,479 929 1,055 434 44,897 Retail loans: Residential mortgage 1,930 10 — 36 1,976 Consumer: Home equity 1,769 1 3 23 1,796 Other consumer 738 1 — — 739 Total consumer 2,507 2 3 23 2,535 Total retail loans 4,437 12 3 59 4,511 Total loans $ 46,916 $ 941 $ 1,058 $ 493 $ 49,408 December 31, 2016 Business loans: Commercial $ 28,616 $ 944 $ 989 $ 445 $ 30,994 Real estate construction: Commercial Real Estate business line (e) 2,485 — — — 2,485 Other business lines (f) 381 — 3 — 384 Total real estate construction 2,866 — 3 — 2,869 Commercial mortgage: Commercial Real Estate business line (e) 1,970 19 20 9 2,018 Other business lines (f) 6,645 109 122 37 6,913 Total commercial mortgage 8,615 128 142 46 8,931 Lease financing 550 11 5 6 572 International 1,200 22 22 14 1,258 Total business loans 41,847 1,105 1,161 511 44,624 Retail loans: Residential mortgage 1,900 3 — 39 1,942 Consumer: Home equity 1,767 1 4 28 1,800 Other consumer 718 — — 4 722 Total consumer 2,485 1 4 32 2,522 Total retail loans 4,385 4 4 71 4,464 Total loans $ 46,232 $ 1,109 $ 1,165 $ 582 $ 49,088 (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. (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 page F-56 in the Corporation's 2016 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) June 30, 2017 December 31, 2016 Nonaccrual loans $ 493 $ 582 Reduced-rate loans (a) 8 8 Total nonperforming loans 501 590 Foreclosed property (b) 18 17 Total nonperforming assets $ 519 $ 607 (a) There were no reduced-rate business loans at both June 30, 2017 and December 31, 2016 . Reduced-rate retail loans were $8 million at both June 30, 2017 and December 31, 2016 . (b) Included $4 million and $3 million of foreclosed residential real estate properties at June 30, 2017 and December 31, 2016 , respectively.
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. 2017 2016 (in millions) Business Loans Retail Loans Total Business Loans Retail Loans Total Three Months Ended June 30 Allowance for loan losses: Balance at beginning of period $ 661 $ 47 $ 708 $ 674 $ 50 $ 724 Loan charge-offs (37 ) (2 ) (39 ) (52 ) (2 ) (54 ) Recoveries on loans previously charged-off 20 1 21 11 1 12 Net loan charge-offs (17 ) (1 ) (18 ) (41 ) (1 ) (42 ) Provision for loan losses 17 (2 ) 15 49 (2 ) 47 Balance at end of period $ 661 $ 44 $ 705 $ 682 $ 47 $ 729 Six Months Ended June 30 Allowance for loan losses: Balance at beginning of period $ 682 $ 48 $ 730 $ 579 $ 55 $ 634 Loan charge-offs (79 ) (4 ) (83 ) (127 ) (4 ) (131 ) Recoveries on loans previously charged-off 29 3 32 35 2 37 Net loan charge-offs (50 ) (1 ) (51 ) (92 ) (2 ) (94 ) Provision for loan losses 29 (3 ) 26 194 (6 ) 188 Foreign currency translation adjustment — — — 1 — 1 Balance at end of period $ 661 $ 44 $ 705 $ 682 $ 47 $ 729 As a percentage of total loans 1.47 % 0.98 % 1.43 % 1.48 % 1.07 % 1.45 % June 30 Allowance for loan losses: Individually evaluated for impairment $ 93 $ 1 $ 94 $ 112 $ — $ 112 Collectively evaluated for impairment 568 43 611 570 47 617 Total allowance for loan losses $ 661 $ 44 $ 705 $ 682 $ 47 $ 729 Loans: Individually evaluated for impairment $ 509 $ 41 $ 550 $ 646 $ 26 $ 672 Collectively evaluated for impairment 44,388 4,470 48,858 45,354 4,354 49,708 Total loans evaluated for impairment $ 44,897 $ 4,511 $ 49,408 $ 46,000 $ 4,380 $ 50,380
Changes In the Allowance For Credit Losses On Lending-Related Commitments	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 June 30, Six Months Ended June 30, (in millions) 2017 2016 2017 2016 Balance at beginning of period $ 46 $ 46 $ 41 $ 45 Charge-offs on lending-related commitments (a) — (5 ) — (11 ) Provision for credit losses on lending-related commitments 2 2 7 9 Balance at end of period $ 48 $ 43 $ 48 $ 43 (a) Charge-offs result from the sale of unfunded lending-related commitments.
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 June 30, 2017 Business loans: Commercial $ 115 $ 347 $ 462 $ 569 $ 87 Commercial mortgage: Commercial Real Estate business line (a) — 7 7 15 4 Other business lines (b) 1 33 34 40 1 Total commercial mortgage 1 40 41 55 5 International — 6 6 14 1 Total business loans 116 393 509 638 93 Retail loans: Residential mortgage 19 8 27 28 1 Consumer: Home equity 12 — 12 13 — Other consumer 2 — 2 2 — Total consumer 14 — 14 15 — Total retail loans (c) 33 8 41 43 1 Total individually evaluated impaired loans $ 149 $ 401 $ 550 $ 681 $ 94 December 31, 2016 Business loans: Commercial $ 90 $ 423 $ 513 $ 608 $ 80 Commercial mortgage: Commercial Real Estate business line (a) — 7 7 15 1 Other business lines (b) 2 30 32 40 3 Total commercial mortgage 2 37 39 55 4 International 3 11 14 20 2 Total business loans 95 471 566 683 86 Retail loans: Residential mortgage 19 9 28 30 2 Consumer: Home equity 15 — 15 19 — Other consumer 2 3 5 6 1 Total consumer 17 3 20 25 1 Total retail loans (c) 36 12 48 55 3 Total individually evaluated impaired loans $ 131 $ 483 $ 614 $ 738 $ 89 (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. Interest income recognized for the period primarily related to performing restructured loans. Individually Evaluated Impaired Loans 2017 2016 (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 June 30 Business loans: Commercial $ 473 $ 2 $ 639 $ 2 Commercial mortgage: Commercial Real Estate business line (a) 7 — 8 — Other business lines (b) 35 — 31 — Total commercial mortgage 42 — 39 — International 7 — 23 — Total business loans 522 2 701 2 Retail loans: Residential mortgage 27 — 11 — Consumer loans: Home equity 12 — 11 — Other consumer 2 — 3 — Total consumer 14 — 14 — Total retail loans 41 — 25 — Total individually evaluated impaired loans $ 563 $ 2 $ 726 $ 2 Six Months Ended June 30 Business loans: Commercial $ 487 $ 4 $ 537 $ 6 Commercial mortgage: Commercial Real Estate business line (a) 7 — 10 — Other business lines (b) 34 — 32 — Total commercial mortgage 41 — 42 — International 9 — 19 — Total business loans 537 4 598 6 Retail loans: Residential mortgage 27 — 12 — Consumer: Home equity 13 — 12 — Other consumer 3 — 4 — Total consumer 16 — 16 — Total retail loans 43 — 28 — Total individually evaluated impaired loans $ 580 $ 4 $ 626 $ 6 (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 tables detail the recorded balance at June 30, 2017 and 2016 of loans considered to be troubled debt restructurings (TDRs) that were restructured during the three- and six-month periods ended June 30, 2017 and 2016 , 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. 2017 2016 Type of Modification Type of Modification (in millions) Principal Deferrals (a) Interest Rate Reductions AB Note Restructures (b) Total Modifications Principal Deferrals (a) Interest Rate Reductions AB Note Restructures (b) Total Modifications Three Months Ended June 30 Business loans: Commercial $ 47 $ — $ 36 $ 83 $ 18 $ — $ 20 $ 38 Commercial mortgage: Other business lines (c) 1 — — 1 1 — — 1 Total business loans 48 — 36 84 19 — 20 39 Retail loans: Consumer: Home equity (d) — 1 — 1 1 — — 1 Total retail loans — 1 — 1 1 — — 1 Total loans $ 48 $ 1 $ 36 $ 85 $ 20 $ — $ 20 $ 40 Six Months Ended June 30 Business loans: Commercial $ 96 $ — $ 36 $ 132 $ 107 $ — $ 26 $ 133 Commercial mortgage: Other business lines (c) 4 — — 4 2 — — 2 International — — — — — — 10 10 Total business loans 100 — 36 136 109 — 36 145 Retail loans: Residential mortgage — — — — — 2 — 2 Consumer: Home equity (d) 1 2 — 3 1 — — 1 Total retail loans 1 2 — 3 1 2 — 3 Total loans $ 101 $ 2 $ 36 $ 139 $ 110 $ 2 $ 36 $ 148 (a) Primarily represents loan balances where terms were extended 90 days or more at or above contractual interest rates. (b) Loan restructurings whereby the original loan is restructured into two notes: an "A" note, which generally reflects the portion of the modified loan which is expected to be collected; and a "B" note, which is generally fully charged off. (c) Primarily loans secured by owner-occupied real estate. (d) 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 June 30, 2017 and 2016 of loans modified by principal deferral during the twelve-month periods ended June 30, 2017 and 2016 , and those principal deferrals which experienced a subsequent default during the three- and six-month periods ended June 30, 2017 and 2016 . 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. 2017 2016 (in millions) Balance at June 30 Subsequent Default in the Three Months Ended June 30 Subsequent Default in the Six Months Ended June 30 Balance at June 30 Subsequent Default in the Three Months Ended June 30 Subsequent Default in the Six Months Ended June 30 Principal deferrals: Business loans: Commercial $ 141 $ — $ — $ 233 $ 21 $ 21 Commercial mortgage: Commercial Real Estate business line (a) 1 — — 4 1 1 Other business lines (b) 7 — 7 — 6 Total commercial mortgage 8 — — 11 1 7 International — — — 1 — 1 Total business loans 149 — — 245 22 29 Retail loans: Consumer: Home equity 1 (c) — — 2 (c) — — Total principal deferrals $ 151 $ — $ — $ 247 $ 22 $ 29 (a) Primarily loans to real estate developers. (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.

Derivative And Credit-Related26

Derivative And Credit-Related Financial Instruments (Tables)	6 Months Ended
	Jun. 30, 2017
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 June 30, 2017 and December 31, 2016 . The table excludes commitments and warrants accounted for as derivatives. June 30, 2017 December 31, 2016 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 (b) $ 2,275 $ 10 $ — $ 2,275 $ 92 $ 4 Derivatives used as economic hedges Foreign exchange contracts: Spot, forwards and swaps 703 — 4 717 2 2 Total risk management purposes 2,978 10 4 2,992 94 6 Customer-initiated and other activities Interest rate contracts: Caps and floors written 627 — — 436 — 1 Caps and floors purchased 627 — — 436 1 — Swaps (b) 13,003 86 47 12,451 130 76 Total interest rate contracts 14,257 86 47 13,323 131 77 Energy contracts: Caps and floors written 297 — 19 419 1 31 Caps and floors purchased 297 19 — 419 31 1 Swaps 1,309 85 83 1,389 114 112 Total energy contracts 1,903 104 102 2,227 146 144 Foreign exchange contracts: Spot, forwards, options and swaps 1,583 36 30 1,509 36 27 Total customer-initiated and other activities 17,743 226 179 17,059 313 248 Total gross derivatives $ 20,721 236 183 $ 20,051 407 254 Amounts offset in the consolidated balance sheets: Netting adjustment - Offsetting derivative assets/liabilities (54 ) (54 ) (84 ) (84 ) Netting adjustment - Cash collateral received/posted (68 ) (4 ) (47 ) (45 ) Net derivatives included in the consolidated balance sheets (c) 114 125 276 125 Amounts not offset in the consolidated balance sheets: Marketable securities pledged under bilateral collateral agreements (10 ) (16 ) (19 ) (8 ) Net derivatives after deducting amounts not offset in the consolidated balance sheets $ 104 $ 109 $ 257 $ 117 (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) Due to clearinghouse rule changes, beginning January 1, 2017, variation margin payments are treated as settlements of derivative exposure rather than as collateral. As a result, these payments are now considered in determining the fair value of centrally cleared derivatives, resulting in centrally cleared derivatives having a fair value of approximately zero. (c) 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 $5 million at both June 30, 2017 and December 31, 2016 .
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 and the weighted average interest rates associated with amounts expected to be received or paid on interest rate swap agreements as of June 30, 2017 and December 31, 2016 . Weighted Average (dollar amounts in millions) Notional Amount Remaining Maturity (in years) Receive Rate Pay Rate (a) June 30, 2017 Swaps - fair value - receive fixed/pay floating rate Medium- and long-term debt designation $ 2,275 4.0 3.69 % 1.98 % December 31, 2016 Swaps - fair value - receive fixed/pay floating rate Medium- and long-term debt designation 2,275 4.5 3.69 1.80 (a) Variable rates paid on receive fixed swaps are based on six-month LIBOR rates in effect at June 30, 2017 and December 31, 2016 .
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 June 30, Six Months Ended June 30, (in millions) Location of Gain 2017 2016 2017 2016 Interest rate contracts Other noninterest income $ 7 $ 6 $ 13 $ 8 Energy contracts Other noninterest income 1 1 1 1 Foreign exchange contracts Foreign exchange income 11 9 22 19 Total $ 19 $ 16 $ 36 $ 28
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) June 30, 2017 December 31, 2016 Unused commitments to extend credit: Commercial and other $ 22,450 $ 24,333 Bankcard, revolving check credit and home equity loan commitments 2,849 2,658 Total unused commitments to extend credit $ 25,299 $ 26,991 Standby letters of credit $ 3,436 $ 3,623 Commercial letters of credit 40 46
Summary Of Criticized Letters Of Credit	The following table presents a summary of criticized standby and commercial letters of credit at June 30, 2017 and December 31, 2016 . 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) June 30, 2017 December 31, 2016 Total criticized standby and commercial letters of credit $ 103 $ 135 As a percentage of total outstanding standby and commercial letters of credit 3.0 % 3.7 %

Variable Interest Entities (V27

Variable Interest Entities (VIEs) (Tables)	6 Months Ended
	Jun. 30, 2017
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 June 30, Six Months Ended June 30, (in millions) 2017 2016 2017 2016 Other noninterest income: Amortization of other tax credit investments $ — $ — $ 1 $ — Provision for income taxes: Amortization of LIHTC investments 16 16 32 32 Low income housing tax credits (16 ) (15 ) (31 ) (31 ) Other tax benefits related to tax credit entities (6 ) (6 ) (12 ) (12 ) Total provision for income taxes $ (6 ) $ (5 ) $ (11 ) $ (11 )

Medium- And Long-Term Debt (Tab

Medium- And Long-Term Debt (Tables)	6 Months Ended
	Jun. 30, 2017
Debt Disclosure [Abstract]
Schedule Of Medium- And Long-Term Debt	Medium- and long-term debt is summarized as follows: (in millions) June 30, 2017 December 31, 2016 Parent company Subordinated notes: 3.80% subordinated notes due 2026 (a) $ 258 $ 256 Medium-term notes: 2.125% notes due 2019 (a) 349 348 Total parent company 607 604 Subsidiaries Subordinated notes: 5.20% subordinated notes due 2017 (a) 502 511 4.00% subordinated notes due 2025 (a) 351 347 7.875% subordinated notes due 2026 (a) 213 215 Total subordinated notes 1,066 1,073 Medium-term notes: 2.50% notes due 2020 (a) 670 667 Federal Home Loan Bank (FHLB) advances: Floating-rate based on FHLB auction rate due 2026 2,800 2,800 Other notes: 6.0% - 6.4% fixed-rate notes due 2018 to 2020 — 16 Total subsidiaries 4,536 4,556 Total medium- and long-term debt $ 5,143 $ 5,160 (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 Comprehensi29

Accumulated Other Comprehensive Loss (Tables)	6 Months Ended
	Jun. 30, 2017
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 six months ended June 30, 2017 and 2016 , including the amount of income tax expense (benefit) allocated to each component of other comprehensive income (loss). Six Months Ended June 30, (in millions) 2017 2016 Accumulated net unrealized (losses) gains on investment securities: Balance at beginning of period, net of tax $ (33 ) $ 9 Net unrealized holding gains arising during the period 21 191 Less: Provision for income taxes 8 70 Net unrealized holding gains arising during the period, net of tax 13 121 Less: Net losses realized as a yield adjustment in interest on investment securities (1 ) (2 ) Less: Benefit for income taxes — (1 ) Reclassification adjustment for net losses realized as a yield adjustment included in net income, net of tax (1 ) (1 ) Change in net unrealized gains on investment securities, net of tax 14 122 Balance at end of period, net of tax $ (19 ) $ 131 Accumulated defined benefit pension and other postretirement plans adjustment: Balance at beginning of period, net of tax $ (350 ) $ (438 ) Amortization of actuarial net loss 25 19 Amortization of prior service credit (13 ) — Amounts recognized in salaries and benefits expense 12 19 Less: Provision for income taxes 4 7 Change in defined benefit pension and other postretirement plans adjustment, net of tax 8 12 Balance at end of period, net of tax $ (342 ) $ (426 ) Total accumulated other comprehensive loss at end of period, net of tax $ (361 ) $ (295 )

Net Income Per Common Share (Ta

Net Income Per Common Share (Tables)	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Basic And Diluted Net Income Per Common Share	Basic and diluted net income per common share are presented in the following table. Three Months Ended June 30, Six Months Ended June 30, (in millions, except per share data) 2017 2016 2017 2016 Basic and diluted Net income $ 203 $ 104 $ 405 $ 164 Less: Income allocated to participating securities 1 1 3 2 Net income attributable to common shares $ 202 $ 103 $ 402 $ 162 Basic average common shares 175 173 175 173 Basic net income per common share $ 1.15 $ 0.60 $ 2.30 $ 0.94 Basic average common shares 175 173 175 173 Dilutive common stock equivalents: Net effect of the assumed exercise of stock options 3 2 3 2 Net effect of the assumed exercise of warrants 1 2 2 2 Diluted average common shares 179 177 180 177 Diluted net income per common share $ 1.13 $ 0.58 $ 2.24 $ 0.92
Schedule of Average Shares Excluded From Diluted Net Income Per Common Share Computation	The following average shares related to outstanding options to purchase shares of common stock were not included in the computation of diluted net income per common share because the options were anti-dilutive for the period. There were no anti-dilutive options for both the three- and six-month periods ended June 30, 2017 . (shares in millions) Three Months Ended June 30, 2016 Six Months Ended June 30, 2016 Average outstanding options 2.6 4.8 Range of exercise prices $46.68 - $59.86 $37.26 - $59.86

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	6 Months Ended
	Jun. 30, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]
Components of Net Periodic Benefit Cost	The components of net periodic benefit cost 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 June 30, Six Months Ended June 30, (in millions) 2017 2016 2017 2016 Service cost $ 7 $ 8 $ 14 $ 16 Interest cost 19 23 39 46 Expected return on plan assets (39 ) (40 ) (79 ) (81 ) Amortization of prior service (credit) cost (4 ) 1 (9 ) 2 Amortization of net loss 10 8 21 16 Net periodic defined benefit credit $ (7 ) $ — $ (14 ) $ (1 ) Non-Qualified Defined Benefit Pension Plan Three Months Ended June 30, Six Months Ended June 30, (in millions) 2017 2016 2017 2016 Service cost $ — $ 1 $ 1 $ 2 Interest cost 2 3 4 5 Amortization of prior service credit (2 ) (1 ) (4 ) (2 ) Amortization of net loss 2 1 4 3 Net periodic defined benefit cost $ 2 $ 4 $ 5 $ 8 Postretirement Benefit Plan Three Months Ended June 30, Six Months Ended June 30, (in millions) 2017 2016 2017 2016 Interest cost $ — $ 1 $ 1 $ 2 Expected return on plan assets — (1 ) (1 ) (2 ) Net periodic postretirement benefit cost $ — $ — $ — $ —

Restructuring Charges (Tables)

Restructuring Charges (Tables)	6 Months Ended
	Jun. 30, 2017
Restructuring and Related Activities [Abstract]
Restructuring and Related Costs	The following table presents changes in restructuring reserves, cumulative charges incurred to date and total expected restructuring charges: (in millions) Employee Costs Facilities Costs Technology Costs Other Costs Total Three Months Ended June 30, 2017 Balance at beginning of period $ 7 $ — $ 3 $ 3 $ 13 Restructuring charges 3 4 6 1 14 Payments (4 ) (4 ) (4 ) (2 ) (14 ) Adjustments for non-cash charges (a) — — (2 ) — (2 ) Balance at end of period $ 6 $ — $ 3 $ 2 $ 11 Three Months Ended June 30, 2016 Balance at beginning of period $ — $ — $ — $ — $ — Restructuring charges 46 — — 7 53 Payments — — — (3 ) (3 ) Balance at end of period $ 46 $ — $ — $ 4 $ 50 Six Months Ended June 30, 2017 Balance at beginning of period $ 10 $ 4 $ — $ 4 $ 18 Restructuring charges 4 5 12 4 25 Payments (8 ) (9 ) (4 ) (6 ) (27 ) Adjustments for non-cash charges (a) — — (5 ) — (5 ) Balance at end of period $ 6 $ — $ 3 $ 2 $ 11 Six Months Ended June 30, 2016 Balance at beginning of period $ — $ — $ — $ — $ — Restructuring charges 46 — — 7 53 Payments — — — (3 ) (3 ) Balance at end of period $ 46 $ — $ — $ 4 $ 50 Total restructuring charges incurred to date $ 56 $ 20 $ 12 $ 30 $ 118 Total expected restructuring charges (b) 56 30 - 35 20 - 35 34 140 - 160 (a) Adjustments for non-cash charges primarily include impairments of previously capitalized software costs. (b) Restructuring activities are expected to be substantially completed by 12/31/2018 .

Business Segment Information (T

Business Segment Information (Tables)	6 Months Ended
	Jun. 30, 2017
Segment Reporting [Abstract]
Business Segment Financial Results	Business segment financial results are as follows: (dollar amounts in millions) Business Retail Wealth Management Finance Other Total Three Months Ended June 30, 2017 Earnings summary: Net interest income (expense) $ 336 $ 162 $ 42 $ (49 ) $ 9 $ 500 Provision for credit losses 12 5 (2 ) — 2 17 Noninterest income 152 48 64 10 2 276 Noninterest expenses 196 180 71 (1 ) 11 457 Provision (benefit) for income taxes 100 9 14 (17 ) (7 ) (a) 99 Net income (loss) $ 180 $ 16 $ 23 $ (21 ) $ 5 $ 203 Net credit-related charge-offs (recoveries) $ 10 $ 9 $ (1 ) $ — $ — $ 18 Selected average balances: Assets $ 38,853 $ 6,487 $ 5,432 $ 13,936 $ 6,610 $ 71,318 Loans 37,580 5,865 5,278 — — 48,723 Deposits 28,748 23,935 4,106 156 183 57,128 Statistical data: Return on average assets (b) 1.85 % 0.27 % 1.76 % N/M N/M 1.14 % Efficiency ratio (c) 40.19 84.79 66.44 N/M N/M 58.63 (dollar amounts in millions) Business Retail Wealth Management Finance Other Total Three Months Ended June 30, 2016 Earnings summary: Net interest income (expense) $ 349 $ 154 $ 42 $ (105 ) $ 5 $ 445 Provision for credit losses 46 1 3 — (1 ) 49 Noninterest income 143 48 62 10 5 268 Noninterest expenses 221 205 81 — 11 518 Provision (benefit) for income taxes 74 (2 ) 7 (36 ) (1 ) 42 Net income (loss) $ 151 $ (2 ) $ 13 $ (59 ) $ 1 $ 104 Net credit-related charge-offs $ 42 $ 1 $ 4 $ — $ — $ 47 Selected average balances: Assets $ 39,983 $ 6,558 $ 5,215 $ 13,927 $ 4,985 $ 70,668 Loans 38,574 5,879 5,016 — — 49,469 Deposits 28,441 23,546 4,213 50 271 56,521 Statistical data: Return on average assets (b) 1.52 % (0.04 )% 0.99 % N/M N/M 0.59 % Efficiency ratio (c) 44.75 101.58 78.22 N/M N/M 72.43 (a) Includes tax benefit of $5 million from employee stock transactions. (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 (fully taxable equivalent basis) and noninterest income excluding net securities gains (losses). N/M – not meaningful (dollar amounts in millions) Business Retail Wealth Management Finance Other Total Six Months Ended June 30, 2017 Earnings summary: Net interest income (expense) $ 668 $ 322 $ 83 $ (120 ) $ 17 $ 970 Provision for credit losses 22 17 (3 ) — (3 ) 33 Noninterest income 296 96 128 21 6 547 Noninterest expenses 393 359 141 (2 ) 23 914 Provision (benefit) for income taxes 192 15 27 (41 ) (28 ) (a) 165 Net income (loss) $ 357 $ 27 $ 46 $ (56 ) $ 31 $ 405 Net credit-related charge-offs (recoveries) $ 40 $ 14 $ (3 ) $ — $ — $ 51 Selected average balances: Assets $ 38,474 $ 6,506 $ 5,419 $ 13,940 $ 7,228 $ 71,567 Loans 37,169 5,880 5,264 — — 48,313 Deposits 29,196 23,866 4,042 149 199 57,452 Statistical data: Return on average assets (b) 1.87 % 0.22 % 1.73 % N/M N/M 1.14 % Efficiency ratio (c) 40.75 85.39 66.81 N/M N/M 60.10 (dollar amounts in millions) Business Retail Wealth Management Finance Other Total Six Months Ended June 30, 2016 Earnings summary: Net interest income (expense) $ 706 $ 309 $ 85 $ (218 ) $ 10 $ 892 Provision for credit losses 197 4 (2 ) — (2 ) 197 Noninterest income 279 92 120 21 — 512 Noninterest expenses 427 385 154 (1 ) 11 976 Provision (benefit) for income taxes 118 3 19 (74 ) 1 67 Net income (loss) $ 243 $ 9 $ 34 $ (122 ) $ — $ 164 Net credit-related charge-offs $ 99 $ 3 $ 3 $ — $ — $ 105 Selected average balances: Assets $ 39,574 $ 6,551 $ 5,189 $ 13,858 $ 4,776 $ 69,948 Loans 38,068 5,873 4,990 — — 48,931 Deposits 28,778 23,328 4,192 73 244 56,615 Statistical data: Return on average assets (b) 1.24 % 0.07 % 1.32 % N/M N/M 0.47 % Efficiency ratio (c) 43.28 95.42 75.15 N/M N/M 69.25 (a) Includes tax benefit of $29 million from employee stock transactions. (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 (fully taxable equivalent basis) and noninterest income excluding net securities gains. N/M – not meaningful
Market Segment Financial Results	Market segment financial results are as follows: (dollar amounts in millions) Michigan California Texas Other Finance Total Three Months Ended June 30, 2017 Earnings summary: Net interest income (expense) $ 167 $ 178 $ 113 $ 82 $ (40 ) $ 500 Provision for credit losses (2 ) 24 (15 ) 8 2 17 Noninterest income 81 45 33 105 12 276 Noninterest expenses 145 98 94 110 10 457 Provision (benefit) for income taxes 38 40 25 20 (24 ) (a) 99 Net income (loss) $ 67 $ 61 $ 42 $ 49 $ (16 ) $ 203 Net credit-related charge-offs (recoveries) $ (1 ) $ 8 $ 5 $ 6 $ — $ 18 Selected average balances: Assets $ 13,371 $ 18,446 $ 10,481 $ 8,474 $ 20,546 $ 71,318 Loans 12,712 18,194 10,015 7,802 — 48,723 Deposits 21,698 17,344 9,632 8,115 339 57,128 Statistical data: Return on average assets (b) 1.20 % 1.33 % 1.52 % 2.24 % N/M 1.14 % Efficiency ratio (c) 58.14 43.82 64.37 58.45 N/M 58.63 (dollar amounts in millions) Michigan California Texas Other Finance Total Three Months Ended June 30, 2016 Earnings summary: Net interest income (expense) $ 164 $ 176 $ 117 $ 88 $ (100 ) $ 445 Provision for credit losses 3 18 32 (3 ) (1 ) 49 Noninterest income 81 38 32 102 15 268 Noninterest expenses 159 120 113 115 11 518 Provision (benefit) for income taxes 28 27 2 22 (37 ) 42 Net income (loss) $ 55 $ 49 $ 2 $ 56 $ (58 ) $ 104 Net credit-related charge-offs (recoveries) $ — $ 17 $ 31 $ (1 ) $ — $ 47 Selected average balances: Assets $ 13,142 $ 18,155 $ 11,287 $ 9,172 $ 18,912 $ 70,668 Loans 12,502 17,865 10,841 8,261 — 49,469 Deposits 21,519 16,967 10,052 7,662 321 56,521 Statistical data: Return on average assets (b) 1.00 % 1.08 % 0.07 % 2.45 % N/M 0.59 % Efficiency ratio (c) 64.65 55.73 75.89 60.77 N/M 72.43 (a) Includes tax benefit of $5 million from employee stock transactions. (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 (fully taxable equivalent basis) and noninterest income excluding net securities gains. N/M – not meaningful (dollar amounts in millions) Michigan California Texas Other Finance Total Six Months Ended June 30, 2017 Earnings summary: Net interest income (expense) $ 337 $ 349 $ 226 $ 161 $ (103 ) $ 970 Provision for credit losses (4 ) 45 (24 ) 19 (3 ) 33 Noninterest income 164 86 65 205 27 547 Noninterest expenses 295 194 188 216 21 914 Provision (benefit) for income taxes 75 76 47 36 (69 ) (a) 165 Net income (loss) $ 135 $ 120 $ 80 $ 95 $ (25 ) $ 405 Net credit-related charge-offs (recoveries) $ (4 ) $ 18 $ 27 $ 10 $ — $ 51 Selected average balances: Assets $ 13,313 $ 18,203 $ 10,518 $ 8,365 $ 21,168 $ 71,567 Loans 12,650 17,938 10,062 7,663 — 48,313 Deposits 21,923 17,294 9,871 8,016 348 57,452 Statistical data: Return on average assets (b) 1.20 % 1.33 % 1.44 % 2.19 % N/M 1.14 % Efficiency ratio (c) 58.75 44.50 64.58 58.87 N/M 60.10 (dollar amounts in millions) Michigan California Texas Other Finance Total Six Months Ended June 30, 2016 Earnings summary: Net interest income (expense) $ 338 $ 351 $ 238 $ 173 $ (208 ) $ 892 Provision for credit losses (3 ) 12 201 (11 ) (2 ) 197 Noninterest income 157 76 62 196 21 512 Noninterest expenses 310 224 213 219 10 976 Provision (benefit) for income taxes 63 70 (39 ) 46 (73 ) 67 Net income (loss) $ 125 $ 121 $ (75 ) $ 115 $ (122 ) $ 164 Net credit-related charge-offs (recoveries) $ 5 $ 25 $ 78 $ (3 ) $ — $ 105 Selected average balances: Assets $ 13,194 $ 17,926 $ 11,291 $ 8,903 $ 18,634 $ 69,948 Loans 12,560 17,653 10,802 7,916 — 48,931 Deposits 21,594 16,823 10,214 7,667 317 56,615 Statistical data: Return on average assets (b) 1.12 % 1.36 % (1.28 )% 2.60 % N/M 0.47 % Efficiency ratio (c) 62.31 52.11 70.95 59.45 N/M 69.25 (a) Includes tax benefit of $29 million from employee stock transactions. (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 (fully taxable equivalent basis) and noninterest income excluding net securities gains. N/M – not meaningful

Basis of Presentation and Acc34

Basis of Presentation and Accounting Policies Basis of Presentation and Accounting Policies (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Amount reclassified from operating activities for payments made to tax authorities when directly withholding shares for employee tax withholding purposes			$ 257	$ 118
Net excess tax benefits for awards that vested, were exercised or expired included in the provision for income taxes	$ 99	$ 42	165	67
Net excess tax benefits for awards that vested, were exercised or expired included in equity			82	0
Accounting Standards Update 2016-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Amount reclassified to operating activities for excess tax benefits from share-based compensation				0
Amount reclassified from operating activities for payments made to tax authorities when directly withholding shares for employee tax withholding purposes				4
Net excess tax benefits for awards that vested, were exercised or expired included in the provision for income taxes	$ 5		$ 29
Net excess tax benefits for awards that vested, were exercised or expired included in equity		$ 0		$ 0

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Recurring
Transfers into or out of Level 1 or Level 2 or Level 3	$ 0	$ 0	$ 0	$ 0
Total liabilities at fair value	271		271		$ 341
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		Jun. 30, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	[1]	$ 10,944	$ 10,787
Derivative assets		236	407
Derivative liabilities	[2]	125	125
Equity and other non-debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale		109	129
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		2,773	2,779
Residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale	[3]	8,057	7,872
State and municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale		5	7
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities			88
Investment securities available-for-sale		10,944	10,787
Derivative assets		238	410
Total assets at fair value		11,270	11,285
Derivative liabilities		183	254
Deferred compensation plan liabilities		88	87
Total liabilities at fair value		271	341
Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities			88
Investment securities available-for-sale		2,836	2,861
Derivative assets		0	0
Total assets at fair value		2,924	2,949
Derivative liabilities		0	0
Deferred compensation plan liabilities		88	87
Total liabilities at fair value		88	87
Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities			0
Investment securities available-for-sale		8,057	7,872
Derivative assets		223	396
Total assets at fair value		8,280	8,268
Derivative liabilities		183	254
Deferred compensation plan liabilities		0	0
Total liabilities at fair value		183	254
Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities			0
Investment securities available-for-sale		51	54
Derivative assets		15	14
Total assets at fair value		66	68
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		96	223
Derivative liabilities		47	81
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		83	212
Derivative liabilities		47	81
Recurring | Interest rate contracts | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		13	11
Derivative liabilities		0	0
Recurring | Energy derivative contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		104	146
Derivative liabilities		102	144
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		104	146
Derivative liabilities		102	144
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		36	38
Derivative liabilities		34	29
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		36	38
Derivative liabilities		34	29
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 | Warrants
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		2	3
Recurring | Warrants | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		0	0
Recurring | Warrants | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		0	0
Recurring | Warrants | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		2	3
Recurring | Deferred compensation plan assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities		88	87
Recurring | Deferred compensation plan assets | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities		88	87
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]
Trading securities			1
Investment securities available-for-sale		109	129
Recurring | Equity and other non-debt securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities			1
Investment securities available-for-sale		63	82
Recurring | Equity and other non-debt securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities			0
Investment securities available-for-sale		0	0
Recurring | Equity and other non-debt securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities			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		2,773	2,779
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		2,773	2,779
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	[4]	8,057	7,872
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	[4]	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	[4]	8,057	7,872
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	[4]	0	0
Recurring | State and municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale		5	7
Recurring | State and municipal securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale		0	0
Recurring | State and municipal securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities available-for-sale		$ 0	$ 0
[1]	Included auction-rate securities at amortized cost and fair value of $52 million and $51 million, respectively as of June 30, 2017 and $55 million and $54 million, respectively, as of December 31, 2016.
[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 $5 million at both June 30, 2017 and December 31, 2016.
[3]	Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises.
[4]	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				6 Months Ended
		Jun. 30, 2017		Jun. 30, 2016		Jun. 30, 2017		Jun. 30, 2016
Interest rate contracts
Balance at beginning of period		$ 11		$ 20		$ 11		$ 9
Realized gains (losses) recorded in earnings		0		0		0		0
Unrealized gains (losses) recorded in earnings	[1]	2		7		2		18
Gains (losses) recorded in other comprehensive income		0		0		0		0
Redemptions		0		0		0		0
Sales		0		0		0		0
Balance at end of period		13		27		13		27
Warrants
Balance at beginning of period		2		2		3		2
Realized gains (losses) recorded in earnings		4	[1]	0		5	[1]	0
Unrealized gains (losses) recorded in earnings		0		1	[1]	(1)	[1]	1	[1]
Gains (losses) recorded in other comprehensive income		0		0		0		0
Redemptions		0		0		0		0
Sales		(4)		(1)		(5)		(1)
Balance at end of period		2		2		2		2
Investment Securities Available-For-Sale
Balance at beginning of period		51		61		54		77
Realized gains (losses) recorded in earnings		0		0		0		0
Unrealized gains (losses) recorded in earnings		0		0		0		0
Gains (losses) recorded in other comprehensive income		0		(3)		0		(4)
Redemptions		0		(1)		(3)		(16)
Sales		0		0		0		0
Balance at end of period		51		57		51		57
State and municipal securities | Investment Securities Available-For-Sale
Balance at beginning of period	[2]	5		9		7		9
Realized gains (losses) recorded in earnings	[2]	0		0		0		0
Unrealized gains (losses) recorded in earnings	[2]	0		0		0		0
Gains (losses) recorded in other comprehensive income	[2]	0		0		0		0
Redemptions	[2]	0		(1)		(2)		(1)
Sales	[2]	0		0		0		0
Balance at end of period	[2]	5		8		5		8
Equity and other non-debt securities | Investment Securities Available-For-Sale
Balance at beginning of period	[2]	46		51		47		67
Realized gains (losses) recorded in earnings	[2]	0		0		0		0
Unrealized gains (losses) recorded in earnings	[2]	0		0		0		0
Gains (losses) recorded in other comprehensive income	[2]	0		(3)		0		(4)
Redemptions	[2]	0		0		(1)		(15)
Sales	[2]	0		0		0		0
Balance at end of period	[2]	$ 46		48		$ 46		48
Corporate debt securities | Investment Securities Available-For-Sale
Balance at beginning of period	[2]			1				1
Realized gains (losses) recorded in earnings	[2]			0				0
Unrealized gains (losses) recorded in earnings	[2]			0				0
Gains (losses) recorded in other comprehensive income	[2]			0				0
Redemptions	[2]			0				0
Sales	[2]			0				0
Balance at end of period	[2]			$ 1				$ 1
[1]	Realized and unrealized gains and losses due to changes in fair value recorded in "other noninterest income" on the consolidated statements of comprehensive income.
[2]	Auction-rate securities.

Fair Value Measurements (Asse38

Fair Value Measurements (Assets And Liabilities Recorded At Fair Value On A Nonrecurring Basis) (Details) - Nonrecurring - Level 3 - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans	$ 271	$ 282
Other real estate	13	1
Total assets at fair value	284	283
Commercial borrower | Domestic loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans	248	256
Commercial borrower | International loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans	5	11
Commercial borrower | Commercial Mortgage Loans | Domestic loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans	$ 18	$ 15

Fair Value Measurements (Quanti

Fair Value Measurements (Quantitative Information About Level 3 Measurements) (Details) - USD ($) $ in Millions		6 Months Ended	12 Months Ended
		Jun. 30, 2017	Dec. 31, 2016
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Investment securities available-for-sale	[1]	$ 10,944	$ 10,787
Recurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Investment securities available-for-sale		10,944	10,787
Recurring | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Investment securities available-for-sale		51	54
Recurring | State and municipal securities | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Investment securities available-for-sale	[2]	$ 5	$ 7
Recurring | State and municipal securities | Minimum | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Unobservable input, discount rate	[2]	5.00%	4.00%
Unobservable input, workout period	[2]	1 year	1 year
Recurring | State and municipal securities | Maximum | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Unobservable input, discount rate	[2]	7.00%	6.00%
Unobservable input, workout period	[2]	2 years	2 years
Recurring | Equity and other non-debt securities | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Investment securities available-for-sale	[2]	$ 46	$ 47
Recurring | Equity and other non-debt securities | Minimum | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Unobservable input, discount rate	[2]	7.00%	7.00%
Unobservable input, workout period	[2]	1 year	1 year
Recurring | Equity and other non-debt securities | Maximum | Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Unobservable input, discount rate	[2]	9.00%	9.00%
Unobservable input, workout period	[2]	2 years	2 years
[1]	Included auction-rate securities at amortized cost and fair value of $52 million and $51 million, respectively as of June 30, 2017 and $55 million and $54 million, respectively, as of December 31, 2016.
[2]	Auction-rate securities.

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		Jun. 30, 2017	Dec. 31, 2016
Cash and due from banks		$ 1,372	$ 1,249
Interest-bearing deposits with banks		4,259	5,969
Investment securities held-to-maturity		1,430	1,582
Total loans, net of allowance for loan losses		48,703	48,358
Demand deposits (noninterest-bearing)		31,210	31,540
Customer certificates of deposit		2,438	2,806
Total deposits		56,781	58,985
Short-term borrowings		541	25
Medium- and long-term debt		5,143	5,160
Carrying Amount
Cash and due from banks		1,372	1,249
Interest-bearing deposits with banks		4,259	5,969
Investment securities held-to-maturity		1,430	1,582
Loans held-for-sale		1	4
Total loans, net of allowance for loan losses	[1]	48,703	48,358
Customers' liability on acceptances outstanding		3	5
Restricted equity investments		228	207
Nonmarketable equity securities	[2]	6	11
Demand deposits (noninterest-bearing)		31,210	31,540
Interest-bearing deposits		23,133	24,639
Customer certificates of deposit		2,438	2,806
Total deposits		56,781	58,985
Short-term borrowings		541	25
Acceptances outstanding		3	5
Medium- and long-term debt		5,143	5,160
Credit-related financial instruments		(76)	(73)
Estimated Fair Value
Cash and due from banks		1,372	1,249
Interest-bearing deposits with banks		4,259	5,969
Investment securities held-to-maturity		1,424	1,576
Loans held-for-sale		1	4
Total loans, net of allowance for loan losses	[1]	48,468	48,250
Customers' liability on acceptances outstanding		3	5
Restricted equity investments		228	207
Nonmarketable equity securities	[2]	10	16
Demand deposits (noninterest-bearing)		31,210	31,540
Interest-bearing deposits		23,133	24,639
Customer certificates of deposit		2,418	2,731
Total deposits		56,761	58,910
Short-term borrowings		541	25
Acceptances outstanding		3	5
Medium- and long-term debt		5,138	5,132
Credit-related financial instruments		(76)	(73)
Level 1 | Estimated Fair Value
Cash and due from banks		1,372	1,249
Interest-bearing deposits with banks		4,259	5,969
Investment securities held-to-maturity		0	0
Loans held-for-sale		0	0
Total loans, net of allowance for loan losses	[1]	0	0
Customers' liability on acceptances outstanding		3	5
Restricted equity investments		228	207
Demand deposits (noninterest-bearing)		0	0
Interest-bearing deposits		0	0
Customer certificates of deposit		0	0
Total deposits		0	0
Short-term borrowings		541	25
Acceptances outstanding		3	5
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
Investment securities held-to-maturity		1,424	1,576
Loans held-for-sale		1	4
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)		31,210	31,540
Interest-bearing deposits		23,133	24,639
Customer certificates of deposit		2,418	2,731
Total deposits		56,761	58,910
Short-term borrowings		0	0
Acceptances outstanding		0	0
Medium- and long-term debt		5,138	5,132
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
Investment securities held-to-maturity		0	0
Loans held-for-sale		0	0
Total loans, net of allowance for loan losses	[1]	48,468	48,250
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
Total deposits		0	0
Short-term borrowings		0	0
Acceptances outstanding		0	0
Medium- and long-term debt		0	0
Credit-related financial instruments		(76)	(73)
Nonrecurring
Total loans, net of allowance for loan losses		$ 271	$ 282
[1]	Included $271 million and $282 million of impaired loans recorded at fair value on a nonrecurring basis at June 30, 2017 and December 31, 2016, 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		6 Months Ended
		Jun. 30, 2017USD ($)Security	Dec. 31, 2016USD ($)
Securities with no credit impairment in unrealized loss position | Security		233
Investment securities available-for-sale, Amortized Cost	[1]	$ 10,965	$ 10,829
Investment securities available-for-sale, Fair Value	[1]	10,944	10,787
Investment securities held-to-maturity, Amortized Cost		1,430	1,582
Investment securities held-to-maturity, Fair Value		1,424
Carrying value of securities pledged		1,100
Liabilities secured by pledged collateral		$ 600
U.S. Treasury and other U.S. government agency securities
Securities with no credit impairment in unrealized loss position		4
Investment securities available-for-sale, Amortized Cost		$ 2,762	2,772
Investment securities available-for-sale, Fair Value		$ 2,773	2,779
Residential mortgage-backed securities
Securities with no credit impairment in unrealized loss position | Security		188
Investment securities available-for-sale, Amortized Cost	[2]	$ 8,089	7,921
Investment securities available-for-sale, Fair Value	[2]	8,057	7,872
Investment securities held-to-maturity, Amortized Cost	[2],[3]	1,430	1,582
Investment securities held-to-maturity, Fair Value	[2],[3]	$ 1,424	1,576
Auction Rate Preferred Securities
Securities with no credit impairment in unrealized loss position		28
Auction-Rate State And Municipal Securities
Securities with no credit impairment in unrealized loss position		13
Auction-rate securities
ARS portfolio redeemed or sold since acquisition		96.00%
ARS portfolio redeemed or sold since acquisition at or above cost		90.00%
Investment securities available-for-sale, Amortized Cost		$ 52	55
Investment securities available-for-sale, Fair Value		51	$ 54
Prepayment options | Residential mortgage-backed securities
Investment securities available-for-sale, Amortized Cost		8,100
Investment securities available-for-sale, Fair Value		8,100
Investment securities held-to-maturity, Amortized Cost		1,400
Investment securities held-to-maturity, Fair Value		$ 1,400
[1]	Included auction-rate securities at amortized cost and fair value of $52 million and $51 million, respectively as of June 30, 2017 and $55 million and $54 million, respectively, as of December 31, 2016.
[2]	Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises.
[3]	The amortized cost of investment securities held-to-maturity included net unrealized losses of $11 million at June 30, 2017 and $12 million at December 31, 2016 related to securities transferred from available-for-sale, which are included in accumulated other comprehensive loss.

Investment Securities (Summary

Investment Securities (Summary Of Investment Securities Available-For-Sale) (Details) - USD ($) $ in Millions		Jun. 30, 2017	Dec. 31, 2016
Investment securities available-for-sale, Amortized Cost	[1]	$ 10,965	$ 10,829
Investment securities available-for-sale securities, Gross Unrealized Gains	[1]	57	57
Investment securities available-for-sale securities, Gross Unrealized Losses	[1]	78	99
Investment securities available-for-sale, Fair Value	[1]	10,944	10,787
Investment securities held-to-maturity, Amortized Cost		1,430	1,582
Investment securities held-to-maturity, Fair Value		1,424
Net unrealized losses on available-for-sale securities transferred to held-to-maturity		11	12
U.S. Treasury and other U.S. government agency securities
Investment securities available-for-sale, Amortized Cost		2,762	2,772
Investment securities available-for-sale securities, Gross Unrealized Gains		11	8
Investment securities available-for-sale securities, Gross Unrealized Losses		0	1
Investment securities available-for-sale, Fair Value		2,773	2,779
Residential mortgage-backed securities
Investment securities available-for-sale, Amortized Cost	[2]	8,089	7,921
Investment securities available-for-sale securities, Gross Unrealized Gains	[2]	45	48
Investment securities available-for-sale securities, Gross Unrealized Losses	[2]	77	97
Investment securities available-for-sale, Fair Value	[2]	8,057	7,872
Investment securities held-to-maturity, Amortized Cost	[2],[3]	1,430	1,582
Investment securities held-to-maturity, Gross Unrealized Gains	[2],[3]	1	1
Investment securities held-to-maturity, Gross Unrealized Losses	[2],[3]	7	7
Investment securities held-to-maturity, Fair Value	[2],[3]	1,424	1,576
State and municipal securities
Investment securities available-for-sale, Amortized Cost		5	7
Investment securities available-for-sale securities, Gross Unrealized Gains		0	0
Investment securities available-for-sale securities, Gross Unrealized Losses		0	0
Investment securities available-for-sale, Fair Value		5	7
Equity and other non-debt securities
Investment securities available-for-sale, Amortized Cost		109	129
Investment securities available-for-sale securities, Gross Unrealized Gains		1	1
Investment securities available-for-sale securities, Gross Unrealized Losses		1	1
Investment securities available-for-sale, Fair Value		109	129
Auction-rate securities
Investment securities available-for-sale, Amortized Cost		52	55
Investment securities available-for-sale, Fair Value		$ 51	$ 54
[1]	Included auction-rate securities at amortized cost and fair value of $52 million and $51 million, respectively as of June 30, 2017 and $55 million and $54 million, respectively, as of December 31, 2016.
[2]	Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises.
[3]	The amortized cost of investment securities held-to-maturity included net unrealized losses of $11 million at June 30, 2017 and $12 million at December 31, 2016 related to securities transferred from available-for-sale, which are included in accumulated other comprehensive loss.

Investment Securities (Summar43

Investment Securities (Summary Of Investment Securities Available-For-Sale In Unrealized Loss Positions) (Details) - USD ($) $ in Millions		Jun. 30, 2017		Dec. 31, 2016
Temporarily Impaired Less than 12 months, Fair Value		$ 4,968		$ 5,555
Temporarily Impaired Less than 12 Months, Unrealized Losses		69		88
Temporarily Impaired 12 months or more, Fair Value		1,124		1,195
Temporarily Impaired 12 Months or more, Unrealized Losses		28		32
Temporarily Impaired Total, Fair Value		6,092		6,750
Temporarily Impaired Total, Unrealized Losses		97		120
U.S. Treasury and other U.S. government agency securities
Temporarily Impaired Less than 12 months, Fair Value		301		527
Temporarily Impaired Less than 12 Months, Unrealized Losses		0	[1]	1
Temporarily Impaired 12 months or more, Fair Value		0		0
Temporarily Impaired 12 Months or more, Unrealized Losses		0		0
Temporarily Impaired Total, Fair Value		301		527
Temporarily Impaired Total, Unrealized Losses		0	[1]	1
Residential mortgage-backed securities
Temporarily Impaired Less than 12 months, Fair Value	[2]	4,667		4,992
Temporarily Impaired Less than 12 Months, Unrealized Losses	[2]	69		87
Temporarily Impaired 12 months or more, Fair Value	[2]	1,073		1,177
Temporarily Impaired 12 Months or more, Unrealized Losses	[2]	27		32
Temporarily Impaired Total, Fair Value	[2]	5,740		6,169
Temporarily Impaired Total, Unrealized Losses	[2]	96		119
State and municipal securities
Temporarily Impaired Less than 12 months, Fair Value	[3]	0		0
Temporarily Impaired Less than 12 Months, Unrealized Losses	[3]	0		0
Temporarily Impaired 12 months or more, Fair Value	[3]	5		7
Temporarily Impaired 12 Months or more, Unrealized Losses	[1],[3]	0		0
Temporarily Impaired Total, Fair Value	[3]	5		7
Temporarily Impaired Total, Unrealized Losses	[1],[3]	0		0
Equity and other non-debt securities
Temporarily Impaired Less than 12 months, Fair Value	[3]	0		36
Temporarily Impaired Less than 12 Months, Unrealized Losses	[3]	0		0	[1]
Temporarily Impaired 12 months or more, Fair Value	[3]	46		11
Temporarily Impaired 12 Months or more, Unrealized Losses	[3]	1		0	[1]
Temporarily Impaired Total, Fair Value	[3]	46		47
Temporarily Impaired Total, Unrealized Losses	[3]	$ 1		$ 0	[1]
[1]	Unrealized losses less than $0.5 million.
[2]	Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises
[3]	Primarily auction-rate securities.

Investment Securities Investmen

Investment Securities Investment Securities (Gains and Losses on Available-For-Sale Securities) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Investments, Debt and Equity Securities [Abstract]
Securities gains		$ 0	$ 0	$ 1	$ 0
Securities losses	[1]	(2)	(1)	(3)	(3)
Net securities losses		$ (2)	$ (1)	$ (2)	$ (3)
[1]	Primarily charges related to a derivative contract tied to the conversion rate of Visa Class B shares.

Investment Securities (Contract

Investment Securities (Contractual Maturity Distribution Of Debt Securities) (Details) - USD ($) $ in Millions		Jun. 30, 2017	Dec. 31, 2016
Available-for-sale, Within one year, Amortized Cost		$ 20
Available-for-sale, After one year through five years, Amortized Cost		2,991
Available-for-sale, After five years through ten years, Amortized Cost		1,833
Available-for-sale, After ten years, Amortized Cost		6,012
Available-for-sale, Subtotal, Amortized Cost		10,856
Available-for-sale, Within one year, Fair Value		20
Available-for-sale, After one year through five years, Fair Value		3,002
Available-for-sale, After five years through ten years, Fair Value		1,861
Available-for-sale, After ten years, Fair Value		5,952
Available-for-sale, Subtotal, Fair Value		10,835
Investment securities available-for-sale, Amortized Cost	[1]	10,965	$ 10,829
Investment securities available-for-sale, Fair Value	[1]	10,944	10,787
Held-to-maturity, Within one year, Amortized Cost		0
Held-to-maturity, After one year through five years, Amortized Cost		0
Held-to-maturity, After five years through ten years, Amortized Cost		21
Held-to-maturities, After ten years, Amortized Cost		1,409
Held-to-maturity Securities		1,430	1,582
Held-to-maturity, Within one year, Fair Value		0
Held-to-maturity Securities, After one year through five years, Fair Value		0
Held-to-maturity Securities, After five years through ten years, Fair Value		20
Held-to-maturity Securities, After ten years, Fair Value		1,404
Held-to-maturity Securities, Fair Value		1,424
Equity and other non-debt securities
Investment securities available-for-sale, Amortized Cost		109	129
Investment securities available-for-sale, Fair Value		$ 109	$ 129
[1]	Included auction-rate securities at amortized cost and fair value of $52 million and $51 million, respectively as of June 30, 2017 and $55 million and $54 million, respectively, as of December 31, 2016.

Credit Quality And Allowance 46

Credit Quality And Allowance For Credit Losses (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Retail loans secured by residential real estate in process of foreclosure	$ 0		$ 0		$ 0
Commitments to lend additional funds to TDR borrowers	47		$ 47		$ 24
Interest Rate Reductions
Days past due defined as subsequent default			90 days	90 days
Balance	3	$ 4	$ 3	$ 4
Subsequent default during period	0	0	$ 0	$ 0
AB Note Restructures
Days past due defined as subsequent default			90 days	90 days
Balance	68	36	$ 68	$ 36
Subsequent default during period	$ 0	$ 1	$ 0	$ 1

Credit Quality And Allowance 47

Credit Quality And Allowance For Credit Losses (Aging Analysis Of Loans) (Details) - USD ($) $ in Millions		Jun. 30, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		$ 136	$ 148
Nonaccrual loans		493	582
Current loans		48,779	48,358
Total loans		49,408	49,088
30 to 59 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		79	106
60 to 89 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		27	23
90 days or more past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		30	19
Business loans | Commercial borrower
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		109	130
Nonaccrual loans		434	511
Current loans		44,354	43,983
Total loans		44,897	44,624
Business loans | Commercial borrower | 30 to 59 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		64	94
Business loans | Commercial borrower | 60 to 89 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		15	17
Business loans | Commercial borrower | 90 days or more past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		30	19
Business loans | Commercial borrower | Domestic loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		72	56
Nonaccrual loans		379	445
Current loans		30,998	30,493
Total loans		31,449	30,994
Business loans | Commercial borrower | Domestic loans | 30 to 59 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		38	30
Business loans | Commercial borrower | Domestic loans | 60 to 89 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		11	12
Business loans | Commercial borrower | Domestic loans | 90 days or more past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		23	14
Business loans | Commercial borrower | International loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		8	1
Nonaccrual loans		6	14
Current loans		1,131	1,243
Total loans		1,145	1,258
Business loans | Commercial borrower | International loans | 30 to 59 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		8	1
Business loans | Commercial borrower | International loans | 60 to 89 days past due and still accruing
Financing Receivable, Recorded Investment, 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, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		1	0
Nonaccrual loans		0	0
Current loans		2,856	2,869
Total loans		2,857	2,869
Business loans | Real estate construction | Commercial borrower | Domestic loans | 30 to 59 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | 60 to 89 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		1	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | 90 days or more past due and still accruing
Financing Receivable, Recorded Investment, 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, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing	[1]	0	0
Nonaccrual loans	[1]	0	0
Current loans	[1]	2,560	2,485
Total loans	[1],[2]	2,560	2,485
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, Recorded Investment, 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 | 60 to 89 days past due and still accruing
Financing Receivable, Recorded Investment, 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, Recorded Investment, 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, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing	[3]	1	0
Nonaccrual loans	[3]	0	0
Current loans	[3]	296	384
Total loans	[3],[4]	297	384
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines | 30 to 59 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing	[3]	0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines | 60 to 89 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing	[3]	1	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines | 90 days or more past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing	[3]	0	0
Business loans | Real estate mortgage | Commercial borrower | Domestic loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		28	73
Nonaccrual loans		41	46
Current loans		8,905	8,812
Total loans		8,974	8,931
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | 30 to 59 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		18	63
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | 60 to 89 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		3	5
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | 90 days or more past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		7	5
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing	[1]	16	5
Nonaccrual loans	[1]	9	9
Current loans	[1]	1,801	2,004
Total loans	[1],[2]	1,826	2,018
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line | 30 to 59 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing	[1]	16	5
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line | 60 to 89 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing	[1]	0	0
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line | 90 days or more past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing	[1]	0	0
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing	[3]	12	68
Nonaccrual loans	[3]	32	37
Current loans	[3]	7,104	6,808
Total loans	[3],[4]	7,148	6,913
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Other business lines | 30 to 59 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing	[3]	2	58
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Other business lines | 60 to 89 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing	[3]	3	5
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Other business lines | 90 days or more past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing	[3]	7	5
Business loans | Lease financing | Commercial borrower | Domestic loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		0	0
Nonaccrual loans		8	6
Current loans		464	566
Total loans		472	572
Business loans | Lease financing | Commercial borrower | Domestic loans | 30 to 59 days past due and still accruing
Financing Receivable, Recorded Investment, 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, Recorded Investment, 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, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		0	0
Retail loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		27	18
Nonaccrual loans		59	71
Current loans		4,425	4,375
Total loans		4,511	4,464
Retail loans | 30 to 59 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		15	12
Retail loans | 60 to 89 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		12	6
Retail loans | 90 days or more past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		0	0
Retail loans | Consumer borrower
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		9	8
Nonaccrual loans		23	32
Current loans		2,503	2,482
Total loans		2,535	2,522
Retail loans | Consumer borrower | 30 to 59 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		7	5
Retail loans | Consumer borrower | 60 to 89 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		2	3
Retail loans | Consumer borrower | 90 days or more past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		0	0
Retail loans | Real estate mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		18	10
Nonaccrual loans		36	39
Current loans		1,922	1,893
Total loans		1,976	1,942
Retail loans | Real estate mortgage | 30 to 59 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		8	7
Retail loans | Real estate mortgage | 60 to 89 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		10	3
Retail loans | Real estate mortgage | 90 days or more past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		0	0
Retail loans | Home equity | Consumer borrower
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		8	7
Nonaccrual loans		23	28
Current loans		1,765	1,765
Total loans		1,796	1,800
Retail loans | Home equity | Consumer borrower | 30 to 59 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		6	4
Retail loans | Home equity | Consumer borrower | 60 to 89 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		2	3
Retail loans | Home equity | Consumer borrower | 90 days or more past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		0	0
Retail loans | Other consumer | Consumer borrower
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		1	1
Nonaccrual loans		0	4
Current loans		738	717
Total loans		739	722
Retail loans | Other consumer | Consumer borrower | 30 to 59 days past due and still accruing
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		1	1
Retail loans | Other consumer | Consumer borrower | 60 to 89 days past due and still accruing
Financing Receivable, Recorded Investment, 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, Recorded Investment, Past Due [Line Items]
Loans past due and still accruing		$ 0	$ 0
[1]	Primarily loans to real estate developers.
[2]	Primarily loans to real estate developers.
[3]	Primarily loans secured by owner-occupied real estate.
[4]	Primarily loans secured by owner-occupied real estate.

Credit Quality And Allowance 48

Credit Quality And Allowance For Credit Losses (Loans By Credit Quality Indicator) (Details) - USD ($) $ in Millions		Jun. 30, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment [Line Items]
Total loans		$ 49,408	$ 49,088
Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	[1]	46,916	46,232
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	[2]	941	1,109
Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	[3]	1,058	1,165
Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	[4]	493	582
Business loans | Commercial borrower
Financing Receivable, Recorded Investment [Line Items]
Total loans		44,897	44,624
Business loans | Commercial borrower | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	[1]	42,479	41,847
Business loans | Commercial borrower | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	[2]	929	1,105
Business loans | Commercial borrower | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	[3]	1,055	1,161
Business loans | Commercial borrower | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	[4]	434	511
Business loans | Commercial borrower | Domestic loans
Financing Receivable, Recorded Investment [Line Items]
Total loans		31,449	30,994
Business loans | Commercial borrower | Domestic loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	[1]	29,492	28,616
Business loans | Commercial borrower | Domestic loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	[2]	661	944
Business loans | Commercial borrower | Domestic loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	[3]	917	989
Business loans | Commercial borrower | Domestic loans | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	[4]	379	445
Business loans | Commercial borrower | International loans
Financing Receivable, Recorded Investment [Line Items]
Total loans		1,145	1,258
Business loans | Commercial borrower | International loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	[1]	1,064	1,200
Business loans | Commercial borrower | International loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	[2]	57	22
Business loans | Commercial borrower | International loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	[3]	18	22
Business loans | Commercial borrower | International loans | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	[4]	6	14
Business loans | Real estate construction | Commercial borrower | Domestic loans
Financing Receivable, Recorded Investment [Line Items]
Total loans		2,857	2,869
Business loans | Real estate construction | Commercial borrower | Domestic loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	[1]	2,842	2,866
Business loans | Real estate construction | Commercial borrower | Domestic loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	[2]	15	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	[3]	0	3
Business loans | Real estate construction | Commercial borrower | Domestic loans | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	[4]	0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Commercial Real Estate business line
Financing Receivable, Recorded Investment [Line Items]
Total loans	[5],[6]	2,560	2,485
Business loans | Real estate construction | Commercial borrower | Domestic loans | Commercial Real Estate business line | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	[1],[6]	2,545	2,485
Business loans | Real estate construction | Commercial borrower | Domestic loans | Commercial Real Estate business line | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	[2],[6]	15	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Commercial Real Estate business line | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	[3],[6]	0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Commercial Real Estate business line | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	[4],[6]	0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Recorded Investment [Line Items]
Total loans	[7],[8]	297	384
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	[1],[8]	297	381
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	[2],[8]	0	0
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	[3],[8]	0	3
Business loans | Real estate construction | Commercial borrower | Domestic loans | Other business lines | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	[4],[8]	0	0
Business loans | Real estate mortgage | Commercial borrower | Domestic loans
Financing Receivable, Recorded Investment [Line Items]
Total loans		8,974	8,931
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	[1]	8,638	8,615
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	[2]	176	128
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	[3]	119	142
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	[4]	41	46
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line
Financing Receivable, Recorded Investment [Line Items]
Total loans	[5],[6]	1,826	2,018
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	[1],[6]	1,744	1,970
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	[2],[6]	66	19
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	[3],[6]	7	20
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	[4],[6]	9	9
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Recorded Investment [Line Items]
Total loans	[7],[8]	7,148	6,913
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Other business lines | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	[1],[8]	6,894	6,645
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Other business lines | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	[2],[8]	110	109
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Other business lines | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	[3],[8]	112	122
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Other business lines | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	[4],[8]	32	37
Business loans | Lease financing | Commercial borrower | Domestic loans
Financing Receivable, Recorded Investment [Line Items]
Total loans		472	572
Business loans | Lease financing | Commercial borrower | Domestic loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	[1]	443	550
Business loans | Lease financing | Commercial borrower | Domestic loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	[2]	20	11
Business loans | Lease financing | Commercial borrower | Domestic loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	[3]	1	5
Business loans | Lease financing | Commercial borrower | Domestic loans | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	[4]	8	6
Retail loans
Financing Receivable, Recorded Investment [Line Items]
Total loans		4,511	4,464
Retail loans | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	[1]	4,437	4,385
Retail loans | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	[2]	12	4
Retail loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	[3]	3	4
Retail loans | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	[4]	59	71
Retail loans | Consumer borrower
Financing Receivable, Recorded Investment [Line Items]
Total loans		2,535	2,522
Retail loans | Consumer borrower | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	[1]	2,507	2,485
Retail loans | Consumer borrower | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	[2]	2	1
Retail loans | Consumer borrower | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	[3]	3	4
Retail loans | Consumer borrower | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	[4]	23	32
Retail loans | Real estate mortgage
Financing Receivable, Recorded Investment [Line Items]
Total loans		1,976	1,942
Retail loans | Real estate mortgage | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	[1]	1,930	1,900
Retail loans | Real estate mortgage | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	[2]	10	3
Retail loans | Real estate mortgage | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	[3]	0	0
Retail loans | Real estate mortgage | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	[4]	36	39
Retail loans | Home equity | Consumer borrower
Financing Receivable, Recorded Investment [Line Items]
Total loans		1,796	1,800
Retail loans | Home equity | Consumer borrower | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	[1]	1,769	1,767
Retail loans | Home equity | Consumer borrower | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	[2]	1	1
Retail loans | Home equity | Consumer borrower | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	[3]	3	4
Retail loans | Home equity | Consumer borrower | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	[4]	23	28
Retail loans | Other consumer | Consumer borrower
Financing Receivable, Recorded Investment [Line Items]
Total loans		739	722
Retail loans | Other consumer | Consumer borrower | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	[1]	738	718
Retail loans | Other consumer | Consumer borrower | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	[2]	1	0
Retail loans | Other consumer | Consumer borrower | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	[3]	0	0
Retail loans | Other consumer | Consumer borrower | Nonaccrual
Financing Receivable, Recorded Investment [Line Items]
Total loans	[4]	$ 0	$ 4
[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.
[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 page F-56 in the Corporation's 2016 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 to real estate developers.
[7]	Primarily loans secured by owner-occupied real estate.
[8]	Primarily loans secured by owner-occupied real estate.

Credit Quality And Allowance 49

Credit Quality And Allowance For Credit Losses (Schedule Of Nonaccrual, Reduced-Rate Loans And Foreclosed Property) (Details) - USD ($) $ in Millions		Jun. 30, 2017	Dec. 31, 2016
Nonaccrual loans		$ 493	$ 582
Reduced-rate loans	[1]	8	8
Total nonperforming loans		501	590
Foreclosed property	[2]	18	17
Total nonperforming assets		519	607
Residential Real Estate
Foreclosed property		4	3
Business loans
Reduced-rate loans		0	0
Retail loans
Nonaccrual loans		59	71
Reduced-rate loans		$ 8	$ 8
[1]	There were no reduced-rate business loans at both June 30, 2017 and December 31, 2016. Reduced-rate retail loans were $8 million at both June 30, 2017 and December 31, 2016.
[2]	Included $4 million and $3 million of foreclosed residential real estate properties at June 30, 2017 and December 31, 2016, respectively.

Credit Quality And Allowance 50

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		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for loan losses	$ 17	$ 49	$ 33	$ 197
Total loans					$ 49,408	$ 49,088
Financing Receivable
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	708	724	730	634
Loan charge-offs	(39)	(54)	(83)	(131)
Recoveries on loans previously charged-off	21	12	32	37
Net loan charge-offs (recoveries)	(18)	(42)	(51)	(94)
Provision for loan losses	15	47	26	188
Foreign currency translation adjustment			0	1
Balance at end of period	705	729	705	729
As a percentage of total loans					1.43%		1.45%
Allowance for loan losses individually evaluated for impairment					$ 94		$ 112
Allowance for loan losses collectively evaluated for impairment					611		617
Total allowance for loan losses	708	724	730	634	705	730	729
Loans individually evaluated for impairment					550		672
Loans collectively evaluated for impairment					48,858		49,708
Total loans					$ 49,408		$ 50,380
Business loans | Financing Receivable
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	661	674	682	579
Loan charge-offs	(37)	(52)	(79)	(127)
Recoveries on loans previously charged-off	20	11	29	35
Net loan charge-offs (recoveries)	(17)	(41)	(50)	(92)
Provision for loan losses	17	49	29	194
Foreign currency translation adjustment			0	1
Balance at end of period	661	682	661	682
As a percentage of total loans					1.47%		1.48%
Allowance for loan losses individually evaluated for impairment					$ 93		$ 112
Allowance for loan losses collectively evaluated for impairment					568		570
Total allowance for loan losses	661	674	682	579	661	682	682
Loans individually evaluated for impairment					509		646
Loans collectively evaluated for impairment					44,388		45,354
Total loans					44,897		$ 46,000
Retail loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans					$ 4,511	4,464
Retail loans | Financing Receivable
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	47	50	48	55
Loan charge-offs	(2)	(2)	(4)	(4)
Recoveries on loans previously charged-off	1	1	3	2
Net loan charge-offs (recoveries)	(1)	(1)	(1)	(2)
Provision for loan losses	(2)	(2)	(3)	(6)
Foreign currency translation adjustment			0	0
Balance at end of period	44	47	44	47
As a percentage of total loans					0.98%		1.07%
Allowance for loan losses individually evaluated for impairment					$ 1		$ 0
Allowance for loan losses collectively evaluated for impairment					43		47
Total allowance for loan losses	$ 47	$ 50	$ 48	$ 55	44	$ 48	47
Loans individually evaluated for impairment					41		26
Loans collectively evaluated for impairment					4,470		4,354
Total loans					$ 4,511		$ 4,380

Credit Quality And Allowance 51

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		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for credit losses		$ 17	$ 49	$ 33	$ 197
Lending-related commitments
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period		46	46	41	45
Charge-offs on lending related commitments	[1]	0	(5)	0	(11)
Provision for credit losses		2	2	7	9
Balance at end of period		$ 48	$ 43	$ 48	$ 43
[1]	Charge-offs result from the sale of unfunded lending-related commitments.

Credit Quality And Allowance 52

Credit Quality And Allowance For Credit Losses (Individually Evaluated Impaired Loans) (Details) - USD ($) $ in Millions		Jun. 30, 2017	Dec. 31, 2016
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		$ 149	$ 131
Recorded investment in impaired loans with related allowance		401	483
Recorded investment total impaired loans		550	614
Unpaid principal balance		681	738
Related allowance for loan losses		94	89
Business loans | Commercial borrower
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		116	95
Recorded investment in impaired loans with related allowance		393	471
Recorded investment total impaired loans		509	566
Unpaid principal balance		638	683
Related allowance for loan losses		93	86
Business loans | Commercial borrower | Domestic loans
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		115	90
Recorded investment in impaired loans with related allowance		347	423
Recorded investment total impaired loans		462	513
Unpaid principal balance		569	608
Related allowance for loan losses		87	80
Business loans | Commercial borrower | International loans
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		0	3
Recorded investment in impaired loans with related allowance		6	11
Recorded investment total impaired loans		6	14
Unpaid principal balance		14	20
Related allowance for loan losses		1	2
Business loans | Real estate mortgage | Commercial borrower | Domestic loans
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		1	2
Recorded investment in impaired loans with related allowance		40	37
Recorded investment total impaired loans		41	39
Unpaid principal balance		55	55
Related allowance for loan losses		5	4
Business loans | Real estate 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]	0	0
Recorded investment in impaired loans with related allowance	[1]	7	7
Recorded investment total impaired loans	[1]	7	7
Unpaid principal balance	[1]	15	15
Related allowance for loan losses	[1]	4	1
Business loans | Real estate 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]	33	30
Recorded investment total impaired loans	[2]	34	32
Unpaid principal balance	[2]	40	40
Related allowance for loan losses	[2]	1	3
Retail loans
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance	[3]	33	36
Recorded investment in impaired loans with related allowance	[3]	8	12
Recorded investment total impaired loans	[3]	41	48
Unpaid principal balance	[3]	43	55
Related allowance for loan losses	[3]	1	3
Retail loans | Consumer borrower
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		14	17
Recorded investment in impaired loans with related allowance		0	3
Recorded investment total impaired loans		14	20
Unpaid principal balance		15	25
Related allowance for loan losses		0	1
Retail loans | Real estate mortgage
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		19	19
Recorded investment in impaired loans with related allowance		8	9
Recorded investment total impaired loans		27	28
Unpaid principal balance		28	30
Related allowance for loan losses		1	2
Retail loans | Home equity | Consumer borrower
Financing Receivable, Impaired [Line Items]
Recorded investment in impaired loans with no related allowance		12	15
Recorded investment in impaired loans with related allowance		0	0
Recorded investment total impaired loans		12	15
Unpaid principal balance		13	19
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		2	2
Recorded investment in impaired loans with related allowance		0	3
Recorded investment total impaired loans		2	5
Unpaid principal balance		2	6
Related allowance for loan losses		$ 0	$ 1
[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 53

Credit Quality And Allowance For Credit Losses (Average Individually Evaluated Impaired Loans And Related Interest Recognized) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		$ 563	$ 726	$ 580	$ 626
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		2	2	4	6
Business loans | Commercial borrower
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		522	701	537	598
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		2	2	4	6
Business loans | Commercial borrower | Domestic loans
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		473	639	487	537
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		2	2	4	6
Business loans | Commercial borrower | International loans
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		7	23	9	19
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		0	0	0	0
Business loans | Real estate mortgage | Commercial borrower | Domestic loans
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		42	39	41	42
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		0	0	0	0
Business loans | Real estate 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]	7	8	7	10
Individually Evaluated Impaired Loans Interest Income Recognized for the Period	[1]	0	0	0	0
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period	[2]	35	31	34	32
Individually Evaluated Impaired Loans Interest Income Recognized for the Period	[2]	0	0	0	0
Retail loans
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		41	25	43	28
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		0	0	0	0
Retail loans | Consumer borrower
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		14	14	16	16
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		0	0	0	0
Retail loans | Real estate mortgage
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		27	11	27	12
Individually Evaluated Impaired Loans Interest Income Recognized for the Period		0	0	0	0
Retail loans | Home equity | Consumer borrower
Financing Receivable, Impaired [Line Items]
Individually Evaluated Impaired Loans Average Balance for the Period		12	11	13	12
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		2	3	3	4
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 54

Credit Quality And Allowance For Credit Losses (Troubled Debt Restructurings By Type Of Modification) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period		$ 85	$ 40	$ 139	$ 148
Business loans | Commercial borrower
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period		84	39	136	145
Business loans | Commercial borrower | Domestic loans
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period		83	38	132	133
Business loans | Commercial borrower | International loans
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period				0	10
Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[1]	1	1	4	2
Retail loans
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period		1	1	3	3
Retail loans | Real estate mortgage
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period				0	2
Retail loans | Home equity | Consumer borrower
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[2]	1	1	3	1
Principal Deferrals
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[3]	48	20	$ 101	$ 110
Minimum period loan terms were extended				90 days	90 days
Principal Deferrals | Business loans | Commercial borrower
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[3]	48	19	$ 100	$ 109
Principal Deferrals | Business loans | Commercial borrower | Domestic loans
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[3]	47	18	96	107
Principal Deferrals | Business loans | Commercial borrower | International loans
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[3]			0	0
Principal Deferrals | Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[1],[3]	1	1	4	2
Principal Deferrals | Retail loans
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[3]	0	1	1	1
Principal Deferrals | Retail loans | Real estate mortgage
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[3]			0	0
Principal Deferrals | Retail loans | Home equity | Consumer borrower
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[2],[3]	0	1	1	1
Interest Rate Reductions
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period		1	0	2	2
Interest Rate Reductions | Business loans | Commercial borrower
Financing Receivable, Modifications [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, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period		0	0	0	0
Interest Rate Reductions | Business loans | Commercial borrower | International loans
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period				0	0
Interest Rate Reductions | Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[1]	0	0	0	0
Interest Rate Reductions | Retail loans
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period		1	0	2	2
Interest Rate Reductions | Retail loans | Real estate mortgage
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period				0	2
Interest Rate Reductions | Retail loans | Home equity | Consumer borrower
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[2]	1	0	2	0
AB Note Restructures
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[4]	36	20	36	36
AB Note Restructures | Business loans | Commercial borrower
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[4]	36	20	36	36
AB Note Restructures | Business loans | Commercial borrower | Domestic loans
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[4]	36	20	36	26
AB Note Restructures | Business loans | Commercial borrower | International loans
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[4]			0	10
AB Note Restructures | Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[1],[4]	0	0	0	0
AB Note Restructures | Retail loans
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[4]	0	0	0	0
AB Note Restructures | Retail loans | Real estate mortgage
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[4]			0	0
AB Note Restructures | Retail loans | Home equity | Consumer borrower
Financing Receivable, Modifications [Line Items]
Recorded balance of troubled debt restructuring modified during the period	[2],[4]	$ 0	$ 0	$ 0	$ 0
[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 days or more at or above contractual interest rates.
[4]	Loan restructurings whereby the original loan is restructured into two notes: an "A" note, which generally reflects the portion of the modified loan which is expected to be collected; and a "B" note, which is generally fully charged off.

Credit Quality And Allowance 55

Credit Quality And Allowance For Credit Losses Credit Quality And Allowance For Credit Losses (Troubled Debt Restructuring Subsequent Default) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Financing Receivable, Modifications [Line Items]
Mortgage Loans in Process of Foreclosure, Amount		$ 0		$ 0		$ 0
Principal Deferrals
Financing Receivable, Modifications [Line Items]
Balance		151	$ 247	151	$ 247
Subsequent default during period		0	22	0	29
Principal Deferrals | Business loans | Commercial borrower
Financing Receivable, Modifications [Line Items]
Balance		149	245	149	245
Subsequent default during period		0	22	0	29
Principal Deferrals | Business loans | Commercial borrower | Domestic loans
Financing Receivable, Modifications [Line Items]
Balance		141	233	141	233
Subsequent default during period		0	21	0	21
Principal Deferrals | Business loans | Commercial borrower | International loans
Financing Receivable, Modifications [Line Items]
Balance		0	1	0	1
Subsequent default during period		0	0	0	1
Principal Deferrals | Business loans | Real estate mortgage | Commercial borrower | Domestic loans
Financing Receivable, Modifications [Line Items]
Balance		8	11	8	11
Subsequent default during period		0	1	0	7
Principal Deferrals | Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Commercial Real Estate business line
Financing Receivable, Modifications [Line Items]
Balance	[1]	1	4	1	4
Subsequent default during period	[1]	0	1	0	1
Principal Deferrals | Business loans | Real estate mortgage | Commercial borrower | Domestic loans | Other business lines
Financing Receivable, Modifications [Line Items]
Balance	[2]	7	7	7	7
Subsequent default during period	[2]	0	0		6
Principal Deferrals | Retail loans | Home equity | Consumer borrower
Financing Receivable, Modifications [Line Items]
Balance	[3]	1	2	1	2
Subsequent default during period		$ 0	$ 0	$ 0	$ 0
[1]	Primarily loans to real estate developers.
[2]	Primarily loans secured by owner-occupied real estate.
[3]	Includes bankruptcy loans for which the court has discharged the borrower's obligation and the borrower has not reaffirmed the debt.

Derivative And Credit-Related56

Derivative And Credit-Related Financial Instruments (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair value of securities received as collateral for derivative assets	$ 11		$ 11
Cash received as collateral for derivative assets	77		77
Fair value of securities pledged as collateral for derivative liabilities	21		21
Cash posted as collateral for derivative liabilities	5		5
Aggregate fair value of all derivative instruments with credit-risk contingent features that were in a liability position	0		0
Net interest income generated by risk management fair value interest rate swaps	10	$ 16	20	$ 33
Net gain on interest rate fair value hedge ineffectiveness	0	0	0	(3)
Gain (loss) on foreign currency derivatives used as economic hedges	0	0	0
Net gain on open foreign currency positions	0	$ 1	0	$ 1
Allowance for credit losses on lending-related commitments	48		$ 48		$ 41
Allowance for credit losses on lending-related commitments, amount related to unused commitments to extend credit					29
Final year of expiration for outstanding letters of credit			2,023
Risk participation agreements covering standby and commercial letters of credit	250		$ 250		255
Standby and commercial letters of credit	3,500		3,500		3,700
Carrying value of standby and commercial letters of credit included in accrued expenses and other liabilities	47		47		44
Deferred fees on standby and commercial letters of credit included in accrued expenses and other liabilities	28		28		32
Allowance for credit losses on lending-related commitments, amount related to standby and commercial letters of credit	19		19		12
Notional amount of derivative credit risk participation agreements	577		577		458
Maximum estimated exposure to credit risk participation agreements assuming 100% default	$ 2		$ 2		$ 3
Weighted average remaining maturity of credit risk participation agreements, in years			2 years 5 months 26 days

Derivative And Credit-Related57

Derivative And Credit-Related Financial Instruments (Schedule Of Derivative Instruments) (Details) - USD ($) $ in Millions		Jun. 30, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	$ 20,721	$ 20,051
Fair Value of Gross Derivative Assets		236	407
Fair Value of Gross Derivative Liabilities		183	254
Derivative assets, Netting adjustment - Offsetting derivative liabilities		(54)	(84)
Derivative liabilities, Netting adjustment - Offsetting derivative assets		(54)	(84)
Derivative assets, Netting adjustment - Cash collateral received		(68)	(47)
Derivative liabilities, Netting adjustment, Cash collateral posted		(4)	(45)
Net derivative assets included in the consolidated balance sheets	[2]	114	276
Net derivative liabilities included in the consolidated balance sheets	[2]	125	125
Derivative asset, securities pledged as collateral		(10)	(19)
Derivative liability, securities pledged as collateral		(16)	(8)
Net derivative assets after deducting amounts not offset in the consolidated balance sheets		104	257
Net derivative liabilities after deducting amounts not offset in the consolidated balance sheets		109	117
Credit valuation adjustments for counterparty credit risk		5	5
Risk management purposes
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	2,978	2,992
Fair Value of Gross Derivative Assets		10	94
Fair Value of Gross Derivative Liabilities		4	6
Risk management purposes | Derivatives designated as hedging instruments | Fair Value Hedging | Interest rate swap
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1],[3]	2,275	2,275
Fair Value of Gross Derivative Assets	[3]	10	92
Fair Value of Gross Derivative Liabilities	[3]	0	4
Risk management purposes | Derivatives used as economic hedges | Foreign exchange spot, forwards and swaps
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	703	717
Fair Value of Gross Derivative Assets		0	2
Fair Value of Gross Derivative Liabilities		4	2
Customer-initiated and other activities
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	17,743	17,059
Fair Value of Gross Derivative Assets		226	313
Fair Value of Gross Derivative Liabilities		179	248
Customer-initiated and other activities | Interest rate contracts
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	14,257	13,323
Fair Value of Gross Derivative Assets		86	131
Fair Value of Gross Derivative Liabilities		47	77
Customer-initiated and other activities | Interest rate caps and floors written
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	627	436
Fair Value of Gross Derivative Assets		0	0
Fair Value of Gross Derivative Liabilities		0	1
Customer-initiated and other activities | Interest rate caps and floors purchased
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	627	436
Fair Value of Gross Derivative Assets		0	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],[3]	13,003	12,451
Fair Value of Gross Derivative Assets	[3]	86	130
Fair Value of Gross Derivative Liabilities	[3]	47	76
Customer-initiated and other activities | Energy contracts
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	1,903	2,227
Fair Value of Gross Derivative Assets		104	146
Fair Value of Gross Derivative Liabilities		102	144
Customer-initiated and other activities | Energy caps and floors written
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	297	419
Fair Value of Gross Derivative Assets		0	1
Fair Value of Gross Derivative Liabilities		19	31
Customer-initiated and other activities | Energy caps and floors purchased
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	297	419
Fair Value of Gross Derivative Assets		19	31
Fair Value of Gross Derivative Liabilities		0	1
Customer-initiated and other activities | Energy swaps
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	1,309	1,389
Fair Value of Gross Derivative Assets		85	114
Fair Value of Gross Derivative Liabilities		83	112
Customer-initiated and other activities | Foreign exchange spot, options and swaps
Derivatives, Fair Value [Line Items]
Notional/Contract Amount	[1]	1,583	1,509
Fair Value of Gross Derivative Assets		36	36
Fair Value of Gross Derivative Liabilities		$ 30	$ 27
[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 $5 million at both June 30, 2017 and December 31, 2016.
[3]	Due to clearinghouse rule changes, beginning January 1, 2017, variation margin payments are treated as settlements of derivative exposure rather than as collateral. As a result, these payments are now considered in determining the fair value of centrally cleared derivatives, resulting in centrally cleared derivatives having a fair value of approximately zero.

Derivative And Credit-Related58

Derivative And Credit-Related Financial Instruments (Schedule Of Weighted Average Maturity And Interest Rates On Risk Management Interest Rate Swaps) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended		12 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Gain (Loss) on Interest Rate Fair Value Hedge Ineffectiveness		$ 0	$ 0	$ 0	$ 3
Notional Amount	[1]	20,721		20,721		$ 20,051
Risk management purposes
Notional Amount	[1]	2,978		2,978		2,992
Medium- and long-term debt | Swaps - fair value - receive fixed/pay floating | Risk management purposes | Interest rate swap
Notional Amount		$ 2,275		$ 2,275		$ 2,275
Weighted Average Remaining Maturity				4 years 15 days		4 years 6 months 12 days
Weighted Average Receive Rate		3.69%		3.69%		3.69%
Weighted Average Pay Rate	[2]	1.98%		1.98%		1.80%
[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 are based on six-month LIBOR rates in effect at June 30, 2017 and December 31, 2016.

Derivative And Credit-Related59

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		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Net derivative gain recognized in income	$ 19	$ 16	$ 36	$ 28
Interest rate contracts | Other noninterest income
Derivative Instruments, Gain (Loss) [Line Items]
Net derivative gain recognized in income	7	6	13	8
Energy Related Derivative [Member] | Other noninterest income
Derivative Instruments, Gain (Loss) [Line Items]
Net derivative gain recognized in income	1	1	1	1
Foreign exchange contracts | Foreign exchange income
Derivative Instruments, Gain (Loss) [Line Items]
Net derivative gain recognized in income	$ 11	$ 9	$ 22	$ 19

Derivative And Credit-Related60

Derivative And Credit-Related Financial Instruments (Schedule Of Financial Instruments With Off-Balance Sheet Credit Risk) (Details) - Maximum - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Unused Commitments to Extend Credit
Loss contingency, estimate of possible loss, maximum	$ (25,299)	$ (26,991)
Commercial And Other | Unused Commitments to Extend Credit
Loss contingency, estimate of possible loss, maximum	(22,450)	(24,333)
Bankcard, Revolving Check Credit And Home Equity Loan Commitments | Unused Commitments to Extend Credit
Loss contingency, estimate of possible loss, maximum	(2,849)	(2,658)
Standby Letters Of Credit
Loss contingency, estimate of possible loss, maximum	(3,436)	(3,623)
Commercial Letters Of Credit
Loss contingency, estimate of possible loss, maximum	$ (40)	$ (46)

Derivative And Credit-Related61

Derivative And Credit-Related Financial Instruments (Summary Of Internally Classified Watch List Letters Of Credit) (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Total criticized standby and commercial letters of credit	$ 103	$ 135
As a percentage of total outstanding standby and commercial letters of credit	3.00%	3.70%

Variable Interest Entities (V62

Variable Interest Entities (VIEs) (Narrative) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Variable Interest Entity
Unfunded commitments to fund tax credit entities	$ 172
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	424
Other Tax Credit Entities
Variable Interest Entity
Exposure to loss as a result of involvement with VIEs	$ 7

Variable Interest Entities (V63

Variable Interest Entities (VIEs) (Impact Of VIEs On The Consolidated Statements Of Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Variable Interest Entity
Other noninterest income	$ 31	$ 29	$ 60	$ 46
Provision for income taxes	99	42	165	67
Variable Interest Entity
Variable Interest Entity
Other noninterest income	0	0	1	0
Provision for income taxes, amortization of LIHTC investments	16	16	32	32
Provision for income taxes	(6)	(5)	(11)	(11)
Low income housing tax credits | Variable Interest Entity
Variable Interest Entity
Provision for income taxes, affordable housing tax credits and other tax benefits	(16)	(15)	(31)	(31)
Other tax benefits related to tax credit entities | Variable Interest Entity
Variable Interest Entity
Provision for income taxes, affordable housing tax credits and other tax benefits	$ (6)	$ (6)	$ (12)	$ (12)

Medium- And Long-Term Debt (Nar

Medium- And Long-Term Debt (Narrative) (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Unamortized debt issuance cost	$ 6	$ 7
Subsidiaries
Debt Instrument [Line Items]
Blanket lien on real estate-related loans securing FHLB advances	15,600
Potential FHLB borrowing capacity	$ 3,500
Floating-rate FHLB advances | Subsidiaries
Debt Instrument [Line Items]
Weighted-average interest rate	1.13%

Medium- And Long-Term Debt (Sch

Medium- And Long-Term Debt (Schedule Of Medium- And Long-Term Debt) (Details) - USD ($) $ in Millions		6 Months Ended	12 Months Ended
		Jun. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Total medium- and long-term debt		$ 5,143	$ 5,160
Parent Company
Debt Instrument [Line Items]
Total medium- and long-term debt		607	604
Subsidiaries
Debt Instrument [Line Items]
Subordinated notes		1,066	1,073
Total medium- and long-term debt		4,536	4,556
3.80% subordinated notes due 2026 | Parent Company
Debt Instrument [Line Items]
Subordinated notes	[1]	$ 258	$ 256
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]	$ 349	$ 348
Stated interest rate		2.125%	2.125%
Maturity date		May 23, 2019	May 23, 2019
5.20% subordinated notes due 2017 | Subsidiaries
Debt Instrument [Line Items]
Subordinated notes	[1]	$ 502	$ 511
Stated interest rate		5.20%	5.20%
Maturity date		Aug. 22, 2017	Aug. 22, 2017
4.00% subordinated notes due 2025 | Subsidiaries
Debt Instrument [Line Items]
Subordinated notes	[1]	$ 351	$ 347
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]	$ 213	$ 215
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]	$ 670	$ 667
Stated interest rate		2.50%	2.50%
Maturity date		Jun. 2, 2020	Jun. 2, 2020
Floating-rate based on FHLB auction rate due 2026 | Subsidiaries
Debt Instrument [Line Items]
Federal Home Loan Bank advances		$ 2,800	$ 2,800
Weighted-average interest rate		1.13%
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 2026 | Subsidiaries | Maximum
Debt Instrument [Line Items]
Maturity date		May 20, 2026
6.0% - 6.4% fixed-rate notes due 2020 | Subsidiaries
Debt Instrument [Line Items]
Other notes		$ 0	$ 16
Maturity date		Jun. 30, 2020	Jun. 30, 2020
6.0% - 6.4% fixed-rate notes due 2020 | Subsidiaries | Minimum
Debt Instrument [Line Items]
Stated interest rate		6.00%	6.00%
6.0% - 6.4% fixed-rate notes due 2020 | Subsidiaries | Maximum
Debt Instrument [Line Items]
Stated interest rate		6.40%	6.40%
[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 Comprehensi66

Accumulated Other Comprehensive Loss (Schedule Of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Investment securities, Balance at beginning of period, net of tax	$ (33)	$ 9
Investment securities, Net unrealized holding gains arising during the period	21	191
Investment securities, Less: Provision for income taxes	8	70
Investment securities, Net unrealized holding gains arising during the period, net of tax	13	121
Investment securities, Net losses realized as a yield adjustment in interest on investment securities	(1)	(2)
Investment securities, Less: Benefit for income taxes	0	(1)
Investment securities, Reclassification adjustment for net losses realized as a yield adjustment included in net income, net of tax	(1)	(1)
Investment securities, Change in net unrealized gains on investment securities, net of tax	14	122
Investment securities, Balance at end of period, net of tax	(19)	131
Benefit plans, Balance at beginning of period, net of tax	(350)	(438)
Benefit plans, Amortization of actuarial net loss recognized in salaries and benefits expense	25	19
Benefit plans, Amortization of prior service credit recognized in salaries and benefits expense	(13)	0
Benefit plans, Amounts recognized in salaries and benefits expense	12	19
Benefit plans, Less: Provision for income taxes	4	7
Benefit plans, Change in defined benefit pension and other postretirement plans adjustment, net of tax	8	12
Benefit plans, Balance at end of period, net of tax	(342)	(426)
Total accumulated other comprehensive loss at end of period, net of tax	$ (361)	$ (295)	$ (383)

Net Income Per Common Share (Ba

Net Income Per Common Share (Basic And Diluted Net Income Per Common Share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Earnings Per Share [Abstract]
Net income	$ 203	$ 104	$ 405	$ 164
Income allocated to participating securities	1	1	3	2
Net income attributable to common shares	$ 202	$ 103	$ 402	$ 162
Basic average common shares	175	173	175	173
Basic net income per common share	$ 1.15	$ 0.60	$ 2.30	$ 0.94
Basic average common shares	175	173	175	173
Net effect of the assumed exercise of stock options	3	2	3	2
Net effect of the assumed exercise of warrants	1	2	2	2
Diluted average common shares	179	177	180	177
Diluted net income per common share	$ 1.13	$ 0.58	$ 2.24	$ 0.92

Net Income Per Common Share (Sc

Net Income Per Common Share (Schedule of Average Shares Excluded From Diluted Net Income Per Common Share Computation) (Details) - Stock Options - $ / shares shares in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Average outstanding options	0	2.6	0	4.8
Minimum
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Range of exercise prices		$ 46.68		$ 37.26
Maximum
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Range of exercise prices		$ 59.86		$ 59.86

Employee Benefit Plans Employee

Employee Benefit Plans Employee Benefit Plans (Net Periodic Defined Benefit Cost) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Defined Benefit Plan Disclosure [Line Items]
Net periodic defined benefit cost			$ (9)	$ 7
Qualified Defined Benefit Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 7	$ 8	14	16
Interest cost	19	23	39	46
Expected return on plan assets	(39)	(40)	(79)	(81)
Amortization of prior service (credit) cost	(4)	1	(9)	2
Amortization of net loss	10	8	21	16
Net periodic defined benefit cost	(7)	0	(14)	(1)
Non-Qualified Defined Benefit Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	1	1	2
Interest cost	2	3	4	5
Amortization of prior service (credit) cost	(2)	(1)	(4)	(2)
Amortization of net loss	2	1	4	3
Net periodic defined benefit cost	2	4	5	8
Postretirement Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Interest cost	0	1	1	2
Expected return on plan assets	0	(1)	(1)	(2)
Net periodic defined benefit cost	$ 0	$ 0	$ 0	$ 0

Income Taxes And Tax-Related 70

Income Taxes And Tax-Related Items Income Taxes And Tax-Related Items (Narrative) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Unrecognized tax benefits	$ 11	$ 15
Reasonably possible decrease in unrecognized tax benefits in next 12 months	1
Tax-related interest and penalties payable	9	7
Net deferred tax assets	224	217
Increase in net deferred tax assets	7
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, 2017
Maximum
Years state net operating loss carryforwards expire	Dec. 31, 2026

Contingent Liabilities (Narrati

Contingent Liabilities (Narrative) (Details) - USD ($) $ in Millions	Jan. 17, 2014	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Loss Contingencies [Line Items]
Legal fees		$ 5	$ 5	$ 10	$ 10
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		$ 28		$ 28
Butte Local Development v. Masters Group v. Comerica Bank
Loss Contingencies [Line Items]
Amount of damages awarded by the jury	$ 52

Restructuring Charges (Narrativ

Restructuring Charges (Narrative) (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)
Restructuring Cost and Reserve [Line Items]
Number of banking centers to be consolidated under restructuring plan	38
Restructuring charges	$ 14	$ 53	$ 25	$ 53
Business Bank
Restructuring Cost and Reserve [Line Items]
Restructuring charges	7	26	13	26
Retail Bank
Restructuring Cost and Reserve [Line Items]
Restructuring charges	4	19	8	19
Wealth Management
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 3	$ 8	$ 4	$ 8

Restructuring Charges (Schedule

Restructuring Charges (Schedule of Changes in Restructuring Reserves) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Restructuring Cost and Reserve [Line Items]
Balance at beginning of period		$ 13	$ 0	$ 18	$ 0
Restructuring charges		14	53	25	53
Payments		(14)	(3)	(27)	(3)
Adjustments for non-cash charges	[1]	(2)		(5)
Balance at end of period		11	50	11	50
Total restructuring charges incurred to date		118		$ 118
Expected completion date of restructuring activities				Dec. 31, 2018
Employee costs
Restructuring Cost and Reserve [Line Items]
Balance at beginning of period		7	0	$ 10	0
Restructuring charges		3	46	4	46
Payments		(4)	0	(8)	0
Adjustments for non-cash charges	[1]	0		0
Balance at end of period		6	46	6	46
Total restructuring charges incurred to date		56		56
Facilities costs
Restructuring Cost and Reserve [Line Items]
Balance at beginning of period		0	0	4	0
Restructuring charges		4	0	5	0
Payments		(4)	0	(9)	0
Adjustments for non-cash charges	[1]	0		0
Balance at end of period		0	0	0	0
Total restructuring charges incurred to date		20		20
Technology costs
Restructuring Cost and Reserve [Line Items]
Balance at beginning of period		3	0	0	0
Restructuring charges		6	0	12	0
Payments		(4)	0	(4)	0
Adjustments for non-cash charges	[1]	(2)		(5)
Balance at end of period		3	0	3	0
Total restructuring charges incurred to date		12		12
Other costs
Restructuring Cost and Reserve [Line Items]
Balance at beginning of period		3	0	4	0
Restructuring charges		1	7	4	7
Payments		(2)	(3)	(6)	(3)
Adjustments for non-cash charges	[1]	0		0
Balance at end of period		2	$ 4	2	$ 4
Total restructuring charges incurred to date		30		30
Minimum
Restructuring Cost and Reserve [Line Items]
Total expected restructuring charges	[2]	140		140
Minimum | Employee costs
Restructuring Cost and Reserve [Line Items]
Total expected restructuring charges	[2]	56		56
Minimum | Facilities costs
Restructuring Cost and Reserve [Line Items]
Total expected restructuring charges	[2]	30		30
Minimum | Technology costs
Restructuring Cost and Reserve [Line Items]
Total expected restructuring charges	[2]	20		20
Minimum | Other costs
Restructuring Cost and Reserve [Line Items]
Total expected restructuring charges	[2]	34		34
Maximum
Restructuring Cost and Reserve [Line Items]
Total expected restructuring charges	[2]	160		160
Maximum | Employee costs
Restructuring Cost and Reserve [Line Items]
Total expected restructuring charges	[2]	56		56
Maximum | Facilities costs
Restructuring Cost and Reserve [Line Items]
Total expected restructuring charges	[2]	35		35
Maximum | Technology costs
Restructuring Cost and Reserve [Line Items]
Total expected restructuring charges	[2]	35		35
Maximum | Other costs
Restructuring Cost and Reserve [Line Items]
Total expected restructuring charges	[2]	$ 34		$ 34
[1]	Adjustments for non-cash charges primarily include impairments of previously capitalized software costs.
[2]	Restructuring activities are expected to be substantially completed by 12/31/2018.

Business Segment Information (N

Business Segment Information (Narrative) (Details)	6 Months Ended
	Jun. 30, 2017segmentsmarkets
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			6 Months Ended
		Jun. 30, 2017		Jun. 30, 2016	Jun. 30, 2017		Jun. 30, 2016
Net interest income (expense)		$ 500		$ 445	$ 970		$ 892
Provision for credit losses		17		49	33		197
Noninterest income		276		268	547		512
Noninterest expenses		457		518	914		976
Provision (benefit) for income taxes		(99)		(42)	(165)		(67)
Net income (loss)		203		104	405		164
Net credit-related charge-offs (recoveries)		18		47	51		105
Assets, average		71,318		70,668	71,567		69,948
Loans, average		48,723		49,469	48,313		48,931
Deposits, average		$ 57,128		$ 56,521	$ 57,452		$ 56,615
Return on average assets	[1],[2]	1.14%		0.59%	1.14%		0.47%
Efficiency ratio	[3],[4]	58.63%		72.43%	60.10%		69.25%
Business Bank
Net interest income (expense)		$ 336		$ 349	$ 668		$ 706
Provision for credit losses		12		46	22		197
Noninterest income		152		143	296		279
Noninterest expenses		196		221	393		427
Provision (benefit) for income taxes		(100)		(74)	(192)		(118)
Net income (loss)		180		151	357		243
Net credit-related charge-offs (recoveries)		10		42	40		99
Assets, average		38,853		39,983	38,474		39,574
Loans, average		37,580		38,574	37,169		38,068
Deposits, average		$ 28,748		$ 28,441	$ 29,196		$ 28,778
Return on average assets	[1]	1.85%		1.52%	1.87%		1.24%
Efficiency ratio	[3]	40.19%		44.75%	40.75%		43.28%
Retail Bank
Net interest income (expense)		$ 162		$ 154	$ 322		$ 309
Provision for credit losses		5		1	17		4
Noninterest income		48		48	96		92
Noninterest expenses		180		205	359		385
Provision (benefit) for income taxes		(9)		2	(15)		(3)
Net income (loss)		16		(2)	27		9
Net credit-related charge-offs (recoveries)		9		1	14		3
Assets, average		6,487		6,558	6,506		6,551
Loans, average		5,865		5,879	5,880		5,873
Deposits, average		$ 23,935		$ 23,546	$ 23,866		$ 23,328
Return on average assets	[1]	0.27%		(0.04%)	0.22%		0.07%
Efficiency ratio	[3]	84.79%		101.58%	85.39%		95.42%
Wealth Management
Net interest income (expense)		$ 42		$ 42	$ 83		$ 85
Provision for credit losses		(2)		3	(3)		(2)
Noninterest income		64		62	128		120
Noninterest expenses		71		81	141		154
Provision (benefit) for income taxes		(14)		(7)	(27)		(19)
Net income (loss)		23		13	46		34
Net credit-related charge-offs (recoveries)		(1)		4	(3)		3
Assets, average		5,432		5,215	5,419		5,189
Loans, average		5,278		5,016	5,264		4,990
Deposits, average		$ 4,106		$ 4,213	$ 4,042		$ 4,192
Return on average assets	[1]	1.76%		0.99%	1.73%		1.32%
Efficiency ratio	[3]	66.44%		78.22%	66.81%		75.15%
Finance
Net interest income (expense)		$ (49)		$ (105)	$ (120)		$ (218)
Provision for credit losses		0		0	0		0
Noninterest income		10		10	21		21
Noninterest expenses		(1)		0	(2)		(1)
Provision (benefit) for income taxes		17		36	41		74
Net income (loss)		(21)		(59)	(56)		(122)
Net credit-related charge-offs (recoveries)		0		0	0		0
Assets, average		13,936		13,927	13,940		13,858
Loans, average		0		0	0		0
Deposits, average		156		50	149		73
Other
Net interest income (expense)		9		5	17		10
Provision for credit losses		2		(1)	(3)		(2)
Noninterest income		2		5	6		0
Noninterest expenses		11		11	23		11
Provision (benefit) for income taxes		7	[5]	1	28	[6]	(1)
Net income (loss)		5		1	31		0
Net credit-related charge-offs (recoveries)		0		0	0		0
Assets, average		6,610		4,985	7,228		4,776
Loans, average		0		0	0		0
Deposits, average		183		$ 271	199		$ 244
Accounting Standards Update 2016-09
Provision (benefit) for income taxes		$ (5)			$ (29)
[1]	Return on average assets is calculated based on the greater of average assets or average liabilities and attributed equity.
[2]	Return on average assets is calculated based on the greater of average assets or average liabilities and attributed equity.
[3]	Noninterest expenses as a percentage of the sum of net interest income (fully taxable equivalent basis) and noninterest income excluding net securities gains (losses).
[4]	Noninterest expenses as a percentage of the sum of net interest income (fully taxable equivalent basis) and noninterest income excluding net securities gains.
[5]	Includes tax benefit of $5 million from employee stock transactions.
[6]	Includes tax benefit of $29 million from employee stock transactions.

Business Segment Information (M

Business Segment Information (Market Segment Financial Results) (Details) - USD ($) $ in Millions		3 Months Ended			6 Months Ended
		Jun. 30, 2017		Jun. 30, 2016	Jun. 30, 2017		Jun. 30, 2016
Net interest income (expense)		$ 500		$ 445	$ 970		$ 892
Provision for credit losses		17		49	33		197
Noninterest income		276		268	547		512
Noninterest expenses		457		518	914		976
Provision (benefit) for income taxes		(99)		(42)	(165)		(67)
Net income (loss)		203		104	405		164
Net credit-related charge-offs (recoveries)		18		47	51		105
Assets, average		71,318		70,668	71,567		69,948
Loans, average		48,723		49,469	48,313		48,931
Deposits, average		$ 57,128		$ 56,521	$ 57,452		$ 56,615
Return on average assets	[1],[2]	1.14%		0.59%	1.14%		0.47%
Efficiency ratio	[3],[4]	58.63%		72.43%	60.10%		69.25%
Michigan
Net interest income (expense)		$ 167		$ 164	$ 337		$ 338
Provision for credit losses		(2)		3	(4)		(3)
Noninterest income		81		81	164		157
Noninterest expenses		145		159	295		310
Provision (benefit) for income taxes		(38)		(28)	(75)		(63)
Net income (loss)		67		55	135		125
Net credit-related charge-offs (recoveries)		(1)		0	(4)		5
Assets, average		13,371		13,142	13,313		13,194
Loans, average		12,712		12,502	12,650		12,560
Deposits, average		$ 21,698		$ 21,519	$ 21,923		$ 21,594
Return on average assets	[2]	1.20%		1.00%	1.20%		1.12%
Efficiency ratio	[4]	58.14%		64.65%	58.75%		62.31%
California
Net interest income (expense)		$ 178		$ 176	$ 349		$ 351
Provision for credit losses		24		18	45		12
Noninterest income		45		38	86		76
Noninterest expenses		98		120	194		224
Provision (benefit) for income taxes		(40)		(27)	(76)		(70)
Net income (loss)		61		49	120		121
Net credit-related charge-offs (recoveries)		8		17	18		25
Assets, average		18,446		18,155	18,203		17,926
Loans, average		18,194		17,865	17,938		17,653
Deposits, average		$ 17,344		$ 16,967	$ 17,294		$ 16,823
Return on average assets	[2]	1.33%		1.08%	1.33%		1.36%
Efficiency ratio	[4]	43.82%		55.73%	44.50%		52.11%
Texas
Net interest income (expense)		$ 113		$ 117	$ 226		$ 238
Provision for credit losses		(15)		32	(24)		201
Noninterest income		33		32	65		62
Noninterest expenses		94		113	188		213
Provision (benefit) for income taxes		(25)		(2)	(47)		39
Net income (loss)		42		2	80		(75)
Net credit-related charge-offs (recoveries)		5		31	27		78
Assets, average		10,481		11,287	10,518		11,291
Loans, average		10,015		10,841	10,062		10,802
Deposits, average		$ 9,632		$ 10,052	$ 9,871		$ 10,214
Return on average assets	[2]	1.52%		0.07%	1.44%		(1.28%)
Efficiency ratio	[4]	64.37%		75.89%	64.58%		70.95%
Other Markets
Net interest income (expense)		$ 82		$ 88	$ 161		$ 173
Provision for credit losses		8		(3)	19		(11)
Noninterest income		105		102	205		196
Noninterest expenses		110		115	216		219
Provision (benefit) for income taxes		(20)		(22)	(36)		(46)
Net income (loss)		49		56	95		115
Net credit-related charge-offs (recoveries)		6		(1)	10		(3)
Assets, average		8,474		9,172	8,365		8,903
Loans, average		7,802		8,261	7,663		7,916
Deposits, average		$ 8,115		$ 7,662	$ 8,016		$ 7,667
Return on average assets	[2]	2.24%		2.45%	2.19%		2.60%
Efficiency ratio	[4]	58.45%		60.77%	58.87%		59.45%
Finance & Other
Net interest income (expense)		$ (40)		$ (100)	$ (103)		$ (208)
Provision for credit losses		2		(1)	(3)		(2)
Noninterest income		12		15	27		21
Noninterest expenses		10		11	21		10
Provision (benefit) for income taxes		24	[5]	37	69	[6]	73
Net income (loss)		(16)		(58)	(25)		(122)
Net credit-related charge-offs (recoveries)		0		0	0		0
Assets, average		20,546		18,912	21,168		18,634
Loans, average		0		0	0		0
Deposits, average		339		$ 321	348		$ 317
Accounting Standards Update 2016-09
Provision (benefit) for income taxes		$ (5)			$ (29)
[1]	Return on average assets is calculated based on the greater of average assets or average liabilities and attributed equity.
[2]	Return on average assets is calculated based on the greater of average assets or average liabilities and attributed equity.
[3]	Noninterest expenses as a percentage of the sum of net interest income (fully taxable equivalent basis) and noninterest income excluding net securities gains (losses).
[4]	Noninterest expenses as a percentage of the sum of net interest income (fully taxable equivalent basis) and noninterest income excluding net securities gains.
[5]	Includes tax benefit of $5 million from employee stock transactions.
[6]	Includes tax benefit of $29 million from employee stock transactions.