Regions Financial (RF) 10-K 26 Feb 18 2017 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2017	Feb. 22, 2018	Jun. 30, 2017
Document Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Trading Symbol	RF
Entity Registrant Name	REGIONS FINANCIAL CORP
Entity Central Index Key	1,281,761
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		1,122,565,313
Entity Public Float			$ 11,537,313,844

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions		Dec. 31, 2017	Dec. 31, 2016
Assets
Cash and due from banks		$ 2,012	$ 1,853
Interest-bearing deposits in other banks		1,899	3,583
Federal funds sold and securities purchased under agreements to resell		70	15
Trading account securities		189	124
Securities held to maturity		1,658	1,362
Securities available for sale		23,628	23,781
Loans held for sale		348	718
Loans, net of unearned income	[1]	79,947	80,095
Allowance for loan losses		(934)	(1,091)
Net loans		79,013	79,004
Other earning assets		1,477	1,644
Premises and equipment, net		2,064	2,096
Interest receivable		337	319
Goodwill		4,904	4,904
Residential mortgage servicing rights at fair value		336	324
Other identifiable intangible assets		177	221
Other assets		6,182	6,020
Total assets		124,294	125,968
Deposits:
Non-interest-bearing		36,127	36,046
Interest-bearing		60,762	62,989
Total deposits		96,889	99,035
Borrowed funds:
Other short-term borrowings		500	0
Total short-term borrowings		500	0
Long-term borrowings		8,132	7,763
Total borrowed funds		8,632	7,763
Other liabilities		2,581	2,506
Total liabilities		108,102	109,304
Stockholders’ equity:
Preferred stock		820	820
Common stock		12	13
Additional paid-in capital		15,858	17,092
Retained earnings		1,628	666
Treasury stock, at cost		(1,377)	(1,377)
Accumulated other comprehensive income (loss), net		(749)	(550)
Total stockholders’ equity		16,192	16,664
Total liabilities and stockholders’ equity		$ 124,294	$ 125,968
[1]	Loans are presented net of unearned income, unamortized discounts and premiums and net deferred loan costs of $43 million and $141 million at December 31, 2017 and 2016, respectively.

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Securities held to maturity, estimated fair value	$ 1,667	$ 1,369
Loans held for sale, at fair value	$ 325	$ 447
Common stock, par or stated value per share	$ 0.01	$ 0.01
Common stock, shares authorized	3,000,000,000	3,000,000,000
Common stock, shares, issued	1,175,327,565	1,255,839,866
Treasury stock, shares	41,259,320	41,259,319
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, par value per share	$ 1	$ 1
Noncumulative Preferred Stock [Member]
Preferred stock, liquidation preference per share	$ 1,000	$ 1,000
Preferred stock, shares issued	1,000,000	1,000,000

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Millions, $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Interest income, including other financing income on:
Loans, including fees		$ 3,228	$ 3,066	$ 2,942
Securities - taxable		600	566	564
Loans held for sale		16	16	16
Trading account securities		4	5	5
Other earning assets		46	36	43
Operating lease assets		94	125	33
Total interest income, including other financing income		3,988	3,814	3,603
Interest expense on:
Deposits		156	117	109
Short-term borrowings		5	0	1
Long-term borrowings		212	196	158
Total interest expense		373	313	268
Depreciation expense on operating lease assets		75	103	28
Total interest expense and depreciation expense on operating lease assets		448	416	296
Net interest income and other financing income		3,540	3,398	3,307
Provision for loan losses		150	262	241
Net interest income and other financing income after provision for loan losses		3,390	3,136	3,066
Non-interest income:
Service charges on deposit accounts		683	664	662
Card and ATM fees		417	402	364
Investment management and trust fee income		230	213	202
Mortgage income		149	173	162
Securities gains, net		22	6	29
Other		604	695	652
Total non-interest income		2,105	2,153	2,071
Non-interest expense:
Salaries and employee benefits		1,954	1,913	1,883
Net occupancy expense		345	348	361
Furniture and equipment expense		330	317	303
Other		995	1,039	1,060
Total non-interest expense		3,624	3,617	3,607
Income from continuing operations before income taxes		1,871	1,672	1,530
Income tax expense	[1],[2]	614	514	455
Income from continuing operations		1,257	1,158	1,075
Discontinued operations:
Income (loss) from discontinued operations before income taxes		8	8	(22)
Income tax expense (benefit)		2	3	(9)
Income (loss) from discontinued operations, net of tax		6	5	(13)
Net income		1,263	1,163	1,062
Net income from continuing operations available to common shareholders		1,193	1,094	1,011
Net income available to common shareholders		$ 1,199	$ 1,099	$ 998
Weighted-average number of shares outstanding:
Basic		1,186	1,255	1,325
Diluted		1,198	1,261	1,334
Earnings per common share from continuing operations:
Basic	[3]	$ 1.01	$ 0.87	$ 0.76
Diluted	[3]	1	0.87	0.76
Earnings per common share:
Basic	[3]	1.01	0.87	0.75
Diluted	[3]	1	0.87	0.75
Cash dividends declared per common share		$ 0.315	$ 0.255	$ 0.23
[1]	Income tax expense includes amortization of affordable housing investments of $160 million (including $23 million due to impact of Tax Reform), $117 million and $103 million for 2017, 2016 and 2015, respectively. Income tax expense for 2015 includes a benefit of $15 million related to an improved methodology implemented to estimate the effective state tax rate.
[2]	The table above does not include total income tax expense (benefit) from discontinued operations of $2 million, $3 million, and $(9) million in 2017, 2016 and 2015, respectively. The deferred income tax expense reflected in discontinued operations was $1 million, $18 million and $46 million in 2017, 2016 and 2015, respectively.
[3]	Certain per share amounts may not appear to reconcile due to rounding.

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 1,263	$ 1,163	$ 1,062
Unrealized losses on securities transferred to held to maturity:
Unrealized losses on securities transferred to held to maturity during the period, net of tax	0	0	0
Less: Reclassification Adjustments for Amortization of Unrealized Losses on Securities Transferred to Held to Maturity, Net of Tax	(6)	(14)	(8)
Net change in unrealized losses on securities transferred to held to maturity, net of tax	6	14	8
Unrealized gains (losses) on securities available for sale:
Unrealized holding gains (losses) arising during the period on securities available for sale, net of tax	0	(92)	(166)
Less: reclassification adjustments for securities gains (losses) realized in net income (net of tax)	12	4	19
Net change in unrealized gains (losses) on securities available for sale, net of tax	(12)	(96)	(185)
Unrealized gains (losses) on derivative instruments designated as cash flow hedges:
Unrealized holding gains (losses) on derivatives arising during the period (net of tax)	2	25	137
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax	53	89	95
Net change in unrealized gains (losses) on derivative instruments, net of tax	(51)	(64)	42
Defined benefit pension plans and other post employment benefits:
Net actuarial gains (losses) arising during the period (net of tax)	(40)	(46)	(38)
Less: reclassification adjustments for amortization of actuarial loss and prior service cost realized in net income (net of tax)	(31)	(22)	(31)
Net change from defined benefit pension plans and other post employment benefits, net of tax	(9)	(24)	(7)
Other comprehensive income (loss), net of tax	(66)	(170)	(142)
Comprehensive income	$ 1,197	$ 993	$ 920

CONSOLIDATED STATEMENTS OF COM6

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Unrealized losses on securities transferred to held to maturity during the period, tax	$ 0	$ 0	$ 0
Amortization of unrealized losses on securities transferred to held to maturity, tax	(4)	(8)	(6)
Unrealized holding gains (losses) on available for sale securities, tax	(14)	(57)	(103)
Reclassification adjustments for securities gains (losses) realized in net income, tax	7	2	10
Unrealized holding gains on derivatives, tax	(2)	15	82
Reclassification adjustments for derivative gains (losses) realized in net income, tax	33	54	58
Net actuarial gains and losses arising during the period, tax	(13)	(27)	(21)
Reclassification adjustments for amortization of actuarial loss and prior service cost realized in net income, and other, tax	$ (17)	$ (12)	$ (17)

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) shares in Millions, $ in Millions	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings (Deficit) [Member]	Treasury Stock, At Cost [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Beginning Balance Outstanding (shares) at Dec. 31, 2014		1	1,354
Beginning Balance at Dec. 31, 2014	$ 16,873	$ 884	$ 14	$ 18,767	$ (1,177)	$ (1,377)	$ (238)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,062				1,062
Other comprehensive income (loss), net of tax	(142)						(142)
Cash dividends declared	(304)			(304)
Preferred stock dividends	(64)	$ (64)
Impact of share repurchase, shares			(63)
Impact of share repurchase, value	(623)		$ (1)	(622)
Impact of stock transactions under compensation plans, net and other, shares			6
Impact of stock transactions under compensation plans, net and other	42			42
Ending Balance Outstanding (shares) at Dec. 31, 2015		1	1,297
Ending Balance at Dec. 31, 2015	16,844	$ 820	$ 13	17,883	(115)	(1,377)	(380)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,163				1,163
Other comprehensive income (loss), net of tax	(170)						(170)
Cash dividends declared	(318)			0	(318)
Preferred stock dividends	(64)	$ 0			(64)
Impact of share repurchase, shares			(89)
Impact of share repurchase, value	(839)		$ 0	(839)
Impact of stock transactions under compensation plans, net and other, shares			6
Impact of stock transactions under compensation plans, net and other	48			48
Ending Balance Outstanding (shares) at Dec. 31, 2016		1	1,214
Ending Balance at Dec. 31, 2016	16,664	$ 820	$ 13	17,092	666	(1,377)	(550)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,263				1,263
Other comprehensive income (loss), net of tax	(66)						(66)
Reclassification of the Tax Reform related revaluation of deferred tax items within AOCI	0				133		(133)
Cash dividends declared	(370)			0	(370)
Preferred stock dividends	$ (64)	$ 0			(64)
Impact of share repurchase, shares	(65.7)		(85)
Impact of share repurchase, value	$ (1,275)		$ (1)	(1,274)
Impact of stock transactions under compensation plans, net and other, shares			4
Impact of stock transactions under compensation plans, net and other	40			40
Ending Balance Outstanding (shares) at Dec. 31, 2017		1	1,133
Ending Balance at Dec. 31, 2017	$ 16,192	$ 820	$ 12	$ 15,858	$ 1,628	$ (1,377)	$ (749)

CONSOLIDATED STATEMENTS OF CHA8

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Stockholders' Equity [Abstract]
Cash dividend declared (in dollars per share)	$ 0.315	$ 0.255	$ 0.23

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating activities:
Net income	$ 1,263	$ 1,163	$ 1,062
Adjustments to reconcile net income to net cash from operating activities:
Provision for loan losses	150	262	241
Depreciation, amortization and accretion, net	537	574	523
Securities (gains) losses, net	(22)	(6)	(29)
Deferred income tax expense	209	67	201
Originations and purchases of loans held for sale	(3,571)	(3,756)	(2,560)
Proceeds from sales of loans held for sale	4,053	3,700	2,755
(Gain) loss on sale of loans, net	(118)	(124)	(87)
(Gain) loss on early extinguishment of debt	0	14	43
Net change in operating assets and liabilities:
Trading account securities	(64)	19	(37)
Other earning assets	92	(95)	(200)
Interest receivable and other assets	(405)	(219)	12
Other liabilities	110	189	(449)
Other	47	180	124
Net cash from operating activities	2,281	1,968	1,599
Investing activities:
Proceeds from maturities of securities held to maturity	196	591	229
Proceeds from sales of securities available for sale	882	1,965	3,138
Proceeds from maturities of securities available for sale	3,649	4,420	3,890
Proceeds from sale of trading account securities	50	0	0
Purchases of securities available for sale	(4,580)	(7,874)	(7,819)
Purchases of securities held to maturity	(494)	0	0
Proceeds from sales of loans	25	182	76
Purchases of loans	(238)	(985)	(1,127)
Purchases of mortgage servicing rights	(41)	(64)	(4)
Net change in loans	(84)	1,339	(4,138)
Net purchases of other assets	(150)	(205)	(369)
Net cash from investing activities	(785)	(631)	(6,124)
Financing activities:
Net change in deposits	(2,146)	605	4,230
Net change in short-term borrowings	500	(10)	(2,243)
Proceeds from long-term borrowings	6,649	3,357	5,996
Payments on long-term borrowings	(6,255)	(3,916)	(1,142)
Cash dividends on common stock	(346)	(317)	(304)
Cash dividends on preferred stock	(64)	(64)	(64)
Repurchase of common stock	(1,275)	(839)	(623)
Taxes paid related to net share settlement of equity awards	(22)	(14)	(27)
Other	(7)	(2)	12
Net cash from financing activities	(2,966)	(1,200)	5,835
Net change in cash and cash equivalents	(1,470)	137	1,310
Cash and cash equivalents at beginning of year	5,451	5,314	4,004
Cash and cash equivalents at end of year	$ 3,981	$ 5,451	$ 5,314

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Regions Financial Corporation (“Regions” or the “Company”) provides a full range of banking and bank-related services to individual and corporate customers through its subsidiaries and branch offices located primarily in Alabama, Arkansas, Florida, Georgia, Illinois, Indiana, Iowa, Kentucky, Louisiana, Mississippi, Missouri, North Carolina, South Carolina, Tennessee, and Texas. The Company is subject to competition from other financial institutions, is subject to the regulations of certain government agencies and undergoes periodic examinations by certain of those regulatory authorities. The accounting and reporting policies of Regions and the methods of applying those policies that materially affect the consolidated financial statements conform with accounting principles generally accepted in the United States (“GAAP”) and with general financial services industry practices. In preparing the financial statements, management is required to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the balance sheet dates and revenues and expenses for the periods presented. Actual results could differ from the estimates and assumptions used in the consolidated financial statements including, but not limited to, the estimates and assumptions related to the allowance for credit losses, fair value measurements, intangibles, residential MSRs and income taxes. Regions has evaluated all subsequent events for potential recognition and disclosure through the filing date of this Annual Report on Form 10-K. Certain amounts in prior period financial statements have been reclassified to conform to the current period presentation, except as otherwise noted. These reclassifications are immaterial and have no effect on net income, comprehensive income (loss), total assets or total stockholders’ equity as previously reported. BASIS OF PRESENTATION AND PRINCIPLES OF CONSOLIDATION The consolidated financial statements include the accounts of Regions, its subsidiaries and certain VIEs. Significant intercompany balances and transactions have been eliminated. Regions considers a voting rights entity to be a subsidiary and consolidates it if Regions has a controlling financial interest in the entity. VIEs are consolidated if Regions has the power to direct the activities of the VIE that significantly impact financial performance and has the obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE (i.e., Regions is the primary beneficiary). The determination of whether Regions is the primary beneficiary of a VIE is reassessed on an ongoing basis. Investments in companies which are not VIEs but in which Regions has significant influence over the operating and financing decisions, are accounted for using the equity method of accounting. Investments in VIEs, where Regions is not the primary beneficiary of a VIE, are accounted for using either the proportional amortization method or the equity method of accounting. These investments are included in other assets in the consolidated balance sheets. The maximum potential exposure to losses relative to investments in VIEs is generally limited to the sum of the outstanding balance, future funding commitments and any related loans to the entity. Loans to these entities are underwritten in substantially the same manner as are other loans and are generally secured. Refer to Note 2 for additional disclosures regarding Regions’ significant VIEs. Unconsolidated equity investments that do not meet the criteria to be accounted for under the equity method are accounted for under the cost method. Cost method investments are included in other assets in the consolidated balance sheets and dividends received or receivable from these investments are included as a component of other non-interest income in the consolidated statements of income. DISCONTINUED OPERATIONS On January 11, 2012, Regions entered into an agreement to sell Morgan Keegan and related affiliates. The transaction closed on April 2, 2012. Results of operations for the entities sold are presented separately as discontinued operations for all periods presented on the consolidated statements of income. Other expenses related to the transaction are also included in discontinued operations. See Note 3 and Note 24 for further discussion. CASH EQUIVALENTS AND CASH FLOWS Cash equivalents represent assets that can be converted into cash immediately. At Regions, these assets include cash and due from banks, interest-bearing deposits in other banks, and federal funds sold and securities purchased under agreements to resell. Cash flows from loans, either originated or acquired, are classified at that time according to management’s intent to either sell or hold the loan for the foreseeable future. When management’s intent is to sell the loan, the cash flows of that loan are presented as operating cash flows. When management’s intent is to hold the loan for the foreseeable future, the cash flows of that loan are presented as investing cash flows. The following table summarizes supplemental cash flow information for the years ended December 31 : 2017 2016 2015 (In millions) Cash paid during the period for: Interest on deposits and borrowings $ 363 $ 299 $ 268 Income taxes, net 181 314 129 Non-cash transfers: Operating leases transferred from loans — — 879 Loans held for sale and loans transferred to other real estate 80 100 156 Loans transferred to loans held for sale 41 247 69 Loans held for sale transferred to loans 8 5 3 Properties transferred to held for sale 33 53 38 Loans settled with trading account securities 33 — — Operating lease assets settled with trading account securities 15 — — SECURITIES PURCHASED UNDER AGREEMENTS TO RESELL AND SECURITIES SOLD UNDER AGREEMENTS TO REPURCHASE Securities purchased under agreements to resell and securities sold under agreements to repurchase are treated as collateralized financing transactions. It is Regions’ policy to take possession of securities purchased under resell agreements either through direct delivery or a tri-party agreement. TRADING ACCOUNT SECURITIES Trading account securities, which are primarily held for employee benefit purposes as a funding mechanism for related liabilities, consist of debt and marketable equity securities and are carried at estimated fair value. See the “Fair Value Measurements” section below for discussion of determining fair value. Gains and losses, both realized and unrealized, are included in other non-interest income. SECURITIES Management determines the appropriate accounting classification of debt and equity securities at the time of purchase, based on intent, and periodically re-evaluates such designations. Debt securities are classified as securities held to maturity when the Company has the intent and ability to hold the securities to maturity. Securities held to maturity are presented at amortized cost. Debt securities not classified as securities held to maturity or trading account securities, and marketable equity securities not classified as trading account securities are classified as securities available for sale. Securities available for sale are presented at estimated fair value with changes in unrealized gains and losses, net of taxes, reported as a component of accumulated other comprehensive income (loss). See the “Fair Value Measurements” section below for discussion of determining fair value. The amortized cost of debt securities classified as securities held to maturity and securities available for sale is adjusted for amortization of premiums and accretion of discounts to maturity, or in the case of mortgage-backed securities, over the estimated life of the security, using the interest method. Such amortization or accretion is included in interest income on securities. Realized gains and losses are included in net securities gains (losses). The cost of securities sold is based on the specific identification method. The Company reviews its securities portfolio on a regular basis to determine if there are any conditions indicating that a security has other-than-temporary impairment. Factors considered in this determination include the length of time and the extent to which the market value has been below cost for equity securities. For debt securities, factors include the credit standing of the issuer, whether the Company expects to receive all scheduled principal and interest payments, Regions’ intent to sell and whether it is more likely than not that the Company will have to sell the security before its market value recovers. For debt securities, activity related to the credit loss component of other-than-temporary impairment is recognized in earnings as part of net securities gains (losses). Additionally, the Company recognizes impairment of available for sale equity securities when the cost basis is above the highest traded price within the past six months; the cost basis of the securities is adjusted to current estimated fair value with the entire offset recorded in the statement of income. Refer to Note 4 for further detail and information on securities. LOANS HELD FOR SALE Regions’ loans held for sale include commercial loans, investor real estate loans and residential real estate mortgage loans. Loans held for sale are recorded at either estimated fair value, if the fair value option is elected, or the lower of cost or estimated fair value. Regions has elected to account for residential real estate mortgages originated with the intent to sell at fair value. Intent is established for these conforming residential real estate mortgage loans when Regions enters into an interest rate lock commitment. Gains and losses on these residential mortgage loans held for sale for which the fair value option has been elected are included in mortgage income. Certain commercial mortgage loans held for sale where management has elected the fair value option are recorded at fair value. Gains and losses on commercial mortgage loans held for sale for which the fair value option has been elected are included in capital markets fee income and other. Regions also transfers certain commercial, investor real estate, and residential real estate mortgage portfolio loans to held for sale when management has the intent to sell in the near term. These held for sale loans are recorded at the lower of cost or estimated fair value. At the time of transfer, write-downs on the loans are recorded as charge-offs and a new cost basis is established. Any subsequent lower of cost or market adjustment is determined on an individual loan basis and is recognized in other non-interest expense. Gains and losses on the sale of non-performing commercial and investor real estate loans are included in other non-interest expense when realized as such amounts are viewed as credit costs. Gains and losses on sales of performing loans are included in non-interest income. See the “Fair Value Measurements” section below for discussion of determining estimated fair value. LOANS Loans that management has the intent and ability to hold for the foreseeable future or until maturity or payoff are considered loans held for investment (or portfolio loans). Loans held for investment are carried at the principal amount outstanding, net of premiums, discounts, unearned income and deferred loan fees and costs. Regions' loans balance is comprised of commercial, investor real estate and consumer loans. Interest income on all types of loans is accrued based on the contractual interest rate and the principal amount outstanding using methods that approximate the interest method, except for those loans classified as non-accrual. Premiums and discounts on purchased loans and non-refundable loan origination and commitment fees, net of direct costs of originating or acquiring loans, are deferred and recognized over the estimated lives of the related loans as an adjustment to the loans’ constant effective yield, which is included in interest income on loans. See Note 5 for further detail and information on loans. Regions engages in both direct and leveraged lease financing. The net investment in direct financing leases is the sum of all minimum lease payments and estimated residual values, less unearned income. Unearned income is recognized over the terms of the leases to produce a constant effective yield. The net investment in leveraged leases is the sum of all lease payments (less non-recourse debt payments) and estimated residual values, less unearned income. Income from leveraged leases is recognized over the term of the leases based on the unrecovered equity investment. Regions determines past due or delinquency status of a loan based on contractual payment terms. Commercial and investor real estate loans are placed on non-accrual if any of the following conditions occur: 1) collection in full of contractual principal and interest is no longer reasonably assured (even if current as to payment status), 2) a partial charge-off has occurred, unless the loan has been brought current under its contractual terms (original or restructured terms) and the full originally contracted principal and interest is considered to be fully collectible, or 3) the loan is delinquent on any principal or interest for 90 days or more unless the obligation is secured by collateral having a net realizable value (estimated fair value less costs to sell) sufficient to fully discharge the obligation and the loan is in the legal process of collection. Factors considered regarding full collection include assessment of changes in borrower’s cash flow, valuation of underlying collateral, ability and willingness of guarantors to provide credit support, and other conditions. Charge-offs on commercial and investor real estate loans are primarily based on the facts and circumstances of the individual loan and occur when available information confirms the loan is not or will not be fully collectible. Factors considered in making these determinations are the borrower’s and any guarantor’s ability and willingness to pay, the status of the account in bankruptcy court (if applicable), and collateral value. Commercial and investor real estate loan relationships of $250,000 or less are subject to charge-off or charge down to net realizable value at 180 days past due, based on collateral value. Non-accrual and charge-off decisions for consumer loans are dictated by the FFIEC's Uniform Retail Credit Classification and Account Management Policy which establishes standards for the classification and treatment of consumer loans. The charge-off process drives consumer non-accrual status as follows. If a consumer loan secured by real estate in a first lien position (residential first mortgage or home equity) becomes 180 days past due, Regions evaluates the loan for non-accrual status and potential charge-off based on net loan to value exposure. For home equity loans in a second lien position, the evaluation is performed at 120 days past due. If a loan is secured by collateral having a net realizable value sufficient to fully discharge the obligation, then a partial write-down is not necessary and the loan remains on accrual status, provided it is in the process of legal collection. If a partial charge-off is necessary as a result of the evaluation, then the remaining balance is placed on non-accrual. Consumer loans not secured by real estate are generally charged-off in full at either 120 days past due for closed-end loans, 180 days past due for open-end loans other than credit cards or the end of the month in which the loan becomes 180 days past due for credit cards. When loans are placed on non-accrual status, the accrual of interest, amortization of loan premium, accretion of loan discount and amortization/accretion of deferred net loan fees/costs are discontinued. When a commercial or investor real estate loan is placed on non-accrual status, uncollected interest accrued in the current year is reversed and charged to interest income. Uncollected interest accrued from prior years on commercial and investor real estate loans placed on non-accrual status in the current year is charged against the allowance for loan losses. When a consumer loan is placed on non-accrual status, all uncollected interest accrued is reversed and charged to interest income due to immateriality. Interest collections on commercial and investor real estate non-accrual loans are applied as principal reductions. Interest collections on consumer loans are recorded using the cash basis, due to immateriality. All loans on non-accrual status may be returned to accrual status and interest accrual resumed if all of the following conditions are met: 1) the loan is brought contractually current as to both principal and interest, 2) future payments are reasonably expected to continue being received in accordance with the terms of the loan and repayment ability can be reasonably demonstrated, and 3) the loan has been performing for at least six months. ALLOWANCE FOR CREDIT LOSSES Regions' allowance for credit losses (“allowance”) consists of two components: the allowance for loan losses, which is recorded as a contra-asset to loans, and the reserve for unfunded credit commitments, which is recorded in other liabilities. The allowance is reduced by actual losses (charge-offs) and increased by recoveries, if any. Regions charges losses against the allowance in the period the loss is confirmed. All adjustments to the allowance for loan losses are charged directly to expense through the provision for loan losses. All adjustments to the reserve for unfunded credit commitments are recorded in other non-interest expense. The allowance is maintained at a level believed appropriate by management to absorb probable credit losses inherent in the loan and unfunded credit commitment portfolios in accordance with GAAP and regulatory guidelines. Management’s determination of the appropriateness of the allowance is a quarterly process and is based on an evaluation and rating of the loan portfolio segments, historical loan loss experience, current economic conditions, collateral values securing loans, levels of problem loans, volume, growth, quality and composition of the loan portfolio, regulatory guidance, and other relevant factors. Changes in any of these, or other factors, or the availability of new information, could require that the allowance be adjusted in future periods. Actual losses could vary from management’s estimates. Management attributes portions of the allowance to loans that it evaluates and determines to be impaired and to groups of loans that it evaluates collectively. However, the entire allowance is available to cover all charge-offs that arise from the loan portfolio. CALCULATION OF ALLOWANCE FOR CREDIT LOSSES Commercial and Investor Real Estate Components Impaired Loans Loans deemed to be impaired include non-accrual loans, excluding consumer loans, and all TDRs. Regions considers the current value of collateral, credit quality of any guarantees, guarantor’s liquidity and willingness to repay, the loan structure, and other factors when evaluating whether an individual loan is impaired. Other factors may include the industry and geographic region of the borrower, size and financial condition of the borrower, cash flow and leverage of the borrower and Regions’ evaluation of the borrower’s management. For non-accrual commercial and investor real estate loans (including TDRs) equal to or greater than $2.5 million , the allowance for loan losses is based on a note-level evaluation considering the facts and circumstances specific to each borrower. For these loans, Regions measures the level of impairment based on the present value of the estimated cash flows, the estimated value of the collateral or, if available, the observable market price. Regions generally uses the estimated cash flow method to measure impairment. For commercial and investor real estate accruing TDRs and all non-accruing loans less than $2.5 million , the allowance for loan losses is based on a discounted cash flow analysis performed at the note level, where estimated projected cash flows reflect credit losses based on statistical information (including historical default information) derived from loans with similar risk characteristics (e.g., credit quality indicator and product type) using PDs and LGDs as described in the following paragraph. Non-Impaired Loans For all other commercial and investor real estate loans, the allowance for loan losses is calculated at a pool level based on credit quality indicators and product type. Statistically determined PDs and LGDs are calculated based on historical default and loss information for similar loans. The historical default and loss information is measured over a relevant period for each loan pool. The pool level allowance is calculated using the PD and LGD estimates and is adjusted as appropriate based on additional analysis of long-term average loss experience compared to previously forecasted losses, external loss data and other risks identified from current economic conditions and credit quality trends. Various one year PD measurements are used in conjunction with life-of-loan LGD measurements to estimate incurred losses. As a result, losses are effectively covered over a two to three year period for loans that are currently in default and those estimated to default within the next twelve months. Consumer Components For consumer loans, the classes are segmented into pools of loans with similar risk characteristics. For most consumer loan pools, historical losses are the primary factor in establishing the allowance allocated to each pool. The twelve month loss rate is the basis for the allocation and it may be adjusted based on deteriorating trends, portfolio growth, or other factors determined by management to be relevant. The allowance for loan losses for the residential first mortgage non-TDR pool is calculated based on a twelve-month historical loss rate segmented based on the following risk characteristics: past due and accrual status and further by geography, property use and amortization type for accruing, non-past due loans. The allowance for loan losses for residential first mortgage TDRs is calculated based on a discounted cash flow analysis on pools of homogeneous loans. Cash flows are projected using the restructured terms and then discounted at the original note rate. The projected cash flows assume a default rate, which is based on historical performance of residential first mortgage TDRs. The allowance for loan losses for the home equity pool is calculated based on a twelve-month historical loss rate segmented based on the following risk characteristics: lien position, TDR status, geography, non-accrual and past due status, and refreshed FICO scores for accruing, non-past due loans. Qualitative Factors While quantitative allowance methodologies strive to reflect all risk factors, any estimate involves assumptions and uncertainties resulting in some level of imprecision. Imprecision exists in the estimation process due to the inherent time lag of obtaining information and variations between estimates and actual outcomes. Regions adjusts the allowance in consideration of quantitative and qualitative factors which may not be directly measured in the note-level or pooled calculations, including, but not limited to: • Credit quality trends, • Loss experience in particular portfolios, • Macroeconomic factors such as unemployment, real estate prices, or commodity pricing volatility, • Changes in risk selection and underwriting standards, • Shifts in credit quality of consumer customers which is not yet reflected in the historical data. Reserve for Unfunded Credit Commitments In order to estimate a reserve for unfunded commitments, Regions uses a process consistent with that used in developing the allowance for loan losses. The reserve is based on an EAD multiplied by a PD multiplied by an LGD. The EAD is estimated based on an analysis of historical funding patterns for defaulted loans in various categories. The PD and LGD align with the statistically-calculated parameters used to calculate the allowance for loan losses for various pools, which are based on credit quality indicators and product type. The methodology applies to commercial and investor real estate credit commitments and standby letters of credit that are not unconditionally cancellable. Refer to Note 6 for further discussion regarding the calculation of the allowance for credit losses. TDRs TDRs are loans in which the borrower is experiencing financial difficulty at the time of restructuring, and Regions has granted a concession to the borrower. TDRs are undertaken in order to improve the likelihood of recovery on the loan and may take the form of modifications made with the stated interest rate lower than the current market rate for new debt with similar risk, other modifications to the structure of the loan that fall outside of normal underwriting policies and procedures, or in limited circumstances forgiveness of principal and/or interest. TDRs can involve loans remaining on non-accrual, moving to non-accrual, or continuing on accrual status, depending on the individual facts and circumstances of the borrower. TDRs are subject to policies governing accrual/non-accrual evaluation consistent with all other loans of the same product type as discussed in the “Loans” section above. All loans with the TDR designation are considered to be impaired, even if they are accruing. See the “Calculation of Allowance For Credit Losses” section above for Regions’ allowance for loan losses methodology related to TDRs. The CAP was designed to evaluate potential consumer loan participants as early as possible in the life cycle of the troubled loan (as described in Note 6). Many of the modifications are finalized without the borrower ever reaching the applicable number of days past due, and therefore the loan may never be placed on non-accrual. Accordingly, given the positive impact of the restructuring on the likelihood of recovery of cash flows due under the modified terms, accrual status continues to be appropriate for these loans. OTHER EARNING ASSETS Other earning assets consist primarily of investments in FRB stock, FHLB stock, and operating lease assets. See Note 8 for additional information. INVESTMENTS IN FEDERAL RESERVE BANK AND FEDERAL HOME LOAN BANK STOCK Ownership of FRB and FHLB stock is a requirement for all banks seeking membership into and access to the services provided by these banking systems. These shares are accounted for at amortized cost, which approximates fair value. INVESTMENTS IN OPERATING LEASES Investments in operating leases represent the assets underlying the related lease contracts and are reported at cost, less accumulated depreciation and net of origination fees and costs. Depreciation on these assets is generally provided on a straight-line basis over the lease term down to an estimated residual value. Regions periodically evaluates its depreciation rate for leased assets based on projected residual values and adjusts depreciation expense over the remaining life of the lease if deemed appropriate. Regions also evaluates the current value of the operating lease assets and tests for impairment when indicators of impairment are present. Income from operating lease assets includes lease origination fees, net of lease origination costs, and is recognized as operating lease revenue on a straight line basis over the scheduled lease term. The accrual of revenue on operating leases is generally discontinued at the time an account is determined to be uncollectible. Operating lease revenue and the depreciation expense on the related operating lease assets are included as components of net interest income and other financing income on the consolidated statements of income. When a leased asset is returned, its remaining value is reclassified from other earning assets to other assets and recorded at the lower of cost or estimated fair value, less costs to sell, on Regions' consolidated balance sheet. Impairment of the operating lease asset, as well as residual value gains and losses at the end of the lease term are recorded through other non-interest income. PREMISES AND EQUIPMENT Premises and equipment are stated at cost, less accumulated depreciation and amortization, as applicable. Land is carried at cost. Depreciation expense is computed using the straight-line method over the estimated useful lives of the assets. Leasehold improvements are amortized using the straight-line method over the estimated useful lives of the improvements (or the terms of the leases, if shorter). Generally, premises and leasehold improvements are depreciated or amortized over 7 - 40 years. Furniture and equipment are generally depreciated or amortized over 3 - 10 years. Premises and equipment are evaluated for impairment at least annually, or more often if events or circumstances indicate that the carrying value of the asset may not be recoverable. Maintenance and repairs are charged to non-interest expense in the consolidated statements of income. Improvements that extend the useful life of the asset are capitalized to the carrying value and depreciated. See Note 9 for detail of premises and equipment. Regions enters into lease transactions for the right to use assets. These leases vary in term and, from time to time, include incentives and/or rent escalations. Examples of incentives include periods of “free” rent and leasehold improvement incentives. Regions recognizes incentives and escalations on a straight-line basis over the lease term as a reduction of or increase to rent expense, as applicable, within net occupancy expense in the consolidated statements of income. INTANGIBLE ASSETS Intangible assets include goodwill, which is the excess of cost over the fair value of net assets of acquired businesses, and other identifiable intangible assets. Other identifiable intangible assets primarily include the following: 1) core deposit intangible assets, which are amounts recorded related to the value of acquired indeterminate maturity deposits, 2) amounts capitalized related to the value of acquired customer relationships, 3) amounts recorded related to employment agreements with certain individuals of acquired entities, and 4) the Fannie Mae DUS license. Core deposit intangibles and certain other identifiable intangibles are amortized on an accelerated basis over their expected useful lives. The Company’s goodwill is tested for impairment on an annual basis in the fourth quarter, or more often if events or circumstances indicate that there may be impairment. Regions assesses the following indicators of goodwill impairment for each reporting period: • Recent operating performance, • Changes in market capitalization, • Regulatory actions and assessments, • Changes in the business climate (including legislation, legal factors and competition), • Company-specific factors (including changes in key personnel, asset impairments, and business dispositions), and • Trends in the banking industry. Adverse changes in the economic environment, declining operations, or other factors could result in a decline in the implied estimated fair value of goodwill. A goodwill impairment test includes two steps. Step One, used to identify potential impairment, compares the estimated fair value of a reporting unit with its carrying amount, including goodwill. If the estimated fair value of a reporting unit exceeds its carrying amount, goodwill of the reporting unit is considered not impaired. If the carrying amount of a reporting unit exceeds its estimated fair value, the second step of the goodwill impairment test is performed to measure the amount of impairment loss, if any. Step Two of the goodwill impairment test compares the implied estimated fair value of reporting unit goodwill with the carrying amount of that goodwill. If the carrying amount of goodwill for that reporting unit exceeds the implied estimated fair value of that unit’s goodwill, an impairment loss is recognized in other non-interest expense in an amount equal to that excess. For purposes of performing Step One of the goodwill impairment test, Regions uses both income and market approaches to value its reporting units. The income approach, which is the primary valuation approach, consists of discounting projected long-term future cash flows, which are derived from internal forecasts and economic expectations for the respective reporting units. The significant inputs

Variable Interest Entities

Variable Interest Entities	12 Months Ended
	Dec. 31, 2017
Disclosure Variable Interest Entities Schedule Of Equity Method Investments [Abstract]
Variable Interest Entities	VARIABLE INTEREST ENTITIES Regions is involved in various entities that are considered to be VIEs, as defined by authoritative accounting literature. Generally, a VIE is a corporation, partnership, trust or other legal structure that either does not have equity investors with substantive voting rights or has equity investors that do not provide sufficient financial resources for the entity to support its activities. The following discusses the VIEs in which Regions has a significant interest. Regions periodically invests in various limited partnerships that sponsor affordable housing projects, which are funded through a combination of debt and equity. These partnerships meet the definition of a VIE. Regions uses the proportional amortization method for these investments. Due to the nature of the management activities of the general partner, Regions is not the primary beneficiary of these partnerships and accounts for these investments in other assets on the consolidated balance sheets. See Note 1 for additional details. Regions reports its commitments to make future investments in other liabilities on the consolidated balance sheets. The Company receives tax credits and other tax benefits, which are reported as a reduction of income tax expense (or increase to income tax benefit) related to these transactions. Additionally, Regions has short-term construction loans or letters of credit commitments with certain limited partnerships. The funded portion of the short-term loans and letters of credit is classified as commercial and industrial loans or investor real estate construction loans, as applicable, in Note 5. Regions also has long-term mortgage loans with certain limited partnerships. These long-term loans are classified as investor real estate mortgage loans in Note 5. The Company recognized $160 million , including $23 million due to Tax Reform, and $117 million in amortization expense, as well as $144 million and $130 million of tax credits related to investments in qualified affordable housing projects utilizing the proportional amortization method during 2017 and 2016, respectively. The Company also recognized $45 million and $37 million of other tax benefits related to these investments during 2017 and 2016, respectively. A summary of Regions’ proportional amortization method investments, equity method investments and related loans and letters of credit, representing Regions’ maximum exposure to loss as of December 31 is as follows: 2017 2016 (In millions) Proportional amortization method investments included in other assets $ 1,144 $ 1,013 Equity method investments included in other assets 20 21 Unfunded commitments included in other liabilities 348 301 Short-term construction loans and letters of credit commitments 317 249 Funded portion of short-term loans and letters of credit 129 103 In addition to the investments discussed above, Regions also syndicates affordable housing investments. In these syndication transactions, Regions creates affordable housing funds in which a subsidiary is the general partner or managing member and sells limited partnership interests to third parties. Regions' general partner or managing member interest represents an insignificant interest in the affordable housing fund. Regions generates revenue from the syndication of these funds and also asset management revenue by managing the funds. The affordable housing funds meet the definition of a VIE. The primary benefits are the rights to receive tax credits and other tax benefits, which are transferred to the third party investors. As Regions is not the primary beneficiary and does not have a significant interest, these investments are not consolidated. At December 31, 2017, the value of Regions’ general partnership interest in affordable housing investments was immaterial. Affordable housing investments that the Company intends to syndicate but have not yet syndicated as of December 31, 2017 are not VIEs and are accounted for within other assets at the lower of cost or fair value totaling approximately $2 million .

Discontinued Operations

Discontinued Operations	12 Months Ended
	Dec. 31, 2017
Discontinued Operations and Disposal Groups [Abstract]
Discontinued Operations	DISCONTINUED OPERATIONS On January 11, 2012, Regions entered into a stock purchase agreement to sell Morgan Keegan and related affiliates to Raymond James. The transaction closed on April 2, 2012. Regions Investment Management, Inc. (formerly known as Morgan Asset Management, Inc.) and Regions Trust were not included in the sale. In connection with the closing of the sale, Regions agreed to indemnify Raymond James for all litigation matters related to pre-closing activities. See Note 24 for related disclosure. The following table represents the condensed results of operations for discontinued operations: Year Ended December 31 2017 2016 2015 (In millions, except per share data) Non-interest expense: Professional and legal expenses/(recoveries) $ (10 ) $ (9 ) $ 21 Other 2 1 1 Total non-interest expense (8 ) (8 ) 22 Income (loss) from discontinued operations before income taxes 8 8 (22 ) Income tax expense (benefit) 2 3 (9 ) Income (loss) from discontinued operations, net of tax $ 6 $ 5 $ (13 ) Earnings (loss) per common share from discontinued operations: Basic $ 0.01 $ 0.00 $ (0.01 ) Diluted $ 0.00 $ 0.00 $ (0.01 )

Securities

Securities	12 Months Ended
	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Securities	SECURITIES The amortized cost, gross unrealized gains and losses, and estimated fair value of securities held to maturity and securities available for sale are as follows: December 31, 2017 Recognized in OCI (1) Not recognized in OCI Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Carrying Value Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (In millions) Securities held to maturity: Mortgage-backed securities: Residential agency $ 1,051 $ — $ (40 ) $ 1,011 $ 12 $ (4 ) $ 1,019 Commercial agency 651 — (4 ) 647 5 (4 ) 648 $ 1,702 $ — $ (44 ) $ 1,658 $ 17 $ (8 ) $ 1,667 Securities available for sale: U.S. Treasury securities $ 333 $ — $ (2 ) $ 331 $ 331 Federal agency securities 28 — — 28 28 Mortgage-backed securities: Residential agency 17,622 53 (244 ) 17,431 17,431 Residential non-agency 3 — — 3 3 Commercial agency 3,739 5 (30 ) 3,714 3,714 Commercial non-agency 787 4 (3 ) 788 788 Corporate and other debt securities 1,093 20 (5 ) 1,108 1,108 Equity securities 225 — — 225 225 $ 23,830 $ 82 $ (284 ) $ 23,628 $ 23,628 December 31, 2016 Recognized in OCI (1) Not recognized in OCI Amortized Gross Unrealized Gains Gross Unrealized Losses Carrying Value Gross Gross Estimated (In millions) Securities held to maturity: Mortgage-backed securities: Residential agency $ 1,249 $ — $ (49 ) $ 1,200 $ 12 $ (3 ) $ 1,209 Commercial agency 167 — (5 ) 162 — (2 ) 160 $ 1,416 $ — $ (54 ) $ 1,362 $ 12 $ (5 ) $ 1,369 Securities available for sale: U.S. Treasury securities $ 303 $ 1 $ (1 ) $ 303 $ 303 Federal agency securities 35 — — 35 35 Obligations of states and political subdivisions 1 — — 1 1 Mortgage-backed securities: Residential agency 17,531 95 (255 ) 17,371 17,371 Residential non-agency 4 — — 4 4 Commercial agency 3,486 9 (32 ) 3,463 3,463 Commercial non-agency 1,124 8 (3 ) 1,129 1,129 Corporate and other debt securities 1,272 19 (17 ) 1,274 1,274 Equity securities 194 7 — 201 201 $ 23,950 $ 139 $ (308 ) $ 23,781 $ 23,781 _________ (1) The gross unrealized losses recognized in OCI on held to maturity securities resulted from a transfer of available for sale securities to held to maturity in the second quarter of 2013. Securities with carrying values of $8.1 billion and $11.6 billion at December 31, 2017 and 2016 , respectively, were pledged to secure public funds trading positions, trust deposits and certain borrowing arrangements. Included within total pledged securities is approximately $50 million of encumbered U.S. Treasury securities at both December 31, 2017 and 2016. The amortized cost and estimated fair value of securities held to maturity and securities available for sale at December 31, 2017 , by contractual maturity, are shown below. 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. Amortized Cost Estimated Fair Value (In millions) Securities held to maturity: Mortgage-backed securities: Residential agency $ 1,051 $ 1,019 Commercial agency 651 648 $ 1,702 $ 1,667 Securities available for sale: Due in one year or less $ 33 $ 33 Due after one year through five years 876 878 Due after five years through ten years 462 471 Due after ten years 83 85 Mortgage-backed securities: Residential agency 17,622 17,431 Residential non-agency 3 3 Commercial agency 3,739 3,714 Commercial non-agency 787 788 Equity securities 225 225 $ 23,830 $ 23,628 The following tables present gross unrealized losses and the related estimated fair value of securities held to maturity and securities available for sale at December 31, 2017 and 2016 . For securities transferred to held to maturity from available for sale, the analysis in the tables below is comparing the securities' original amortized cost to its current estimated fair value. These securities are segregated between investments that have been in a continuous unrealized loss position for less than twelve months and for twelve months or more. December 31, 2017 Less Than Twelve Months Twelve Months or More Total Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses (In millions) Securities held to maturity: Mortgage-backed securities: Residential agency $ — $ — $ 1,019 $ (32 ) $ 1,019 $ (32 ) Commercial agency — — 150 (7 ) 150 (7 ) $ — $ — $ 1,169 $ (39 ) $ 1,169 $ (39 ) Securities available for sale: U.S. Treasury securities $ 221 $ (1 ) $ 84 $ (1 ) $ 305 $ (2 ) Mortgage-backed securities: Residential agency 5,157 (40 ) 8,195 (204 ) 13,352 (244 ) Commercial agency 1,666 (10 ) 904 (20 ) 2,570 (30 ) Commercial non-agency 393 (2 ) 61 (1 ) 454 (3 ) All other securities 330 (2 ) 105 (3 ) 435 (5 ) $ 7,767 $ (55 ) $ 9,349 $ (229 ) $ 17,116 $ (284 ) December 31, 2016 Less Than Twelve Months Twelve Months or More Total Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses (In millions) Securities held to maturity: Mortgage-backed securities: Residential agency $ 850 $ (26 ) $ 359 $ (14 ) $ 1,209 $ (40 ) Commercial agency — — 160 (7 ) 160 (7 ) $ 850 $ (26 ) $ 519 $ (21 ) $ 1,369 $ (47 ) Securities available for sale: U.S. Treasury securities $ 112 $ (1 ) $ 18 $ — $ 130 $ (1 ) Mortgage-backed securities: Residential agency 12,071 (245 ) 570 (10 ) 12,641 (255 ) Commercial agency 2,199 (31 ) 45 (1 ) 2,244 (32 ) Commercial non-agency 402 (2 ) 176 (1 ) 578 (3 ) All other securities 382 (6 ) 218 (11 ) 600 (17 ) $ 15,166 $ (285 ) $ 1,027 $ (23 ) $ 16,193 $ (308 ) The number of individual securities in an unrealized loss position in the tables above increased from 1,613 at December 31, 2016 to 1,762 at December 31, 2017 . The increase in the number of securities and the total amount of unrealized losses was primarily due to changes in market interest rates. In instances where an unrealized loss existed, there was no indication of an adverse change in credit on the underlying positions in the tables above. As it relates to these positions, management believes no individual unrealized loss, other than those discussed below, represented an OTTI as of those dates. The Company does not intend to sell, and it is not more likely than not that the Company will be required to sell, the positions before the recovery of their amortized cost basis, which may be at maturity. As part of the Company's normal process for evaluating OTTI, management did identify a limited number of positions where an OTTI was believed to exist during 2017 . For the year ended 2017 , such impairments were immaterial. Gross realized gains and gross realized losses on sales of securities available for sale, as well as OTTI losses, for years ended December 31 are shown in the table below. The cost of securities sold is based on the specific identification method. 2017 2016 2015 (In millions) Gross realized gains $ 25 $ 36 $ 44 Gross realized losses (5 ) (28 ) (8 ) OTTI (1 ) (2 ) (7 ) Securities available for sale gains, net (1) $ 19 $ 6 $ 29 _________ (1) The securities gains (losses), net balances above exclude net trading securities gains of $3 million recognized during 2017.

Loans

Loans	12 Months Ended
	Dec. 31, 2017
Receivables [Abstract]
Loans	LOANS The following table presents the distribution of Regions' loan portfolio by segment and class, net of unearned income as of December 31 : 2017 2016 (In millions) Commercial and industrial $ 36,115 $ 35,012 Commercial real estate mortgage—owner-occupied 6,193 6,867 Commercial real estate construction—owner-occupied 332 334 Total commercial 42,640 42,213 Commercial investor real estate mortgage 4,062 4,087 Commercial investor real estate construction 1,772 2,387 Total investor real estate 5,834 6,474 Residential first mortgage 14,061 13,440 Home equity 10,164 10,687 Indirect—vehicles 3,326 4,040 Indirect—other consumer 1,467 920 Consumer credit card 1,290 1,196 Other consumer 1,165 1,125 Total consumer 31,473 31,408 Total loans, net of unearned income (1) $ 79,947 $ 80,095 _________ (1) Loans are presented net of unearned income, unamortized discounts and premiums and net deferred loan costs of $43 million and $141 million at December 31, 2017 and 2016 , respectively. During 2017 , Regions purchased approximately $238 million in indirect-other consumer loans from third parties. During 2016 , Regions purchased approximately $985 million in indirect-vehicles and indirect-other consumer loans from third parties. The following tables include details regarding Regions’ investment in leveraged leases included within the commercial and industrial loan portfolio class as of and for the years ended December 31 : 2017 2016 (In millions) Rentals receivable $ 248 $ 303 Estimated residuals on leveraged leases 196 203 Unearned income on leveraged leases 160 184 2017 2016 2015 (In millions) Pre-tax income from leveraged leases $ 22 $ 28 $ 34 Income tax expense on income from leveraged leases 24 31 33 The income above does not include leveraged lease termination gains of $1 million , $8 million and $8 million with related income tax expense of $1 million , $11 million and less than $1 million for the years ended December 31, 2017 , 2016 and 2015 , respectively. Pre-tax income from leveraged leases was reduced by $6 million during 2017 as a result of Tax Reform. At December 31, 2017 , $22.0 billion in securities and net eligible loans held by Regions were pledged to secure current and potential borrowings from the FHLB. At December 31, 2017 , an additional $21.9 billion in net eligible loans held by Regions were pledged to the FRB for potential borrowings.

Allowance for Credit Losses

Allowance for Credit Losses	12 Months Ended
	Dec. 31, 2017
Receivables [Abstract]
Allowance for Credit Losses	ALLOWANCE FOR CREDIT LOSSES Regions determines the appropriate level of the allowance on a quarterly basis. The methodology is described in Note 1. ROLLFORWARD OF ALLOWANCE FOR CREDIT LOSSES The following tables present analyses of the allowance for credit losses by portfolio segment for the years ended December 31, 2017 , 2016 and 2015 . The total allowance for loan losses and the related loan portfolio ending balances are then disaggregated to detail the amounts derived through individual evaluation and collective evaluation for impairment. The allowance for loan losses related to individually evaluated loans is attributable to reserves for non-accrual commercial and investor real estate loans and all TDRs. The allowance for loan losses and the loan portfolio ending balances related to collectively evaluated loans is attributable to the remainder of the portfolio. 2017 Commercial Investor Real Estate Consumer Total (In millions) Allowance for loan losses, January 1, 2017 $ 753 $ 85 $ 253 $ 1,091 Provision (credit) for loan losses (28 ) (42 ) 220 150 Loan losses: Charge-offs (176 ) (2 ) (256 ) (434 ) Recoveries 42 23 62 127 Net loan losses (134 ) 21 (194 ) (307 ) Allowance for loan losses, December 31, 2017 591 64 279 934 Reserve for unfunded credit commitments, January 1, 2017 64 5 — 69 Provision (credit) for unfunded credit losses (15 ) (1 ) — (16 ) Reserve for unfunded credit commitments, December 31, 2017 49 4 — 53 Allowance for credit losses, December 31, 2017 $ 640 $ 68 $ 279 $ 987 Portion of ending allowance for loan losses: Individually evaluated for impairment $ 171 $ 8 $ 47 $ 226 Collectively evaluated for impairment 420 56 232 708 Total allowance for loan losses $ 591 $ 64 $ 279 $ 934 Portion of loan portfolio ending balance: Individually evaluated for impairment $ 756 $ 96 $ 706 $ 1,558 Collectively evaluated for impairment 41,884 5,738 30,767 78,389 Total loans evaluated for impairment $ 42,640 $ 5,834 $ 31,473 $ 79,947 2016 Commercial Investor Real Estate Consumer Total (In millions) Allowance for loan losses, January 1, 2016 $ 758 $ 97 $ 251 $ 1,106 Provision (credit) for loan losses 95 (23 ) 190 262 Loan losses: Charge-offs (143 ) (2 ) (253 ) (398 ) Recoveries 43 13 65 121 Net loan losses (100 ) 11 (188 ) (277 ) Allowance for loan losses, December 31, 2016 753 85 253 1,091 Reserve for unfunded credit commitments, January 1, 2016 47 5 — 52 Provision (credit) for unfunded credit losses 17 — — 17 Reserve for unfunded credit commitments, December 31, 2016 64 5 — 69 Allowance for credit losses, December 31, 2016 $ 817 $ 90 $ 253 $ 1,160 Portion of ending allowance for loan losses: Individually evaluated for impairment $ 231 $ 13 $ 60 $ 304 Collectively evaluated for impairment 522 72 193 787 Total allowance for loan losses $ 753 $ 85 $ 253 $ 1,091 Portion of loan portfolio ending balance: Individually evaluated for impairment $ 1,069 $ 107 $ 770 $ 1,946 Collectively evaluated for impairment 41,144 6,367 30,638 78,149 Total loans evaluated for impairment $ 42,213 $ 6,474 $ 31,408 $ 80,095 2015 Commercial Investor Real Estate Consumer Total (In millions) Allowance for loan losses, January 1, 2015 $ 654 $ 150 $ 299 $ 1,103 Provision (credit) for loan losses 191 (65 ) 115 241 Loan losses: Charge-offs (154 ) (15 ) (234 ) (403 ) Recoveries 67 27 71 165 Net loan losses (87 ) 12 (163 ) (238 ) Allowance for loan losses, December 31, 2015 758 97 251 1,106 Reserve for unfunded credit commitments, January 1, 2015 57 8 — 65 Provision (credit) for unfunded credit losses (10 ) (3 ) — (13 ) Reserve for unfunded credit commitments, December 31, 2015 47 5 — 52 Allowance for credit losses, December 31, 2015 $ 805 $ 102 $ 251 $ 1,158 Portion of ending allowance for loan losses: Individually evaluated for impairment $ 189 $ 26 $ 68 $ 283 Collectively evaluated for impairment 569 71 183 823 Total allowance for loan losses $ 758 $ 97 $ 251 $ 1,106 Portion of loan portfolio ending balance: Individually evaluated for impairment $ 743 $ 191 $ 835 $ 1,769 Collectively evaluated for impairment 43,039 6,756 29,598 79,393 Total loans evaluated for impairment $ 43,782 $ 6,947 $ 30,433 $ 81,162 PORTFOLIO SEGMENT RISK FACTORS The following describe the risk characteristics relevant to each of the portfolio segments. Commercial —The commercial loan portfolio segment includes commercial and industrial loans to commercial customers for use in normal business operations to finance working capital needs, equipment purchases or other expansion projects. Commercial also includes owner-occupied commercial real estate mortgage loans to operating businesses, which are loans for long-term financing of land and buildings, and are repaid by cash flow generated by business operations. Owner-occupied construction loans are made to commercial businesses for the development of land or construction of a building where the repayment is derived from revenues generated from the business of the borrower. Collection risk in this portfolio is driven by the creditworthiness of underlying borrowers, particularly cash flow from customers’ business operations, and the sensitivity to market fluctuations in commodity prices. Investor Real Estate —Loans for real estate development are repaid through cash flows related to the operation, sale or refinance of the property. This portfolio segment includes extensions of credit to real estate developers or investors where repayment is dependent on the sale of real estate or income generated from the real estate collateral. A portion of Regions’ investor real estate portfolio segment consists of loans secured by residential product types (land, single-family and condominium loans) within Regions’ markets. Additionally, these loans are made to finance income-producing properties such as apartment buildings, office and industrial buildings, and retail shopping centers. Loans in this portfolio segment are particularly sensitive to the valuation of real estate. Consumer —The consumer loan portfolio segment includes residential first mortgage, home equity, indirect-vehicles, indirect-other consumer, consumer credit card, and other consumer loans. Residential first mortgage loans represent loans to consumers to finance a residence. These loans are typically financed over a 15 to 30 year term and, in most cases, are extended to borrowers to finance their primary residence. Home equity lending includes both home equity loans and lines of credit. This type of lending, which is secured by a first or second mortgage on the borrower’s residence, allows customers to borrow against the equity in their home. Real estate market values as of the time the loan or line is secured directly affect the amount of credit extended and, in addition, changes in these values impact the depth of potential losses. Indirect-vehicles lending, which is lending initiated through third-party business partners, largely consists of loans made through automotive dealerships. Indirect-other consumer lending represents other point of sale lending through third parties. Consumer credit card includes Regions branded consumer credit card accounts. Other consumer loans include other revolving consumer accounts, direct consumer loans, and overdrafts. Loans in this portfolio segment are sensitive to unemployment and other key consumer economic measures. CREDIT QUALITY INDICATORS Commercial and investor real estate loan portfolio segments are detailed by categories related to underlying credit quality and probability of default. Regions assigns these categories at loan origination and reviews the relationship utilizing a risk-based approach on, at minimum, an annual basis or at any time management becomes aware of information affecting the borrowers' ability to fulfill their obligations. Both quantitative and qualitative factors are considered in this review process. These categories are utilized to develop the associated allowance. • Pass—includes obligations where the probability of default is considered low; • Special Mention—includes obligations that have potential weakness that may, if not reversed or corrected, weaken the credit or inadequately protect the Company’s position at some future date. Obligations in this category may also be subject to economic or market conditions that may, in the future, have an adverse effect on debt service ability; • Substandard Accrual—includes obligations that exhibit a well-defined weakness that presently jeopardizes debt repayment, even though they are currently performing. These obligations are characterized by the distinct possibility that the Company may incur a loss in the future if these weaknesses are not corrected; • Non-accrual—includes obligations where management has determined that full payment of principal and interest is in doubt. Substandard accrual and non-accrual loans are often collectively referred to as “classified.” Special mention, substandard accrual, and non-accrual loans are often collectively referred to as “criticized and classified.” Classes in the consumer portfolio segment are disaggregated by accrual status. The following tables present credit quality indicators for the loan portfolio segments and classes, excluding loans held for sale, as of December 31, 2017 and 2016 . 2017 Pass Special Mention Substandard Accrual Non-accrual Total (In millions) Commercial and industrial $ 34,420 $ 686 $ 605 $ 404 $ 36,115 Commercial real estate mortgage—owner-occupied 5,674 236 165 118 6,193 Commercial real estate construction—owner-occupied 313 3 10 6 332 Total commercial $ 40,407 $ 925 $ 780 $ 528 $ 42,640 Commercial investor real estate mortgage $ 3,905 $ 63 $ 89 $ 5 $ 4,062 Commercial investor real estate construction 1,706 19 46 1 1,772 Total investor real estate $ 5,611 $ 82 $ 135 $ 6 $ 5,834 Accrual Non-accrual Total (In millions) Residential first mortgage $ 14,014 $ 47 $ 14,061 Home equity 10,095 69 10,164 Indirect—vehicles 3,326 — 3,326 Indirect—other consumer 1,467 — 1,467 Consumer credit card 1,290 — 1,290 Other consumer 1,165 — 1,165 Total consumer $ 31,357 $ 116 $ 31,473 $ 79,947 2016 Pass Special Mention Substandard Accrual Non-accrual Total (In millions) Commercial and industrial $ 32,619 $ 658 $ 1,112 $ 623 $ 35,012 Commercial real estate mortgage—owner-occupied 6,190 221 246 210 6,867 Commercial real estate construction—owner-occupied 308 8 15 3 334 Total commercial $ 39,117 $ 887 $ 1,373 $ 836 $ 42,213 Commercial investor real estate mortgage $ 3,766 $ 190 $ 114 $ 17 $ 4,087 Commercial investor real estate construction 2,192 129 66 — 2,387 Total investor real estate $ 5,958 $ 319 $ 180 $ 17 $ 6,474 Accrual Non-accrual Total (In millions) Residential first mortgage $ 13,390 $ 50 $ 13,440 Home equity 10,595 92 10,687 Indirect—vehicles 4,040 — 4,040 Indirect—other consumer 920 — 920 Consumer credit card 1,196 — 1,196 Other consumer 1,125 — 1,125 Total consumer $ 31,266 $ 142 $ 31,408 $ 80,095 AGING ANALYSIS The following tables include an aging analysis of DPD for each portfolio segment and class as of December 31, 2017 and 2016 : 2017 Accrual Loans 30-59 DPD 60-89 DPD 90+ DPD Total 30+ DPD Total Accrual Non-accrual Total (In millions) Commercial and industrial $ 28 $ 7 $ 4 $ 39 $ 35,711 $ 404 $ 36,115 Commercial real estate mortgage—owner-occupied 18 8 1 27 6,075 118 6,193 Commercial real estate construction—owner-occupied — — — — 326 6 332 Total commercial 46 15 5 66 42,112 528 42,640 Commercial investor real estate mortgage 1 1 1 3 4,057 5 4,062 Commercial investor real estate construction — — — — 1,771 1 1,772 Total investor real estate 1 1 1 3 5,828 6 5,834 Residential first mortgage 95 85 216 396 14,014 47 14,061 Home equity 53 27 37 117 10,095 69 10,164 Indirect—vehicles 48 13 9 70 3,326 — 3,326 Indirect—other consumer 9 5 — 14 1,467 — 1,467 Consumer credit card 11 7 19 37 1,290 — 1,290 Other consumer 13 4 4 21 1,165 — 1,165 Total consumer 229 141 285 655 31,357 116 31,473 $ 276 $ 157 $ 291 $ 724 $ 79,297 $ 650 $ 79,947 2016 Accrual Loans 30-59 DPD 60-89 DPD 90+ DPD Total 30+ DPD Total Accrual Non-accrual Total (In millions) Commercial and industrial $ 59 $ 11 $ 6 $ 76 $ 34,389 $ 623 $ 35,012 Commercial real estate mortgage—owner-occupied 29 7 2 38 6,657 210 6,867 Commercial real estate construction—owner-occupied 1 — — 1 331 3 334 Total commercial 89 18 8 115 41,377 836 42,213 Commercial investor real estate mortgage 6 8 — 14 4,070 17 4,087 Commercial investor real estate construction — — — — 2,387 — 2,387 Total investor real estate 6 8 — 14 6,457 17 6,474 Residential first mortgage 99 63 212 374 13,390 50 13,440 Home equity 60 22 33 115 10,595 92 10,687 Indirect—vehicles 56 14 10 80 4,040 — 4,040 Indirect—other consumer 5 3 — 8 920 — 920 Consumer credit card 9 7 15 31 1,196 — 1,196 Other consumer 13 5 5 23 1,125 — 1,125 Total consumer 242 114 275 631 31,266 142 31,408 $ 337 $ 140 $ 283 $ 760 $ 79,100 $ 995 $ 80,095 IMPAIRED LOANS The following tables present details related to the Company’s impaired loans as of December 31, 2017 and 2016 . Loans deemed to be impaired include all TDRs and all non-accrual commercial and investor real estate loans, excluding leases. Loans which have been fully charged-off do not appear in the tables below. Non-accrual Impaired Loans 2017 Book Value (3) Unpaid Principal Balance (1) Charge-offs and Payments Applied (2) Total Impaired Loans on Non-accrual Status Impaired Loans on Non-accrual Status with No Related Allowance Impaired Loans on Non-accrual Status with Related Allowance Related Allowance for Loan Losses Coverage % (4) (Dollars in millions) Commercial and industrial $ 480 $ 80 $ 400 $ 29 $ 371 $ 103 38.1 % Commercial real estate mortgage—owner-occupied 133 15 118 20 98 38 39.8 Commercial real estate construction—owner-occupied 7 1 6 — 6 3 57.1 Total commercial 620 96 524 49 475 144 38.7 Commercial investor real estate mortgage 6 1 5 — 5 2 50.0 Commercial investor real estate construction 1 — 1 — 1 — — Total investor real estate 7 1 6 — 6 2 42.9 Residential first mortgage 42 11 31 — 31 3 33.3 Home equity 10 1 9 — 9 — 10.0 Total consumer 52 12 40 — 40 3 28.8 $ 679 $ 109 $ 570 $ 49 $ 521 $ 149 38.0 % Accruing Impaired Loans 2017 Book Value (3) Unpaid Principal Balance (1) Charge-offs and Payments Applied (2) Total Impaired Loans on Accrual Status Impaired Loans on Accrual Status with No Related Allowance Impaired Loans on Accrual Status with Related Allowance Related Allowance for Loan Losses Coverage % (4) (Dollars in millions) Commercial and industrial $ 154 $ 8 $ 146 $ 1 $ 145 $ 19 17.5 % Commercial real estate mortgage—owner-occupied 90 5 85 — 85 8 14.4 Commercial real estate construction—owner-occupied 1 — 1 — 1 — — Total commercial 245 13 232 1 231 27 16.3 Commercial investor real estate mortgage 63 2 61 — 61 3 7.9 Commercial investor real estate construction 29 — 29 — 29 3 10.3 Total investor real estate 92 2 90 — 90 6 8.7 Residential first mortgage 419 13 406 — 406 39 12.4 Home equity 251 1 250 — 250 5 2.4 Consumer credit card 1 — 1 — 1 — — Other consumer 9 — 9 — 9 — — Total consumer 680 14 666 — 666 44 8.5 $ 1,017 $ 29 $ 988 $ 1 $ 987 $ 77 10.4 % Total Impaired Loans 2017 Book Value (3) Unpaid Principal Balance (1) Charge-offs and Payments Applied (2) Total Impaired Loans Impaired Loans with No Related Allowance Impaired Loans with Related Allowance Related Allowance for Loan Losses Coverage % (4) (Dollars in millions) Commercial and industrial $ 634 $ 88 $ 546 $ 30 $ 516 $ 122 33.1 % Commercial real estate mortgage—owner-occupied 223 20 203 20 183 46 29.6 Commercial real estate construction—owner-occupied 8 1 7 — 7 3 50.0 Total commercial 865 109 756 50 706 171 32.4 Commercial investor real estate mortgage 69 3 66 — 66 5 11.6 Commercial investor real estate construction 30 — 30 — 30 3 10.0 Total investor real estate 99 3 96 — 96 8 11.1 Residential first mortgage 461 24 437 — 437 42 14.3 Home equity 261 2 259 — 259 5 2.7 Consumer credit card 1 — 1 — 1 — — Other consumer 9 — 9 — 9 — — Total consumer 732 26 706 — 706 47 10.0 $ 1,696 $ 138 $ 1,558 $ 50 $ 1,508 $ 226 21.5 % Non-accrual Impaired Loans 2016 Book Value (3) Unpaid Principal Balance (1) Charge-offs and Payments Applied (2) Total Impaired Loans on Non-accrual Status Impaired Loans on Non-accrual Status with No Related Allowance Impaired Loans on Non-accrual Status with Related Allowance Related Allowance for Loan Losses Coverage % (4) (Dollars in millions) Commercial and industrial $ 685 $ 72 $ 613 $ 126 $ 487 $ 138 30.7 % Commercial real estate mortgage—owner-occupied 231 21 210 39 171 53 32.0 Commercial real estate construction—owner-occupied 4 1 3 — 3 2 75.0 Total commercial 920 94 826 165 661 193 31.2 Commercial investor real estate mortgage 18 1 17 5 12 5 33.3 Total investor real estate 18 1 17 5 12 5 33.3 Residential first mortgage 41 12 29 — 29 4 39.0 Home equity 12 1 11 — 11 — 8.3 Total consumer 53 13 40 — 40 4 32.1 $ 991 $ 108 $ 883 $ 170 $ 713 $ 202 31.3 % Accruing Impaired Loans 2016 Unpaid Principal Balance (1) Charge-offs and Payments Applied (2) Book Value (3) Related Allowance for Loan Losses Coverage % (4) (Dollars in millions) Commercial and industrial $ 187 $ 1 $ 186 $ 33 18.2 % Commercial real estate mortgage—owner-occupied 60 4 56 5 15.0 Commercial real estate construction—owner-occupied 1 — 1 — — Total commercial 248 5 243 38 17.3 Commercial investor real estate mortgage 82 8 74 7 18.3 Commercial investor real estate construction 16 — 16 1 6.3 Total investor real estate 98 8 90 8 16.3 Residential first mortgage 435 10 425 51 14.0 Home equity 292 — 292 5 1.7 Indirect—vehicles 1 — 1 — — Consumer credit card 2 — 2 — — Other consumer 10 — 10 — — Total consumer 740 10 730 56 8.9 $ 1,086 $ 23 $ 1,063 $ 102 11.5 % Total Impaired Loans 2016 Book Value (3) Unpaid Principal Balance (1) Charge-offs and Payments Applied (2) Total Impaired Loans Impaired Loans with No Related Allowance Impaired Loans with Related Allowance Related Allowance for Loan Losses Coverage % (4) (Dollars in millions) Commercial and industrial $ 872 $ 73 $ 799 $ 126 $ 673 $ 171 28.0 % Commercial real estate mortgage—owner-occupied 291 25 266 39 227 58 28.5 Commercial real estate construction—owner-occupied 5 1 4 — 4 2 60.0 Total commercial 1,168 99 1,069 165 904 231 28.3 Commercial investor real estate mortgage 100 9 91 5 86 12 21.0 Commercial investor real estate construction 16 — 16 — 16 1 6.3 Total investor real estate 116 9 107 5 102 13 19.0 Residential first mortgage 476 22 454 — 454 55 16.2 Home equity 304 1 303 — 303 5 2.0 Indirect—vehicles 1 — 1 — 1 — — Consumer credit card 2 — 2 — 2 — — Other consumer 10 — 10 — 10 — — Total consumer 793 23 770 — 770 60 10.5 $ 2,077 $ 131 $ 1,946 $ 170 $ 1,776 $ 304 20.9 % _________ (1) Unpaid principal balance represents the contractual obligation due from the customer and includes the net book value plus charge-offs and payments applied. (2) Charge-offs and payments applied represents cumulative partial charge-offs taken, as well as interest payments received that have been applied against the outstanding principal balance. (3) Book value represents the unpaid principal balance less charge-offs and payments applied; it is shown before any allowance for loan losses. (4) Coverage % represents charge-offs and payments applied plus the related allowance as a percent of the unpaid principal balance. The following table presents the average balances of total impaired loans and interest income for the years ended December 31, 2017 , 2016 and 2015 . Interest income recognized represents interest on accruing loans modified in a TDR. 2017 2016 2015 Average Interest Average Interest Average Interest (In millions) Commercial and industrial $ 747 $ 12 $ 714 $ 6 $ 386 $ 4 Commercial real estate mortgage—owner-occupied 226 5 304 5 345 9 Commercial real estate construction—owner-occupied 5 — 3 — 3 — Total commercial 978 17 1,021 11 734 13 Commercial investor real estate mortgage 81 4 120 8 242 11 Commercial investor real estate construction 39 2 30 1 24 1 Total investor real estate 120 6 150 9 266 12 Residential first mortgage 450 15 469 15 477 15 Home equity 280 14 322 16 354 18 Indirect—vehicles — — 1 — 1 — Consumer credit card 2 — 2 — 2 — Other consumer 9 1 11 1 14 1 Total consumer 741 30 805 32 848 34 Total impaired loans $ 1,839 $ 53 $ 1,976 $ 52 $ 1,848 $ 59 TROUBLED DEBT RESTRUCTURINGS Regions regularly modifies commercial and investor real estate loans in order to facilitate a workout strategy. Typical modifications include accommodations, such as renewals and forbearances. The majority of Regions’ commercial and investor real estate TDRs are the result of renewals of classified loans at an interest rate that is not considered to be a market interest rate. For smaller dollar commercial loans, Regions may periodically grant interest rate and other term concessions, similar to those under the consumer program described below. Regions works to meet the individual needs of consumer borrowers to stem foreclosure through its CAP. Regions designed the program to allow for customer-tailored modifications with the goal of keeping customers in their homes and avoiding foreclosure where possible. Modification may be offered to any borrower experiencing financial hardship regardless of the borrower’s payment status. Consumer TDRs primarily involve an interest rate concession, however under the CAP, Regions may also offer a short-term deferral, a term extension, a new loan product, or a combination of these options. For loans restructured under the CAP, Regions expects to collect the original contractually due principal. The gross original contractual interest may be collectible, depending on the terms modified. All CAP modifications are considered TDRs regardless of the term because they are concessionary in nature and because the customer documents a financial hardship in order to participate. As noted above, the majority of Regions’ TDRs are results of interest rate concessions and not a forgiveness of principal. Accordingly, the financial impact of the modifications is best illustrated by the impact to the allowance calculation at the loan or pool level, as a result of the loans being considered impaired due to their TDR status. Regions most often does not record a charge-off at the modification date. The following tables present the end of period balance for loans modified in a TDR during the periods presented by portfolio segment and class, and the financial impact of those modifications. The tables include modifications made to new TDRs, as well as renewals of existing TDRs. Loans first reported as TDRs for the years ended December 31, 2017 and 2016 totaled approximately $501 million and $542 million , respectively. 2017 Financial Impact of Modifications Considered TDRs Number of Obligors Recorded Investment Increase in Allowance at Modification (Dollars in millions) Commercial and industrial 134 $ 493 $ 10 Commercial real estate mortgage—owner-occupied 118 110 3 Commercial real estate construction—owner-occupied 3 2 — Total commercial 255 605 13 Commercial investor real estate mortgage 42 104 3 Commercial investor real estate construction 5 70 2 Total investor real estate 47 174 5 Residential first mortgage 209 39 5 Home equity 116 9 — Consumer credit card 68 1 — Indirect—vehicles and other consumer 155 2 — Total consumer 548 51 5 850 $ 830 $ 23 2016 Financial Impact of Modifications Considered TDRs Number of Obligors Recorded Investment Increase in Allowance at Modification (Dollars in millions) Commercial and industrial 184 $ 509 $ 12 Commercial real estate mortgage—owner-occupied 117 98 2 Commercial real estate construction—owner-occupied 1 1 — Total commercial 302 608 14 Commercial investor real estate mortgage 80 96 2 Commercial investor real estate construction 9 43 1 Total investor real estate 89 139 3 Residential first mortgage 231 46 6 Home equity 300 15 — Consumer credit card 88 1 — Indirect—vehicles and other consumer 190 2 — Total consumer 809 64 6 1,200 $ 811 $ 23 Defaulted TDRs The following table presents, by portfolio segment and class, TDRs that defaulted during the years ended December 31, 2017 and 2016 , and that were modified in the previous twelve months (i.e., the twelve months prior to the default). For purposes of this disclosure, default is defined as placement on non-accrual status for the commercial and investor real estate portfolio segments, and 90 days past due and still accruing for the consumer portfolio segment. Consideration of defaults in the calculation of the allowance for loan losses is described in detail in Note 1. 2017 2016 (In millions) Defaulted During the Period, Where Modified in a TDR Twelve Months Prior to Default Commercial and industrial $ 10 $ 28 Commercial real estate mortgage—owner-occupied 1 3 Total commercial 11 31 Commercial investor real estate mortgage — 3 Commercial investor real estate construction — 1 Total investor real estate — 4 Residential first mortgage 9 21 Home equity 1 2 Total consumer 10 23 $ 21 $ 58 Commercial and investor real estate loans that were on non-accrual status at the time of the latest modification are not included in the default table above, as they are already considered to be in default at the time of the restructuring. At December 31, 2017 , approximately $4 million of commercial and investor real estate loans modified in a TDR during the year ended December 31, 2017 were on non-accrual status. At December 31, 2017 , Regions had restructured binding unfunded commitments totaling $20 million where a concession was granted and the borrower was in financial difficulty.

Servicing of Financial Assets

Servicing of Financial Assets	12 Months Ended
	Dec. 31, 2017
Transfers and Servicing of Financial Assets [Abstract]
Servicing of Financial Assets	SERVICING OF FINANCIAL ASSETS RESIDENTIAL MORTGAGE BANKING ACTIVITIES The fair value of residential MSRs is calculated using various assumptions including future cash flows, market discount rates, expected prepayment rates, servicing costs and other factors. A significant change in prepayments of mortgages in the servicing portfolio could result in significant changes in the valuation adjustments, thus creating potential volatility in the carrying amount of residential MSRs. The Company compares fair value estimates and assumptions to observable market data where available, and also considers recent market activity and actual portfolio experience. The table below presents an analysis of residential MSRs under the fair value measurement method for the years ended December 31 : 2017 2016 2015 (In millions) Carrying value, beginning of year $ 324 $ 252 $ 257 Additions 64 108 36 Increase (decrease) in fair value (1) : Due to change in valuation inputs or assumptions (8 ) 4 (2 ) Economic amortization associated with borrower repayments (44 ) (40 ) (39 ) Carrying value, end of year $ 336 $ 324 $ 252 _________ (1) "Economic amortization associated with borrower repayments" includes both total loan payoffs as well as partial paydowns. On April 30, 2015, the Company purchased the rights to service approximately $380 million in residential mortgage loans for approximately $4 million . On February 29, 2016, the Company purchased the rights to service approximately $2.6 billion in residential mortgage loans for approximately $24 million . On September 1, 2016, the Company purchased the rights to service approximately $2.8 billion in residential mortgage loans for approximately $22 million . On November 30, 2016, the Company purchased the rights to service approximately $2.2 billion in residential mortgage loans for approximately $23 million . However, the Company paid $18 million as of December 31, 2016, and the balance of $5 million was paid in 2017. On April 28, 2017, the Company purchased the rights to service approximately $2.7 billion in residential mortgage loans for approximately $30 million . Data and assumptions used in the fair value calculation, as well as the valuation’s sensitivity to rate fluctuations, related to residential MSRs (excluding related derivative instruments) as of December 31 are as follows: 2017 2016 (Dollars in millions) Unpaid principal balance $ 32,076 $ 31,335 Weighted-average CPR (%) 9.9 % 7.6 % Estimated impact on fair value of a 10% increase $ (22 ) $ (19 ) Estimated impact on fair value of a 20% increase $ (39 ) $ (34 ) Option-adjusted spread (basis points) 861 1,054 Estimated impact on fair value of a 10% increase $ (11 ) $ (13 ) Estimated impact on fair value of a 20% increase $ (22 ) $ (27 ) Weighted-average coupon interest rate 4.1 % 4.2 % Weighted-average remaining maturity (months) 281 281 Weighted-average servicing fee (basis points) 27.4 27.5 The sensitivity calculations above are hypothetical and should not be considered to be predictive of future performance. Changes in fair value based on adverse changes in assumptions generally cannot be extrapolated because the relationship of the change in assumption to the change in fair value may not be linear. Also, the effect of an adverse variation in a particular assumption on the fair value of the residential MSRs is calculated without changing any other assumption, while in reality changes in one factor may result in changes in another, which may either magnify or counteract the effect of the change. The derivative instruments utilized by Regions would serve to reduce the estimated impacts to fair value included in the table above. The following table presents servicing related fees, which includes contractually specified servicing fees, late fees and other ancillary income resulting from the servicing of residential mortgage loans for the years ended December 31 : 2017 2016 2015 (In millions) Servicing related fees and other ancillary income $ 96 $ 86 $ 82 Residential mortgage loans are sold in the secondary market with standard representations and warranties regarding certain characteristics such as the quality of the loan, the absence of fraud, the eligibility of the loan for sale and the future servicing associated with the loan. Regions may be required to repurchase these loans at par, or make-whole or indemnify the purchasers for losses incurred when representations and warranties are breached. Regions maintains an immaterial repurchase liability related to residential mortgage loans sold with representations and warranty provisions. This repurchase liability is reported in other liabilities on the consolidated balance sheets and reflects management’s estimate of losses based on historical repurchase and loss trends, as well as other factors that may result in anticipated losses different from historical loss trends. Adjustments to this reserve are recorded in other non-interest expense on the consolidated statements of income. COMMERCIAL MORTGAGE BANKING ACTIVITIES On July 18, 2014, Regions was approved as a DUS lender and acquired a DUS servicing portfolio totaling approximately $1.0 billion . The DUS program provides liquidity to the multi-family housing market. As part of the transaction, Regions recorded $12 million in commercial MSRs and $15 million in intangible assets associated with the DUS license purchased. Regions also assumed a loss share guarantee associated with the purchased portfolio and any future originations. Regions estimated the fair value of the loss share guarantee to be approximately $4 million . See Note 1 for additional information. Also see Note 24 for additional information related to the guarantee. As of December 31, 2017 and 2016 the DUS servicing portfolio was approximately $2.9 billion and $1.8 billion , respectively. The related commercial MSRs were approximately $48 million and $30 million at December 31, 2017 and 2016, respectively. The estimated fair value of the loss share guarantee was approximately $4 million at both December 31, 2017 and 2016.

Other Earning Assets

Other Earning Assets	12 Months Ended
	Dec. 31, 2017
Other Earning Assets [Abstract]
Other Earning Assets	OTHER EARNING ASSETS Other earning assets consist primarily of investments in FRB stock, FHLB stock, and operating lease assets. The following table presents the amount of Regions' investments in FRB and FHLB stock as of December 31: 2017 2016 (In millions) Federal Reserve Bank $ 492 $ 494 Federal Home Loan Bank 192 196 The Company's investments in operating leases represent assets such as equipment, vehicles and aircraft. The following table presents investments in operating leases at December 31: 2017 2016 (In millions) Lease assets $ 685 $ 818 Accumulated depreciation (196 ) (130 ) Investments in operating leases, net $ 489 $ 688 The following table presents the minimum future rental payments due from customers for operating leases as of December 31: Future rental payments (In millions) 2018 $ 74 2019 59 2020 44 2021 30 2022 17 Thereafter 20 $ 244

Premises and Equipment

Premises and Equipment	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Premises and Equipment	PREMISES AND EQUIPMENT A summary of premises and equipment at December 31 is as follows: 2017 2016 (In millions) Land $ 484 $ 490 Premises and improvements 1,751 1,730 Furniture and equipment 982 1,025 Software 624 597 Leasehold improvements 388 387 Construction in progress 249 214 4,478 4,443 Accumulated depreciation and amortization (2,414 ) (2,347 ) $ 2,064 $ 2,096

Intangible Assets

Intangible Assets	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets	INTANGIBLE ASSETS GOODWILL Goodwill allocated to each reportable segment at December 31 is presented as follows: 2017 2016 (In millions) Corporate Bank $ 2,474 $ 2,474 Consumer Bank 1,978 1,978 Wealth Management 452 452 $ 4,904 $ 4,904 During the fourth quarter of 2017 , Regions assessed the indicators of goodwill impairment for all three reporting units as part of its annual impairment test, as of October 1, 2017 , and through the date of the filing of this Annual Report. The results of the annual test indicated that the estimated fair value of each reporting unit exceeded its carrying amount as of the test date; therefore, the goodwill of each reporting unit is considered not impaired as of the testing date. Listed in the tables below are assumptions used in estimating the fair value of each reporting unit for the applicable annual period. The table includes the discount rates used in the income approach, the market multipliers used in the market approaches, and the public company method control premium applied to each reporting unit. These valuation approaches are described further in Note 1. As of Fourth Quarter 2017 Corporate Bank Consumer Bank Wealth Management Discount rate used in income approach 11.25 % 11.00 % 11.25 % Public company method market multiplier (1) 1.8x 2.0x 18.8x Transaction method market multiplier (2) 1.9x 2.6x 24.2x As of Fourth Quarter 2016 Corporate Bank Consumer Bank Wealth Management Discount rate used in income approach 10.00 % 10.25 % 11.50 % Public company method market multiplier (1) 1.5x 1.9x 14.6x Transaction method market multiplier (2) 1.9x 1.9x 23.5x _______ (1) For the Corporate Bank and Consumer Bank reporting units, these multipliers are applied to tangible book value. For the Wealth Management reporting unit, this multiplier is applied to earnings. In addition to the multipliers, a 10 percent control premium was assumed for the Corporate Bank reporting unit, and a 25 percent control premium was assumed for the Consumer Bank and the Wealth Management reporting units based on current market factors. Because the control premium considers potential revenue synergies and cost savings for similar financial services transactions, reporting units operating in businesses that have greater barriers to entry tend to have greater control premiums. (2) For the Corporate Bank and Consumer Bank reporting units, these multipliers are applied to tangible book value. For the Wealth Management reporting unit, this multiplier is applied to earnings. OTHER INTANGIBLES Other intangibles consist primarily of core deposit intangibles, purchased credit card relationship assets, customer relationship and employment agreement assets and the DUS license. The following table shows the other intangibles and related accumulated amortization as of December 31: 2017 2016 2017 2016 2017 2016 Gross Carrying Amount Accumulated Amortization Net Carrying Amount (In millions) Core deposit intangibles $ 1,011 $ 1,011 $ 950 $ 932 $ 61 $ 79 Purchased credit card relationship assets 175 175 116 102 59 73 Customer relationship and employment agreement assets 75 75 43 33 32 42 Other—amortizing (1) 19 19 12 10 7 9 FNMA DUS license (2) 15 15 Other—non-amortizing (3) 3 3 $ 1,280 $ 1,280 $ 1,121 $ 1,077 $ 177 $ 221 _________ (1) Includes intangible assets related to acquired trust services, trade names and intellectual property. (2) The DUS license is a non-amortizing intangible asset. (3) Includes non-amortizing intangible assets related to other acquired trust services. Purchased credit card relationships and customer relationships and employment agreements are being amortized in other non-interest expense primarily on an accelerated basis over a period ranging from 2 to 15 years. Core deposit intangible assets are being amortized in other non-interest expense on an accelerated basis over their expected useful lives. Regions purchased a DUS license in 2014. The intangible asset associated with the DUS license is a non-amortizing intangible asset. Refer to Note 7 for additional information related to this license. The aggregate amount of amortization expense for core deposit intangibles, purchased credit card relationship assets, and other intangible assets is estimated as follows: Year Ended December 31 (In millions) 2018 $ 39 2019 32 2020 26 2021 21 2022 17 Identifiable intangible assets other than goodwill are reviewed at least annually, usually in the fourth quarter, for events or circumstances that could impact the recoverability of the intangible asset. Regions concluded that no impairment for any other identifiable intangible assets occurred during 2017 , 2016 or 2015 .

Deposits

Deposits	12 Months Ended
	Dec. 31, 2017
Deposits [Abstract]
Deposits	DEPOSITS The following schedule presents a detail of interest-bearing deposits at December 31 : 2017 2016 (In millions) Savings $ 8,413 $ 7,840 Interest-bearing transaction 20,161 20,259 Money market—domestic 25,306 27,293 Money market—foreign 23 186 Time deposits 6,859 7,183 Interest-bearing customer deposits 60,762 62,761 Corporate treasury time deposits — 228 $ 60,762 $ 62,989 The aggregate amount of time deposits of $250,000 or more, including certificates of deposit of $250,000 or more, was $1.3 billion and $1.2 billion at December 31, 2017 and 2016 , respectively. At December 31, 2017 , the aggregate amounts of maturities of all time deposits (deposits with stated maturities, consisting primarily of certificates of deposit and IRAs) were as follows: December 31, 2017 (In millions) 2018 $ 3,207 2019 940 2020 1,237 2021 893 2022 345 Thereafter 237 $ 6,859

Short-Term Borrowings

Short-Term Borrowings	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Short-Term Borrowings	SHORT-TERM BORROWINGS Following is a summary of short-term borrowings at December 31 : 2017 2016 (In millions) Company funding sources: FHLB advances $ 500 $ — $ 500 $ —

Long-Term Borrowings

Long-Term Borrowings	12 Months Ended
	Dec. 31, 2017
Long-term Borrowings [Abstract]
Long-Term Borrowings	LONG-TERM BORROWINGS Long-term borrowings at December 31 consist of the following: 2017 2016 (In millions) Regions Financial Corporation (Parent): 2.00% senior notes due May 2018 $ 101 $ 100 3.20% senior notes due February 2021 1,101 1,102 2.75% senior notes due August 2022 995 — 7.75% subordinated notes due September 2024 100 100 6.75% subordinated debentures due November 2025 158 159 7.375% subordinated notes due December 2037 297 297 Valuation adjustments on hedged long-term debt (50 ) (30 ) 2,702 1,728 Regions Bank: FHLB advances 3,653 4,254 2.25% senior notes due September 2018 749 748 7.50% subordinated notes due May 2018 500 499 6.45% subordinated notes due June 2037 495 495 3.80% affiliate subordinated notes due February 2025 — 150 Other long-term debt 35 40 Valuation adjustments on hedged long-term debt (2 ) (1 ) 5,430 6,185 Elimination of 3.80% affiliate subordinated notes due February 2025 — (150 ) Total consolidated $ 8,132 $ 7,763 As of December 31, 2017 , Regions had five issuances of subordinated notes totaling $1.6 billion , with stated interest rates ranging from 6.45% to 7.75% . All issuances of these notes are, by definition, subordinated and subject in right of payment of both principal and interest to the prior payment in full of all senior indebtedness of the Company, which is generally defined as all indebtedness and other obligations of the Company to its creditors, except subordinated indebtedness. Payment of the principal of the notes may be accelerated only in the case of certain events involving bankruptcy, insolvency proceedings or reorganization of the Company. The subordinated notes described above qualify as Tier 2 capital under Federal Reserve guidelines, subject to diminishing credit as the respective maturity dates approach and subject to certain transition provisions. None of the subordinated notes are redeemable prior to maturity, unless there is an occurrence of a qualifying capital event. The 3.80% affiliate subordinated notes were repaid during 2017. On August 14, 2017, Regions issued $1.0 billion of 2.75% senior notes, which are due August 14, 2022. FHLB advances at December 31, 2017 , 2016 and 2015 had a weighted-average interest rate of 1.4 percent , 0.8 percent , and 0.7 percent , respectively, with remaining maturities ranging from less than one year to thirteen years and a weighted-average of 0.8 years. FHLB borrowing capacity is contingent upon the amount of collateral pledged to the FHLB. Regions has pledged certain loans as collateral for the FHLB advances outstanding. See Note 5 for loans pledged to the FHLB at December 31, 2017 and 2016 . Additionally, membership in the FHLB requires an institution to hold FHLB stock. See Note 8 for the amount of FHLB stock held at December 31, 2017 and 2016 . Regions’ total borrowing capacity with the FHLB (including outstanding advances) as of December 31, 2017 , based on assets available for collateral at that date, was approximately $17.2 billion . Regions uses derivative instruments, primarily interest rate swaps, to manage interest rate risk by converting a portion of its fixed-rate debt to a variable-rate. The effective rate adjustments related to these hedges are included in interest expense on long-term borrowings. The weighted-average interest rate on total long-term debt, including the effect of derivative instruments, was 3.0 percent , 2.4 percent , and 3.1 percent for the years ended December 31, 2017 , 2016 and 2015 , respectively. Further discussion of derivative instruments is included in Note 21. The aggregate amount of contractual maturities of all long-term debt in each of the next five years and thereafter is as follows: Year Ended December 31 Regions Financial Corporation (Parent) Regions Bank (In millions) 2018 $ 101 $ 4,899 2019 — 4 2020 — 30 2021 1,066 1 2022 980 — Thereafter 555 496 $ 2,702 $ 5,430 In February 2016, Regions filed a shelf registration statement with the SEC. This shelf registration does not have a capacity limit and can be utilized by Regions to issue various debt and/or equity securities. The registration statement will expire in February 2019. Regions Bank may issue bank notes from time to time, either as part of a bank note program or as stand-alone issuances. Notes issued by Regions Bank may be senior or subordinated notes. Notes issued by Regions Bank are not deposits and are not insured or guaranteed by the FDIC. Regions may, from time to time, consider opportunistically retiring outstanding issued securities, including subordinated debt in privately negotiated or open market transactions. Regulatory approval would be required for retirement of some securities. On January 23, 2018, Regions issued $550 million of 2.75% senior bank notes and $350 million of senior floating rate bank notes at three-month LIBOR plus 38 basis points, both of which are due April 1, 2021. The Company simultaneously entered into an interest rate swap effectively converting the 2.75% senior bank notes to floating rate notes at one-month LIBOR.

Regulatory Capital Requirements

Regulatory Capital Requirements and Restrictions	12 Months Ended
	Dec. 31, 2017
Banking and Thrift [Abstract]
Regulatory Capital Requirements and Restrictions	REGULATORY CAPITAL REQUIREMENTS AND RESTRICTIONS Regions and Regions Bank are required to comply with regulatory capital requirements established by federal and state banking agencies. These regulatory capital requirements involve quantitative measures of the Company’s assets, liabilities and certain off-balance sheet items, and also qualitative judgments by the regulators. Failure to meet minimum capital requirements can subject the Company to a series of increasingly restrictive regulatory actions. Banking regulations identify five capital categories: well-capitalized, adequately capitalized, undercapitalized, significantly undercapitalized and critically undercapitalized. At December 31, 2017 and 2016 , Regions and Regions Bank exceeded all current regulatory requirements, and were classified as "well-capitalized." Management believes that no events or changes have occurred subsequent to December 31, 2017 that would change this designation. Quantitative measures established by regulation to ensure capital adequacy require institutions to maintain minimum ratios of common equity Tier 1, Tier 1, and Total capital (as defined in the regulations) to risk-weighted assets (as defined), and of Tier 1 capital to average tangible assets (the "Leverage" ratio). The following tables summarize the applicable holding company and bank regulatory capital requirements: December 31, 2017 (1) Minimum Requirement To Be Well Capitalized Amount Ratio Transitional Basis Basel III Regulatory Capital Rules (2) (Dollars in millions) Basel III common equity Tier 1 capital: Regions Financial Corporation $ 11,152 11.05 % 4.50 % N/A Regions Bank 12,560 12.49 4.50 6.50 % Tier 1 capital: Regions Financial Corporation $ 11,964 11.86 % 6.00 % 6.00 % Regions Bank 12,560 12.49 6.00 8.00 Total capital: Regions Financial Corporation $ 13,903 13.78 % 8.00 % 10.00 % Regions Bank 14,042 13.97 8.00 10.00 Leverage capital: Regions Financial Corporation $ 11,964 10.01 % 4.00 % N/A Regions Bank 12,560 10.54 4.00 5.00 % December 31, 2016 Minimum Requirement To Be Well Capitalized Amount Ratio Transitional Basis Basel III Regulatory Capital Rules (2) (Dollars in millions) Basel III common equity Tier 1 capital: Regions Financial Corporation $ 11,481 11.21 % 4.50 % N/A Regions Bank 12,404 12.14 4.50 6.50 % Tier 1 capital: Regions Financial Corporation $ 12,277 11.98 % 6.00 % 6.00 % Regions Bank 12,404 12.14 6.00 8.00 Total capital: Regions Financial Corporation $ 14,501 14.15 % 8.00 % 10.00 % Regions Bank 14,311 14.00 8.00 10.00 Leverage capital: Regions Financial Corporation $ 12,277 10.20 % 4.00 % N/A Regions Bank 12,404 10.34 4.00 5.00 % _________ (1) The 2017 Basel III CET1 capital, Tier 1 capital, Total capital, and Leverage capital ratios are estimated. (2) The 2017 and 2016 capital ratios were calculated at different points of the phase-in period under the Basel III Rules and therefore are not directly comparable. Substantially all net assets are owned by subsidiaries. The primary source of operating cash available to Regions is provided by dividends from subsidiaries. Statutory limits are placed on the amount of dividends the subsidiary bank can pay without prior regulatory approval. In addition, regulatory authorities require the maintenance of minimum capital-to-asset ratios at banking subsidiaries. Under the Federal Reserve’s Regulation H, Regions Bank may not, without approval of the Federal Reserve, declare or pay a dividend to Regions if the total of all dividends declared in a calendar year exceeds the total of (a) Regions Bank’s net income for that year and (b) its retained net income for the preceding two calendar years, less any required transfers to additional paid-in capital or to a fund for the retirement of preferred stock. Under Alabama law, Regions Bank may not pay a dividend to Regions in excess of 90 percent of its net earnings until the bank’s surplus is equal to at least 20 percent of capital. Regions Bank is also required by Alabama law to seek the approval of the Alabama Superintendent of Banking prior to paying a dividend to Regions if the total of all dividends declared by Regions Bank in any calendar year will exceed the total of (a) Regions Bank’s net earnings for that year, plus (b) its retained net earnings for the preceding two years, less any required transfers to surplus. The statute defines net earnings as “the remainder of all earnings from current operations plus actual recoveries on loans and investments and other assets, after deducting from the total thereof all current operating expenses, actual losses, accrued dividends on preferred stock, if any, and all federal, state and local taxes.” In addition to dividend restrictions, Federal statutes also prohibit unsecured loans from banking subsidiaries to the parent company. In addition, Regions must adhere to various HUD regulatory guidelines including required minimum capital to maintain their FHA approved status. Failure to comply with the HUD guidelines could result in withdrawal of this certification. As of December 31, 2017 , Regions was in compliance with HUD guidelines. Regions is also subject to various capital requirements by secondary market investors.

Stockholders' Equity and Accumu

Stockholders' Equity and Accumulated Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Stockholders' Equity and Accumulated Other Comprehensive Income (Loss)	STOCKHOLDERS’ EQUITY AND ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) PREFERRED STOCK The following table presents a summary of the non-cumulative perpetual preferred stock as of December 31: 2017 2016 Issuance Date Earliest Redemption Date Dividend Rate Liquidation Amount Carrying Amount Carrying Amount (Dollars in millions) Series A 11/1/2012 12/15/2017 6.375 % $ 500 $ 387 $ 387 Series B 4/29/2014 9/15/2024 6.375 % (1) 500 433 433 $ 1,000 $ 820 $ 820 _________ (1) Dividends, if declared, will be paid quarterly at an annual rate equal to (i) for each period beginning prior to September 15, 2024, 6.375% , and (ii) for each period beginning on or after September 15, 2024, three-month LIBOR plus 3.536% . For each preferred stock issuance listed above, Regions issued depositary shares, each representing a 1/40th ownership interest in a share of the Company's preferred stock, with a liquidation preference of $1,000.00 per share of preferred stock (equivalent to $25.00 per depositary share). Dividends on the preferred stock, if declared, accrue and are payable quarterly in arrears. The preferred stock has no stated maturity and redemption is solely at Regions' option, subject to regulatory approval, in whole, or in part, after the earliest redemption date or in whole, but not in part, within 90 days following a regulatory capital treatment event for the Series A preferred stock or at any time following a regulatory capital treatment event for the Series B preferred stock. The Board of Directors declared $32 million in cash dividends on both Series A and Series B Preferred Stock, during both 2017 and 2016. In the event Series A and Series B preferred shares are redeemed at the liquidation amounts, $113 million and $67 million excess of the redemption amount over the carrying amount will be recognized, respectively. Approximately $100 million of Series A preferred dividends that were recorded as a reduction of preferred stock, including related surplus, will be recorded as a reduction to retained earnings, and approximately $13 million of related issuance costs that were recorded as a reduction of preferred stock, including related surplus, will be recorded as a reduction to net income available to common shareholders. Approximately $52 million of Series B preferred dividends that were recorded as a reduction of preferred stock, including related surplus, will be recorded as a reduction to retained earnings, and approximately $15 million of related issuance costs that were recorded as a reduction of preferred stock, including related surplus, will be recorded as a reduction to net income available to common shareholders. COMMON STOCK On June 28, 2017, Regions received no objection from the Federal Reserve to its 2017 capital plan that was submitted as part of the CCAR process, which included the repurchase of common shares and a common stock dividend increase. As part of the Company's capital plan, the Board authorized a new $1.47 billion common stock repurchase plan, permitting repurchases from the beginning of the third quarter of 2017 through the second quarter of 2018. The capital plan also included a proposed increase of the quarterly common stock dividend to $0.09 per common share beginning in the third quarter of 2017, subject to quarterly Board approval. The Board declared $0.315 per share in cash dividends for 2017, $0.255 for 2016, and $0.23 for 2015. Prior to the first quarter of 2016, the Company was in a retained deficit position and common stock dividends were recorded as a reduction of additional paid-in capital. During the first quarter of 2016, the Company achieved positive retained earnings and common stock dividends were recorded as a reduction of retained earnings since then. As of December 31, 2017, Regions had repurchased approximately 65.7 million shares of common stock at a total cost of approximately $1.0 billion under this plan. The Company continued to repurchase shares under this plan in the first quarter of 2018, and as of February 21, 2018, Regions had additional repurchases of approximately 12.5 million shares of common stock at a total cost of approximately $235.0 million . All of these shares were immediately retired upon repurchase and therefore will not be included in treasury stock. ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) Activity within the balances in accumulated other comprehensive income (loss) is shown in the following tables for the years ended December 31: 2017 Unrealized losses on securities transferred to held to maturity Unrealized gains (losses) on securities available for sale Unrealized gains (losses) on derivative instruments designated as cash flow hedges Defined benefit pension plans and other post employment benefits Accumulated other comprehensive income (loss), net of tax (In millions) Beginning of year $ (33 ) $ (106 ) $ 11 $ (422 ) $ (550 ) Net change 6 (12 ) (51 ) (9 ) (66 ) Reclassification of the Tax Reform related revaluation of deferred tax items within AOCI (6 ) (35 ) (11 ) (81 ) (133 ) End of year $ (33 ) $ (153 ) $ (51 ) $ (512 ) $ (749 ) 2016 Unrealized losses on securities transferred to held to maturity Unrealized gains (losses) on securities available for sale Unrealized gains (losses) on derivative instruments designated as cash flow hedges Defined benefit pension plans and other post employment benefits Accumulated other comprehensive income (loss), net of tax (In millions) Beginning of year $ (47 ) $ (10 ) $ 75 $ (398 ) $ (380 ) Net change 14 (96 ) (64 ) (24 ) (170 ) End of year $ (33 ) $ (106 ) $ 11 $ (422 ) $ (550 ) 2015 Unrealized losses on securities transferred to held to maturity Unrealized gains (losses) on securities available for sale Unrealized gains (losses) on derivative instruments designated as cash flow hedges Defined benefit pension plans and other post employment benefits Accumulated other (In millions) Beginning of year $ (55 ) $ 175 $ 33 $ (391 ) $ (238 ) Net change 8 (185 ) 42 (7 ) (142 ) End of year $ (47 ) $ (10 ) $ 75 $ (398 ) $ (380 ) The following table presents amounts reclassified out of accumulated other comprehensive income (loss) for the years ended December 31: 2017 2016 2015 Details about Accumulated Other Comprehensive Income (Loss) Components Amount Reclassified from Accumulated Other Comprehensive Income (Loss) (1) Amount Reclassified from Accumulated Other Comprehensive Income (Loss) (1) Amount Reclassified from Accumulated Other Comprehensive Income (Loss) (1) Affected Line Item in the Consolidated Statements of Income (In millions) Unrealized losses on securities transferred to held to maturity: $ (10 ) $ (22 ) $ (14 ) Net interest income and other financing income 4 8 6 Tax (expense) or benefit $ (6 ) $ (14 ) $ (8 ) Net of tax Unrealized gains and (losses) on available for sale securities: $ 19 $ 6 $ 29 Securities gains, net (7 ) (2 ) (10 ) Tax (expense) or benefit $ 12 $ 4 $ 19 Net of tax Gains (losses) on cash flow hedges: Interest rate contracts $ 86 $ 143 $ 153 Net interest income and other financing income (33 ) (54 ) (58 ) Tax (expense) or benefit $ 53 $ 89 $ 95 Net of tax Amortization of defined benefit pension plans and other post employment benefits: Prior service cost $ — $ — $ (1 ) (2) Actuarial gains (losses) and settlements (48 ) (34 ) (47 ) (2) (48 ) (34 ) (48 ) Total before tax 17 12 17 Tax (expense) or benefit $ (31 ) $ (22 ) $ (31 ) Net of tax Total reclassifications for the period $ 28 $ 57 $ 75 Net of tax _________ (1) Amounts in parentheses indicate reductions to net income. (2) These accumulated other comprehensive income (loss) components are included in the computation of net periodic pension cost and are included in salaries and employee benefits on the consolidated statements of income (see Note 18 for additional details).

Earnings (Loss) per Common Shar

Earnings (Loss) per Common Share	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Earnings (Loss) per Common Share	EARNINGS (LOSS) PER COMMON SHARE The following table sets forth the computation of basic earnings (loss) per common share and diluted earnings (loss) per common share for the years ended December 31 : 2017 2016 2015 (In millions, except per share data) Numerator: Income from continuing operations $ 1,257 $ 1,158 $ 1,075 Preferred stock dividends (64 ) (64 ) (64 ) Income from continuing operations available to common shareholders 1,193 1,094 1,011 Income (loss) from discontinued operations, net of tax 6 5 (13 ) Net income available to common shareholders $ 1,199 $ 1,099 $ 998 Denominator: Weighted-average common shares outstanding—basic 1,186 1,255 1,325 Potential common shares 12 6 9 Weighted-average common shares outstanding—diluted 1,198 1,261 1,334 Earnings per common share from continuing operations available to common shareholders (1) : Basic $ 1.01 $ 0.87 $ 0.76 Diluted 1.00 0.87 0.76 Earnings (loss) per common share from discontinued operations (1) : Basic $ 0.01 $ 0.00 $ (0.01 ) Diluted 0.00 0.00 (0.01 ) Earnings per common share (1) : Basic $ 1.01 $ 0.87 $ 0.75 Diluted 1.00 0.87 0.75 ________ (1) Certain per share amounts may not appear to reconcile due to rounding. For earnings per common share from discontinued operations, basic and diluted weighted-average common shares are the same for 2015 due to the Company experiencing net losses from discontinued operations. The effect from the assumed exercise of 14 million , 27 million and 29 million in stock options, restricted stock units and awards and performance stock units for the years ended December 31, 2017 , 2016 and 2015 , respectively, was not included in the above computations of diluted earnings per common share because such amounts would have had an antidilutive effect on earnings per common share.

Share-Based Payments

Share-Based Payments	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Payments	SHARE-BASED PAYMENTS Regions administers long-term incentive compensation plans that permit the granting of incentive awards in the form of stock options, restricted stock awards, performance awards and stock appreciation rights. While Regions has the ability to issue stock appreciation rights, none have been issued to date. The terms of all awards issued under these plans are determined by the Compensation Committee of the Board; however, no awards may be granted after the tenth anniversary from the date the plans were initially approved by stockholders. Incentive awards usually vest based on employee service, generally within three years from the date of the grant. The contractual lives of options granted under these plans are typically ten years from the date of the grant. On April 23, 2015, the stockholders of the Company approved the Regions Financial Corporation 2015 LTIP, which permits the Company to grant to employees and directors various forms of incentive compensation. These forms of incentive compensation are similar to the types of compensation approved in prior plans. The 2015 LTIP authorizes 60 million common share equivalents available for grant, where grants of options and grants of full value awards (e.g., shares of restricted stock, restricted stock units and performance stock units) count as one share equivalent. Unless otherwise determined by the Compensation Committee of the Board, grants of restricted stock, restricted stock units, and performance stock units accrue dividends, or their notional equivalent, as they are declared by the Board, and are paid upon vesting of the award. Upon adoption of the 2015 LTIP, Regions closed the prior long-term incentive plan to new grants, and, accordingly, prospective grants must be made under the 2015 LTIP or a successor plan. All existing grants under prior long-term incentive plans are unaffected by adoption of the 2015 LTIP. The number of remaining share equivalents available for future issuance under the 2015 LTIP was approximately 45 million at December 31, 2017 . Grants of performance-based restricted stock typically have a three -year performance period, and shares vest within three years after the grant date. Restricted stock units typically have a vesting period of three years. Grantees of restricted stock awards or units must either remain employed with the Company for certain periods from the date of grant in order for shares to be released or issued or retire after meeting the standards of a retiree, at which time shares would be issued and released. The terms of these plans generally stipulate that the exercise price of options may not be less than the fair market value of Regions' common stock at the date the options are granted. The contractual life of options granted under these plans is typically ten years from the date of grant. Regions issues new shares from authorized reserves upon exercise. The following table summarizes the elements of compensation cost recognized in the consolidated statements of income for the years ended December 31 : 2017 2016 2015 (In millions) Compensation cost of share-based compensation awards: Restricted and performance stock awards $ 62 $ 52 $ 50 Tax benefits related to share-based compensation cost (1) (23 ) (20 ) (19 ) Compensation cost of share-based compensation awards, net of tax $ 39 $ 32 $ 31 ________ (1) The tax benefits rela ted to share-based compensation cost for 2017 exclude (a) excess tax benefits of $10 million related to settled share-based compensation awards and (b) tax expense of $5 million related to expired stock options. STOCK OPTIONS The following table summarizes the activity for 2017 , 2016 and 2015 related to stock options: Number of Options Weighted- Average Exercise Price Aggregate Intrinsic Value (In millions) Weighted-Average Remaining Contractual Term Outstanding at December 31, 2014 25,316,676 $ 23.07 $ 28 2.83 yrs. Granted — — Exercised (546,455 ) 6.93 Forfeited or expired (5,420,064 ) 31.88 Outstanding at December 31, 2015 19,350,157 $ 21.06 $ 20 2.45 yrs. Granted — — Exercised (1,954,064 ) 5.80 Forfeited or expired (3,941,046 ) 34.39 Outstanding at December 31, 2016 13,455,047 $ 19.37 $ 34 1.83 yrs. Granted — — Exercised (1,204,138 ) 6.69 Forfeited or expired (2,843,011 ) 34.00 Outstanding at December 31, 2017 9,407,898 $ 16.58 $ 35 1.05 yrs. Exercisable at December 31, 2017 9,407,898 $ 16.58 $ 35 1.05 yrs. The aggregate intrinsic value of exercised options was $13 million for 2017 , $17 million for 2016 , and $5 million for 2015 . Cash received from options exercised was $8 million , $11 million , and $4 million in 2017 , 2016 , and 2015 , respectively. The actual tax benefit realized for the tax deductions from options exercised totaled $3 million for 2017 , $4 million for 2016 , and $1 million for 2015 . RESTRICTED STOCK AWARDS AND PERFORMANCE STOCK AWARDS During 2017 , 2016 and 2015 , Regions made restricted stock grants that vest upon satisfaction of service conditions and restricted stock award and performance stock award grants that vest based upon service conditions and performance conditions. Incremental shares earned above the performance target associated with previous performance stock awards are included when and if performance targets are achieved. Dividend payments during the vesting period are deferred to the end of the vesting term. The fair value of these restricted shares, restricted stock units and performance stock units was estimated based upon the fair value of the underlying shares on the date of the grant. The valuation was not adjusted for the deferral of dividends. Activity related to restricted stock awards and performance stock awards for 2017 , 2016 and 2015 is summarized as follows: Number of Shares/Units Weighted-Average Grant Date Fair Value Non-vested at December 31, 2014 18,427,409 $ 8.07 Granted 6,670,905 9.22 Vested (8,222,576 ) 6.09 Forfeited (501,496 ) 8.81 Non-vested at December 31, 2015 16,374,242 $ 9.51 Granted 6,867,672 7.93 Vested (5,829,974 ) 8.28 Forfeited (852,998 ) 9.07 Non-vested at December 31, 2016 16,558,942 $ 9.31 Granted 3,993,591 14.57 Vested (4,657,544 ) 11.06 Forfeited (631,955 ) 10.04 Non-vested at December 31, 2017 15,263,034 $ 10.12 As of December 31, 2017 , the pre-tax amount of non-vested restricted stock, restricted stock units and performance stock units not yet recognized was $54 million , which will be recognized over a weighted-average period of 1.72 years. The total fair value of shares vested during the years ended December 31, 2017 , 2016 , and 2015 , was $68 million , $47 million , and $82 million , respectively. No share-based compensation costs were capitalized during the years ended December 31, 2017 , 2016 and 2015 .

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2017
Defined Benefit Plan [Abstract]
Employee Benefit Plans	EMPLOYEE BENEFIT PLANS PENSION AND OTHER POSTRETIREMENT BENEFITS Effective January 1, 2016, Regions separated its defined benefit pension plan qualified under the Internal Revenue Code into two plans. The new plan was created primarily for participants who were actively employed on January 1, 2016 and all other participants were retained in the existing plan. Regions' defined benefit pension plans cover only certain employees as the pension plans are closed to new entrants. Benefits under the pension plans are based on years of service and the employee’s highest five consecutive years of compensation during the last ten years of employment. Regions’ funding policy is to contribute annually at least the amount required by IRS minimum funding standards. Contributions are intended to provide not only for benefits attributed to service to date, but also for those expected to be earned in the future. The Company also sponsors a SERP, which is a non-qualified pension plan that provides certain senior executive officers defined benefits in relation to their compensation. Actuarially determined pension expense is charged to current operations using the projected unit credit method. All defined benefit plans are referred to as “the plans” throughout the remainder of this footnote. The following table sets forth the plans’ change in benefit obligation, plan assets and funded status, using a December 31 measurement date, and amounts recognized in the consolidated balance sheets at December 31 : Qualified Plans Non-qualified Plans Total 2017 2016 2017 2016 2017 2016 (In millions) Change in benefit obligation Projected benefit obligation, beginning of year $ 1,979 $ 1,895 $ 180 $ 167 $ 2,159 $ 2,062 Service cost 34 35 4 4 38 39 Interest cost 72 73 5 5 77 78 Actuarial (gains) losses 202 67 12 13 214 80 Benefit payments (150 ) (88 ) (7 ) (10 ) (157 ) (98 ) Administrative expenses (3 ) (3 ) — — (3 ) (3 ) Plan settlements — — (43 ) — (43 ) — Plan amendments — — — 1 — 1 Projected benefit obligation, end of year $ 2,134 $ 1,979 $ 151 $ 180 $ 2,285 $ 2,159 Change in plan assets Fair value of plan assets, beginning of year $ 1,990 $ 1,930 $ — $ — $ 1,990 $ 1,930 Actual return on plan assets 306 151 — — 306 151 Company contributions 75 — 50 10 125 10 Benefit payments (150 ) (88 ) (7 ) (10 ) (157 ) (98 ) Administrative expenses (3 ) (3 ) — — (3 ) (3 ) Plan settlements — — (43 ) — (43 ) — Fair value of plan assets, end of year $ 2,218 $ 1,990 $ — $ — $ 2,218 $ 1,990 Funded status and accrued benefit cost at measurement date $ 84 $ 11 $ (151 ) $ (180 ) $ (67 ) $ (169 ) Amount recognized in the Consolidated Balance Sheets: Other assets (liabilities) $ 84 $ 11 $ (151 ) $ (180 ) $ (67 ) $ (169 ) Pre-tax amounts recognized in Accumulated Other Comprehensive (Income) Loss: Net actuarial loss (gain) $ 644 $ 637 $ 48 $ 52 $ 692 $ 689 Prior service cost (credit) — — 1 1 1 1 $ 644 $ 637 $ 49 $ 53 $ 693 $ 690 The accumulated benefit obligation for the qualified plans was $2.0 billion and $1.8 billion as of December 31, 2017 and 2016 , respectively. Total plan assets exceeded the corresponding accumulated benefit obligation for the qualified plans as of both December 31, 2017 and 2016. The accumulated benefit obligation for the non-qualified plans was $143 million and $166 million as of December 31, 2017 and 2016 , respectively, which exceeded all corresponding plan assets for each period. Net periodic pension cost, which is recorded in salaries and employee benefits on the consolidated statements of income, included the following components for the years ended December 31 : Qualified Plans Non-qualified Plans Total 2017 2016 2015 2017 2016 2015 2017 2016 2015 (In millions) Service cost $ 34 $ 35 $ 40 $ 4 $ 4 $ 4 $ 38 $ 39 $ 44 Interest cost 72 73 84 5 5 6 77 78 90 Expected return on plan assets (143 ) (145 ) (152 ) — — — (143 ) (145 ) (152 ) Amortization of actuarial loss 32 31 43 4 3 4 36 34 47 Amortization of prior service cost — — — — — 1 — — 1 Settlement charge — — — 12 — 2 12 — 2 Net periodic pension (benefit) cost $ (5 ) $ (6 ) $ 15 $ 25 $ 12 $ 17 $ 20 $ 6 $ 32 The settlement charge relates to the settlement of liabilities under the SERP for certain plan participants. The estimated amounts that will be amortized from accumulated other comprehensive income (loss) into net periodic benefit cost in 2018 are as follows: Qualified Plans Non-qualified Plans (In millions) Actuarial loss $ 33 $ 4 $ 33 $ 4 The assumptions used to determine benefit obligations at December 31 are as follows: Qualified Plans Non-qualified Plans 2017 2016 2017 2016 Discount rate 3.71 % 4.32 % 3.50 % 3.93 % Rate of annual compensation increase 3.75 % 3.75 % 3.75 % 3.75 % The weighted-average assumptions used to determine net periodic benefit cost for the years ended December 31 are as follows: Qualified Plans Non-qualified Plans 2017 2016 2015 2017 2016 2015 Discount rate 4.34 % 4.56 % 4.20 % 3.93 % 4.19 % 3.75 % Expected long-term rate of return on plan assets 7.25 % 7.75 % 7.75 % N/A N/A N/A Rate of annual compensation increase 3.75 % 3.75 % 3.75 % 3.75 % 3.75 % 3.75 % Regions utilizes a disaggregated approach in the estimation of the service and interest components of net periodic pension costs by applying the specific spot rates along the yield curve used in the determination of the benefit obligation to the relevant projected cash flows. This provides a more precise measurement of service and interest costs by improving the correlation between projected benefit cash flows and the corresponding spot yield curve rates. The expected long-term rate of return on the qualified plans' assets is based on an estimated reasonable range of probable returns. The assumption is established by considering historical and anticipated return of the asset classes invested in by the qualified plans and the allocation strategy currently in place among those classes. Management chose a point within the range based on the probability of achievement combined with incremental returns attributable to active management. For 2018, the expected long-term rate of return on plan assets is 6.82 percent . The qualified pension plans' investment strategy is continuing to shift from focusing on maximizing asset returns to minimizing funding ratio volatility, with a planned increase in the allocation to bonds. The combined target asset allocation is 51 percent equities, 37 percent fixed income securities and 12 percent in all other types of investments. Equity securities include investments in large and small/mid cap companies primarily located in the U.S., international equities, and private equities. Fixed income securities include investments in corporate and government bonds, asset-backed securities and any other fixed income investments as allowed by respective prospectuses and other offering documents. Other types of investments may include hedge funds and real estate funds that follow several different strategies. The plans' assets are highly diversified with respect to asset class, security and manager. Investment risk is controlled with the plans' assets rebalancing to target allocations on a periodic basis and continual monitoring of investment managers’ performance relative to the investment guidelines established with each investment manager. Regions’ qualified pension plans have a portion of their investments in Regions' common stock. At December 31, 2017 , the plans held 2,855,618 shares, which represents a total market value of approximately $49 million , or approximately 2.2 percent of the plans' assets. The following table presents the fair value of Regions’ qualified pension plans’ financial assets as of December 31 : 2017 2016 Level 1 Level 2 Level 3 Fair Value Level 1 Level 2 Level 3 Fair Value (In millions) Cash and cash equivalents $ 48 $ — $ — $ 48 $ 52 $ — $ — $ 52 Fixed income securities: U.S. Treasury and federal agency securities $ — $ 172 $ — $ 172 $ — $ 144 $ — $ 144 Corporate bonds — 216 — 216 — 170 — 170 Total fixed income securities $ — $ 388 $ — $ 388 $ — $ 314 $ — $ 314 Equity securities: Domestic $ 427 $ — $ — $ 427 $ 303 $ — $ — $ 303 International 32 — — 32 21 — — 21 Total equity securities $ 459 $ — $ — $ 459 $ 324 $ — $ — $ 324 International mutual funds $ 100 $ — $ — $ 100 $ 192 192 $ — $ — $ 192 Total assets in the fair value hierarchy $ 607 $ 388 $ — $ 995 $ 568 $ 314 $ — $ 882 Collective trust funds: Fixed income fund (1) $ 388 $ 320 Common stock fund (1) 265 244 International fund (1) 216 182 Total collective trust funds $ 869 $ 746 Hedge funds measured at NAV (1) $ 46 $ 16 Real estate funds measured at NAV (1) $ 197 $ 239 Private equity funds measured at NAV (1) $ 111 $ 107 $ 2,218 $ 1,990 __________ (1) In accordance with accounting guidance adopted by Regions in 2016, investments that are measured at fair value using the net asset value per share (or its equivalent) practical expedient are no longer required to be classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of amounts reported in the fair value hierarchy to amounts reported on the balance sheet. See Note 1 for further discussion. For all investments, the plans attempt to use quoted market prices of identical assets on active exchanges, or Level 1 measurements. Where such quoted market prices are not available, the plans typically employ quoted market prices of similar instruments (including matrix pricing) and/or discounted cash flows to estimate a value of these securities, or Level 2 measurements. Level 2 discounted cash flow analyses are typically based on market interest rates, prepayment speeds and/or option adjusted spreads. Investments held in the plans consist of cash and cash equivalents, fixed income securities (U.S. Treasury, federal agency securities, mortgage-backed securities, collateralized mortgage obligations, obligations of states and political subdivisions and corporate bonds), equity securities (primarily common stock and mutual funds), collective trust funds, hedge funds, real estate funds, private equity and other assets and are recorded at fair value on a recurring basis. See Note 1 for a description of valuation methodologies related to U.S. Treasuries, federal agency securities, mortgage-backed securities, obligations of states and political subdivisions and equity securities. The methodology described in Note 1 for other debt securities is applicable to corporate bonds. Mutual funds are valued based on quoted market prices of identical assets on active exchanges; these valuations are Level 1 measurements. Collective trust funds, hedge funds, real estate funds, private equity funds and other assets are valued based on net asset value or the valuation of the limited partner’s portion of the equity of the fund. Third party fund managers provide these valuations based primarily on estimated valuations of underlying investments. Information about the expected cash flows for the qualified and non-qualified plans is as follows: Qualified Non-qualified (In millions) Expected Employer Contributions: 2018 $ — $ 10 Expected Benefit Payments: 2018 $ 93 $ 10 2019 95 11 2020 98 11 2021 102 22 2022 105 16 Next five years 573 56 OTHER PLANS Regions has a defined-contribution 401(k) plan that includes a Company match of eligible employee contributions. Eligible employees include those who have been employed for one year and have worked a minimum of 1,000 hours. Prior to 2015, the Company match was initially invested in Regions common stock. Effective January 1, 2015, the Company match is invested based on the employees' allocation elections. In 2017 , 2016 and 2015 , Regions provided an automatic 2 percent cash 401(k) contribution to eligible employees regardless of whether or not they were contributing to the 401(k) plan. To receive this contribution, employees must be employed at the end of the year and not actively accruing a benefit in the Regions’ pension plans. Regions’ cash contribution was approximately $18 million , $17 million and $15 million for 2017 , 2016 and 2015 , respectively. Eligible employees who are already contributing to the 401(k) plan will continue to receive up to a 4 percent Company match plus the automatic 2 percent cash contribution. Regions’ match to the 401(k) plan on behalf of employees totaled $48 million , $45 million and $40 million in 2017 , 2016 and 2015 , respectively. Regions’ 401(k) plan held 26 million shares and 29 million shares of Regions' common stock at December 31, 2017 and 2016 , respectively. The 401(k) plan received approximately $8 million , $9 million and $8 million in dividends on Regions' common stock for the years ended December 31, 2017 , 2016 and 2015 , respectively. Regions also sponsors defined benefit postretirement health care plans that cover certain retired employees. For these certain employees retiring before normal retirement age, the Company currently pays a portion of the costs of certain health care benefits until the retired employee becomes eligible for Medicare. Certain retirees, participating in plans of acquired entities, are offered a Medicare supplemental benefit. The plan is contributory and contains other cost-sharing features such as deductibles and co-payments. Retiree health care benefits, as well as similar benefits for active employees, are provided through a self-insured program in which Company and retiree costs are based on the amount of benefits paid. The Company’s policy is to fund the Company’s share of the cost of health care benefits in amounts determined at the discretion of management. Postretirement life insurance is also provided to a grandfathered group of employees and retirees. The assumed health care cost trend rate for postretirement medical benefits was 6.4 percent for 2017 and is assumed to decrease gradually to 4.5 percent by 2027 and remain at that level thereafter. A one-percentage point change in assumed health care cost trend rates would have an immaterial effect on total service cost and interest cost components as well as the related postretirement obligations. There was no material impact from other postretirement benefits on the consolidated statements of income for the years ended December 31, 2017 , 2016 and 2015 . The accumulated postretirement benefit obligation for these plans was $19 million and $20 million as of December 31, 2017 and 2016 , respectively.

Other Non-Interest Income and E

Other Non-Interest Income and Expense	12 Months Ended
	Dec. 31, 2017
Other Income and Expenses [Abstract]
Other Non-Interest Income and Expense	OTHER NON-INTEREST INCOME AND EXPENSE The following is a detail of other non-interest income from continuing operations for the years ended December 31 : 2017 2016 2015 (In millions) Capital markets fee income and other $ 161 $ 152 $ 104 Insurance commissions and fees 145 148 140 Bank-owned life insurance 81 95 74 Commercial credit fee income 71 73 76 Investment services fee income 60 58 55 Insurance proceeds — 50 91 Market value adjustments on employee benefit assets 16 3 (3 ) Other miscellaneous income 70 116 115 $ 604 $ 695 $ 652 The following is a detail of other non-interest expense from continuing operations for the years ended December 31 : 2017 2016 2015 (In millions) Outside services $ 172 $ 154 $ 149 FDIC insurance assessments 108 99 105 Professional, legal and regulatory expenses 95 89 137 Marketing 93 101 98 Credit/checkcard expenses 50 55 54 Branch consolidation, property and equipment charges 22 58 56 Visa class B shares expense 19 15 9 Provision (credit) for unfunded credit losses (16 ) 17 (13 ) Loss on early extinguishment of debt — 14 43 Other miscellaneous expenses 452 437 422 $ 995 $ 1,039 $ 1,060

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Taxes [Abstract]
Income Taxes	INCOME TAXES The components of income tax expense from continuing operations for the years ended December 31 were as follows: 2017 2016 2015 (In millions) Current income tax expense: Federal $ 376 $ 444 $ 293 State 30 21 7 Total current expense $ 406 $ 465 $ 300 Deferred income tax expense: Federal $ 172 $ 2 $ 115 State 36 47 40 Total deferred expense $ 208 $ 49 $ 155 Total income tax expense $ 614 $ 514 $ 455 __________ Note: The table above does not include total income tax expense (benefit) from discontinued operations of $2 million , $3 million , and $(9) million in 2017 , 2016 and 2015 , respectively. The deferred income tax expense reflected in discontinued operations was $1 million , $18 million and $46 million in 2017 , 2016 and 2015 , respectively. On December 22, 2017, Tax Reform was enacted. Effective January 1, 2018, Tax Reform reduces the maximum corporate statutory federal income tax rate from 35 percent to 21 percent . As a result of enactment, the Company recognized additional income tax expense of approximately $52 million in the fourth quarter of 2017, which included $25 million related to revaluation of its net deferred tax assets, $23 million related to the revision of its proportional amortization calculation associated with low-income housing investments, and $4 million related to revaluation of the reserve for unrecognized tax benefits. The revaluation included a $133 million decrease in the net deferred tax assets related to unrealized gains and losses included in stockholders' equity. The amounts discussed above related to Tax Reform represent estimates based upon the information available at December 31, 2017. As a result, the amounts could be adjusted during the measurement period, which will end in December 2018. Any such changes are not expected to be material to the Company's business, financial position, results of operations or cash flows. The Company adopted new accounting guidance effective December 31, 2017 that allows reclassification of the $133 million revaluation amount, which decreased accumulated other comprehensive income and increased retained earnings. Refer to Note 1 for additional information on the new accounting guidance. With the exception of the revaluation adjustment related to unrealized gains and losses included in stockholders' equity, income tax expense does not reflect the tax effects of unrealized losses on securities transferred to held to maturity, unrealized gains and losses on securities available for sale, unrealized gains and losses on derivative instruments and the net change from defined benefit pension plans and other postretirement benefits. Furthermore, following Tax Reform enactment, the income tax effects included in other comprehensive income were based on the newly enacted federal income tax rate including the effect of state income taxes. Refer to Note 15 for additional information on stockholders’ equity and accumulated other comprehensive income (loss). The Company accounts for investment tax credits using the deferral method. Investment tax credits generated totaled $102 million , $54 million and zero for 2017, 2016 and 2015, respectively. Income taxes from continuing operations for financial reporting purposes differs from the amount computed by applying the statutory federal income tax rate of 35 percent for the years ended December 31 , as shown in the following table: 2017 2016 2015 (Dollars in millions) Tax on income from continuing operations computed at statutory federal income tax rate $ 655 $ 585 $ 535 Increase (decrease) in taxes resulting from: State income tax, net of federal tax effect 43 44 30 Tax-exempt interest (54 ) (49 ) (44 ) Affordable housing investment amortization, net of tax benefits (excluding Tax Reform) (52 ) (50 ) (47 ) Impact of Tax Reform 52 — — Bank-owned life insurance (32 ) (37 ) (30 ) Lease financing 16 28 18 Other, net (14 ) (7 ) (7 ) Income tax expense $ 614 $ 514 $ 455 Effective tax rate 32.8 % 30.7 % 29.7 % ___ _______ Note: Income tax expense includes amortization of affordable housing investments of $160 million (including $23 million due to impact of Tax Reform), $117 million and $103 million for 2017, 2016 and 2015, respectively. Income tax expense for 2015 includes a benefit of $15 million related to an improved methodology implemented to estimate the effective state tax rate. Significant components of the Company’s net deferred tax asset at December 31 are listed below: 2017 2016 (In millions) Deferred tax assets: Unrealized gains and losses included in stockholders’ equity $ 253 $ 338 Allowance for loan losses 249 447 State net operating loss carryfowards, net of federal tax effect 82 88 Accrued expenses 55 92 Federal tax credit carryforwards 13 13 Fixed assets 4 — Employee benefits and deferred compensation — 37 Other 33 59 Total deferred tax assets 689 1,074 Less: valuation allowance (34 ) (30 ) Total deferred tax assets less valuation allowance 655 1,044 Deferred tax liabilities: Lease financing 292 424 Goodwill and intangibles 99 156 Mortgage servicing rights 63 93 Fixed assets — 15 Other 38 48 Total deferred tax liabilities 492 736 Net deferred tax asset $ 163 $ 308 The following table provides details of the Company’s tax carryforwards at December 31, 2017 , including the expiration dates, any related valuation allowance and the amount of taxable earnings necessary to fully realize each net deferred tax asset balance: Expiration Dates Deferred Tax Asset Balance Valuation Allowance Net Deferred Tax Asset Balance Pre-Tax Earnings Necessary to Realize (1) (In millions) Alternate minimum tax credits-federal None (2) $ 13 $ — $ 13 $ N/A Net operating losses-states 2018-2022 42 (9 ) 33 553 Net operating losses-states 2023-2029 33 (21 ) 12 240 Net operating losses-states 2030-2037 7 (4 ) 3 44 Other credits-states 2018-2022 — — — N/A Other credits-states 2023-2029 1 — 1 N/A ________ (1) N/A indicates that credits are not measured on a pre-tax basis. (2) Tax Reform repealed the AMT for tax years beginning after December 31, 2017 and provides a mechanism to utilize any AMT credit carryover through 2020 with any remaining credits being fully refundable in 2021. Of the $163 million net deferred tax asset, $62 million relates to net operating losses and tax credit carryforwards, $46 million of which expires before 2030 (as detailed in the table above). The remaining $101 million of net deferred tax assets do not have a set expiration date at December 31, 2017 . The Company’s determination of the realization of the net deferred tax asset is based on its assessment of all available positive and negative evidence. At December 31, 2017 , positive evidence supporting the realization of the deferred tax assets includes a history of positive earnings with no history of significant tax credit carryforwards expiring unused. In addition, the reversal of taxable temporary differences, excluding goodwill and the inclusion of the accretion of taxable temporary differences related to leveraged leases acquired in a previous business combination, will offset approximately $430 million of the gross deferred tax asset. The Company believes that a portion of the state net operating loss carryforwards and state tax credit carryforwards will not be realized due to the length of certain state carryforward periods. Accordingly, a valuation allowance has been established in the amount of $34 million against such benefits at December 31, 2017 compared to $30 million at December 31, 2016 . The valuation allowance increased during 2017 by $6 million as part of the $52 million increase to tax expense related to Tax Reform. The increase was partially offset by decreases related to certain state net operating losses and state tax credits. A reconciliation of the beginning and ending amount of unrecognized tax benefits (“UTBs”) is as follows: 2017 2016 2015 (In millions) Balance at beginning of year $ 31 $ 38 $ 50 Additions based on tax positions related to the current year — 3 2 Reductions based on tax positions taken in a prior period — (6 ) (8 ) Settlements — (3 ) (6 ) Expiration of statute of limitations (4 ) (1 ) — Balance at end of year $ 27 $ 31 $ 38 The Company files U.S. federal, state, and local income tax returns. The Company’s federal income tax returns are no longer subject to examination by the IRS for taxable years prior to 2013. In 2015, the Company entered the IRS’s Compliance Assurance Process program and is currently under examination for 2016, 2017 and 2018. The 2015 examination has been closed without adjustment. With few exceptions, the Company is no longer subject to state and local income tax examinations for tax years before 2010. Currently, there are disputed tax positions with certain states, including positions regarding investment and intellectual property subsidiaries. The Company continues to evaluate these positions and intends to defend proposed adjustments made by these tax authorities. The Company does not anticipate that the ultimate resolution of these examinations will result in a material change to its business, financial position, results of operations or cash flows. As a result of the potential resolution of certain federal and state income tax positions, it is reasonably possible that the UTBs could decrease as much as $24 million during the next twelve months, since resolved items will be removed from the balance whether their resolution results in payment or recognition in earnings. As of December 31, 2017 , 2016 and 2015 , the balance of the Company’s UTBs that would reduce the effective tax rate, if recognized, was $21 million , $20 million and $24 million , respectively. The remainder of the UTB balance has indirect tax benefits in other jurisdictions or is the tax effect of temporary differences. Income tax expense for 2017 , 2016 and 2015 , includes a total expense (benefit) of $(2) million , $1 million and $(1) million , respectively, for interest expense, interest income and penalties before the impact of any applicable federal and state deductions. As of December 31, 2017 and 2016 , the Company had a liability of $2 million and $4 million , respectively, for interest and penalties related to income taxes, before the impact of any applicable federal and state deductions.

Derivative Financial Instrument

Derivative Financial Instruments and Hedging Activities	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments and Hedging Activities	DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES The following tables present the notional amount and estimated fair value of derivative instruments on a gross basis as of December 31, 2017 and 2016 . The variation margin payments made during 2017 for derivatives cleared through the Chicago Mercantile Exchange are legally characterized as settlements of the derivatives. As a result, these positions are reflected as settled with no fair value presented for purposes of the balance sheet and related disclosures. 2017 2016 Notional Amount Estimated Fair Value Notional Amount Estimated Fair Value Gain (1) Loss (1) Gain (1) Loss (1) (In millions) Derivatives in fair value hedging relationships: Interest rate swaps $ 3,060 $ 1 $ 43 $ 2,257 $ 7 $ 40 Derivatives in cash flow hedging relationships: Interest rate swaps 6,825 5 188 9,000 19 269 Total derivatives designated as hedging instruments $ 9,885 $ 6 $ 231 $ 11,257 $ 26 $ 309 Derivatives not designated as hedging instruments: Interest rate swaps $ 40,841 $ 308 $ 342 $ 41,851 $ 412 $ 467 Interest rate options 4,598 23 15 3,877 24 12 Interest rate futures and forward commitments 20,404 6 5 18,605 11 6 Other contracts 5,721 51 48 5,813 106 93 Total derivatives not designated as hedging instruments $ 71,564 $ 388 $ 410 $ 70,146 $ 553 $ 578 Total derivatives $ 81,449 $ 394 $ 641 $ 81,403 $ 579 $ 887 _________ (1) Derivatives in a gain position are recorded as other assets and derivatives in a loss position are recorded as other liabilities on the consolidated balance sheets. HEDGING DERIVATIVES Derivatives entered into to manage interest rate risk and facilitate asset/liability management strategies are designated as hedging derivatives. Derivative financial instruments that qualify in a hedging relationship are classified, based on the exposure being hedged, as either fair value hedges or cash flow hedges. Additional information regarding accounting policies for derivatives is described in Note 1 "Summary of Significant Accounting Policies." FAIR VALUE HEDGES Fair value hedge relationships mitigate exposure to the change in fair value of an asset, liability or firm commitment. Regions enters into interest rate swap agreements to manage interest rate exposure on the Company’s fixed-rate borrowings, which includes long-term debt and certificates of deposit. These agreements involve the receipt of fixed-rate amounts in exchange for floating-rate interest payments over the life of the agreements. Regions enters into interest rate swap agreements to manage interest rate exposure on certain of the Company's fixed-rate available for sale debt securities. These agreements involve the payment of fixed-rate amounts in exchange for floating-rate interest receipts. CASH FLOW HEDGES Cash flow hedge relationships mitigate exposure to the variability of future cash flows or other forecasted transactions. Regions enters into interest rate swap agreements to manage overall cash flow changes related to interest rate risk exposure on LIBOR-based loans. The agreements effectively modify the Company’s exposure to interest rate risk by utilizing receive fixed/pay LIBOR interest rate swaps. Regions recognized an unrealized after-tax gain of $147 million and $166 million in accumulated other comprehensive income (loss) at December 31, 2017 and 2016 , respectively, related to terminated cash flow hedges of loan instruments which will be amortized into earnings in conjunction with the recognition of interest payments through 2025. Regions recognized pre-tax income of $68 million for both years ended December 31, 2017 and 2016 , respectively related to the amortization of discontinued cash flow hedges of loan instruments. Regions expects to reclassify out of accumulated other comprehensive income (loss) and into earnings approximately $30 million in pre-tax income due to the receipt or payment of interest payments on all cash flow hedges within the next twelve months. Included in this amount is $53 million in pre-tax net gains related to the amortization of discontinued cash flow hedges. The maximum length of time over which Regions is hedging its exposure to the variability in future cash flows for forecasted transactions is approximately eight years as of December 31, 2017 . The following tables present the effect of hedging derivative instruments on the consolidated statements of income for the years ended December 31 : Gain or (Loss) Recognized in Income on Derivatives Location of Amounts Recognized in Income on Derivatives and Related Hedged Item Gain or (Loss) Recognized in Income on Related Hedged Item 2017 2016 2015 2017 2016 2015 (In millions) (In millions) Fair Value Hedges: Interest rate swaps on: Debt/CDs $ 2 $ 12 $ 17 Interest expense $ (1 ) $ (3 ) $ 4 Debt/CDs (20 ) (33 ) (1 ) Other non-interest expense 22 32 1 Securities available for sale (4 ) (9 ) (14 ) Interest income — — — Securities available for sale 1 — (8 ) Other non-interest expense (2 ) (2 ) 6 Total $ (21 ) $ (30 ) $ (6 ) $ 19 $ 27 $ 11 Effective Portion (3) Gain or (Loss) Recognized in AOCI (1) Location of Amounts Reclassified from AOCI into Income Gain or (Loss) Reclassified from AOCI into Income (2) 2017 2016 2015 2017 2016 2015 (In millions) (In millions) Cash Flow Hedges: Interest rate swaps $ (51 ) $ (64 ) $ 42 Interest income on loans $ 86 $ 143 $ 153 Total $ (51 ) $ (64 ) $ 42 $ 86 $ 143 $ 153 ____ (1) After-tax (2) Pre-tax (3) All cash flow hedges were highly effective for all periods presented, and the change in fair value attributed to hedge ineffectiveness was not material. DERIVATIVES NOT DESIGNATED AS HEDGING INSTRUMENTS The Company holds a portfolio of interest rate swaps, option contracts, and futures and forward commitments that result from transactions with its commercial customers in which they manage their risks by entering into a derivative with Regions. The Company monitors and manages the net risk in this customer portfolio and enters into separate derivative contracts in order to reduce the overall exposure to pre-defined limits. For both derivatives with its end customers and derivatives Regions enters into to mitigate the risk in this portfolio, the Company is subject to market risk and the risk that the counterparty will default. The contracts in this portfolio are not designated as accounting hedges and are marked-to market through earnings (in capital markets fee income and other) and included in other assets and other liabilities, as appropriate. Regions enters into interest rate lock commitments, which are commitments to originate mortgage loans whereby the interest rate on the loan is determined prior to funding and the customers have locked into that interest rate. At December 31, 2017 and 2016 , Regions had $197 million and $274 million , respectively, in total notional amount of interest rate lock commitments. Regions manages market risk on interest rate lock commitments and mortgage loans held for sale with corresponding forward sale commitments. Residential mortgage loans held for sale are recorded at fair value with changes in fair value recorded in mortgage income. Commercial mortgage loans held for sale are recorded at the lower of cost or market or at fair value based on management's election. At December 31, 2017 and 2016 , Regions had $481 million and $786 million , respectively, in total notional amount related to these forward sale commitments. Changes in mark-to-market from both interest rate lock commitments and corresponding forward sale commitments related to residential mortgage loans are included in mortgage income. Changes in mark-to-market from both interest rate lock commitments and corresponding forward sale commitments related to commercial mortgage loans are included in capital markets fee income and other. Regions has elected to account for residential MSRs at fair market value with any changes to fair value being recorded within mortgage income. Concurrent with the election to use the fair value measurement method, Regions began using various derivative instruments, in the form of forward rate commitments, futures contracts, swaps and swaptions to mitigate the effect of changes in the fair value of its residential MSRs on its consolidated statements of income. As of December 31, 2017 and 2016 , the total notional amount related to these contracts was $4.8 billion and $7.2 billion , respectively. The following table presents the location and amount of gain or (loss) recognized in income on derivatives not designated as hedging instruments in the consolidated statements of income for the years ended December 31 : Derivatives Not Designated as Hedging Instruments 2017 2016 2015 (In millions) Capital markets fee income and other (1) : Interest rate swaps $ 11 $ 13 $ 14 Interest rate options 28 23 14 Interest rate futures and forward commitments 10 4 3 Other contracts (10 ) (3 ) 11 Total capital markets fee income and other 39 37 42 Mortgage income: Interest rate swaps 2 (2 ) 13 Interest rate options (7 ) (2 ) (1 ) Interest rate futures and forward commitments (3 ) 8 3 Total mortgage income (8 ) 4 15 $ 31 $ 41 $ 57 ______ (1) Capital markets fee income and other is included in Other income on the consolidated statements of income. Credit risk, defined as all positive exposures not collateralized with cash or other assets or reserved for, at December 31, 2017 and 2016 , totaled approximately $251 million and $334 million , respectively. This amount represents the net credit risk on all trading and other derivative positions held by Regions. CREDIT DERIVATIVES Regions has both bought and sold credit protection in the form of participations on interest rate swaps (swap participations). These swap participations, which meet the definition of credit derivatives, were entered into in the ordinary course of business to serve the credit needs of customers. Swap participations, whereby Regions has purchased credit protection, entitle Regions to receive a payment from the counterparty if the customer fails to make payment on any amounts due to Regions upon early termination of the swap transaction and have maturities between 2018 and 2024. Credit derivatives whereby Regions has sold credit protection have maturities between 2018 and 2025. For contracts where Regions sold credit protection, Regions would be required to make payment to the counterparty if the customer fails to make payment on any amounts due to the counterparty upon early termination of the swap transaction. Regions bases the current status of the prepayment/performance risk on bought and sold credit derivatives on recently issued internal risk ratings consistent with the risk management practices of unfunded commitments. Regions’ maximum potential amount of future payments under these contracts as of December 31, 2017 was approximately $356 million . This scenario would only occur if variable interest rates were at zero percent and all counterparties defaulted with zero recovery. The fair value of sold protection at December 31, 2017 and 2016 was immaterial. In transactions where Regions has sold credit protection, recourse to collateral associated with the original swap transaction is available to offset some or all of Regions’ obligation. Regions has bought credit protection in the form of credit default indices. These indices, which meet the definition of credit derivatives, were entered into in the ordinary course of business to economically hedge credit spread risk in commercial mortgage loans held for sale whereby the fair value option has been elected. Credit derivatives, whereby Regions has purchased credit protection, entitle Regions to receive a payment from the counterparty if losses on the underlying index exceed a certain threshold, dependent upon the tranche rating of the capital structure. CONTINGENT FEATURES Certain of Regions’ derivative instrument contracts with broker-dealers contain credit-related termination provisions and/or credit related provisions regarding the posting of collateral, allowing those broker-dealers to terminate the contracts in the event that Regions’ and/or Regions Bank’s credit ratings fall below specified ratings from certain major credit rating agencies. The aggregate fair value of all derivative instruments with any credit-risk-related contingent features that were in a liability position on December 31, 2017 and 2016 , was $91 million and $141 million , respectively, for which Regions had posted collateral of $90 million and $141 million , respectively, in the normal course of business. OFFSETTING Regions engages in derivatives transactions with dealers and customers. These derivatives transactions are subject to enforceable master netting agreements, which include a right of setoff by the non-defaulting or non-affected party upon early termination of the derivatives transaction. The following table presents the Company's gross derivative positions, including collateral posted or received, as of December 31, 2017 and 2016 . Offsetting Derivative Assets Offsetting Derivative Liabilities 2017 2016 2017 2016 (In millions) Gross amounts subject to offsetting $ 231 $ 414 $ 342 $ 583 Gross amounts not subject to offsetting 163 165 299 304 Gross amounts recognized 394 579 641 887 Gross amounts offset in the consolidated balance sheets (1) 141 241 238 541 Net amounts presented in the consolidated balance sheets 253 338 403 346 Gross amounts not offset in the consolidated balance sheets: Financial instruments 2 4 50 50 Cash collateral received/posted — — 257 227 Net amounts $ 251 $ 334 $ 96 $ 69 _________ (1) At December 31, 2017 , gross amounts of derivative assets and liabilities offset in the consolidated balance sheets presented above include cash collateral received of $34 million and cash collateral posted of $131 million . At December 31, 2016 , the gross amounts of derivative assets and liabilities offset in the consolidated balance sheets presented above include cash collateral received of $48 million and cash collateral posted of $349 million . Gross amounts of derivatives not subject to offsetting primarily consist of derivatives cleared through a Central Clearing House and interest rate lock commitments to originate mortgage loans. Effective January 16, 2018, the variation margin payments made for derivatives cleared through LCH are legally characterized as settlements of the derivatives. As a result, during 2018 these positions will be reflected as settled with no fair value presented in the balance sheet and related disclosures. The related fair value amounts as of December 31, 2017 were approximately $158 million of assets and $298 million of liabilities. Furthermore, variation margin payments of approximately $140 million , which are recorded as assets on the balance sheet at December 31, 2017, will also be reflected as settled in 2018.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	FAIR VALUE MEASUREMENTS See Note 1 for a description of valuation methodologies for assets and liabilities measured at fair value on a recurring and non-recurring basis. Assets and liabilities measured at fair value rarely transfer between Level 1 and Level 2 measurements. There were no such transfers during the years ended December 31, 2017 , 2016 , or 2015 . Trading account securities and securities available for sale may be periodically transferred to or from Level 3 valuation based on management’s conclusion regarding the observability of inputs used in valuing the securities. Such transfers are accounted for as if they occur at the beginning of a reporting period.The following table presents assets and liabilities measured at estimated fair value on a recurring basis and non-recurring basis as of December 31: 2017 2016 Level 1 Level 2 Level 3 (1) Total Estimated Fair Value Level 1 Level 2 Level 3 (1) Total Estimated Fair Value (In millions) Recurring fair value measurements Trading account securities $ 189 $ — $ — $ 189 $ 124 $ — $ — $ 124 Securities available for sale: U.S. Treasury securities $ 331 $ — $ — $ 331 $ 303 $ — $ — $ 303 Federal agency securities — 28 — 28 — 35 — 35 Obligations of states and political subdivisions — — — — — 1 — 1 Mortgage-backed securities: Residential agency — 17,431 — 17,431 — 17,371 — 17,371 Residential non-agency — — 3 3 — — 4 4 Commercial agency — 3,714 — 3,714 — 3,463 — 3,463 Commercial non-agency — 788 — 788 — 1,129 — 1,129 Corporate and other debt securities — 1,105 3 1,108 — 1,271 3 1,274 Equity securities 225 — — 225 201 — — 201 Total securities available for sale $ 556 $ 23,066 $ 6 $ 23,628 $ 504 $ 23,270 $ 7 $ 23,781 Mortgage loans held for sale $ — $ 325 $ — $ 325 $ — $ 414 $ 33 $ 447 Residential mortgage servicing rights $ — $ — $ 336 $ 336 $ — $ — $ 324 $ 324 Derivative assets: Interest rate swaps $ — $ 314 $ — $ 314 $ — $ 438 $ — $ 438 Interest rate options — 18 5 23 — 13 11 24 Interest rate futures and forward commitments — 6 — 6 — 11 — 11 Other contracts 2 49 — 51 2 104 — 106 Total derivative assets $ 2 $ 387 $ 5 $ 394 $ 2 $ 566 $ 11 $ 579 Derivative liabilities: Interest rate swaps $ — $ 573 $ — $ 573 $ — $ 776 $ — $ 776 Interest rate options — 15 — 15 — 12 — 12 Interest rate futures and forward commitments — 5 — 5 — 6 — 6 Other contracts 2 46 — 48 1 92 — 93 Total derivative liabilities $ 2 $ 639 $ — $ 641 $ 1 $ 886 $ — $ 887 Non-recurring fair value measurements Loans held for sale $ — $ — $ 20 $ 20 $ — $ — $ 7 $ 7 Foreclosed property and other real estate — 24 9 33 — 29 6 35 _________ (1) All following disclosures related to Level 3 recurring and non-recurring assets do not include those deemed to be immaterial. Assets and liabilities in all levels could result in volatile and material price fluctuations. Realized and unrealized gains and losses on Level 3 assets represent only a portion of the risk to market fluctuations in Regions’ consolidated balance sheets. Further, derivatives included in Levels 2 and 3 are used by ALCO in a holistic approach to managing price fluctuation risks. The following tables illustrate rollforwards for all material assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the years ended December 31, 2017 , 2016 and 2015 , respectively. Year Ended December 31, 2017 Total Realized / Unrealized Gains or Losses Opening Balance January 1, 2017 Included in Earnings Included in Other Compre- hensive Income (Loss) Purchases Sales Issuances Settlements Transfers into Level 3 Transfers out of Level 3 Closing Balance December 31, 2017 (In millions) Level 3 Instruments Only Residential mortgage servicing rights $ 324 (52 ) (1) — 64 — — — — — $ 336 Year Ended December 31, 2016 Opening Balance January 1, 2016 Total Realized / Unrealized Gains or Losses Purchases Sales Issuances Settlements Transfers into Level 3 Transfers out of Level 3 Closing Included in Earnings Included in Other Compre- hensive Income (Loss) (In millions) Level 3 Instruments Only Residential mortgage servicing rights $ 252 (36 ) (1) — 108 — — — — — $ 324 Year Ended December 31, 2015 Opening Balance January 1, 2015 Total Realized / Unrealized Gains or Losses Purchases Sales Issuances Settlements Transfers into Level 3 Transfers out of Level 3 Closing Balance December 31, 2015 Included in Earnings Included in Other Compre- hensive Income (Loss) (In millions) Level 3 Instruments Only Residential mortgage servicing rights $ 257 (41 ) (1) — 36 — — — — — $ 252 _________ (1) Included in mortgage income. The following table presents the fair value adjustments related to non-recurring fair value measurements for the years ended December 31: 2017 2016 (In millions) Loans held for sale $ (22 ) $ (26 ) Foreclosed property and other real estate (31 ) (42 ) The following tables present detailed information regarding material assets and liabilities measured at fair value using significant unobservable inputs (Level 3) as of December 31, 2017 , 2016 and 2015 . The tables include the valuation techniques and the significant unobservable inputs utilized. The range of each significant unobservable input as well as the weighted-average within the range utilized at December 31, 2017 , 2016 and 2015 are included. Following the tables are a description of the valuation techniques and the sensitivity of the techniques to changes in the significant unobservable inputs. December 31, 2017 Level 3 Estimated Fair Value at December 31, 2017 Valuation Technique Unobservable Input(s) Quantitative Range of Unobservable Inputs and (Weighted-Average) (Dollars in millions) Recurring fair value measurements: Residential mortgage servicing rights (1) $336 Discounted cash flow Weighted-average CPR (%) 7.9% - 28.1% (9.9%) OAS (%) 8.1% - 15.0% (8.6%) December 31, 2016 Level 3 Valuation Technique Unobservable Input(s) Quantitative Range of Unobservable Inputs and (Weighted-Average) (Dollars in millions) Recurring fair value measurements: Residential mortgage servicing rights (1) $324 Discounted cash flow Weighted-average CPR (%) 5.7% - 24.3% (7.6%) OAS (%) 8.2% - 13.6% (10.5%) December 31, 2015 Level 3 Valuation Unobservable Quantitative Range of (Dollars in millions) Recurring fair value measurements: Residential mortgage servicing rights (1) $252 Discounted cash flow Weighted-average CPR (%) 10.5% - 11.5% (10.9%) OAS (%) 8.7% - 13.3% (10.0%) _________ (1) See Note 7 for additional disclosures related to assumptions used in the fair value calculation for residential MSRs. RECURRING FAIR VALUE MEASUREMENTS USING SIGNIFICANT UNOBSERVABLE INPUTS Residential mortgage servicing rights The significant unobservable inputs used in the fair value measurement of residential MSRs are OAS and CPR. This valuation requires generating cash flow projections over multiple interest rate scenarios and discounting those cash flows at a risk adjusted rate. Additionally, the impact of prepayments and changes in the OAS are based on a variety of underlying inputs including servicing costs. Increases or decreases to the underlying cash flow inputs will have a corresponding impact on the value of the MSR asset. The net change in unrealized gains (losses) included in earnings related to MSRs held at period end are disclosed as the changes in valuation inputs or assumptions included in the MSR rollforward table in Note 7. See Note 7 for these amounts and additional disclosures related to assumptions used in the fair value calculation for MSRs. FAIR VALUE OPTION Regions has elected the fair value option for all FNMA and FHLMC eligible residential mortgage loans and certain commercial mortgage loans originated with the intent to sell. These elections allow for a more effective offset of the changes in fair values of the loans and the derivative instruments used to economically hedge them without the burden of complying with the requirements for hedge accounting. Regions has not elected the fair value option for other loans held for sale primarily because they are not economically hedged using derivative instruments. Fair values of residential mortgage loans held for sale are based on traded market prices of similar assets where available and/or discounted cash flows at market interest rates, adjusted for securitization activities that include servicing values and market conditions, and are recorded in loans held for sale in the consolidated balance sheets. Fair values of commercial mortgage loans held for sale are based on traded market prices for comparable commercial mortgage-backed securitizations, into which the loans will be placed, adjusted for movements of interest rates and credit spreads. The following table summarizes the difference between the aggregate fair value and the aggregate unpaid principal balance for mortgage loans held for sale measured at fair value at December 31 : 2017 2016 Aggregate Fair Value Aggregate Unpaid Principal Aggregate Fair Value Less Aggregate Unpaid Principal Aggregate Fair Value Aggregate Unpaid Principal Aggregate Fair Value Less Aggregate Unpaid Principal (In millions) Mortgage loans held for sale, at fair value $ 325 $ 314 $ 11 $ 447 $ 443 $ 4 Interest income on mortgage loans held for sale is recognized based on contractual rates and is reflected in interest income on loans held for sale in the consolidated statements of income. The following table details net gains and losses resulting from changes in fair value of these loans, which were recorded in mortgage and capital markets income in the consolidated statements of income for the years presented. These changes in fair value are mostly offset by economic hedging activities. An immaterial portion of these amounts was attributable to changes in instrument-specific credit risk. 2017 2016 (In millions) Net gains (losses) resulting from changes in fair value $ 5 $ (8 ) The carrying amounts and estimated fair values, as well as the level within the fair value hierarchy, of the Company’s financial instruments as of December 31, 2017 are as follows: 2017 Carrying Amount Estimated Fair Value (1) Level 1 Level 2 Level 3 (In millions) Financial assets: Cash and cash equivalents $ 3,981 $ 3,981 $ 3,981 $ — $ — Trading account securities 189 189 189 — — Securities held to maturity 1,658 1,667 — 1,667 — Securities available for sale 23,628 23,628 556 23,066 6 Loans held for sale 348 348 — 328 20 Loans (excluding leases), net of unearned income and allowance for loan losses (2)(3) 77,942 76,871 — — 76,871 Other earning assets (4) 988 988 — 988 — Derivative assets 394 394 2 387 5 Financial liabilities: Derivative liabilities 641 641 2 639 — Deposits 96,889 96,927 — 96,927 — Short-term borrowings 500 500 — 500 — Long-term borrowings 8,132 8,517 — 7,757 760 Loan commitments and letters of credit 79 540 — — 540 _________ (1) Estimated fair values are consistent with an exit price concept. The assumptions used to estimate the fair values are intended to approximate those that a market participant would use in a hypothetical orderly transaction. In estimating fair value, the Company maintains a corporate governance program to make adjustments for estimated changes in interest rates, market liquidity and credit spreads in the periods they are deemed to have occurred. Historically, the Company has utilized the results of a third-party vendor model to support its primary valuation approach for loans. For the year ended 2017, the Company implemented an internally-supported loan valuation model as its primary valuation approach for loans, including unfunded loan commitments and letters of credit. (2) The estimated fair value of portfolio loans assumes sale of the loans to a third-party financial investor. Accordingly, the value to the Company if the loans were held to maturity is not reflected in the fair value estimate. In the current whole loan market, financial investors are generally requiring a higher rate of return than the return inherent in loans if held to maturity. The fair value discount on the loan portfolio's net carrying amount at December 31, 2017 was $1.1 billion or 1.4 percent. (3) Excluded from this table is the capital lease carrying amount of $1.1 billion at December 31, 2017 . (4) Excluded from this table is the operating lease carrying amount of $489 million at December 31, 2017 . The carrying amounts and estimated fair values, as well as the level within the fair value hierarchy, of the Company's financial instruments as of December 31, 2016 are as follows: 2016 Carrying Amount Estimated Fair Value (1) Level 1 Level 2 Level 3 (In millions) Financial assets: Cash and cash equivalents $ 5,451 $ 5,451 $ 5,451 $ — $ — Trading account securities 124 124 124 — — Securities held to maturity 1,362 1,369 — 1,369 — Securities available for sale 23,781 23,781 504 23,270 7 Loans held for sale 718 722 — 689 33 Loans (excluding leases), net of unearned income and allowance for loan losses (2)(3) 78,128 74,063 — — 74,063 Other earning assets (4) 956 956 — 956 — Derivative assets 579 579 2 566 11 Financial liabilities: Derivative liabilities 887 887 1 886 — Deposits 99,035 99,081 — 99,081 — Short-term borrowings — — — — — Long-term borrowings 7,763 8,008 — 5,408 2,600 Loan commitments and letters of credit 102 484 — — 484 _________ (1) Estimated fair values are consistent with an exit price concept. The assumptions used to estimate the fair values are intended to approximate those that a market participant would use in a hypothetical orderly transaction. In estimating fair value, the Company maintains a corporate governance program to make adjustments for estimated changes in interest rates, market liquidity and credit spreads in the periods they are deemed to have occurred. Historically, the Company has utilized the results of a third-party vendor model to support its primary valuation approach for loans. (2) The estimated fair value of portfolio loans assumes sale of the loans to a third-party financial investor. Accordingly, the value to the Company if the loans were held to maturity is not reflected in the fair value estimate. In the current whole loan market, financial investors are generally requiring a higher rate of return than the return inherent in loans if held to maturity. The fair value discount on the loan portfolio's net carrying amount at December 31, 2016 was $4.1 billion or 5.2 percent. (3) Excluded from this table is the capital lease carrying amount of $876 million at December 31, 2016 . (4) Excluded from this table is the operating lease carrying amount of $688 million at December 31, 2016 .

Business Segment Information

Business Segment Information	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Business Segment Information	BUSINESS SEGMENT INFORMATION Each of Regions’ reportable segments is a strategic business unit that serves specific needs of Regions’ customers based on the products and services provided. The segments are based on the manner in which management views the financial performance of the business. The Company has three reportable segments: Corporate Bank, Consumer Bank, and Wealth Management, with the remainder split between Discontinued Operations and Other. The application and development of management reporting methodologies is a dynamic process and is subject to periodic enhancements. As these enhancements are made, financial results presented by each reportable segment may be periodically revised. The Corporate Bank segment represents the Company’s commercial banking functions including commercial and industrial, commercial real estate and investor real estate lending. This segment also includes equipment lease financing. Corporate Bank customers include corporate, middle market, and commercial real estate developers and investors. Corresponding deposit products related to these types of customers are also included in this segment. The Consumer Bank segment represents the Company’s branch network, including consumer banking products and services related to residential first mortgages, home equity lines and loans, branch small business loans, indirect loans, consumer credit cards and other consumer loans, as well as the corresponding deposit relationships. These services are also provided through alternative channels such as the internet and telephone banking. The Wealth Management segment offers individuals, businesses, governmental institutions and non-profit entities a wide range of solutions to help protect, grow and transfer wealth. Offerings include credit related products, trust and investment management, asset management, retirement and savings solutions, estate planning and personal and commercial insurance products. Discontinued Operations includes all brokerage and investment activities associated with Morgan Keegan. As discussed in Note 3, Regions closed the sale of Morgan Keegan and related entities on April 2, 2012. Other includes the Company’s Treasury function, the securities portfolio, wholesale funding activities, interest rate risk management activities and other corporate functions that are not related to a strategic business unit. Also within Other are certain reconciling items in order to translate the segment results that are based on management accounting practices into consolidated results. Management accounting practices utilized by Regions as the basis of presentation for segment results include the following: • Net interest income and other financing income is presented based upon an FTP approach, for which market-based funding charges/credits are assigned within the segments. By allocating a cost or a credit to each product based on the FTP framework, management is able to more effectively measure the net interest margin contribution of its assets/liabilities by segment. The summation of the interest income/expense and FTP charges/credits for each segment is its designated net interest income and other financing income. The variance between the Company’s cumulative FTP charges and cumulative FTP credits is offset in Other. • Provision for loan losses is allocated to each segment based on an estimated loss methodology. The difference between the consolidated provision for loan losses and the segments’ estimated loss is reflected in Other. • Income tax expense (benefit) is calculated for the Corporate Bank, Consumer Bank and Wealth Management based on a consistent federal and state statutory rate. Discontinued Operations reflects the actual income tax expense (benefit) of its results. Any difference between the Company’s consolidated income tax expense (benefit) and the segments’ calculated amounts is reflected in Other. • Management reporting allocations of certain expenses are made in order to analyze the financial performance of the segments. These allocations consist of operational and overhead cost pools and are intended to represent the total costs to support a segment. The following tables present financial information for each reportable segment for the year ended December 31 : 2017 Corporate Bank Consumer Bank Wealth Management Other Continuing Operations Discontinued Operations Consolidated (In millions) Net interest income and other financing income (loss) $ 1,422 $ 2,140 $ 192 $ (214 ) $ 3,540 $ — $ 3,540 Provision (credit) for loan losses 258 297 20 (425 ) 150 — 150 Non-interest income 467 1,116 450 72 2,105 — 2,105 Non-interest expense 865 2,051 481 227 3,624 (8 ) 3,616 Income (loss) before income taxes 766 908 141 56 1,871 8 1,879 Income tax expense (benefit) 291 345 53 (75 ) 614 2 616 Net income (loss) $ 475 $ 563 $ 88 $ 131 $ 1,257 $ 6 $ 1,263 Average assets $ 51,680 $ 34,997 $ 3,117 $ 34,182 $ 123,976 $ — $ 123,976 2016 Corporate Bank Consumer Bank Wealth Management Other Continuing Operations Discontinued Operations Consolidated (In millions) Net interest income and other financing income (loss) $ 1,449 $ 2,047 $ 175 $ (273 ) $ 3,398 $ — $ 3,398 Provision (credit) for loan losses 286 290 22 (336 ) 262 — 262 Non-interest income 485 1,126 427 115 2,153 — 2,153 Non-interest expense 876 2,061 469 211 3,617 (8 ) 3,609 Income (loss) before income taxes 772 822 111 (33 ) 1,672 8 1,680 Income tax expense (benefit) 293 312 42 (133 ) 514 3 517 Net income (loss) $ 479 $ 510 $ 69 $ 100 $ 1,158 $ 5 $ 1,163 Average assets $ 54,006 $ 34,597 $ 3,232 $ 33,671 $ 125,506 $ — $ 125,506 2015 Corporate Bank Consumer Bank Wealth Management Other Continuing Operations Discontinued Operations Consolidated (In millions) Net interest income and other financing income (loss) $ 1,512 $ 2,018 $ 167 $ (390 ) $ 3,307 $ — $ 3,307 Provision (credit) for loan losses 301 276 22 (358 ) 241 — 241 Non-interest income 435 1,074 408 154 2,071 — 2,071 Non-interest expense 887 2,067 458 195 3,607 22 3,629 Income (loss) before income taxes 759 749 95 (73 ) 1,530 (22 ) 1,508 Income tax expense (benefit) 288 285 37 (155 ) 455 (9 ) 446 Net income (loss) $ 471 $ 464 $ 58 $ 82 $ 1,075 $ (13 ) $ 1,062 Average assets $ 53,308 $ 33,415 $ 3,185 $ 32,357 $ 122,265 $ — $ 122,265

Commitments, Contingencies and

Commitments, Contingencies and Guarantees	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitment, Contingencies and Guarantees	COMMITMENTS, CONTINGENCIES AND GUARANTEES COMMERCIAL COMMITMENTS Regions issues off-balance sheet financial instruments in connection with lending activities. The credit risk associated with these instruments is essentially the same as that involved in extending loans to customers and is subject to Regions’ normal credit approval policies and procedures. Regions measures inherent risk associated with these instruments by recording a reserve for unfunded commitments based on an assessment of the likelihood that the guarantee will be funded and the creditworthiness of the customer or counterparty. Collateral is obtained based on management’s assessment of the creditworthiness of the customer. Credit risk associated with these instruments as of December 31 is represented by the contractual amounts indicated in the following table: 2017 2016 (In millions) Unused commitments to extend credit $ 45,705 $ 44,408 Standby letters of credit 1,348 1,425 Commercial letters of credit 76 46 Liabilities associated with standby letters of credit 26 34 Assets associated with standby letters of credit 28 34 Reserve for unfunded credit commitments 53 69 Unused commitments to extend credit —To accommodate the financial needs of its customers, Regions makes commitments under various terms to lend funds to consumers, businesses and other entities. These commitments include (among others) credit card and other revolving credit agreements, term loan commitments and short-term borrowing agreements. Many of these loan commitments have fixed expiration dates or other termination clauses and may require payment of a fee. Since many of these commitments are expected to expire without being funded, the total commitment amounts do not necessarily represent future liquidity requirements. Standby letters of credit —Standby letters of credit are also issued to customers which commit Regions to make payments on behalf of customers if certain specified future events occur. Regions has recourse against the customer for any amount required to be paid to a third party under a standby letter of credit. Historically, a large percentage of standby letters of credit expired without being funded. The contractual amount of standby letters of credit represents the maximum potential amount of future payments Regions could be required to make and represents Regions’ maximum credit risk. Commercial letters of credit —Commercial letters of credit are issued to facilitate foreign or domestic trade transactions for customers. As a general rule, drafts will be drawn when the goods underlying the transaction are in transit. LEASE COMMITMENTS Regions and its subsidiaries lease land, premises and equipment under cancelable and non-cancelable leases, some of which contain renewal options under various terms. The leased properties are used primarily for banking purposes. Total rental expense on operating leases for the years ended December 31, 2017 , 2016 and 2015 was $167 million , $172 million and $174 million , respectively. The approximate future minimum rental commitments as of December 31, 2017 , for all non-cancelable leases with initial or remaining terms of one year or more are shown in the following table. Included in these amounts are all renewal options reasonably assured of being exercised. Premises Equipment Total (In millions) 2018 $ 104 $ 31 $ 135 2019 101 13 114 2020 90 5 95 2021 76 — 76 2022 65 — 65 Thereafter 252 — 252 $ 688 $ 49 $ 737 LEGAL CONTINGENCIES Regions and its subsidiaries are subject to loss contingencies related to litigation, claims, investigations and legal and administrative cases and proceedings arising in the ordinary course of business. Regions evaluates these contingencies based on information currently available, including advice of counsel. Regions establishes accruals for those matters when a loss contingency is considered probable and the related amount is reasonably estimable. Any accruals are periodically reviewed and may be adjusted as circumstances change. Some of Regions' exposure with respect to loss contingencies may be offset by applicable insurance coverage. In determining the amounts of any accruals or estimates of possible loss contingencies however, Regions does not take into account the availability of insurance coverage. To the extent that Regions has an insurance recovery, the proceeds are recorded in the period the recovery is received. In addition, Regions has agreed to indemnify Raymond James for all legal matters resulting from pre-closing activities in conjunction with the sale of Morgan Keegan and recorded an indemnification obligation at fair value in the second quarter of 2012. When it is practicable, Regions estimates possible loss contingencies, whether or not there is an accrued probable loss. When Regions is able to estimate such possible losses, and when it is reasonably possible Regions could incur losses in excess of amounts accrued, Regions discloses the aggregate estimation of such possible losses. Regions currently estimates that any such losses in excess of amounts accrued, including legal contingencies that are subject to the indemnification agreement with Raymond James, would be immaterial to Regions' financial statements as a whole. However, as available information changes, the matters for which Regions is able to estimate, as well as the estimates themselves will be adjusted accordingly. Assessments of litigation and claims exposure are difficult because they involve inherently unpredictable factors including, but not limited to, the following: whether the proceeding is in the early stages; whether damages are unspecified, unsupported, or uncertain; whether there is a potential for punitive or other pecuniary damages; whether the matter involves legal uncertainties, including novel issues of law; whether the matter involves multiple parties and/or jurisdictions; whether discovery has begun or is not complete; whether meaningful settlement discussions have commenced; and whether the lawsuit involves class allegations. Assessments of class action litigation, which is generally more complex than other types of litigation, are particularly difficult, especially in the early stages of the proceeding when it is not known whether a class will be certified or how a potential class, if certified, will be defined. As a result, Regions may be unable to estimate reasonably possible losses with respect to some of the matters disclosed below, and the aggregated estimated amount discussed above may not include an estimate for every matter disclosed below. In July 2006, Morgan Keegan and a former Morgan Keegan analyst were named as defendants in a lawsuit filed by a Canadian insurance and financial services company and its American subsidiary in the Circuit Court of Morris County, New Jersey. Plaintiffs alleged civil claims under the RICO Act and claims for commercial disparagement, tortious interference with contractual relationships, tortious interference with prospective economic advantage and common law conspiracy. Plaintiffs allege that defendants engaged in a multi-year conspiracy to publish and disseminate false and defamatory information about plaintiffs to improperly drive down plaintiffs’ stock price, so that others could profit from short positions. Plaintiffs allege that defendants’ actions damaged their reputations and harmed their business relationships. Plaintiffs seek monetary damages for a number of categories of alleged damages, including lost insurance business, lost financings and increased financing costs, increased audit fees and directors and officers insurance premiums and lost acquisitions. In September 2012, the trial court dismissed the case with prejudice. Plaintiffs filed an appeal, and in April 2017, the appellate court affirmed the dismissal of the plaintiffs’ claims under the RICO Act. The appellate court reversed the trial court’s dismissal of the commercial disparagement and tortious interference claims and remanded those claims but limited the plaintiffs’ damages. Plaintiffs filed an appeal with the Supreme Court of New Jersey in May 2017, and in October 2017, that court denied the plaintiffs' petition. This matter is subject to the indemnification agreement with Raymond James. Regions is involved in formal and informal information-gathering requests, investigations, reviews, examinations and proceedings by various governmental regulatory agencies, law enforcement authorities and self-regulatory bodies regarding Regions’ business, Regions' business practices and policies, and the conduct of persons with whom Regions does business. Additional inquiries will arise from time to time. In connection with those inquiries, Regions receives document requests, subpoenas and other requests for information. The inquiries, including the one described below, could develop into administrative, civil or criminal proceedings or enforcement actions that could result in consequences that have a material effect on Regions' consolidated financial position, results of operations or cash flows as a whole. Such consequences could include adverse judgments, findings, settlements, penalties, fines, orders, injunctions, restitution, or alterations in our business practices, and could result in additional expenses and collateral costs, including reputational damage. Regions is cooperating with an investigation by the United States Attorney’s Office for the Eastern District of New York pertaining to Regions' banking relationship with a former customer and accounts maintained by related entities and individuals affiliated with the customer who may be involved in criminal activity, as well as related aspects of Regions' Anti-Money Laundering and Bank Secrecy Act compliance program. While the final outcome of litigation and claims exposures or of any inquiries is inherently unpredictable, management is currently of the opinion that the outcome of pending and threatened litigation and inquiries will not have a material effect on Regions’ business, consolidated financial position, results of operations or cash flows as a whole. However, in the event of unexpected future developments, it is reasonably possible that an adverse outcome in any of the matters discussed above could be material to Regions’ business, consolidated financial position, results of operations or cash flows for any particular reporting period of occurrence. GUARANTEES INDEMNIFICATION OBLIGATION As discussed in Note 2, on April 2, 2012 (“Closing Date”), Regions closed the sale of Morgan Keegan and related affiliates to Raymond James. In connection with the sale, Regions agreed to indemnify Raymond James for all legal matters related to pre-closing activities, including matters filed subsequent to the Closing Date that relate to actions that occurred prior to closing. Losses under the indemnification include legal and other expenses, such as costs for judgments, settlements and awards associated with the defense and resolution of the indemnified matters. The maximum potential amount of future payments that Regions could be required to make under the indemnification is indeterminable due to the indefinite term of some of the obligations. As of December 31, 2017 , the carrying value and fair value of the indemnification obligation were immaterial. FANNIE MAE DUS LOSS SHARE GUARANTEE Regions is a DUS lender. The DUS program provides liquidity to the multi-family housing market. Regions services loans sold to Fannie Mae and is required to provide a loss share guarantee equal to one-third of the majority of its DUS servicing portfolio. At December 31, 2017 and 2016, the Company's DUS servicing portfolio totaled approximately $2.9 billion and $1.8 billion , respectively. Regions' maximum quantifiable contingent liability related to its loss share guarantee was approximately $923 million and $559 million at December 31, 2017 and 2016, respectively.The Company would be liable for this amount only if all of the loans it services for Fannie Mae, for which the Company retains some risk of loss, were to default and all of the collateral underlying these loans was determined to be without value at the time of settlement. Therefore, the maximum quantifiable contingent liability is not representative of the actual loss the Company would be expected to incur. The estimated fair value of the associated loss share guarantee recorded as a liability on the Company's consolidated balance sheets was approximately $4 million at both December 31, 2017 and 2016. Refer to Note 1 for additional information. VISA INDEMNIFICATION As a member of the Visa USA network, Regions, along with other members, indemnified Visa USA against litigation. On October 3, 2007, Visa USA was restructured and acquired several Visa affiliates. In conjunction with this restructuring, Regions' indemnification of Visa USA was modified to cover specific litigation (“covered litigation”). A portion of Visa's proceeds from its IPO was put into escrow to fund the covered litigation. To the extent that the amount available under the escrow arrangement, or subsequent fundings of the escrow account resulting from reductions in the class B share conversion ratio, is insufficient to fully resolve the covered litigation, Visa will enforce the indemnification obligations of Visa USA's members for any excess amount. At this time, Regions has concluded that it is not probable that covered litigation exposure will exceed the class B share value.

Parent Company Only Financial S

Parent Company Only Financial Statements	12 Months Ended
	Dec. 31, 2017
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Parent Company Only Financial Statements	PARENT COMPANY ONLY FINANCIAL STATEMENTS Presented below are condensed financial statements of Regions Financial Corporation: Balance Sheets December 31 2017 2016 (In millions) Assets Interest-bearing deposits in other banks $ 1,693 $ 1,043 Loans to subsidiaries 20 20 Securities available for sale 18 20 Premises and equipment, net 46 42 Investments in subsidiaries: Banks 16,548 16,693 Non-banks 446 409 16,994 17,102 Other assets 303 453 Total assets $ 19,074 $ 18,680 Liabilities and Stockholders’ Equity Long-term borrowings $ 2,702 $ 1,728 Other liabilities 180 288 Total liabilities 2,882 2,016 Stockholders’ equity: Preferred stock 820 820 Common stock 12 13 Additional paid-in capital 15,858 17,092 Retained earnings 1,628 666 Treasury stock, at cost (1,377 ) (1,377 ) Accumulated other comprehensive income (loss), net (749 ) (550 ) Total stockholders’ equity 16,192 16,664 Total liabilities and stockholders’ equity $ 19,074 $ 18,680 Statements of Income Year Ended December 31 2017 2016 2015 (In millions) Income: Dividends received from subsidiaries $ 1,300 $ 1,190 $ 860 Interest from subsidiaries 6 7 7 Insurance proceeds — — 91 Other 2 4 — 1,308 1,201 958 Expenses: Salaries and employee benefits 65 56 51 Interest 80 73 60 Furniture and equipment expense 4 3 1 Professional, legal and regulatory expenses — 2 3 Other 68 89 81 217 223 196 Income before income taxes and equity in undistributed earnings of subsidiaries 1,091 978 762 Income tax benefit (65 ) (66 ) (45 ) Income from continuing operations 1,156 1,044 807 Discontinued operations: Income (loss) from discontinued operations before income taxes 8 8 (22 ) Income tax expense (benefit) 2 3 (9 ) Income (loss) from discontinued operations, net of tax 6 5 (13 ) Income before equity in undistributed earnings of subsidiaries and preferred dividends 1,162 1,049 794 Equity in undistributed earnings of subsidiaries: Banks 73 102 257 Non-banks 28 12 11 101 114 268 Net income 1,263 1,163 1,062 Preferred stock dividends (64 ) (64 ) (64 ) Net income available to common shareholders $ 1,199 $ 1,099 $ 998 Statements of Cash Flows Year Ended December 31 2017 2016 2015 (In millions) Operating activities: Net income $ 1,263 $ 1,163 $ 1,062 Adjustments to reconcile net cash from operating activities: Equity in undistributed earnings of subsidiaries (101 ) (114 ) (268 ) Depreciation, amortization and accretion, net 2 2 1 Loss on sale of assets 1 — — Loss on early extinguishment of debt — 14 — Net change in operating assets and liabilities: Other assets (19 ) 33 16 Other liabilities 2 (38 ) (213 ) Other 41 68 48 Net cash from operating activities 1,189 1,128 646 Investing activities: (Investment in) / repayment of investment in subsidiaries 141 (60 ) (239 ) Principal payments received on loans to subsidiaries — — 10 Principal advances on loans to subsidiaries — (10 ) (10 ) Proceeds from sales and maturities of securities available for sale 9 8 6 Purchases of securities available for sale (6 ) (8 ) (7 ) Net (purchases of) / proceeds from sales of assets 6 (1 ) (43 ) Other, net 2 — — — Net cash from investing activities 152 (71 ) (283 ) Financing activities: Proceeds from long-term borrowings 999 1,107 — Payments on long-term borrowings — (658 ) (500 ) Cash dividends on common stock (346 ) (317 ) (304 ) Cash dividends on preferred stock (64 ) (64 ) (64 ) Repurchase of common stock (1,275 ) (839 ) (623 ) Other (5 ) (2 ) 12 Net cash from financing activities (691 ) (773 ) (1,479 ) Net change in cash and cash equivalents 650 284 (1,116 ) Cash and cash equivalents at beginning of year 1,043 759 1,875 Cash and cash equivalents at end of year $ 1,693 $ 1,043 $ 759

Summary of Significant Accoun35

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Consolidation, Subsidiaries or Other Investments, Consolidated Entities, Policy [Policy Text Block]	BASIS OF PRESENTATION AND PRINCIPLES OF CONSOLIDATION The consolidated financial statements include the accounts of Regions, its subsidiaries and certain VIEs. Significant intercompany balances and transactions have been eliminated. Regions considers a voting rights entity to be a subsidiary and consolidates it if Regions has a controlling financial interest in the entity. VIEs are consolidated if Regions has the power to direct the activities of the VIE that significantly impact financial performance and has the obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE (i.e., Regions is the primary beneficiary). The determination of whether Regions is the primary beneficiary of a VIE is reassessed on an ongoing basis. Investments in companies which are not VIEs but in which Regions has significant influence over the operating and financing decisions, are accounted for using the equity method of accounting. Investments in VIEs, where Regions is not the primary beneficiary of a VIE, are accounted for using either the proportional amortization method or the equity method of accounting. These investments are included in other assets in the consolidated balance sheets. The maximum potential exposure to losses relative to investments in VIEs is generally limited to the sum of the outstanding balance, future funding commitments and any related loans to the entity. Loans to these entities are underwritten in substantially the same manner as are other loans and are generally secured. Refer to Note 2 for additional disclosures regarding Regions’ significant VIEs. Unconsolidated equity investments that do not meet the criteria to be accounted for under the equity method are accounted for under the cost method. Cost method investments are included in other assets in the consolidated balance sheets and dividends received or receivable from these investments are included as a component of other non-interest income in the consolidated statements of income.
Discontinued Operations, Policy [Policy Text Block]	DISCONTINUED OPERATIONS On January 11, 2012, Regions entered into an agreement to sell Morgan Keegan and related affiliates. The transaction closed on April 2, 2012. Results of operations for the entities sold are presented separately as discontinued operations for all periods presented on the consolidated statements of income. Other expenses related to the transaction are also included in discontinued operations. See Note 3 and Note 24 for further discussion.
Cash and Cash Equivalents, Policy [Policy Text Block]	CASH EQUIVALENTS AND CASH FLOWS Cash equivalents represent assets that can be converted into cash immediately. At Regions, these assets include cash and due from banks, interest-bearing deposits in other banks, and federal funds sold and securities purchased under agreements to resell. Cash flows from loans, either originated or acquired, are classified at that time according to management’s intent to either sell or hold the loan for the foreseeable future. When management’s intent is to sell the loan, the cash flows of that loan are presented as operating cash flows. When management’s intent is to hold the loan for the foreseeable future, the cash flows of that loan are presented as investing cash flows.
Repurchase Agreements, Collateral, Policy [Policy Text Block]	SECURITIES PURCHASED UNDER AGREEMENTS TO RESELL AND SECURITIES SOLD UNDER AGREEMENTS TO REPURCHASE Securities purchased under agreements to resell and securities sold under agreements to repurchase are treated as collateralized financing transactions. It is Regions’ policy to take possession of securities purchased under resell agreements either through direct delivery or a tri-party agreement.
Marketable Securities, Trading Securities, Policy [Policy Text Block]	TRADING ACCOUNT SECURITIES Trading account securities, which are primarily held for employee benefit purposes as a funding mechanism for related liabilities, consist of debt and marketable equity securities and are carried at estimated fair value. See the “Fair Value Measurements” section below for discussion of determining fair value. Gains and losses, both realized and unrealized, are included in other non-interest income.
Investment, Policy [Policy Text Block]	SECURITIES Management determines the appropriate accounting classification of debt and equity securities at the time of purchase, based on intent, and periodically re-evaluates such designations. Debt securities are classified as securities held to maturity when the Company has the intent and ability to hold the securities to maturity. Securities held to maturity are presented at amortized cost. Debt securities not classified as securities held to maturity or trading account securities, and marketable equity securities not classified as trading account securities are classified as securities available for sale. Securities available for sale are presented at estimated fair value with changes in unrealized gains and losses, net of taxes, reported as a component of accumulated other comprehensive income (loss). See the “Fair Value Measurements” section below for discussion of determining fair value. The amortized cost of debt securities classified as securities held to maturity and securities available for sale is adjusted for amortization of premiums and accretion of discounts to maturity, or in the case of mortgage-backed securities, over the estimated life of the security, using the interest method. Such amortization or accretion is included in interest income on securities. Realized gains and losses are included in net securities gains (losses). The cost of securities sold is based on the specific identification method. The Company reviews its securities portfolio on a regular basis to determine if there are any conditions indicating that a security has other-than-temporary impairment. Factors considered in this determination include the length of time and the extent to which the market value has been below cost for equity securities. For debt securities, factors include the credit standing of the issuer, whether the Company expects to receive all scheduled principal and interest payments, Regions’ intent to sell and whether it is more likely than not that the Company will have to sell the security before its market value recovers. For debt securities, activity related to the credit loss component of other-than-temporary impairment is recognized in earnings as part of net securities gains (losses). Additionally, the Company recognizes impairment of available for sale equity securities when the cost basis is above the highest traded price within the past six months; the cost basis of the securities is adjusted to current estimated fair value with the entire offset recorded in the statement of income. Refer to Note 4 for further detail and information on securities.
Finance, Loan and Lease Receivables, Held-for-sale, Policy [Policy Text Block]	LOANS HELD FOR SALE Regions’ loans held for sale include commercial loans, investor real estate loans and residential real estate mortgage loans. Loans held for sale are recorded at either estimated fair value, if the fair value option is elected, or the lower of cost or estimated fair value. Regions has elected to account for residential real estate mortgages originated with the intent to sell at fair value. Intent is established for these conforming residential real estate mortgage loans when Regions enters into an interest rate lock commitment. Gains and losses on these residential mortgage loans held for sale for which the fair value option has been elected are included in mortgage income. Certain commercial mortgage loans held for sale where management has elected the fair value option are recorded at fair value. Gains and losses on commercial mortgage loans held for sale for which the fair value option has been elected are included in capital markets fee income and other. Regions also transfers certain commercial, investor real estate, and residential real estate mortgage portfolio loans to held for sale when management has the intent to sell in the near term. These held for sale loans are recorded at the lower of cost or estimated fair value. At the time of transfer, write-downs on the loans are recorded as charge-offs and a new cost basis is established. Any subsequent lower of cost or market adjustment is determined on an individual loan basis and is recognized in other non-interest expense. Gains and losses on the sale of non-performing commercial and investor real estate loans are included in other non-interest expense when realized as such amounts are viewed as credit costs. Gains and losses on sales of performing loans are included in non-interest income. See the “Fair Value Measurements” section below for discussion of determining estimated fair value.
Receivables, Policy [Policy Text Block]	LOANS Loans that management has the intent and ability to hold for the foreseeable future or until maturity or payoff are considered loans held for investment (or portfolio loans). Loans held for investment are carried at the principal amount outstanding, net of premiums, discounts, unearned income and deferred loan fees and costs. Regions' loans balance is comprised of commercial, investor real estate and consumer loans. Interest income on all types of loans is accrued based on the contractual interest rate and the principal amount outstanding using methods that approximate the interest method, except for those loans classified as non-accrual. Premiums and discounts on purchased loans and non-refundable loan origination and commitment fees, net of direct costs of originating or acquiring loans, are deferred and recognized over the estimated lives of the related loans as an adjustment to the loans’ constant effective yield, which is included in interest income on loans. See Note 5 for further detail and information on loans. Regions engages in both direct and leveraged lease financing. The net investment in direct financing leases is the sum of all minimum lease payments and estimated residual values, less unearned income. Unearned income is recognized over the terms of the leases to produce a constant effective yield. The net investment in leveraged leases is the sum of all lease payments (less non-recourse debt payments) and estimated residual values, less unearned income. Income from leveraged leases is recognized over the term of the leases based on the unrecovered equity investment. Regions determines past due or delinquency status of a loan based on contractual payment terms. Commercial and investor real estate loans are placed on non-accrual if any of the following conditions occur: 1) collection in full of contractual principal and interest is no longer reasonably assured (even if current as to payment status), 2) a partial charge-off has occurred, unless the loan has been brought current under its contractual terms (original or restructured terms) and the full originally contracted principal and interest is considered to be fully collectible, or 3) the loan is delinquent on any principal or interest for 90 days or more unless the obligation is secured by collateral having a net realizable value (estimated fair value less costs to sell) sufficient to fully discharge the obligation and the loan is in the legal process of collection. Factors considered regarding full collection include assessment of changes in borrower’s cash flow, valuation of underlying collateral, ability and willingness of guarantors to provide credit support, and other conditions. Charge-offs on commercial and investor real estate loans are primarily based on the facts and circumstances of the individual loan and occur when available information confirms the loan is not or will not be fully collectible. Factors considered in making these determinations are the borrower’s and any guarantor’s ability and willingness to pay, the status of the account in bankruptcy court (if applicable), and collateral value. Commercial and investor real estate loan relationships of $250,000 or less are subject to charge-off or charge down to net realizable value at 180 days past due, based on collateral value. Non-accrual and charge-off decisions for consumer loans are dictated by the FFIEC's Uniform Retail Credit Classification and Account Management Policy which establishes standards for the classification and treatment of consumer loans. The charge-off process drives consumer non-accrual status as follows. If a consumer loan secured by real estate in a first lien position (residential first mortgage or home equity) becomes 180 days past due, Regions evaluates the loan for non-accrual status and potential charge-off based on net loan to value exposure. For home equity loans in a second lien position, the evaluation is performed at 120 days past due. If a loan is secured by collateral having a net realizable value sufficient to fully discharge the obligation, then a partial write-down is not necessary and the loan remains on accrual status, provided it is in the process of legal collection. If a partial charge-off is necessary as a result of the evaluation, then the remaining balance is placed on non-accrual. Consumer loans not secured by real estate are generally charged-off in full at either 120 days past due for closed-end loans, 180 days past due for open-end loans other than credit cards or the end of the month in which the loan becomes 180 days past due for credit cards. When loans are placed on non-accrual status, the accrual of interest, amortization of loan premium, accretion of loan discount and amortization/accretion of deferred net loan fees/costs are discontinued. When a commercial or investor real estate loan is placed on non-accrual status, uncollected interest accrued in the current year is reversed and charged to interest income. Uncollected interest accrued from prior years on commercial and investor real estate loans placed on non-accrual status in the current year is charged against the allowance for loan losses. When a consumer loan is placed on non-accrual status, all uncollected interest accrued is reversed and charged to interest income due to immateriality. Interest collections on commercial and investor real estate non-accrual loans are applied as principal reductions. Interest collections on consumer loans are recorded using the cash basis, due to immateriality. All loans on non-accrual status may be returned to accrual status and interest accrual resumed if all of the following conditions are met: 1) the loan is brought contractually current as to both principal and interest, 2) future payments are reasonably expected to continue being received in accordance with the terms of the loan and repayment ability can be reasonably demonstrated, and 3) the loan has been performing for at least six months.
Financing Receivable, Allowance for Credit Losses, Policy for Uncollectible Amounts [Policy Text Block]	ALLOWANCE FOR CREDIT LOSSES Regions' allowance for credit losses (“allowance”) consists of two components: the allowance for loan losses, which is recorded as a contra-asset to loans, and the reserve for unfunded credit commitments, which is recorded in other liabilities. The allowance is reduced by actual losses (charge-offs) and increased by recoveries, if any. Regions charges losses against the allowance in the period the loss is confirmed. All adjustments to the allowance for loan losses are charged directly to expense through the provision for loan losses. All adjustments to the reserve for unfunded credit commitments are recorded in other non-interest expense. The allowance is maintained at a level believed appropriate by management to absorb probable credit losses inherent in the loan and unfunded credit commitment portfolios in accordance with GAAP and regulatory guidelines. Management’s determination of the appropriateness of the allowance is a quarterly process and is based on an evaluation and rating of the loan portfolio segments, historical loan loss experience, current economic conditions, collateral values securing loans, levels of problem loans, volume, growth, quality and composition of the loan portfolio, regulatory guidance, and other relevant factors. Changes in any of these, or other factors, or the availability of new information, could require that the allowance be adjusted in future periods. Actual losses could vary from management’s estimates. Management attributes portions of the allowance to loans that it evaluates and determines to be impaired and to groups of loans that it evaluates collectively. However, the entire allowance is available to cover all charge-offs that arise from the loan portfolio. CALCULATION OF ALLOWANCE FOR CREDIT LOSSES Commercial and Investor Real Estate Components Impaired Loans Loans deemed to be impaired include non-accrual loans, excluding consumer loans, and all TDRs. Regions considers the current value of collateral, credit quality of any guarantees, guarantor’s liquidity and willingness to repay, the loan structure, and other factors when evaluating whether an individual loan is impaired. Other factors may include the industry and geographic region of the borrower, size and financial condition of the borrower, cash flow and leverage of the borrower and Regions’ evaluation of the borrower’s management. For non-accrual commercial and investor real estate loans (including TDRs) equal to or greater than $2.5 million , the allowance for loan losses is based on a note-level evaluation considering the facts and circumstances specific to each borrower. For these loans, Regions measures the level of impairment based on the present value of the estimated cash flows, the estimated value of the collateral or, if available, the observable market price. Regions generally uses the estimated cash flow method to measure impairment. For commercial and investor real estate accruing TDRs and all non-accruing loans less than $2.5 million , the allowance for loan losses is based on a discounted cash flow analysis performed at the note level, where estimated projected cash flows reflect credit losses based on statistical information (including historical default information) derived from loans with similar risk characteristics (e.g., credit quality indicator and product type) using PDs and LGDs as described in the following paragraph. Non-Impaired Loans For all other commercial and investor real estate loans, the allowance for loan losses is calculated at a pool level based on credit quality indicators and product type. Statistically determined PDs and LGDs are calculated based on historical default and loss information for similar loans. The historical default and loss information is measured over a relevant period for each loan pool. The pool level allowance is calculated using the PD and LGD estimates and is adjusted as appropriate based on additional analysis of long-term average loss experience compared to previously forecasted losses, external loss data and other risks identified from current economic conditions and credit quality trends. Various one year PD measurements are used in conjunction with life-of-loan LGD measurements to estimate incurred losses. As a result, losses are effectively covered over a two to three year period for loans that are currently in default and those estimated to default within the next twelve months. Consumer Components For consumer loans, the classes are segmented into pools of loans with similar risk characteristics. For most consumer loan pools, historical losses are the primary factor in establishing the allowance allocated to each pool. The twelve month loss rate is the basis for the allocation and it may be adjusted based on deteriorating trends, portfolio growth, or other factors determined by management to be relevant. The allowance for loan losses for the residential first mortgage non-TDR pool is calculated based on a twelve-month historical loss rate segmented based on the following risk characteristics: past due and accrual status and further by geography, property use and amortization type for accruing, non-past due loans. The allowance for loan losses for residential first mortgage TDRs is calculated based on a discounted cash flow analysis on pools of homogeneous loans. Cash flows are projected using the restructured terms and then discounted at the original note rate. The projected cash flows assume a default rate, which is based on historical performance of residential first mortgage TDRs. The allowance for loan losses for the home equity pool is calculated based on a twelve-month historical loss rate segmented based on the following risk characteristics: lien position, TDR status, geography, non-accrual and past due status, and refreshed FICO scores for accruing, non-past due loans. Qualitative Factors While quantitative allowance methodologies strive to reflect all risk factors, any estimate involves assumptions and uncertainties resulting in some level of imprecision. Imprecision exists in the estimation process due to the inherent time lag of obtaining information and variations between estimates and actual outcomes. Regions adjusts the allowance in consideration of quantitative and qualitative factors which may not be directly measured in the note-level or pooled calculations, including, but not limited to: • Credit quality trends, • Loss experience in particular portfolios, • Macroeconomic factors such as unemployment, real estate prices, or commodity pricing volatility, • Changes in risk selection and underwriting standards, • Shifts in credit quality of consumer customers which is not yet reflected in the historical data. Reserve for Unfunded Credit Commitments In order to estimate a reserve for unfunded commitments, Regions uses a process consistent with that used in developing the allowance for loan losses. The reserve is based on an EAD multiplied by a PD multiplied by an LGD. The EAD is estimated based on an analysis of historical funding patterns for defaulted loans in various categories. The PD and LGD align with the statistically-calculated parameters used to calculate the allowance for loan losses for various pools, which are based on credit quality indicators and product type. The methodology applies to commercial and investor real estate credit commitments and standby letters of credit that are not unconditionally cancellable. Refer to Note 6 for further discussion regarding the calculation of the allowance for credit losses.
Loans and Leases Receivable, Troubled Debt Restructuring Policy [Policy Text Block]	TDRs TDRs are loans in which the borrower is experiencing financial difficulty at the time of restructuring, and Regions has granted a concession to the borrower. TDRs are undertaken in order to improve the likelihood of recovery on the loan and may take the form of modifications made with the stated interest rate lower than the current market rate for new debt with similar risk, other modifications to the structure of the loan that fall outside of normal underwriting policies and procedures, or in limited circumstances forgiveness of principal and/or interest. TDRs can involve loans remaining on non-accrual, moving to non-accrual, or continuing on accrual status, depending on the individual facts and circumstances of the borrower. TDRs are subject to policies governing accrual/non-accrual evaluation consistent with all other loans of the same product type as discussed in the “Loans” section above. All loans with the TDR designation are considered to be impaired, even if they are accruing. See the “Calculation of Allowance For Credit Losses” section above for Regions’ allowance for loan losses methodology related to TDRs. The CAP was designed to evaluate potential consumer loan participants as early as possible in the life cycle of the troubled loan (as described in Note 6). Many of the modifications are finalized without the borrower ever reaching the applicable number of days past due, and therefore the loan may never be placed on non-accrual. Accordingly, given the positive impact of the restructuring on the likelihood of recovery of cash flows due under the modified terms, accrual status continues to be appropriate for these loans.
Other Earning Assets [Policy Text Block]	OTHER EARNING ASSETS Other earning assets consist primarily of investments in FRB stock, FHLB stock, and operating lease assets. See Note 8 for additional information. INVESTMENTS IN FEDERAL RESERVE BANK AND FEDERAL HOME LOAN BANK STOCK Ownership of FRB and FHLB stock is a requirement for all banks seeking membership into and access to the services provided by these banking systems. These shares are accounted for at amortized cost, which approximates fair value. INVESTMENTS IN OPERATING LEASES Investments in operating leases represent the assets underlying the related lease contracts and are reported at cost, less accumulated depreciation and net of origination fees and costs. Depreciation on these assets is generally provided on a straight-line basis over the lease term down to an estimated residual value. Regions periodically evaluates its depreciation rate for leased assets based on projected residual values and adjusts depreciation expense over the remaining life of the lease if deemed appropriate. Regions also evaluates the current value of the operating lease assets and tests for impairment when indicators of impairment are present. Income from operating lease assets includes lease origination fees, net of lease origination costs, and is recognized as operating lease revenue on a straight line basis over the scheduled lease term. The accrual of revenue on operating leases is generally discontinued at the time an account is determined to be uncollectible. Operating lease revenue and the depreciation expense on the related operating lease assets are included as components of net interest income and other financing income on the consolidated statements of income. When a leased asset is returned, its remaining value is reclassified from other earning assets to other assets and recorded at the lower of cost or estimated fair value, less costs to sell, on Regions' consolidated balance sheet. Impairment of the operating lease asset, as well as residual value gains and losses at the end of the lease term are recorded through other non-interest income.
Property, Plant and Equipment, Policy [Policy Text Block]	PREMISES AND EQUIPMENT Premises and equipment are stated at cost, less accumulated depreciation and amortization, as applicable. Land is carried at cost. Depreciation expense is computed using the straight-line method over the estimated useful lives of the assets. Leasehold improvements are amortized using the straight-line method over the estimated useful lives of the improvements (or the terms of the leases, if shorter). Generally, premises and leasehold improvements are depreciated or amortized over 7 - 40 years. Furniture and equipment are generally depreciated or amortized over 3 - 10 years. Premises and equipment are evaluated for impairment at least annually, or more often if events or circumstances indicate that the carrying value of the asset may not be recoverable. Maintenance and repairs are charged to non-interest expense in the consolidated statements of income. Improvements that extend the useful life of the asset are capitalized to the carrying value and depreciated. See Note 9 for detail of premises and equipment. Regions enters into lease transactions for the right to use assets. These leases vary in term and, from time to time, include incentives and/or rent escalations. Examples of incentives include periods of “free” rent and leasehold improvement incentives. Regions recognizes incentives and escalations on a straight-line basis over the lease term as a reduction of or increase to rent expense, as applicable, within net occupancy expense in the consolidated statements of income.
Goodwill and Intangible Assets, Policy [Policy Text Block]	INTANGIBLE ASSETS Intangible assets include goodwill, which is the excess of cost over the fair value of net assets of acquired businesses, and other identifiable intangible assets. Other identifiable intangible assets primarily include the following: 1) core deposit intangible assets, which are amounts recorded related to the value of acquired indeterminate maturity deposits, 2) amounts capitalized related to the value of acquired customer relationships, 3) amounts recorded related to employment agreements with certain individuals of acquired entities, and 4) the Fannie Mae DUS license. Core deposit intangibles and certain other identifiable intangibles are amortized on an accelerated basis over their expected useful lives. The Company’s goodwill is tested for impairment on an annual basis in the fourth quarter, or more often if events or circumstances indicate that there may be impairment. Regions assesses the following indicators of goodwill impairment for each reporting period: • Recent operating performance, • Changes in market capitalization, • Regulatory actions and assessments, • Changes in the business climate (including legislation, legal factors and competition), • Company-specific factors (including changes in key personnel, asset impairments, and business dispositions), and • Trends in the banking industry. Adverse changes in the economic environment, declining operations, or other factors could result in a decline in the implied estimated fair value of goodwill. A goodwill impairment test includes two steps. Step One, used to identify potential impairment, compares the estimated fair value of a reporting unit with its carrying amount, including goodwill. If the estimated fair value of a reporting unit exceeds its carrying amount, goodwill of the reporting unit is considered not impaired. If the carrying amount of a reporting unit exceeds its estimated fair value, the second step of the goodwill impairment test is performed to measure the amount of impairment loss, if any. Step Two of the goodwill impairment test compares the implied estimated fair value of reporting unit goodwill with the carrying amount of that goodwill. If the carrying amount of goodwill for that reporting unit exceeds the implied estimated fair value of that unit’s goodwill, an impairment loss is recognized in other non-interest expense in an amount equal to that excess. For purposes of performing Step One of the goodwill impairment test, Regions uses both income and market approaches to value its reporting units. The income approach, which is the primary valuation approach, consists of discounting projected long-term future cash flows, which are derived from internal forecasts and economic expectations for the respective reporting units. The significant inputs to the income approach include expected future cash flows, the long-term target equity ratios, and the discount rate. Regions utilizes the CAPM in order to derive the base discount rate. The inputs to the CAPM include the 20-year risk-free rate, 5-year beta for a select peer set, and the market risk premium, all based on published data. To determine the estimated cost of equity for each reporting unit, a size premium is added (also based on a published source) as well as a company-specific risk premium (based on business model and market perception of risk) to the base discount rate. Regions uses both the GCM and the GTM as its market approaches. The GCM applies a value multiplier derived from each reporting unit’s peer group to tangible book value (for Corporate Bank and Consumer Bank) or price to earnings ratio (for Wealth Management) and an implied control premium to each reporting unit. The control premium is evaluated and compared to similar financial services transactions considering the absolute and relative potential revenue synergies and cost savings. The GTM applies a value multiplier to a financial metric of each reporting unit based on comparable observed purchase transactions in the financial services industry for the reporting unit (where available). For purposes of performing Step Two of the goodwill impairment test, if applicable, Regions compares the implied estimated fair value of the reporting unit goodwill with the carrying amount of that goodwill. In order to determine the implied estimated fair value, a full purchase price allocation would be performed in the same manner as if a business combination had occurred. As part of the Step Two analysis, Regions estimates the fair value of all of the assets and liabilities of the reporting unit, including unrecognized assets and liabilities. The related valuation methodologies for certain material financial assets and liabilities are discussed in the “Fair Value Measurements” section below. Other identifiable intangible assets, primarily core deposit intangibles, purchased credit card relationships and other acquired customer relationships, are reviewed at least annually (usually in the fourth quarter) for events or circumstances that could impact the recoverability of the intangible asset. These events could include loss of core deposits, significant losses of credit card or other types of acquired customer accounts and/or balances, increased competition or adverse changes in the economy. To the extent other identifiable intangible assets are deemed unrecoverable, impairment losses are recorded in other non-interest expense and reduce the carrying amount of the asset. Refer to Note 10 for further detail and discussion of the results of the goodwill and other identifiable intangibles impairment tests.
Transfers and Servicing of Financial Assets, Policy [Policy Text Block]	ACCOUNTING FOR TRANSFERS AND SERVICING OF FINANCIAL ASSETS Regions accounts for transfers of financial assets as sales when control over the transferred assets is surrendered. Control is generally considered to have been surrendered when 1) the transferred assets are legally isolated from the Company or its consolidated affiliates, even in bankruptcy or other receivership, 2) the transferee has the right to pledge or exchange the assets with no conditions that constrain the transferee and provide more than a trivial benefit to the Company, and 3) the Company does not maintain the obligation or unilateral ability to reclaim or repurchase the assets. If these sale criteria are met, the transferred assets are removed from the Company’s balance sheet and a gain or loss on sale is recognized. If not met, the transfer is recorded as a secured borrowing, and the assets remain on the Company’s balance sheet, the proceeds from the transaction are recognized as a liability, and gain or loss on sale is deferred until the sale criterion are achieved. Regions has elected to account for its residential MSRs using the fair value measurement method. Under the fair value measurement method, residential MSRs are measured at estimated fair value each period with changes in fair value recorded as a component of mortgage income. The fair value of residential MSRs is calculated using various assumptions including future cash flows, market discount rates, expected prepayment rates, servicing costs and other factors. A significant change in prepayments of residential mortgages in the servicing portfolio could result in significant valuation adjustments, thus creating potential volatility in the carrying amount of residential MSRs. The valuation method relies on an OAS to consider prepayment risk and equate the asset's discounted cash flows to its market price. See the “Fair Value Measurements” section below for additional discussion regarding determination of fair value. Regions is a DUS lender. The DUS program provides liquidity to the multi-family housing market. Regions' related commercial MSRs are recorded in other assets on the consolidated balance sheets at the lower of cost or estimated fair value and are amortized in proportion to, and over the estimated period that net servicing income is expected to be received based on projections of the amount and timing of estimated future net cash flows. The amount and timing of estimated future net cash flows are updated based on actual results and updated projections. Regions periodically evaluates its commercial MSRs for impairment. Regions has a one-third loss share guarantee associated with the majority of the DUS servicing portfolio. The other two-thirds loss share guarantee is retained by Fannie Mae. The estimated fair value of the loss share guarantee is recorded in other liabilities on the consolidated balance sheets. Refer to Note 7 for further information on servicing of financial assets.
Finance, Loan and Lease Receivables, Held for Investments, Foreclosed Assets Policy [Policy Text Block]	FORECLOSED PROPERTY AND OTHER REAL ESTATE Other real estate and certain other assets acquired in satisfaction of indebtedness (“foreclosure”) are carried in other assets at the lower of the recorded investment in the loan or estimated fair value less estimated costs to sell the property. At the date of transfer from the loan portfolio, if the recorded investment in the loan exceeds the property’s estimated fair value less estimated costs to sell, a write-down is recorded against the allowance. Regions allows a period of up to 60 days after the date of transfer to record finalized write-downs as charge-offs against the allowance in order to properly accumulate all related invoices and updated valuation information, if necessary. Subsequent to transfer, Regions obtains valuations from professional valuation experts and/or third party appraisers on at least an annual basis. See the “Fair Value Measurements” section below for additional discussion regarding determination of fair value. Subsequent to transfer and the additional 60 days, any further write-downs are recorded as other non-interest expense. Gain or loss on the sale of foreclosed property and other real estate is included in other non-interest expense. At December 31, 2017 and 2016 , the carrying values of foreclosed properties were immaterial. From time to time, assets classified as premises and equipment are transferred to held for sale for various reasons. These assets are carried in other assets at the lower of the recorded investment in the asset or estimated fair value less estimated cost to sell based upon the property’s appraised value at the date of transfer. Any write-downs of property held for sale are recorded as other non-interest expense.
Derivatives, Policy [Policy Text Block]	DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES The Company enters into derivative financial instruments to manage interest rate risk, facilitate asset/liability management strategies and manage other exposures. These instruments primarily include interest rate swaps, options on interest rate swaps, options including interest rate caps and floors, Eurodollar futures, forward rate contracts and forward sale commitments. All derivative financial instruments are recognized on the consolidated balance sheets as other assets or other liabilities, as applicable, at estimated fair value. Regions enters into master netting agreements with counterparties and/or requires collateral to cover exposures. In at least some cases, counterparties post collateral at a zero threshold regardless of credit rating. The majority of interest rate derivatives traded by Regions with dealing counterparties are subject to mandatory clearing through a central clearinghouse. The counterparty risk for cleared trades effectively moves from the executing broker to the clearinghouse allowing Regions to benefit from the risk mitigation controls in place at the respective clearinghouse. Interest rate swaps are agreements to exchange interest payments based upon notional amounts. Interest rate swaps subject Regions to market risk associated with changes in interest rates, changes in interest rate volatility as well as the credit risk that the counterparty will fail to perform. Option contracts involve rights to buy or sell financial instruments on a specified date or over a period at a specified price. These rights do not have to be exercised. Some option contracts such as interest rate floors, involve the exchange of cash based on changes in specified indices. Interest rate floors are contracts to hedge interest rate declines based on a notional amount, generally associated with a principal balance at risk. Interest rate floors subject Regions to market risk associated with changes in interest rates, changes in interest rate volatility, as well as the credit risk that the counterparty will fail to perform. Forward rate contracts are commitments to buy or sell financial instruments at a future date at a specified price or yield. Regions primarily enters into forward rate contracts on marketable instruments, which expose Regions to market risk associated with changes in the value of the underlying financial instrument, as well as the credit risk that the counterparty will fail to perform. Eurodollar futures are futures contracts on Eurodollar deposits. Eurodollar futures subject Regions to market risk associated with changes in interest rates. Because futures contracts are cash settled daily through a margining process in an exchange, there is minimal credit risk associated with Eurodollar futures. Forward sale commitments are sales of securities at a specified price at a future date. Forward sale commitments subject Regions to market risk associated with changes in market value, as well as the credit risk that the counterparty will fail to perform. The Company elects to account for certain derivative financial instruments as accounting hedges which, based on the exposure being hedged, are either fair value or cash flow hedges. Fair value hedge relationships mitigate exposure to the change in fair value of an asset, liability or firm commitment. Under the fair value hedging model, gains or losses attributable to the change in fair value of the derivative instrument, as well as the gains and losses attributable to the change in fair value of the hedged item, are recognized in other non-interest expense in the period in which the change in fair value occurs. Hedge ineffectiveness is recognized as other non-interest expense to the extent the changes in fair value of the derivative do not offset the changes in fair value of the hedged item. The corresponding adjustment to the hedged asset or liability is included in the basis of the hedged item, while the corresponding change in the fair value of the derivative instrument is recorded as an adjustment to other assets or other liabilities, as applicable. Cash flow hedge relationships mitigate exposure to the variability of future cash flows or other forecasted transactions. For cash flow hedge relationships, the effective portion of the gain or loss related to the derivative instrument is recognized as a component of accumulated other comprehensive income (loss). Ineffectiveness is measured by comparing the change in fair value of the respective derivative instrument and the change in fair value of a “perfectly effective” hypothetical derivative instrument. Ineffectiveness will be recognized in earnings only if it results from an overhedge (i.e. the change in the value of the derivative exceeds the change related to the hedged exposure). The ineffective portion of the gain or loss related to the derivative instrument, if any, is recognized in earnings as other non-interest expense during the period of change. Amounts recorded in accumulated other comprehensive income (loss) are recognized in earnings in the period or periods during which the hedged item impacts earnings. The Company formally documents all hedging relationships, as well as its risk management objective and strategy for entering into various hedge transactions. The Company performs periodic assessments to determine whether the hedging relationship has been highly effective in offsetting changes in fair values or cash flows of hedged items and whether the relationship is expected to continue to be highly effective in the future. If a hedge relationship is de-designated or if hedge accounting is discontinued because the hedged item no longer meets the definition of a firm commitment, or because it is probable that the forecasted transaction will not occur, the derivative will continue to be recorded as an other asset or other liability in the consolidated balance sheets at its estimated fair value, with changes in fair value recognized in other non-interest expense. Any asset or liability that was recorded pursuant to recognition of the firm commitment is removed from the consolidated balance sheets and recognized in other non-interest expense. Gains and losses that were unrecognized and aggregated in accumulated other comprehensive income (loss) pursuant to the hedge of a forecasted transaction are recognized immediately in other non-interest expense. Derivative contracts for which the Company has not elected to apply hedge accounting are classified as other assets or liabilities with gains and losses related to the change in fair value recognized in capital markets fee income and other or mortgage income, as applicable, in the statements of income during the period. These positions, as well as non-derivative instruments, are used to mitigate economic and accounting volatility related to customer derivative transactions, the mortgage pipeline and the fair value of residential MSRs. Regions enters into interest rate lock commitments, which are commitments to originate mortgage loans whereby the interest rate on the loan is determined prior to funding and the customers have locked into that interest rate. Accordingly, such commitments are recorded at estimated fair value with changes in fair value recorded in mortgage income or capital markets fee income and other, as applicable. Regions also has corresponding forward sale commitments related to these interest rate lock commitments, which are recorded at estimated fair value with changes in fair value recorded in mortgage income or capital markets fee income and other, as applicable. See the “Fair Value Measurements” section below for additional information related to the valuation of interest rate lock commitments. Regions enters into various derivative agreements with customers desiring protection from possible future market fluctuations. Regions manages the market risk associated with these derivative agreements in a trading portfolio. The contracts in this portfolio for which the Company has elected not to apply hedge accounting are marked-to-market through earnings and included in other assets and other liabilities. Concurrent with the election to use fair value measurement for residential MSRs, Regions began using various derivative instruments to mitigate the impact of changes in the fair value of residential MSRs in the statements of income. This effort may involve the use of various derivative instruments, including, but not limited to, forwards, futures, swaps and options. These derivatives are carried at estimated fair value, with changes in fair value reported in mortgage income. Refer to Note 21 for further discussion and details of derivative financial instruments and hedging activities.
Income Tax, Policy [Policy Text Block]	INCOME TAXES The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for expected future tax consequences. Under this method, deferred tax assets and liabilities are determined by applying the federal and state tax rates to the differences between financial statement carrying amounts and the corresponding tax bases of assets and liabilities. Deferred tax assets are also recorded for any tax attributes, such as tax credit and net operating loss carryforwards. The net balance of deferred tax assets and liabilities is reported in other assets or other liabilities in the consolidated balance sheets, as appropriate. Any effect of a change in federal and state tax rates on deferred tax assets and liabilities is recognized in income tax expense in the period that includes the enactment date. Excluding the effects of Tax Reform, as discussed in Note 20 and the "Recent Accounting Pronouncements and Accounting Changes" section below, the impact of changes in tax rates related to unrealized gains and losses included in accumulated other comprehensive income is immaterial. The Company reflects the expected amount of income tax to be paid or refunded during the year as current income tax expense or benefit, as applicable. The Company evaluates the realization of deferred tax assets based on all positive and negative evidence available at the balance sheet date. Realization of deferred tax assets is based on the Company’s judgments about relevant factors affecting their realization, including taxable income within any applicable carryback periods (post Tax Reform, NOL's generated by Regions cannot be carried back, but can be carried forward indefinitely), future projected taxable income, reversal of taxable temporary differences and other tax-planning strategies to maximize realization of the deferred tax assets. A valuation allowance is recorded for any deferred tax assets that are not more-likely-than-not to be realized. Income tax benefits generated from uncertain tax positions are accounted for using the recognition and cumulative-probability measurement thresholds. Based on the technical merits, if a tax benefit is not more-likely-than-not of being sustained upon examination, the Company records a liability for the recognized income tax benefit. If a tax benefit is more-likely-than-not of being sustained based on the technical merits, the Company utilizes the cumulative probability measurement and records an income tax benefit equivalent to the largest amount of tax benefit that is greater than 50 percent likely to be realized upon ultimate settlement with a taxing authority. The Company recognizes interest expense, interest income and penalties related to unrecognized tax benefits within current income tax expense. The Company applies the proportional amortization method in accounting for its qualified affordable housing investments. This method recognizes the amortized cost of the investment as a component of income tax expense. The deferral method of accounting is used for investments that generate investment tax credits. Under this method, the investment tax credits are recognized as a reduction of the related asset. Refer to Note 20 for further discussion regarding income taxes.
Treasury Stock and Share Repurchases [Policy Text Block]	TREASURY STOCK AND SHARE REPURCHASES The purchase of the Company’s common stock is recorded at cost. At the date of repurchase, stockholders' equity is reduced by the repurchase price. Upon retirement, or upon purchase for constructive retirement, treasury stock would be reduced by the cost of such stock with the excess of repurchase price over par or stated value recorded in additional paid-in capital. If the Company subsequently reissues treasury shares, treasury stock is reduced by the cost of such stock with differences recorded in additional paid-in capital or retained earnings, as applicable. Pursuant to recent share repurchase programs, shares repurchased were immediately retired, and therefore were not included in treasury stock. The Company's policy related to these share repurchases is to reduce its common stock based on the par value of the shares repurchased and to reduce its additional paid-in capital for the excess of the repurchase price over the par value.
Compensation Related Costs, Policy [Policy Text Block]	SHARE-BASED PAYMENTS Regions sponsors stock plans which most commonly include restricted stock (i.e., unvested common stock), restricted stock units, performance stock units and stock options. The Company accounts for share-based payments under the fair value recognition provisions whereby compensation cost is measured based on the estimated fair value of the award at the grant date and is recognized in the consolidated financial statements on a straight-line basis over the requisite service period for service-based awards. The fair value of restricted stock, restricted stock units or performance stock units is determined based on the closing price of Regions common stock on the date of grant. Historical data is also used to estimate future employee attrition, which is considered in calculating estimated forfeitures. Estimated forfeitures are adjusted when actual forfeitures differ from estimates, resulting in the recognition of compensation cost only for awards that vest. The effect of a change in estimated forfeitures is recognized through a cumulative catch-up adjustment that is included in compensation cost in the period of the change in estimate. The fair value of stock options where vesting is based on service is estimated at the date of grant using a Black-Scholes option pricing model and related assumptions. As compensation cost is recognized, a deferred tax asset is recorded that represents an estimate of the future tax deduction from exercise or release of restrictions. At the time the share-based awards are exercised, cancelled, have expired, or restrictions are released, the Company may be required to recognize an adjustment to tax expense depending on the market price of the Company’s common stock. See Note 17 for further discussion and details of share-based payments.
Pension and Other Postretirement Plans, Pensions, Policy [Policy Text Block]	EMPLOYEE BENEFIT PLANS Regions uses an expected long-term rate of return applied to the fair market value of assets as of the beginning of the year and the expected cash flows during the year for calculating the expected investment return on all pension plan assets. At a minimum, amortization of the net gain or loss included in accumulated other comprehensive income resulting from experience different from that assumed and from changes in assumptions is included as a component of net periodic benefit cost if, as of the beginning of the year, that net gain or loss exceeds 10 percent of the greater of the projected benefit obligation or the market value of plan assets. If amortization is required, the minimum amortization is that excess divided by the average remaining service period of active participating employees expected to receive benefits under the plans. Regions uses a third-party actuary to compute the remaining service period of active participating employees. This period reflects expected turnover, pre-retirement mortality, and other applicable employee demographics.
Revenue Recognition, Policy [Policy Text Block]	REVENUE RECOGNITION Interest Income The largest source of revenue for Regions is interest income. Interest income is recognized using the interest method driven by nondiscretionary formulas based on written contracts, such as loan agreements or securities contracts. Service Charges on Deposit Accounts Service charges on deposit accounts include non-sufficient fund fees and other service charges. Non-sufficient fund fees are earned when a depositor presents an item for payment in excess of available funds, and Regions, at its discretion, provides the necessary funds to complete the transaction. Regions generates other service charges by providing depositors proper safeguard and remittance of funds as well as by providing optional services for depositors, such as check imaging or treasury management, that are performed upon the depositor’s request. Charges for the proper safeguard and remittance of funds are recognized monthly, as the customer retains funds in the account. Regions recognizes revenue for other optional services at the point in time the customer uses the selected service to execute a transaction (e.g. execute an ACH wire). Card and ATM Fees Card and ATM fees include the combined amounts of credit card, debit card, and ATM related revenue. The majority of the fees are card interchange where Regions earns a fee for remitting cardholder funds (or extends credit) via a third party network to merchants. Regions satisfies performance obligations for each transaction at the point in time the card is used and the funds are remitted. The network establishes interchange fees that the merchant remits to Regions for each transaction, and Regions incurs costs from the network for facilitating the interchange with the merchant. Due to its inability to establish prices and direct activities of the related processing network’s service, Regions is deemed the agent in this arrangement and records interchange revenues net of related costs. Regions also pays consideration to certain commercial card holders based on interchange fees and contractual volume. These costs are recognized as a reduction to interchange income. Card and ATM fees also include ATM fee income generated from allowing a Regions cardholder to withdraw funds from a non-Regions ATM and from allowing a non-Regions cardholder to withdraw funds from a Regions ATM. Regions satisfies performance obligations for each transaction at the point in time that the withdrawal is processed. Regions does not direct activities of the related processing network’s service and recognizes revenue on a net basis as the agent in each transaction. Investment Management and Trust Fee Income Investment management and trust fee income represents revenue generated from asset management services provided to individuals, businesses, and institutions. Regions has a fiduciary responsibility to the beneficiary of the trust to perform agreed upon services which can include investing the assets, periodic reporting to the beneficiaries, and providing tax information regarding the trust. In exchange for these trust and custodial services, Regions collects fee income from beneficiaries as contractually determined via fee schedules. Regions’ performance obligations to customers are primarily satisfied over time as the services are performed and provided to the customer. Mortgage Income Mortgage income and related fees are recognized when earned as Regions services mortgage loans for others. Mortgage income also includes gains or losses on Regions’ sales of mortgage loans to other financial institutions or government agencies which are recognized as each sales transaction occurs. Capital Markets Fee Income and Other Regions generates capital markets fee revenue through capital raising activities which include revenue streams such as securities underwriting and placement, loan syndication and placement, as well as foreign exchange, derivatives, merger and acquisition and other advisory services. For those revenue streams, revenue is primarily recognized at a point in time which coincides with the satisfaction of a single performance obligation, typically the transaction closing. Securities underwriting and placement fees involve the issuing and distribution of securities for an underwriting fee from customers. The underwriting fee is a single performance obligation which is satisfied at the time that the transaction is closed, and the amount of the fee is either a fixed or variable percentage based on the deal value which is determinable at the time of deal closing. Regions generates revenue from affordable housing investments through the syndication of investment funds to third parties. Regions transfers the primary benefits of the investment to the customer and recognizes syndication revenue on the closing date of the transaction. Insurance Commissions and Fees Regions markets and sells insurance products and services which include property and casualty, life and health, mortgage insurance, and other specialty insurance and credit-related products to businesses and individuals. Regions acts as an insurance intermediary by matching the coverage needs of the customers with the offerings of insurance carriers. Regions’ performance obligation is generally satisfied at the time a customer enters into a bound insurance policy with the insurance carrier. Regions earns revenue in the form of commissions that are based on a percentage of the premium charged to the policyholder, or fixed fee income, in lieu of commissions, for services rendered. Regions is deemed the agent in this relationship and recognizes commissions on a net basis. Bank-Owned Life Insurance Bank-owned life insurance income primarily represents income earned from the appreciation of cash surrender value of insurance contracts held and the proceeds of insurance benefits. Regions recognizes revenue each period in the amount of the appreciation of the cash surrender value of the insurance policies. Revenue from the proceeds of insurance benefits is recognized at the time a claim is confirmed. Commercial Credit Fee Income Commercial credit fee income includes letters of credit fees and unused commercial commitment fees. Regions recognizes revenue for letters of credit fees over time. Regions recognizes revenue for unused commercial commitment fees on the date that the commitment expires. Investment Services Fee Income Investment services fee income represents income earned from investment advisory services. Through the use of third party carriers, Regions provides its customers with access to investment products that meet customers’ financial needs and investment objectives. Upon selection of an investment product, the customer enters into a policy with the carrier. Regions’ performance obligation is satisfied by fulfilling its responsibility to place customers in investment vehicles for which Regions earns commissions from the carrier based on agreed-upon fee percentages. In addition, Regions has a contractual relationship with a third party broker dealer to provide full service brokerage and investment advisory activities. As the principal in the arrangement, Regions recognizes the investment services commissions on a gross basis. Insurance Proceeds Insurance proceeds represent settlements from previously disclosed lawsuits. Revenue from insurance proceeds is recognized when the settlement proceeds are received. Securities Gains (Losses), Net Net securities gains or losses result from Regions’ asset/liability management process. Gains or losses on the sale of securities are recognized as each sales transaction occurs with the cost of securities sold based on the specific identification method. Market Value Adjustments on Employee Benefit Assets Regions holds assets for certain employee benefit purposes. Those assets are recorded at estimated fair value and the market value variations are recognized each period. Other Miscellaneous Income Other miscellaneous income represents a variety of revenue streams, including check order fees, wire transfer fees and other unusual gains, if any. For check order fees, Regions generates revenue by serving as the agent in connecting the customer to a third party check provider. For wire transfer fees, Regions generates revenue by providing wire transfer services to its depositors. In both instances Regions recognizes revenue at the time the service is provided.
Earnings Per Share, Policy [Policy Text Block]	PER SHARE AMOUNTS Earnings per common share is calculated by dividing net income available to common shareholders by the weighted-average number of common shares outstanding during the period. Diluted earnings per common share is calculated by dividing net income available to common shareholders by the weighted-average number of common shares outstanding during the period, plus the effect of outstanding stock options and stock performance awards if dilutive. Refer to Note 16 for additional information
Fair Value of Financial Instruments, Policy [Policy Text Block]	FAIR VALUE MEASUREMENTS Fair value guidance establishes a framework for using fair value to measure assets and liabilities and defines fair value as the price that would be received to sell an asset or paid to transfer a liability (an exit price) as opposed to the price that would be paid to acquire the asset or received to assume the liability (an entry price). A fair value measure should reflect the assumptions that market participants would use in pricing the asset or liability, including the assumptions about the risk inherent in a particular valuation technique, the effect of a restriction on the sale or use of an asset and the risk of nonperformance. Required disclosures include stratification of balance sheet amounts measured at fair value based on inputs the Company uses to derive fair value measurements. These strata include: • Level 1 valuations, where the valuation is based on quoted market prices for identical assets or liabilities traded in active markets (which include exchanges and over-the-counter markets with sufficient volume), • Level 2 valuations, where the valuation is based on quoted market prices for similar instruments traded in active markets, quoted prices for identical or similar instruments in markets that are not active and model-based valuation techniques for which all significant assumptions are observable in the market, and • Level 3 valuations, where the valuation is generated from model-based techniques that use significant assumptions not observable in the market, but observable based on Company-specific data. These unobservable assumptions reflect the Company’s own estimates for assumptions that market participants would use in pricing the asset or liability. Valuation techniques typically include option pricing models, discounted cash flow models and similar techniques, but may also include the use of market prices of assets or liabilities that are not directly comparable to the subject asset or liability. ITEMS MEASURED AT FAIR VALUE ON A RECURRING BASIS Trading account securities, securities available for sale, certain mortgage loans held for sale, residential MSRs, derivative assets and derivative liabilities are recorded at fair value on a recurring basis. Below is a description of valuation methodologies for these assets and liabilities. Trading account securities and securities available for sale consist of U.S. Treasuries, obligations of states and political subdivisions, mortgage-backed securities (including agency securities), other debt securities and equity securities. • U.S. Treasuries are valued based on quoted market prices of identical assets on active exchanges. Pricing received for U.S. Treasuries from third-party services is based on a market approach using dealer quotes from multiple active market makers and real-time trading systems. These valuations are Level 1 measurements. • Mortgage-backed securities are valued primarily using data from third-party pricing services for similar securities as applicable. Pricing from these third-party services is generally based on a market approach using observable inputs such as benchmark yields, reported trades, broker/dealer quotes, benchmark securities, TBA prices, issuer spreads, bids and offers, monthly payment information, and collateral performance, as applicable. These valuations are Level 2 measurements. Where such comparable data is not available, the Company develops valuations based on assumptions that are not readily observable in the market place; these valuations are Level 3 measurements. • Obligations of states and political subdivisions are generally based on data from third-party pricing services. The valuations are based on a market approach using observable inputs such as benchmark yields, MSRB reported trades, material event notices and new issue data. These valuations are Level 2 measurements. Where such comparable data is not available, the Company develops valuations based on assumptions that are not readily observable in the market place; these valuations are Level 3 measurements. • Other debt securities are valued based on Level 1, 2 and 3 measurements, depending on pricing methodology selected and are valued primarily using data from third-party pricing services. Pricing from these third-party services is generally based on a market approach using observable inputs such as benchmark yields, reported trades, broker/dealer quotes, issuer spreads, benchmark securities, bids and offers, and TRACE reported trades. • Marketable equity securities are valued based on quoted market prices of identical assets on active exchanges; these valuations are Level 1 measurements. Regions’ trading account securities and the majority of securities available for sale are valued using third-party pricing services. To validate pricing related to investment securities held in the trading account securities portfolios, pricing received from third-party pricing services is compared to available market data for reasonableness and/or pricing information from other third-party pricing services. To validate pricing related to liquid investment securities, which represent the vast majority of the available for sale portfolio (e.g., mortgage-backed securities), Regions compares price changes received from the third-party pricing service to overall changes in market factors in order to validate the pricing received. To validate pricing received on less liquid investment securities in the available for sale portfolio, Regions receives pricing from third-party brokers/dealers on a sample of securities that are then compared to the pricing received. The pricing service uses standard observable inputs when available, for example: benchmark yields, reported trades, broker-dealer quotes, issuer spreads, benchmark securities, and bids and offers, among others. For certain security types, additional inputs may be used, or some inputs may not be applicable. It is not customary for Regions to adjust the pricing received for the available for sale portfolio. In the event that prices are adjusted, Regions classifies the measurement as a Level 3 measurement. Mortgage loans held for sale consist of residential first mortgage loans and commercial mortgages held for sale. Regions has elected to measure certain residential and commercial mortgage loans held for sale at fair value by applying the fair value option (see additional discussion under the “Fair Value Option” section in Note 22). The residential first mortgage loans held for sale are valued based on traded market prices of similar assets where available and/or discounted cash flows at market interest rates, adjusted for securitization activities that include servicing value and market conditions, a Level 2 measurement. The commercial mortgage loans held for sale are valued based on traded market prices for comparable commercial mortgage-backed securitizations, into which the loans will be placed, adjusted for movements of interest rates and credit spreads, a Level 3 measurement due to the unobservable inputs included in the credit spreads for bonds in commercial mortgage-backed securitizations. Residential mortgage servicing rights are valued using an option-adjusted spread valuation approach, a Level 3 measurement. The underlying assumptions and estimated values are corroborated at least quarterly by values received from independent third parties. See Note 7 for information regarding the servicing of financial assets and additional details regarding the assumptions relevant to this valuation. Derivative assets and liabilities, which primarily consist of interest rate, foreign exchange, and commodity contracts that include forwards, futures, options and swaps, are included in other assets and other liabilities (as applicable) on the consolidated balance sheets. Interest rate swaps are predominantly traded in over-the-counter markets and, as such, values are determined using widely accepted discounted cash flow models, which are Level 2 measurements. These discounted cash flow models use projections of future cash payments/receipts that are discounted at an appropriate index rate. Regions utilizes OIS curves as fair value measurement inputs for the valuation of interest rate and commodity derivatives. The projected future cash flows are sourced from an assumed yield curve, which is consistent with industry standards and conventions. These valuations are adjusted for the unsecured credit risk at the reporting date, which considers collateral posted and the impact of master netting agreements. For options and futures contracts traded in over-the-counter markets, values are determined using discounted cash flow analyses and option pricing models based on market rates and volatilities, which are Level 2 measurements. Interest rate lock commitments on loans intended for sale and risk participations categorized as credit derivatives are valued using option pricing models that incorporate significant unobservable inputs, and therefore are Level 3 measurements. ITEMS MEASURED AT FAIR VALUE ON A NON-RECURRING BASIS From time to time, certain assets may be recorded at fair value on a non-recurring basis. These non-recurring fair value adjustments typically are a result of the application of lower of cost or fair value accounting or a write-down occurring during the period. For example, if the fair value of an asset in these categories falls below its cost basis, it is considered to be at fair value at the end of the period of the adjustment. In periods where there is no adjustment, the asset is generally not considered to be at fair value. The following is a description of the valuation methodologies used for assets measured at fair value on a non-recurring basis. Foreclosed property and other real estate is carried in other assets at the lower of the recorded investment in the loan or fair value less estimated costs to sell the property. The fair value for foreclosed property that is based on either observable transactions of similar instruments or formally committed sale prices is classified as a Level 2 measurement. If no formally committed sale price is available, Regions also obtains valuations from professional valuation experts and/or third party appraisers. Updated valuations are obtained on at least an annual basis. Foreclosed property exceeding established dollar thresholds is valued based on appraisals. Appraisals are performed by third-parties with appropriate professional certifications and conform to generally accepted appraisal standards as evidenced by the Uniform Standards of Professional Appraisal Practice. Regions’ policies related to appraisals conform to regulations established by the Financial Institutions Reform, Recovery and Enforcement Act of 1989 and other regulatory guidance. Professional valuations are considered Level 2 measurements because they are based largely on observable inputs. Regions has a centralized appraisal review function that is responsible for reviewing appraisals for compliance with banking regulations and guidelines as well as appraisal standards. Based on these reviews, Regions may make adjustments to the market value conclusions determined in the appraisals of real estate (either as other real estate or loans held for sale) when the appraisal review function determines that the valuation is based on inappropriate assumptions or where the conclusion is not sufficiently supported by the market data presented in the appraisal. Adjustments to the market value conclusions are discussed with the professional valuation experts and/or third-party appraisers; the magnitude of the adjustments that are not mutually agreed upon is insignificant. In either event, adjustments, if made, must be based on sufficient information available to support an alternate opinion of market value. An estimated standard discount factor, which is updated at least annually, is applied to the appraisal amount for certain commercial and investor real estate properties when the recorded investment in the loan is transferred into foreclosed property. Internally adjusted valuations are considered Level 3 measurements as management uses assumptions that may not be observable in the market. These non-recurring fair value measurements are typically recorded on the date an updated offered quote, appraisal, or third-party valuation is received. Loans held for sale for which the fair value option has not been elected are recorded at the lower of cost or fair value and therefore may be reported at fair value on a non-recurring basis. The fair values for commercial loans held for sale that are based on formally committed loan sale prices or valuations performed using observable inputs are classified as a Level 2 measurement. If no formally committed sales price is available, a professional valuation is obtained, consistent with the process described above for foreclosed property and other real estate. FAIR VALUE OF FINANCIAL INSTRUMENTS The following methods and assumptions were used by the Company in estimating fair values of financial instruments that are not disclosed above: Cash and cash equivalents : The carrying amounts reported in the consolidated balance sheets and cash flows approximate the estimated fair values. Because these amounts generally relate to either currency or highly liquid assets, these are considered Level 1 valuations. Securities held to maturity : The fair values of securities held to maturity are estimated in the same manner as the corresponding securities available for sale, which are measured at fair value on a recurring basis. Loans, (excluding capital leases), net of unearned income and allowance for loan losses : A discounted cash flow method under the income approach is utilized to estimate the fair value of the loan portfolio. The discounted cash flow method relies upon assumptions about the amount and timing of scheduled principal and interest payments, principal prepayments, and adjusted market interest rates. The loan portfolio is aggregated into categories based on loan type and credit quality. For each loan category, weighted average statistics, such as coupon rate, age, and remaining term are calculated. These are Level 3 valuations. Other earning assets (excluding operating leases) : The carrying amounts reported in the consolidated balance sheets approximate the estimated fair values. While these instruments are not actively traded in the market, the majority of the inputs required to value them are actively quoted and can be validated through external sources. Accordingly, these are Level 2 valuations. Deposits : The fair value of non-interest-bearing demand accounts, interest-bearing transaction accounts, savings accounts, money market accounts and certain other time deposit accounts is the amount payable on demand at the reporting date (i.e., the carrying amount). Fair values for certificates of deposit are estimated by using discounted cash flow analyses, based on market spreads to benchmark rates. These are Level 2 valuations. Short-term and long-term borrowings : The carrying amounts of short-term borrowings reported in the consolidated balance sheets approximate the estimated fair values, and are considered Level 2 measurements as similar instruments are traded in active markets. The fair values of certain long-term borrowings are estimated using quoted market prices of identical instruments in active markets and are considered Level 1 measurements. The fair values of certain long term borrowings are estimated using quoted market prices of identical instruments in non-active markets and are considered Level 2 valuations. Otherwise, valuations are based on non-binding broker quotes and are considered Level 3 valuations. Loan commitments and letters of credit : The estimated fair values for these off-balance sheet instruments are based on probabilities of funding to project future loan fundings, which are discounted using the loan methodology described above. The premiums/discounts are adjusted for the time value of money over the average remaining life of the commitments and the opportunity cost associated with regulatory requirements. Because the probabilities of funding and loan valuations are not observable in the market and are considered Company specific inputs, these are Level 3 valuations. See Note 22 for additional information related to fair value measurements
New Accounting Pronouncements, Policy [Policy Text Block]	RECENT ACCOUNTING PRONOUNCEMENTS AND ACCOUNTING CHANGES The following table provides a brief description of accounting standards that could have a material impact to Regions’ consolidated financial statements upon adoption. Standard Description Required Date of Adoption Effect on Regions' financial statements or other significant matters Standards Adopted (or partially adopted) in 2017 ASU 2016-05, Effect of Derivative Contract Novations on Existing Hedge Accounting Relationships The ASU amends Topic 815, Derivatives and Hedging, and addresses how a change in the counterparty to a derivative contract affects a hedging relationship. The ASU may be adopted either prospectively or on a modified retrospective basis. January 1, 2017 The adoption of this guidance did not have a material impact. ASU 2016-06, Contingent Put and Call Options in Debt Instruments The ASU amends Topic 815, Derivatives and Hedging, and clarifies that entities should solely use the four-step decision sequence described in current derivatives accounting guidance. This sequence should be used when assessing whether contingent exercise provisions associated with a put or call option are clearly and closely related to their debt hosts. The ASU should be adopted on a modified retrospective basis. January 1, 2017 The adoption of this guidance did not have a material impact. ASU 2016-07, Simplifying the Transition to the Equity Method of Accounting The ASU amends Topic 323, Investments- Equity Method and Joint Ventures, and eliminates the requirement for an investor to retrospectively apply the equity method to investments when its ownership interest (or degree of influence in an investee) increases to a level that triggers the equity method of accounting. This ASU should be adopted prospectively. January 1, 2017 The adoption of this guidance did not have a material impact. ASU 2016-09, Improvements to Employee Share-Based Payment Accounting This ASU amends Topic 718, Stock Compensation, and intends to improve and simplify accounting for employee shared-based payments. The amendments update the accounting for income taxes, forfeitures, and statutory tax withholding requirements, as well as classification in the statement of cash flows. The transition method of accounting application (i.e. prospective, retrospective or modified retrospective application) differs by amendment and is defined in the guidance. January 1, 2017 The adoption of this guidance did not have a material impact related to the reclassification of excess tax benefits previously recognized in additional paid-in capital to income tax expense (prospective basis), cash flow statement reclassification related to excess tax benefits (prospective basis) or cash flow statement reclassification related to taxes paid for employee withholdings on share-based awards (retrospective basis). Additionally, the Company has no previously unrecognized excess tax benefits; therefore, there was no impact. The Company elected to retain its existing accounting policy election to estimate award forfeitures. ASU 2016-17, Interest Held through Related Parties That Are Under Common Control This ASU amends Topic 810, Consolidation, and prescribes that when determining whether a single decision maker is the primary beneficiary of a variable interest entity (VIE), a single decision maker will no longer be required to consider indirect interests held through related parties that are under common control with the single decision maker to be the equivalent of direct interests in their entirety. January 1, 2017 The adoption of this guidance did not have a material impact. ASU 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income The ASU amends Topic 220, Income Statement-Reporting Comprehensive Income, and is intended to help organizations reclassify certain stranded income tax effects in accumulated other comprehensive income resulting from the recently enacted Tax Reform. The guidance allows entities to reclassify stranded tax effects in accumulated other comprehensive income to retained earnings. January 1, 2019, with early adoption permitted for financial statements that have not yet been made available for issuance. Regions has elected to adopt this ASU for financial reporting as of December 31, 2017. The effect of the reclassification was to increase retained earnings and decrease accumulated other comprehensive income by $133 million, with zero net effect on total stockholders’ equity. Standard Description Required Date of Adoption Effect on Regions' financial statements or other significant matters Standards Not Yet Adopted ASU 2014-09, Revenue from Contracts with Customers This ASU supersedes the revenue recognition requirements in ASC Topic 605, Revenue Recognition, and most industry-specific guidance throughout the Industry topics of the Codification. The core principle of the ASU is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The ASU may be adopted either retrospectively or on a modified retrospective basis. January 1, 2018 Regions established a revenue recognition standard implementation team, led by the Corporate Controller’s group with assistance from the various lines of business and finance management to evaluate the potential impact of adopting this guidance. The implementation team determined that approximately $1.6 billion of 2016 non-interest income would be within the scope of the new revenue recognition standard, when adopted. Income streams that are out of scope of the new standard include interest income, mortgage income, securities gains (losses), bank-owned life insurance and certain other components within non-interest income. The implementation team completed its reviews of contracts related to in-scope non-interest income in 2017. Changes in revenue recognition for those in-scope contracts will not have a material impact to Regions upon adoption. The implementation team has developed additional quantitative and qualitative disclosures required by the new revenue recognition standard. ASU 2016-15, Classification of Certain Cash Receipts and Cash Payments This ASU amends Topic 230, Statement of Cash Flows, and provides clarification with respect to classification within the statement of cash flows where current guidance is unclear or silent. The ASU should be adopted retrospectively. January 1, 2018 Regions believes the adoption of this guidance will not have a material impact. ASU 2017-01, Clarifying the Definition of a Business This ASU amends Topic 805, Business Combinations, and provides additional accounting guidance to better determine when a set of assets and activities is a business. The ASU should be adopted prospectively. January 1, 2018 Regions believes the adoption of this guidance will not have a material impact. ASU 2017-04, Simplifying the Test for Goodwill Impairment This ASU amends Topic 350, Intangibles-Goodwill and Other, and eliminates Step 2 from the goodwill impairment test. January 1, 2020 Regions believes the adoption of this guidance will not have a material impact. Regions does not plan to early adopt. ASU 2017-05, Other Income- Gains and Losses from the Derecognition of Nonfinancial Assets This ASU amends Subtopic 610-20, Other Income - Gains and Losses from the Derecognition of Nonfinancial Assets, to clarify the scope and to add guidance for partial sales of nonfinancial assets. The new standard adds a definition for in-substance nonfinancial assets and clarifies that nonfinancial assets within a legal entity are within the scope of ASC 606. This ASU should be adopted in conjunction with ASU 2014-09 using a retrospective or modified retrospective approach. January 1, 2018 Regions believes the adoption of this guidance will not have a material impact. ASU 2017-07, Compensation- Retirement Benefits This ASU amends Topic 715, Retirement Benefits, and provides more prescriptive guidance around the presentation of net period pension and postretirement benefit cost in the income statement. The amendment requires that the service cost component be disaggregated from other components of net periodic benefit cost in the income statement. January 1, 2018 Regions estimates that a benefit or reduction in certain components of net periodic pension (benefit) cost of approximately $35 - $40 million will be reclassified out of salaries and employee benefits and into other non-interest expense during 2018. Prior periods will also include similar reclassifications. ASU 2017-08, Receivables- Nonrefundable Fees and Other Costs This ASU amends Subtopic 310-20, Receivables-Nonrefundable Fees and Other Costs, to shorten the amortization period for certain purchased callable debt securities held at a premium to the earliest call date. Current guidance generally requires entities to amortize a premium as a yield adjustment over the contractual life of the instrument. Shortening the amortization period is generally expected to more closely align the recognition of interest income with expectations incorporated into the pricing of the underlying securities. The amendments do not affect the accounting treatment of discounts. This ASU should be adopted on a modified retrospective basis. January 1, 2019 Regions is evaluating the impact upon adoption; however, the impact is not expected to be material. Standard Description Required Date of Adoption Effect on Regions' financial statements or other significant matters Standards Not Yet Adopted (continued) ASU 2016-02, Leases This ASU creates ASU Topic 842, Leases, and supersedes Topic 840, Leases. The new guidance requires lessees to record a right-of-use asset and a corresponding liability equal to the present value of future rental payments on their balance sheets for all leases with a term greater than one year. There are not significant changes to lessor accounting; however, there are certain improvements made to align lessor accounting with the lessee accounting model and Topic 606, Revenue from Contracts with Customers. This guidance expands both quantitative and qualitative required disclosures. This ASU should be adopted on a modified retrospective basis. January 1, 2019 This ASU supersedes the lease accounting requirements in Topic 840, Leases. Regions has established a leasing standard implementation team comprised of the Corporate Controller’s group, Corporate Real Estate and other business and finance management to plan and execute the adoption of the new leasing standard. The implementation team has substantially completed the identification of Regions’ leases that will need to be measured and reported as a right-of-use asset and corresponding liability for future rental payments. The implementation team is currently working with a lease administration vendor to set up and test the accounting for the lease contracts on the lease administration system. Based on preliminary estimates that are subject to change, Regions has a range of approximately $400-$700 million of future lease obligations that would be measured and recognized when the new guidance is adopted. While this amount represents a large majority of the leases that are within the scope of the new leasing standard, the implementation team will continue reviewing service contracts up through the effective date and may identify additional leases embedded in those arrangements that will be within the scope of the new standard. Between now and January 1, 2019, Regions will likely have changes to the lease portfolio as the Company continues to evaluate and execute branch and occupancy optimization initiatives. In addition to final determination of the lease portfolio at the effective date, the initial measurement of the right-of-use asset and the corresponding liability will be affected by certain key assumptions such as expectations of renewals or extensions and the interest rate to be used to discount the future lease obligations. Up through the date of adoption, the evaluation of the impact of the standard will be adjusted based on new leases that are executed, leases that are terminated prior to the effective date, and any leases with changes to key assumptions or expectations such as renewals and extensions, and discount rates. While there will be some changes to income statement classification, the implementation team does not expect the adoption of the standard to have a material impact to pre-tax income. Regions does not anticipate early adoption of the new standard. ASU 2016-13, Measurement of Credit Losses on Financial Instruments This ASU amends Topic 326, Financial Instruments- Credit Losses to replace the current incurred loss accounting model with a current expected credit loss approach (CECL) for financial instruments measured at amortized cost and other commitments to extend credit. The amendments require entities to consider all available relevant information when estimating current expected credit losses, including details about past events, current conditions, and reasonable and supportable forecasts. The resulting allowance for credit losses is to reflect the portion of the amortized cost basis that the entity does not expect to collect. The amendments also eliminate the current accounting model for purchased credit impaired loans and debt securities. Additional quantitative and qualitative disclosures are required upon adoption. January 1, 2020 Regions’ cross-functional implementation team, which is co-led by Finance and Risk Management, has developed a project plan that results in the adoption of the standard in the first quarter of 2020. Key project implementation activities for 2017 focused on understanding the standard, keeping current with the broader industry’s perspective and insights, delivering educational and awareness sessions across the Company, identifying and researching key decision points, designing models, and producing and challenging initial model outputs. During 2018, the focus will be on execution and implementation, continued challenge of model outputs, processes and control, policies, disclosures, and data resolution. Regions expects adoption of the standard will result in an overall increase in the allowance for credit losses given the change from accounting for losses inherent in the loan portfolio to accounting for losses over the remaining expected life of the portfolio. Based on initial modeling, portfolios expected to generate the majority of the increase include longer-dated loans such as residential first mortgages and home equity lending products. Additionally, there could be decreases in the allowance in certain of our loan portfolios at adoption. The guidance will also result in the establishment of an allowance for credit loss on held to maturity debt securities. The amount of the change in these allowances will be impacted by the portfolio composition and quality at the adoption date as well as economic conditions and forecasts at that time. ASU 2017-12, Targeted Improvements to Accounting for Hedging Activities This ASU amends ASC 815, Derivatives and Hedging to (1) improve the transparency and understandability of information conveyed to financial statement users about an entity’s risk management activities by better aligning the entity’s financial reporting for hedging relationships with those risk management activities and (2) reduce the complexity of and simplify the application of hedge accounting by preparers. January 1, 2019 Regions is evaluating the impact upon adoption; however, the impact is not expected to be material. Regions is considering early adoption. Standard Description Required Date of Adoption Effect on Regions' financial statements or other significant matters Standards Not Yet Adopted (continued) ASU 2016-01, Recognition and Measurement of Financial Assets and Liabilities This ASU amends ASC Topic 825, Financial Instruments-Overall, and addresses certain aspects of recognition, measurement, presentation, and disclosure of financial instruments. Among other minor amendments applicable to Regions, the main provisions require investments in equity securities to be measured at fair value with changes in fair value recognized through net income unless they qualify for a practicability exception (excludes investments accounted for under the equity method of accounting or those that result in consolidation of the investee). Except for disclosure requirements that will be adopted prospectively, the ASU must be adopted on a modified retrospective basis. January 1, 2018 Regions believes the adoption of this guidance will not have a material impact. ASU 2017-09, Stock Compensation: Scope of Modification Accounting This ASU amends Topic 718, Compensation- Stock Compensation, and clarifies when modification accounting should be applied to changes in terms or conditions of share-based payment awards. The amendments narrow the scope of modification accounting by clarifying that modification accounting should be applied to awards if the change affects the fair value, vesting conditions, or classification of the award. The amendments do not impact current disclosure requirements for modifications, regardless of whether modification accounting is required under the new guidance. January 1, 2018 Regions believes the adoption of this guidance will not have a material impact.

Summary of Significant Accoun36

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Cash Flow, Supplemental Disclosures [Text Block]	The following table summarizes supplemental cash flow information for the years ended December 31 : 2017 2016 2015 (In millions) Cash paid during the period for: Interest on deposits and borrowings $ 363 $ 299 $ 268 Income taxes, net 181 314 129 Non-cash transfers: Operating leases transferred from loans — — 879 Loans held for sale and loans transferred to other real estate 80 100 156 Loans transferred to loans held for sale 41 247 69 Loans held for sale transferred to loans 8 5 3 Properties transferred to held for sale 33 53 38 Loans settled with trading account securities 33 — — Operating lease assets settled with trading account securities 15 — —

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	12 Months Ended
	Dec. 31, 2017
Disclosure Variable Interest Entities Schedule Of Equity Method Investments [Abstract]
Equity Method Investments	A summary of Regions’ proportional amortization method investments, equity method investments and related loans and letters of credit, representing Regions’ maximum exposure to loss as of December 31 is as follows: 2017 2016 (In millions) Proportional amortization method investments included in other assets $ 1,144 $ 1,013 Equity method investments included in other assets 20 21 Unfunded commitments included in other liabilities 348 301 Short-term construction loans and letters of credit commitments 317 249 Funded portion of short-term loans and letters of credit 129 103

Discontinued Operations (Tables

Discontinued Operations (Tables)	12 Months Ended
	Dec. 31, 2017
Discontinued Operations and Disposal Groups [Abstract]
Schedule of Condensed Results of Operations for Discontinued Operations	The following table represents the condensed results of operations for discontinued operations: Year Ended December 31 2017 2016 2015 (In millions, except per share data) Non-interest expense: Professional and legal expenses/(recoveries) $ (10 ) $ (9 ) $ 21 Other 2 1 1 Total non-interest expense (8 ) (8 ) 22 Income (loss) from discontinued operations before income taxes 8 8 (22 ) Income tax expense (benefit) 2 3 (9 ) Income (loss) from discontinued operations, net of tax $ 6 $ 5 $ (13 ) Earnings (loss) per common share from discontinued operations: Basic $ 0.01 $ 0.00 $ (0.01 ) Diluted $ 0.00 $ 0.00 $ (0.01 )

Securities (Tables)

Securities (Tables)	12 Months Ended
	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Schedule Of Amortized Cost, Gross Unrealized Gains And Losses, And Estimated Fair Value Of Securities Available For Sale And Securities Held To Maturity	The amortized cost, gross unrealized gains and losses, and estimated fair value of securities held to maturity and securities available for sale are as follows: December 31, 2017 Recognized in OCI (1) Not recognized in OCI Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Carrying Value Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (In millions) Securities held to maturity: Mortgage-backed securities: Residential agency $ 1,051 $ — $ (40 ) $ 1,011 $ 12 $ (4 ) $ 1,019 Commercial agency 651 — (4 ) 647 5 (4 ) 648 $ 1,702 $ — $ (44 ) $ 1,658 $ 17 $ (8 ) $ 1,667 Securities available for sale: U.S. Treasury securities $ 333 $ — $ (2 ) $ 331 $ 331 Federal agency securities 28 — — 28 28 Mortgage-backed securities: Residential agency 17,622 53 (244 ) 17,431 17,431 Residential non-agency 3 — — 3 3 Commercial agency 3,739 5 (30 ) 3,714 3,714 Commercial non-agency 787 4 (3 ) 788 788 Corporate and other debt securities 1,093 20 (5 ) 1,108 1,108 Equity securities 225 — — 225 225 $ 23,830 $ 82 $ (284 ) $ 23,628 $ 23,628 December 31, 2016 Recognized in OCI (1) Not recognized in OCI Amortized Gross Unrealized Gains Gross Unrealized Losses Carrying Value Gross Gross Estimated (In millions) Securities held to maturity: Mortgage-backed securities: Residential agency $ 1,249 $ — $ (49 ) $ 1,200 $ 12 $ (3 ) $ 1,209 Commercial agency 167 — (5 ) 162 — (2 ) 160 $ 1,416 $ — $ (54 ) $ 1,362 $ 12 $ (5 ) $ 1,369 Securities available for sale: U.S. Treasury securities $ 303 $ 1 $ (1 ) $ 303 $ 303 Federal agency securities 35 — — 35 35 Obligations of states and political subdivisions 1 — — 1 1 Mortgage-backed securities: Residential agency 17,531 95 (255 ) 17,371 17,371 Residential non-agency 4 — — 4 4 Commercial agency 3,486 9 (32 ) 3,463 3,463 Commercial non-agency 1,124 8 (3 ) 1,129 1,129 Corporate and other debt securities 1,272 19 (17 ) 1,274 1,274 Equity securities 194 7 — 201 201 $ 23,950 $ 139 $ (308 ) $ 23,781 $ 23,781 _________ (1) The gross unrealized losses recognized in OCI on held to maturity securities resulted from a transfer of available for sale securities to held to maturity in the second quarter of 2013.
Schedule Of Cost And Estimated Fair Value Of Securities Available For Sale And Securities Held To Maturity By Contractual Maturity	The amortized cost and estimated fair value of securities held to maturity and securities available for sale at December 31, 2017 , by contractual maturity, are shown below. 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. Amortized Cost Estimated Fair Value (In millions) Securities held to maturity: Mortgage-backed securities: Residential agency $ 1,051 $ 1,019 Commercial agency 651 648 $ 1,702 $ 1,667 Securities available for sale: Due in one year or less $ 33 $ 33 Due after one year through five years 876 878 Due after five years through ten years 462 471 Due after ten years 83 85 Mortgage-backed securities: Residential agency 17,622 17,431 Residential non-agency 3 3 Commercial agency 3,739 3,714 Commercial non-agency 787 788 Equity securities 225 225 $ 23,830 $ 23,628
Schedule Of Gross Unrealized Losses And Estimated Fair Value Of Securities Available For Sale and Held To Maturity	The following tables present gross unrealized losses and the related estimated fair value of securities held to maturity and securities available for sale at December 31, 2017 and 2016 . For securities transferred to held to maturity from available for sale, the analysis in the tables below is comparing the securities' original amortized cost to its current estimated fair value. These securities are segregated between investments that have been in a continuous unrealized loss position for less than twelve months and for twelve months or more. December 31, 2017 Less Than Twelve Months Twelve Months or More Total Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses (In millions) Securities held to maturity: Mortgage-backed securities: Residential agency $ — $ — $ 1,019 $ (32 ) $ 1,019 $ (32 ) Commercial agency — — 150 (7 ) 150 (7 ) $ — $ — $ 1,169 $ (39 ) $ 1,169 $ (39 ) Securities available for sale: U.S. Treasury securities $ 221 $ (1 ) $ 84 $ (1 ) $ 305 $ (2 ) Mortgage-backed securities: Residential agency 5,157 (40 ) 8,195 (204 ) 13,352 (244 ) Commercial agency 1,666 (10 ) 904 (20 ) 2,570 (30 ) Commercial non-agency 393 (2 ) 61 (1 ) 454 (3 ) All other securities 330 (2 ) 105 (3 ) 435 (5 ) $ 7,767 $ (55 ) $ 9,349 $ (229 ) $ 17,116 $ (284 ) December 31, 2016 Less Than Twelve Months Twelve Months or More Total Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses (In millions) Securities held to maturity: Mortgage-backed securities: Residential agency $ 850 $ (26 ) $ 359 $ (14 ) $ 1,209 $ (40 ) Commercial agency — — 160 (7 ) 160 (7 ) $ 850 $ (26 ) $ 519 $ (21 ) $ 1,369 $ (47 ) Securities available for sale: U.S. Treasury securities $ 112 $ (1 ) $ 18 $ — $ 130 $ (1 ) Mortgage-backed securities: Residential agency 12,071 (245 ) 570 (10 ) 12,641 (255 ) Commercial agency 2,199 (31 ) 45 (1 ) 2,244 (32 ) Commercial non-agency 402 (2 ) 176 (1 ) 578 (3 ) All other securities 382 (6 ) 218 (11 ) 600 (17 ) $ 15,166 $ (285 ) $ 1,027 $ (23 ) $ 16,193 $ (308 )
Schedule Of Gross Realized Gains And Gross Realized Losses On Available For Sale Securities	Gross realized gains and gross realized losses on sales of securities available for sale, as well as OTTI losses, for years ended December 31 are shown in the table below. The cost of securities sold is based on the specific identification method. 2017 2016 2015 (In millions) Gross realized gains $ 25 $ 36 $ 44 Gross realized losses (5 ) (28 ) (8 ) OTTI (1 ) (2 ) (7 ) Securities available for sale gains, net (1) $ 19 $ 6 $ 29 _________ (1) The securities gains (losses), net balances above exclude net trading securities gains of $3 million recognized during 2017.

Loans (Tables)

Loans (Tables)	12 Months Ended
	Dec. 31, 2017
Receivables [Abstract]
Schedule Of Loan Portfolio, Net Of Unearned Income	The following table presents the distribution of Regions' loan portfolio by segment and class, net of unearned income as of December 31 : 2017 2016 (In millions) Commercial and industrial $ 36,115 $ 35,012 Commercial real estate mortgage—owner-occupied 6,193 6,867 Commercial real estate construction—owner-occupied 332 334 Total commercial 42,640 42,213 Commercial investor real estate mortgage 4,062 4,087 Commercial investor real estate construction 1,772 2,387 Total investor real estate 5,834 6,474 Residential first mortgage 14,061 13,440 Home equity 10,164 10,687 Indirect—vehicles 3,326 4,040 Indirect—other consumer 1,467 920 Consumer credit card 1,290 1,196 Other consumer 1,165 1,125 Total consumer 31,473 31,408 Total loans, net of unearned income (1) $ 79,947 $ 80,095 _________ (1) Loans are presented net of unearned income, unamortized discounts and premiums and net deferred loan costs of $43 million and $141 million at December 31, 2017 and 2016 , respectively.
Regions' Investment In Leveraged Leases Included Within Commercial And Industrial Loans	The following tables include details regarding Regions’ investment in leveraged leases included within the commercial and industrial loan portfolio class as of and for the years ended December 31 : 2017 2016 (In millions) Rentals receivable $ 248 $ 303 Estimated residuals on leveraged leases 196 203 Unearned income on leveraged leases 160 184 2017 2016 2015 (In millions) Pre-tax income from leveraged leases $ 22 $ 28 $ 34 Income tax expense on income from leveraged leases 24 31 33

Allowance for Credit Losses (Ta

Allowance for Credit Losses (Tables)	12 Months Ended
	Dec. 31, 2017
Receivables [Abstract]
Analysis Of The Allowance For Credit Losses By Portfolio Segment	2017 Commercial Investor Real Estate Consumer Total (In millions) Allowance for loan losses, January 1, 2017 $ 753 $ 85 $ 253 $ 1,091 Provision (credit) for loan losses (28 ) (42 ) 220 150 Loan losses: Charge-offs (176 ) (2 ) (256 ) (434 ) Recoveries 42 23 62 127 Net loan losses (134 ) 21 (194 ) (307 ) Allowance for loan losses, December 31, 2017 591 64 279 934 Reserve for unfunded credit commitments, January 1, 2017 64 5 — 69 Provision (credit) for unfunded credit losses (15 ) (1 ) — (16 ) Reserve for unfunded credit commitments, December 31, 2017 49 4 — 53 Allowance for credit losses, December 31, 2017 $ 640 $ 68 $ 279 $ 987 Portion of ending allowance for loan losses: Individually evaluated for impairment $ 171 $ 8 $ 47 $ 226 Collectively evaluated for impairment 420 56 232 708 Total allowance for loan losses $ 591 $ 64 $ 279 $ 934 Portion of loan portfolio ending balance: Individually evaluated for impairment $ 756 $ 96 $ 706 $ 1,558 Collectively evaluated for impairment 41,884 5,738 30,767 78,389 Total loans evaluated for impairment $ 42,640 $ 5,834 $ 31,473 $ 79,947 2016 Commercial Investor Real Estate Consumer Total (In millions) Allowance for loan losses, January 1, 2016 $ 758 $ 97 $ 251 $ 1,106 Provision (credit) for loan losses 95 (23 ) 190 262 Loan losses: Charge-offs (143 ) (2 ) (253 ) (398 ) Recoveries 43 13 65 121 Net loan losses (100 ) 11 (188 ) (277 ) Allowance for loan losses, December 31, 2016 753 85 253 1,091 Reserve for unfunded credit commitments, January 1, 2016 47 5 — 52 Provision (credit) for unfunded credit losses 17 — — 17 Reserve for unfunded credit commitments, December 31, 2016 64 5 — 69 Allowance for credit losses, December 31, 2016 $ 817 $ 90 $ 253 $ 1,160 Portion of ending allowance for loan losses: Individually evaluated for impairment $ 231 $ 13 $ 60 $ 304 Collectively evaluated for impairment 522 72 193 787 Total allowance for loan losses $ 753 $ 85 $ 253 $ 1,091 Portion of loan portfolio ending balance: Individually evaluated for impairment $ 1,069 $ 107 $ 770 $ 1,946 Collectively evaluated for impairment 41,144 6,367 30,638 78,149 Total loans evaluated for impairment $ 42,213 $ 6,474 $ 31,408 $ 80,095 2015 Commercial Investor Real Estate Consumer Total (In millions) Allowance for loan losses, January 1, 2015 $ 654 $ 150 $ 299 $ 1,103 Provision (credit) for loan losses 191 (65 ) 115 241 Loan losses: Charge-offs (154 ) (15 ) (234 ) (403 ) Recoveries 67 27 71 165 Net loan losses (87 ) 12 (163 ) (238 ) Allowance for loan losses, December 31, 2015 758 97 251 1,106 Reserve for unfunded credit commitments, January 1, 2015 57 8 — 65 Provision (credit) for unfunded credit losses (10 ) (3 ) — (13 ) Reserve for unfunded credit commitments, December 31, 2015 47 5 — 52 Allowance for credit losses, December 31, 2015 $ 805 $ 102 $ 251 $ 1,158 Portion of ending allowance for loan losses: Individually evaluated for impairment $ 189 $ 26 $ 68 $ 283 Collectively evaluated for impairment 569 71 183 823 Total allowance for loan losses $ 758 $ 97 $ 251 $ 1,106 Portion of loan portfolio ending balance: Individually evaluated for impairment $ 743 $ 191 $ 835 $ 1,769 Collectively evaluated for impairment 43,039 6,756 29,598 79,393 Total loans evaluated for impairment $ 43,782 $ 6,947 $ 30,433 $ 81,162
Credit Quality Indicators Excluding Loans Held For Sale	The following tables present credit quality indicators for the loan portfolio segments and classes, excluding loans held for sale, as of December 31, 2017 and 2016 . 2017 Pass Special Mention Substandard Accrual Non-accrual Total (In millions) Commercial and industrial $ 34,420 $ 686 $ 605 $ 404 $ 36,115 Commercial real estate mortgage—owner-occupied 5,674 236 165 118 6,193 Commercial real estate construction—owner-occupied 313 3 10 6 332 Total commercial $ 40,407 $ 925 $ 780 $ 528 $ 42,640 Commercial investor real estate mortgage $ 3,905 $ 63 $ 89 $ 5 $ 4,062 Commercial investor real estate construction 1,706 19 46 1 1,772 Total investor real estate $ 5,611 $ 82 $ 135 $ 6 $ 5,834 Accrual Non-accrual Total (In millions) Residential first mortgage $ 14,014 $ 47 $ 14,061 Home equity 10,095 69 10,164 Indirect—vehicles 3,326 — 3,326 Indirect—other consumer 1,467 — 1,467 Consumer credit card 1,290 — 1,290 Other consumer 1,165 — 1,165 Total consumer $ 31,357 $ 116 $ 31,473 $ 79,947 2016 Pass Special Mention Substandard Accrual Non-accrual Total (In millions) Commercial and industrial $ 32,619 $ 658 $ 1,112 $ 623 $ 35,012 Commercial real estate mortgage—owner-occupied 6,190 221 246 210 6,867 Commercial real estate construction—owner-occupied 308 8 15 3 334 Total commercial $ 39,117 $ 887 $ 1,373 $ 836 $ 42,213 Commercial investor real estate mortgage $ 3,766 $ 190 $ 114 $ 17 $ 4,087 Commercial investor real estate construction 2,192 129 66 — 2,387 Total investor real estate $ 5,958 $ 319 $ 180 $ 17 $ 6,474 Accrual Non-accrual Total (In millions) Residential first mortgage $ 13,390 $ 50 $ 13,440 Home equity 10,595 92 10,687 Indirect—vehicles 4,040 — 4,040 Indirect—other consumer 920 — 920 Consumer credit card 1,196 — 1,196 Other consumer 1,125 — 1,125 Total consumer $ 31,266 $ 142 $ 31,408 $ 80,095
Schedule Of Aging Analysis Of Days Past Due (DPD) For Each Portfolio Class	The following tables include an aging analysis of DPD for each portfolio segment and class as of December 31, 2017 and 2016 : 2017 Accrual Loans 30-59 DPD 60-89 DPD 90+ DPD Total 30+ DPD Total Accrual Non-accrual Total (In millions) Commercial and industrial $ 28 $ 7 $ 4 $ 39 $ 35,711 $ 404 $ 36,115 Commercial real estate mortgage—owner-occupied 18 8 1 27 6,075 118 6,193 Commercial real estate construction—owner-occupied — — — — 326 6 332 Total commercial 46 15 5 66 42,112 528 42,640 Commercial investor real estate mortgage 1 1 1 3 4,057 5 4,062 Commercial investor real estate construction — — — — 1,771 1 1,772 Total investor real estate 1 1 1 3 5,828 6 5,834 Residential first mortgage 95 85 216 396 14,014 47 14,061 Home equity 53 27 37 117 10,095 69 10,164 Indirect—vehicles 48 13 9 70 3,326 — 3,326 Indirect—other consumer 9 5 — 14 1,467 — 1,467 Consumer credit card 11 7 19 37 1,290 — 1,290 Other consumer 13 4 4 21 1,165 — 1,165 Total consumer 229 141 285 655 31,357 116 31,473 $ 276 $ 157 $ 291 $ 724 $ 79,297 $ 650 $ 79,947 2016 Accrual Loans 30-59 DPD 60-89 DPD 90+ DPD Total 30+ DPD Total Accrual Non-accrual Total (In millions) Commercial and industrial $ 59 $ 11 $ 6 $ 76 $ 34,389 $ 623 $ 35,012 Commercial real estate mortgage—owner-occupied 29 7 2 38 6,657 210 6,867 Commercial real estate construction—owner-occupied 1 — — 1 331 3 334 Total commercial 89 18 8 115 41,377 836 42,213 Commercial investor real estate mortgage 6 8 — 14 4,070 17 4,087 Commercial investor real estate construction — — — — 2,387 — 2,387 Total investor real estate 6 8 — 14 6,457 17 6,474 Residential first mortgage 99 63 212 374 13,390 50 13,440 Home equity 60 22 33 115 10,595 92 10,687 Indirect—vehicles 56 14 10 80 4,040 — 4,040 Indirect—other consumer 5 3 — 8 920 — 920 Consumer credit card 9 7 15 31 1,196 — 1,196 Other consumer 13 5 5 23 1,125 — 1,125 Total consumer 242 114 275 631 31,266 142 31,408 $ 337 $ 140 $ 283 $ 760 $ 79,100 $ 995 $ 80,095
Schedule Of Impaired Loans	The following tables present details related to the Company’s impaired loans as of December 31, 2017 and 2016 . Loans deemed to be impaired include all TDRs and all non-accrual commercial and investor real estate loans, excluding leases. Loans which have been fully charged-off do not appear in the tables below. Non-accrual Impaired Loans 2017 Book Value (3) Unpaid Principal Balance (1) Charge-offs and Payments Applied (2) Total Impaired Loans on Non-accrual Status Impaired Loans on Non-accrual Status with No Related Allowance Impaired Loans on Non-accrual Status with Related Allowance Related Allowance for Loan Losses Coverage % (4) (Dollars in millions) Commercial and industrial $ 480 $ 80 $ 400 $ 29 $ 371 $ 103 38.1 % Commercial real estate mortgage—owner-occupied 133 15 118 20 98 38 39.8 Commercial real estate construction—owner-occupied 7 1 6 — 6 3 57.1 Total commercial 620 96 524 49 475 144 38.7 Commercial investor real estate mortgage 6 1 5 — 5 2 50.0 Commercial investor real estate construction 1 — 1 — 1 — — Total investor real estate 7 1 6 — 6 2 42.9 Residential first mortgage 42 11 31 — 31 3 33.3 Home equity 10 1 9 — 9 — 10.0 Total consumer 52 12 40 — 40 3 28.8 $ 679 $ 109 $ 570 $ 49 $ 521 $ 149 38.0 % Accruing Impaired Loans 2017 Book Value (3) Unpaid Principal Balance (1) Charge-offs and Payments Applied (2) Total Impaired Loans on Accrual Status Impaired Loans on Accrual Status with No Related Allowance Impaired Loans on Accrual Status with Related Allowance Related Allowance for Loan Losses Coverage % (4) (Dollars in millions) Commercial and industrial $ 154 $ 8 $ 146 $ 1 $ 145 $ 19 17.5 % Commercial real estate mortgage—owner-occupied 90 5 85 — 85 8 14.4 Commercial real estate construction—owner-occupied 1 — 1 — 1 — — Total commercial 245 13 232 1 231 27 16.3 Commercial investor real estate mortgage 63 2 61 — 61 3 7.9 Commercial investor real estate construction 29 — 29 — 29 3 10.3 Total investor real estate 92 2 90 — 90 6 8.7 Residential first mortgage 419 13 406 — 406 39 12.4 Home equity 251 1 250 — 250 5 2.4 Consumer credit card 1 — 1 — 1 — — Other consumer 9 — 9 — 9 — — Total consumer 680 14 666 — 666 44 8.5 $ 1,017 $ 29 $ 988 $ 1 $ 987 $ 77 10.4 % Total Impaired Loans 2017 Book Value (3) Unpaid Principal Balance (1) Charge-offs and Payments Applied (2) Total Impaired Loans Impaired Loans with No Related Allowance Impaired Loans with Related Allowance Related Allowance for Loan Losses Coverage % (4) (Dollars in millions) Commercial and industrial $ 634 $ 88 $ 546 $ 30 $ 516 $ 122 33.1 % Commercial real estate mortgage—owner-occupied 223 20 203 20 183 46 29.6 Commercial real estate construction—owner-occupied 8 1 7 — 7 3 50.0 Total commercial 865 109 756 50 706 171 32.4 Commercial investor real estate mortgage 69 3 66 — 66 5 11.6 Commercial investor real estate construction 30 — 30 — 30 3 10.0 Total investor real estate 99 3 96 — 96 8 11.1 Residential first mortgage 461 24 437 — 437 42 14.3 Home equity 261 2 259 — 259 5 2.7 Consumer credit card 1 — 1 — 1 — — Other consumer 9 — 9 — 9 — — Total consumer 732 26 706 — 706 47 10.0 $ 1,696 $ 138 $ 1,558 $ 50 $ 1,508 $ 226 21.5 % Non-accrual Impaired Loans 2016 Book Value (3) Unpaid Principal Balance (1) Charge-offs and Payments Applied (2) Total Impaired Loans on Non-accrual Status Impaired Loans on Non-accrual Status with No Related Allowance Impaired Loans on Non-accrual Status with Related Allowance Related Allowance for Loan Losses Coverage % (4) (Dollars in millions) Commercial and industrial $ 685 $ 72 $ 613 $ 126 $ 487 $ 138 30.7 % Commercial real estate mortgage—owner-occupied 231 21 210 39 171 53 32.0 Commercial real estate construction—owner-occupied 4 1 3 — 3 2 75.0 Total commercial 920 94 826 165 661 193 31.2 Commercial investor real estate mortgage 18 1 17 5 12 5 33.3 Total investor real estate 18 1 17 5 12 5 33.3 Residential first mortgage 41 12 29 — 29 4 39.0 Home equity 12 1 11 — 11 — 8.3 Total consumer 53 13 40 — 40 4 32.1 $ 991 $ 108 $ 883 $ 170 $ 713 $ 202 31.3 % Accruing Impaired Loans 2016 Unpaid Principal Balance (1) Charge-offs and Payments Applied (2) Book Value (3) Related Allowance for Loan Losses Coverage % (4) (Dollars in millions) Commercial and industrial $ 187 $ 1 $ 186 $ 33 18.2 % Commercial real estate mortgage—owner-occupied 60 4 56 5 15.0 Commercial real estate construction—owner-occupied 1 — 1 — — Total commercial 248 5 243 38 17.3 Commercial investor real estate mortgage 82 8 74 7 18.3 Commercial investor real estate construction 16 — 16 1 6.3 Total investor real estate 98 8 90 8 16.3 Residential first mortgage 435 10 425 51 14.0 Home equity 292 — 292 5 1.7 Indirect—vehicles 1 — 1 — — Consumer credit card 2 — 2 — — Other consumer 10 — 10 — — Total consumer 740 10 730 56 8.9 $ 1,086 $ 23 $ 1,063 $ 102 11.5 % Total Impaired Loans 2016 Book Value (3) Unpaid Principal Balance (1) Charge-offs and Payments Applied (2) Total Impaired Loans Impaired Loans with No Related Allowance Impaired Loans with Related Allowance Related Allowance for Loan Losses Coverage % (4) (Dollars in millions) Commercial and industrial $ 872 $ 73 $ 799 $ 126 $ 673 $ 171 28.0 % Commercial real estate mortgage—owner-occupied 291 25 266 39 227 58 28.5 Commercial real estate construction—owner-occupied 5 1 4 — 4 2 60.0 Total commercial 1,168 99 1,069 165 904 231 28.3 Commercial investor real estate mortgage 100 9 91 5 86 12 21.0 Commercial investor real estate construction 16 — 16 — 16 1 6.3 Total investor real estate 116 9 107 5 102 13 19.0 Residential first mortgage 476 22 454 — 454 55 16.2 Home equity 304 1 303 — 303 5 2.0 Indirect—vehicles 1 — 1 — 1 — — Consumer credit card 2 — 2 — 2 — — Other consumer 10 — 10 — 10 — — Total consumer 793 23 770 — 770 60 10.5 $ 2,077 $ 131 $ 1,946 $ 170 $ 1,776 $ 304 20.9 % _________ (1) Unpaid principal balance represents the contractual obligation due from the customer and includes the net book value plus charge-offs and payments applied. (2) Charge-offs and payments applied represents cumulative partial charge-offs taken, as well as interest payments received that have been applied against the outstanding principal balance. (3) Book value represents the unpaid principal balance less charge-offs and payments applied; it is shown before any allowance for loan losses. (4) Coverage % represents charge-offs and payments applied plus the related allowance as a percent of the unpaid principal balance. The following table presents the average balances of total impaired loans and interest income for the years ended December 31, 2017 , 2016 and 2015 . Interest income recognized represents interest on accruing loans modified in a TDR. 2017 2016 2015 Average Interest Average Interest Average Interest (In millions) Commercial and industrial $ 747 $ 12 $ 714 $ 6 $ 386 $ 4 Commercial real estate mortgage—owner-occupied 226 5 304 5 345 9 Commercial real estate construction—owner-occupied 5 — 3 — 3 — Total commercial 978 17 1,021 11 734 13 Commercial investor real estate mortgage 81 4 120 8 242 11 Commercial investor real estate construction 39 2 30 1 24 1 Total investor real estate 120 6 150 9 266 12 Residential first mortgage 450 15 469 15 477 15 Home equity 280 14 322 16 354 18 Indirect—vehicles — — 1 — 1 — Consumer credit card 2 — 2 — 2 — Other consumer 9 1 11 1 14 1 Total consumer 741 30 805 32 848 34 Total impaired loans $ 1,839 $ 53 $ 1,976 $ 52 $ 1,848 $ 59
Schedule of loans by class modified in a TDR	2017 Financial Impact of Modifications Considered TDRs Number of Obligors Recorded Investment Increase in Allowance at Modification (Dollars in millions) Commercial and industrial 134 $ 493 $ 10 Commercial real estate mortgage—owner-occupied 118 110 3 Commercial real estate construction—owner-occupied 3 2 — Total commercial 255 605 13 Commercial investor real estate mortgage 42 104 3 Commercial investor real estate construction 5 70 2 Total investor real estate 47 174 5 Residential first mortgage 209 39 5 Home equity 116 9 — Consumer credit card 68 1 — Indirect—vehicles and other consumer 155 2 — Total consumer 548 51 5 850 $ 830 $ 23 2016 Financial Impact of Modifications Considered TDRs Number of Obligors Recorded Investment Increase in Allowance at Modification (Dollars in millions) Commercial and industrial 184 $ 509 $ 12 Commercial real estate mortgage—owner-occupied 117 98 2 Commercial real estate construction—owner-occupied 1 1 — Total commercial 302 608 14 Commercial investor real estate mortgage 80 96 2 Commercial investor real estate construction 9 43 1 Total investor real estate 89 139 3 Residential first mortgage 231 46 6 Home equity 300 15 — Consumer credit card 88 1 — Indirect—vehicles and other consumer 190 2 — Total consumer 809 64 6 1,200 $ 811 $ 23
Loans Modified In Past Twelve Months Which Subsequently Defaulted	The following table presents, by portfolio segment and class, TDRs that defaulted during the years ended December 31, 2017 and 2016 , and that were modified in the previous twelve months (i.e., the twelve months prior to the default). For purposes of this disclosure, default is defined as placement on non-accrual status for the commercial and investor real estate portfolio segments, and 90 days past due and still accruing for the consumer portfolio segment. Consideration of defaults in the calculation of the allowance for loan losses is described in detail in Note 1. 2017 2016 (In millions) Defaulted During the Period, Where Modified in a TDR Twelve Months Prior to Default Commercial and industrial $ 10 $ 28 Commercial real estate mortgage—owner-occupied 1 3 Total commercial 11 31 Commercial investor real estate mortgage — 3 Commercial investor real estate construction — 1 Total investor real estate — 4 Residential first mortgage 9 21 Home equity 1 2 Total consumer 10 23 $ 21 $ 58

(Tables)

(Tables)	12 Months Ended
	Dec. 31, 2017
Transfers and Servicing of Financial Assets [Abstract]
Schedule of Residential Mortgage Servicing Rights Under The Fair Value Measurement Method	The table below presents an analysis of residential MSRs under the fair value measurement method for the years ended December 31 : 2017 2016 2015 (In millions) Carrying value, beginning of year $ 324 $ 252 $ 257 Additions 64 108 36 Increase (decrease) in fair value (1) : Due to change in valuation inputs or assumptions (8 ) 4 (2 ) Economic amortization associated with borrower repayments (44 ) (40 ) (39 ) Carrying value, end of year $ 336 $ 324 $ 252 _________ (1) "Economic amortization associated with borrower repayments" includes both total loan payoffs as well as partial paydowns.
Data And Assumptions Used In The Fair Value Calculation As Well As The Valuation's Sensitivity To Rate Fluctuations Related To Mortgage Servicing Rights	Data and assumptions used in the fair value calculation, as well as the valuation’s sensitivity to rate fluctuations, related to residential MSRs (excluding related derivative instruments) as of December 31 are as follows: 2017 2016 (Dollars in millions) Unpaid principal balance $ 32,076 $ 31,335 Weighted-average CPR (%) 9.9 % 7.6 % Estimated impact on fair value of a 10% increase $ (22 ) $ (19 ) Estimated impact on fair value of a 20% increase $ (39 ) $ (34 ) Option-adjusted spread (basis points) 861 1,054 Estimated impact on fair value of a 10% increase $ (11 ) $ (13 ) Estimated impact on fair value of a 20% increase $ (22 ) $ (27 ) Weighted-average coupon interest rate 4.1 % 4.2 % Weighted-average remaining maturity (months) 281 281 Weighted-average servicing fee (basis points) 27.4 27.5
Schedule Of Fees Resulting From The Servicing Of Residential Mortgage Loans	The following table presents servicing related fees, which includes contractually specified servicing fees, late fees and other ancillary income resulting from the servicing of residential mortgage loans for the years ended December 31 : 2017 2016 2015 (In millions) Servicing related fees and other ancillary income $ 96 $ 86 $ 82

Other Earning Assets (Tables)

Other Earning Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Other Earning Assets [Abstract]
Schedule Of Investments in Federal Reserve Bank Stock And Federal Home Loan Bank Stock	The following table presents the amount of Regions' investments in FRB and FHLB stock as of December 31: 2017 2016 (In millions) Federal Reserve Bank $ 492 $ 494 Federal Home Loan Bank 192 196
Schedule of Property Subject to or Available for Operating Lease	The Company's investments in operating leases represent assets such as equipment, vehicles and aircraft. The following table presents investments in operating leases at December 31: 2017 2016 (In millions) Lease assets $ 685 $ 818 Accumulated depreciation (196 ) (130 ) Investments in operating leases, net $ 489 $ 688
Schedule of Future Minimum Rental Payments Receivable for Operating Leases	The following table presents the minimum future rental payments due from customers for operating leases as of December 31: Future rental payments (In millions) 2018 $ 74 2019 59 2020 44 2021 30 2022 17 Thereafter 20 $ 244

Premises and Equipment (Tables)

Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Premises and Equipment	A summary of premises and equipment at December 31 is as follows: 2017 2016 (In millions) Land $ 484 $ 490 Premises and improvements 1,751 1,730 Furniture and equipment 982 1,025 Software 624 597 Leasehold improvements 388 387 Construction in progress 249 214 4,478 4,443 Accumulated depreciation and amortization (2,414 ) (2,347 ) $ 2,064 $ 2,096

Intangible Assets (Tables)

Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	Goodwill allocated to each reportable segment at December 31 is presented as follows: 2017 2016 (In millions) Corporate Bank $ 2,474 $ 2,474 Consumer Bank 1,978 1,978 Wealth Management 452 452 $ 4,904 $ 4,904
Schedule Of Assumptions Used In Estimating Fair Value	Listed in the tables below are assumptions used in estimating the fair value of each reporting unit for the applicable annual period. The table includes the discount rates used in the income approach, the market multipliers used in the market approaches, and the public company method control premium applied to each reporting unit. These valuation approaches are described further in Note 1. As of Fourth Quarter 2017 Corporate Bank Consumer Bank Wealth Management Discount rate used in income approach 11.25 % 11.00 % 11.25 % Public company method market multiplier (1) 1.8x 2.0x 18.8x Transaction method market multiplier (2) 1.9x 2.6x 24.2x As of Fourth Quarter 2016 Corporate Bank Consumer Bank Wealth Management Discount rate used in income approach 10.00 % 10.25 % 11.50 % Public company method market multiplier (1) 1.5x 1.9x 14.6x Transaction method market multiplier (2) 1.9x 1.9x 23.5x _______ (1) For the Corporate Bank and Consumer Bank reporting units, these multipliers are applied to tangible book value. For the Wealth Management reporting unit, this multiplier is applied to earnings. In addition to the multipliers, a 10 percent control premium was assumed for the Corporate Bank reporting unit, and a 25 percent control premium was assumed for the Consumer Bank and the Wealth Management reporting units based on current market factors. Because the control premium considers potential revenue synergies and cost savings for similar financial services transactions, reporting units operating in businesses that have greater barriers to entry tend to have greater control premiums. (2) For the Corporate Bank and Consumer Bank reporting units, these multipliers are applied to tangible book value. For the Wealth Management reporting unit, this multiplier is applied to earnings.
Summary Of Other Intangible Assets	The following table shows the other intangibles and related accumulated amortization as of December 31: 2017 2016 2017 2016 2017 2016 Gross Carrying Amount Accumulated Amortization Net Carrying Amount (In millions) Core deposit intangibles $ 1,011 $ 1,011 $ 950 $ 932 $ 61 $ 79 Purchased credit card relationship assets 175 175 116 102 59 73 Customer relationship and employment agreement assets 75 75 43 33 32 42 Other—amortizing (1) 19 19 12 10 7 9 FNMA DUS license (2) 15 15 Other—non-amortizing (3) 3 3 $ 1,280 $ 1,280 $ 1,121 $ 1,077 $ 177 $ 221 _________ (1) Includes intangible assets related to acquired trust services, trade names and intellectual property. (2) The DUS license is a non-amortizing intangible asset. (3) Includes non-amortizing intangible assets related to other acquired trust services.
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	The aggregate amount of amortization expense for core deposit intangibles, purchased credit card relationship assets, and other intangible assets is estimated as follows: Year Ended December 31 (In millions) 2018 $ 39 2019 32 2020 26 2021 21 2022 17

Deposits (Tables)

Deposits (Tables)	12 Months Ended
	Dec. 31, 2017
Deposits [Abstract]
Schedule Of Interest-Bearing Deposits	The following schedule presents a detail of interest-bearing deposits at December 31 : 2017 2016 (In millions) Savings $ 8,413 $ 7,840 Interest-bearing transaction 20,161 20,259 Money market—domestic 25,306 27,293 Money market—foreign 23 186 Time deposits 6,859 7,183 Interest-bearing customer deposits 60,762 62,761 Corporate treasury time deposits — 228 $ 60,762 $ 62,989
Schedule Of Aggregate Amount Of Maturities Of All Time Deposits	At December 31, 2017 , the aggregate amounts of maturities of all time deposits (deposits with stated maturities, consisting primarily of certificates of deposit and IRAs) were as follows: December 31, 2017 (In millions) 2018 $ 3,207 2019 940 2020 1,237 2021 893 2022 345 Thereafter 237 $ 6,859

Short-Term Borrowings (Tables)

Short-Term Borrowings (Tables)	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Schedule of Short-term Debt	Following is a summary of short-term borrowings at December 31 : 2017 2016 (In millions) Company funding sources: FHLB advances $ 500 $ — $ 500 $ —

Long-Term Borrowings (Tables)

Long-Term Borrowings (Tables)	12 Months Ended
	Dec. 31, 2017
Long-term Borrowings [Abstract]
Schedule of Long-term Debt Instruments	Long-term borrowings at December 31 consist of the following: 2017 2016 (In millions) Regions Financial Corporation (Parent): 2.00% senior notes due May 2018 $ 101 $ 100 3.20% senior notes due February 2021 1,101 1,102 2.75% senior notes due August 2022 995 — 7.75% subordinated notes due September 2024 100 100 6.75% subordinated debentures due November 2025 158 159 7.375% subordinated notes due December 2037 297 297 Valuation adjustments on hedged long-term debt (50 ) (30 ) 2,702 1,728 Regions Bank: FHLB advances 3,653 4,254 2.25% senior notes due September 2018 749 748 7.50% subordinated notes due May 2018 500 499 6.45% subordinated notes due June 2037 495 495 3.80% affiliate subordinated notes due February 2025 — 150 Other long-term debt 35 40 Valuation adjustments on hedged long-term debt (2 ) (1 ) 5,430 6,185 Elimination of 3.80% affiliate subordinated notes due February 2025 — (150 ) Total consolidated $ 8,132 $ 7,763
Schedule of Maturities of Long-term Debt	The aggregate amount of contractual maturities of all long-term debt in each of the next five years and thereafter is as follows: Year Ended December 31 Regions Financial Corporation (Parent) Regions Bank (In millions) 2018 $ 101 $ 4,899 2019 — 4 2020 — 30 2021 1,066 1 2022 980 — Thereafter 555 496 $ 2,702 $ 5,430

Regulatory Capital Requiremen49

Regulatory Capital Requirements and Regulations (Tables)	12 Months Ended
	Dec. 31, 2017
Banking and Thrift [Abstract]
Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations	The following tables summarize the applicable holding company and bank regulatory capital requirements: December 31, 2017 (1) Minimum Requirement To Be Well Capitalized Amount Ratio Transitional Basis Basel III Regulatory Capital Rules (2) (Dollars in millions) Basel III common equity Tier 1 capital: Regions Financial Corporation $ 11,152 11.05 % 4.50 % N/A Regions Bank 12,560 12.49 4.50 6.50 % Tier 1 capital: Regions Financial Corporation $ 11,964 11.86 % 6.00 % 6.00 % Regions Bank 12,560 12.49 6.00 8.00 Total capital: Regions Financial Corporation $ 13,903 13.78 % 8.00 % 10.00 % Regions Bank 14,042 13.97 8.00 10.00 Leverage capital: Regions Financial Corporation $ 11,964 10.01 % 4.00 % N/A Regions Bank 12,560 10.54 4.00 5.00 % December 31, 2016 Minimum Requirement To Be Well Capitalized Amount Ratio Transitional Basis Basel III Regulatory Capital Rules (2) (Dollars in millions) Basel III common equity Tier 1 capital: Regions Financial Corporation $ 11,481 11.21 % 4.50 % N/A Regions Bank 12,404 12.14 4.50 6.50 % Tier 1 capital: Regions Financial Corporation $ 12,277 11.98 % 6.00 % 6.00 % Regions Bank 12,404 12.14 6.00 8.00 Total capital: Regions Financial Corporation $ 14,501 14.15 % 8.00 % 10.00 % Regions Bank 14,311 14.00 8.00 10.00 Leverage capital: Regions Financial Corporation $ 12,277 10.20 % 4.00 % N/A Regions Bank 12,404 10.34 4.00 5.00 % _________ (1) The 2017 Basel III CET1 capital, Tier 1 capital, Total capital, and Leverage capital ratios are estimated. (2) The 2017 and 2016 capital ratios were calculated at different points of the phase-in period under the Basel III Rules and therefore are not directly comparable.

Stockholders' Equity and Accu50

Stockholders' Equity and Accumulated Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Summary of the non-cumulative perpetual preferred stock	The following table presents a summary of the non-cumulative perpetual preferred stock as of December 31: 2017 2016 Issuance Date Earliest Redemption Date Dividend Rate Liquidation Amount Carrying Amount Carrying Amount (Dollars in millions) Series A 11/1/2012 12/15/2017 6.375 % $ 500 $ 387 $ 387 Series B 4/29/2014 9/15/2024 6.375 % (1) 500 433 433 $ 1,000 $ 820 $ 820 _________ (1) Dividends, if declared, will be paid quarterly at an annual rate equal to (i) for each period beginning prior to September 15, 2024, 6.375% , and (ii) for each period beginning on or after September 15, 2024, three-month LIBOR plus 3.536% .
Schedule of Accumulated Other Comprehensive Income (Loss)	Activity within the balances in accumulated other comprehensive income (loss) is shown in the following tables for the years ended December 31: 2017 Unrealized losses on securities transferred to held to maturity Unrealized gains (losses) on securities available for sale Unrealized gains (losses) on derivative instruments designated as cash flow hedges Defined benefit pension plans and other post employment benefits Accumulated other comprehensive income (loss), net of tax (In millions) Beginning of year $ (33 ) $ (106 ) $ 11 $ (422 ) $ (550 ) Net change 6 (12 ) (51 ) (9 ) (66 ) Reclassification of the Tax Reform related revaluation of deferred tax items within AOCI (6 ) (35 ) (11 ) (81 ) (133 ) End of year $ (33 ) $ (153 ) $ (51 ) $ (512 ) $ (749 ) 2016 Unrealized losses on securities transferred to held to maturity Unrealized gains (losses) on securities available for sale Unrealized gains (losses) on derivative instruments designated as cash flow hedges Defined benefit pension plans and other post employment benefits Accumulated other comprehensive income (loss), net of tax (In millions) Beginning of year $ (47 ) $ (10 ) $ 75 $ (398 ) $ (380 ) Net change 14 (96 ) (64 ) (24 ) (170 ) End of year $ (33 ) $ (106 ) $ 11 $ (422 ) $ (550 ) 2015 Unrealized losses on securities transferred to held to maturity Unrealized gains (losses) on securities available for sale Unrealized gains (losses) on derivative instruments designated as cash flow hedges Defined benefit pension plans and other post employment benefits Accumulated other (In millions) Beginning of year $ (55 ) $ 175 $ 33 $ (391 ) $ (238 ) Net change 8 (185 ) 42 (7 ) (142 ) End of year $ (47 ) $ (10 ) $ 75 $ (398 ) $ (380 )
Reclassification From Accumulated Other Comprehensive Income (Loss)	The following table presents amounts reclassified out of accumulated other comprehensive income (loss) for the years ended December 31: 2017 2016 2015 Details about Accumulated Other Comprehensive Income (Loss) Components Amount Reclassified from Accumulated Other Comprehensive Income (Loss) (1) Amount Reclassified from Accumulated Other Comprehensive Income (Loss) (1) Amount Reclassified from Accumulated Other Comprehensive Income (Loss) (1) Affected Line Item in the Consolidated Statements of Income (In millions) Unrealized losses on securities transferred to held to maturity: $ (10 ) $ (22 ) $ (14 ) Net interest income and other financing income 4 8 6 Tax (expense) or benefit $ (6 ) $ (14 ) $ (8 ) Net of tax Unrealized gains and (losses) on available for sale securities: $ 19 $ 6 $ 29 Securities gains, net (7 ) (2 ) (10 ) Tax (expense) or benefit $ 12 $ 4 $ 19 Net of tax Gains (losses) on cash flow hedges: Interest rate contracts $ 86 $ 143 $ 153 Net interest income and other financing income (33 ) (54 ) (58 ) Tax (expense) or benefit $ 53 $ 89 $ 95 Net of tax Amortization of defined benefit pension plans and other post employment benefits: Prior service cost $ — $ — $ (1 ) (2) Actuarial gains (losses) and settlements (48 ) (34 ) (47 ) (2) (48 ) (34 ) (48 ) Total before tax 17 12 17 Tax (expense) or benefit $ (31 ) $ (22 ) $ (31 ) Net of tax Total reclassifications for the period $ 28 $ 57 $ 75 Net of tax _________ (1) Amounts in parentheses indicate reductions to net income. (2) These accumulated other comprehensive income (loss) components are included in the computation of net periodic pension cost and are included in salaries and employee benefits on the consolidated statements of income (see Note 18 for additional details).

Earnings (Loss) per Common Sh51

Earnings (Loss) per Common Share (Tables)	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The following table sets forth the computation of basic earnings (loss) per common share and diluted earnings (loss) per common share for the years ended December 31 : 2017 2016 2015 (In millions, except per share data) Numerator: Income from continuing operations $ 1,257 $ 1,158 $ 1,075 Preferred stock dividends (64 ) (64 ) (64 ) Income from continuing operations available to common shareholders 1,193 1,094 1,011 Income (loss) from discontinued operations, net of tax 6 5 (13 ) Net income available to common shareholders $ 1,199 $ 1,099 $ 998 Denominator: Weighted-average common shares outstanding—basic 1,186 1,255 1,325 Potential common shares 12 6 9 Weighted-average common shares outstanding—diluted 1,198 1,261 1,334 Earnings per common share from continuing operations available to common shareholders (1) : Basic $ 1.01 $ 0.87 $ 0.76 Diluted 1.00 0.87 0.76 Earnings (loss) per common share from discontinued operations (1) : Basic $ 0.01 $ 0.00 $ (0.01 ) Diluted 0.00 0.00 (0.01 ) Earnings per common share (1) : Basic $ 1.01 $ 0.87 $ 0.75 Diluted 1.00 0.87 0.75 ________ (1) Certain per share amounts may not appear to reconcile due to rounding.

Share-Based Payments (Tables)

Share-Based Payments (Tables)	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary Of Compensation Costs Recognized In The Consolidated Statements Of Operations	The following table summarizes the elements of compensation cost recognized in the consolidated statements of income for the years ended December 31 : 2017 2016 2015 (In millions) Compensation cost of share-based compensation awards: Restricted and performance stock awards $ 62 $ 52 $ 50 Tax benefits related to share-based compensation cost (1) (23 ) (20 ) (19 ) Compensation cost of share-based compensation awards, net of tax $ 39 $ 32 $ 31 ________ (1) The tax benefits rela ted to share-based compensation cost for 2017 exclude (a) excess tax benefits of $10 million related to settled share-based compensation awards and (b) tax expense of $5 million related to expired stock options.
Summary Of Activity Related To Stock Options	The following table summarizes the activity for 2017 , 2016 and 2015 related to stock options: Number of Options Weighted- Average Exercise Price Aggregate Intrinsic Value (In millions) Weighted-Average Remaining Contractual Term Outstanding at December 31, 2014 25,316,676 $ 23.07 $ 28 2.83 yrs. Granted — — Exercised (546,455 ) 6.93 Forfeited or expired (5,420,064 ) 31.88 Outstanding at December 31, 2015 19,350,157 $ 21.06 $ 20 2.45 yrs. Granted — — Exercised (1,954,064 ) 5.80 Forfeited or expired (3,941,046 ) 34.39 Outstanding at December 31, 2016 13,455,047 $ 19.37 $ 34 1.83 yrs. Granted — — Exercised (1,204,138 ) 6.69 Forfeited or expired (2,843,011 ) 34.00 Outstanding at December 31, 2017 9,407,898 $ 16.58 $ 35 1.05 yrs. Exercisable at December 31, 2017 9,407,898 $ 16.58 $ 35 1.05 yrs.
Summary Of Activity Related to Restricted Stock Awards And Performance Stock Awards	ds. Activity related to restricted stock awards and performance stock awards for 2017 , 2016 and 2015 is summarized as follows: Number of Shares/Units Weighted-Average Grant Date Fair Value Non-vested at December 31, 2014 18,427,409 $ 8.07 Granted 6,670,905 9.22 Vested (8,222,576 ) 6.09 Forfeited (501,496 ) 8.81 Non-vested at December 31, 2015 16,374,242 $ 9.51 Granted 6,867,672 7.93 Vested (5,829,974 ) 8.28 Forfeited (852,998 ) 9.07 Non-vested at December 31, 2016 16,558,942 $ 9.31 Granted 3,993,591 14.57 Vested (4,657,544 ) 11.06 Forfeited (631,955 ) 10.04 Non-vested at December 31, 2017 15,263,034 $ 10.12

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2017
Defined Benefit Plan [Abstract]
Schedule of Defined Benefit Plans Disclosures	The following table sets forth the plans’ change in benefit obligation, plan assets and funded status, using a December 31 measurement date, and amounts recognized in the consolidated balance sheets at December 31 : Qualified Plans Non-qualified Plans Total 2017 2016 2017 2016 2017 2016 (In millions) Change in benefit obligation Projected benefit obligation, beginning of year $ 1,979 $ 1,895 $ 180 $ 167 $ 2,159 $ 2,062 Service cost 34 35 4 4 38 39 Interest cost 72 73 5 5 77 78 Actuarial (gains) losses 202 67 12 13 214 80 Benefit payments (150 ) (88 ) (7 ) (10 ) (157 ) (98 ) Administrative expenses (3 ) (3 ) — — (3 ) (3 ) Plan settlements — — (43 ) — (43 ) — Plan amendments — — — 1 — 1 Projected benefit obligation, end of year $ 2,134 $ 1,979 $ 151 $ 180 $ 2,285 $ 2,159 Change in plan assets Fair value of plan assets, beginning of year $ 1,990 $ 1,930 $ — $ — $ 1,990 $ 1,930 Actual return on plan assets 306 151 — — 306 151 Company contributions 75 — 50 10 125 10 Benefit payments (150 ) (88 ) (7 ) (10 ) (157 ) (98 ) Administrative expenses (3 ) (3 ) — — (3 ) (3 ) Plan settlements — — (43 ) — (43 ) — Fair value of plan assets, end of year $ 2,218 $ 1,990 $ — $ — $ 2,218 $ 1,990 Funded status and accrued benefit cost at measurement date $ 84 $ 11 $ (151 ) $ (180 ) $ (67 ) $ (169 ) Amount recognized in the Consolidated Balance Sheets: Other assets (liabilities) $ 84 $ 11 $ (151 ) $ (180 ) $ (67 ) $ (169 ) Pre-tax amounts recognized in Accumulated Other Comprehensive (Income) Loss: Net actuarial loss (gain) $ 644 $ 637 $ 48 $ 52 $ 692 $ 689 Prior service cost (credit) — — 1 1 1 1 $ 644 $ 637 $ 49 $ 53 $ 693 $ 690
Components Of Net Periodic Benefit Costs	Net periodic pension cost, which is recorded in salaries and employee benefits on the consolidated statements of income, included the following components for the years ended December 31 : Qualified Plans Non-qualified Plans Total 2017 2016 2015 2017 2016 2015 2017 2016 2015 (In millions) Service cost $ 34 $ 35 $ 40 $ 4 $ 4 $ 4 $ 38 $ 39 $ 44 Interest cost 72 73 84 5 5 6 77 78 90 Expected return on plan assets (143 ) (145 ) (152 ) — — — (143 ) (145 ) (152 ) Amortization of actuarial loss 32 31 43 4 3 4 36 34 47 Amortization of prior service cost — — — — — 1 — — 1 Settlement charge — — — 12 — 2 12 — 2 Net periodic pension (benefit) cost $ (5 ) $ (6 ) $ 15 $ 25 $ 12 $ 17 $ 20 $ 6 $ 32
Estimated Amounts That Will Be Amortized From Accumulated Other Comprehensive Income (Loss) Into Net Periodic Benefit Cost	The estimated amounts that will be amortized from accumulated other comprehensive income (loss) into net periodic benefit cost in 2018 are as follows: Qualified Plans Non-qualified Plans (In millions) Actuarial loss $ 33 $ 4 $ 33 $ 4
Schedule of Assumptions Used	The assumptions used to determine benefit obligations at December 31 are as follows: Qualified Plans Non-qualified Plans 2017 2016 2017 2016 Discount rate 3.71 % 4.32 % 3.50 % 3.93 % Rate of annual compensation increase 3.75 % 3.75 % 3.75 % 3.75 % The weighted-average assumptions used to determine net periodic benefit cost for the years ended December 31 are as follows: Qualified Plans Non-qualified Plans 2017 2016 2015 2017 2016 2015 Discount rate 4.34 % 4.56 % 4.20 % 3.93 % 4.19 % 3.75 % Expected long-term rate of return on plan assets 7.25 % 7.75 % 7.75 % N/A N/A N/A Rate of annual compensation increase 3.75 % 3.75 % 3.75 % 3.75 % 3.75 % 3.75 %
Presentation Of The Fair Value Of Regions' Qualified Defined-Benefit Pension Plans'	The following table presents the fair value of Regions’ qualified pension plans’ financial assets as of December 31 : 2017 2016 Level 1 Level 2 Level 3 Fair Value Level 1 Level 2 Level 3 Fair Value (In millions) Cash and cash equivalents $ 48 $ — $ — $ 48 $ 52 $ — $ — $ 52 Fixed income securities: U.S. Treasury and federal agency securities $ — $ 172 $ — $ 172 $ — $ 144 $ — $ 144 Corporate bonds — 216 — 216 — 170 — 170 Total fixed income securities $ — $ 388 $ — $ 388 $ — $ 314 $ — $ 314 Equity securities: Domestic $ 427 $ — $ — $ 427 $ 303 $ — $ — $ 303 International 32 — — 32 21 — — 21 Total equity securities $ 459 $ — $ — $ 459 $ 324 $ — $ — $ 324 International mutual funds $ 100 $ — $ — $ 100 $ 192 192 $ — $ — $ 192 Total assets in the fair value hierarchy $ 607 $ 388 $ — $ 995 $ 568 $ 314 $ — $ 882 Collective trust funds: Fixed income fund (1) $ 388 $ 320 Common stock fund (1) 265 244 International fund (1) 216 182 Total collective trust funds $ 869 $ 746 Hedge funds measured at NAV (1) $ 46 $ 16 Real estate funds measured at NAV (1) $ 197 $ 239 Private equity funds measured at NAV (1) $ 111 $ 107 $ 2,218 $ 1,990 __________ (1) In accordance with accounting guidance adopted by Regions in 2016, investments that are measured at fair value using the net asset value per share (or its equivalent) practical expedient are no longer required to be classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of amounts reported in the fair value hierarchy to amounts reported on the balance sheet. See Note 1 for further discussion.
Information About The Expected Cash Flows For The Qualified Pension Plan	Information about the expected cash flows for the qualified and non-qualified plans is as follows: Qualified Non-qualified (In millions) Expected Employer Contributions: 2018 $ — $ 10 Expected Benefit Payments: 2018 $ 93 $ 10 2019 95 11 2020 98 11 2021 102 22 2022 105 16 Next five years 573 56

Other Non-Interest Income and54

Other Non-Interest Income and Expense (Tables)	12 Months Ended
	Dec. 31, 2017
Other Income and Expenses [Abstract]
Schedule Of Other Non-Interest Income and Expense	The following is a detail of other non-interest income from continuing operations for the years ended December 31 : 2017 2016 2015 (In millions) Capital markets fee income and other $ 161 $ 152 $ 104 Insurance commissions and fees 145 148 140 Bank-owned life insurance 81 95 74 Commercial credit fee income 71 73 76 Investment services fee income 60 58 55 Insurance proceeds — 50 91 Market value adjustments on employee benefit assets 16 3 (3 ) Other miscellaneous income 70 116 115 $ 604 $ 695 $ 652 The following is a detail of other non-interest expense from continuing operations for the years ended December 31 : 2017 2016 2015 (In millions) Outside services $ 172 $ 154 $ 149 FDIC insurance assessments 108 99 105 Professional, legal and regulatory expenses 95 89 137 Marketing 93 101 98 Credit/checkcard expenses 50 55 54 Branch consolidation, property and equipment charges 22 58 56 Visa class B shares expense 19 15 9 Provision (credit) for unfunded credit losses (16 ) 17 (13 ) Loss on early extinguishment of debt — 14 43 Other miscellaneous expenses 452 437 422 $ 995 $ 1,039 $ 1,060

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Taxes [Abstract]
Schedule of Components of Income Tax Expense (Benefit)	The components of income tax expense from continuing operations for the years ended December 31 were as follows: 2017 2016 2015 (In millions) Current income tax expense: Federal $ 376 $ 444 $ 293 State 30 21 7 Total current expense $ 406 $ 465 $ 300 Deferred income tax expense: Federal $ 172 $ 2 $ 115 State 36 47 40 Total deferred expense $ 208 $ 49 $ 155 Total income tax expense $ 614 $ 514 $ 455 __________ Note: The table above does not include total income tax expense (benefit) from discontinued operations of $2 million , $3 million , and $(9) million in 2017 , 2016 and 2015 , respectively. The deferred income tax expense reflected in discontinued operations was $1 million , $18 million and $46 million in 2017 , 2016 and 2015 , respectively.
Reconciliation Of Continuing Operations Effective Income Tax Rate Table	Income taxes from continuing operations for financial reporting purposes differs from the amount computed by applying the statutory federal income tax rate of 35 percent for the years ended December 31 , as shown in the following table: 2017 2016 2015 (Dollars in millions) Tax on income from continuing operations computed at statutory federal income tax rate $ 655 $ 585 $ 535 Increase (decrease) in taxes resulting from: State income tax, net of federal tax effect 43 44 30 Tax-exempt interest (54 ) (49 ) (44 ) Affordable housing investment amortization, net of tax benefits (excluding Tax Reform) (52 ) (50 ) (47 ) Impact of Tax Reform 52 — — Bank-owned life insurance (32 ) (37 ) (30 ) Lease financing 16 28 18 Other, net (14 ) (7 ) (7 ) Income tax expense $ 614 $ 514 $ 455 Effective tax rate 32.8 % 30.7 % 29.7 % ___ _______ Note: Income tax expense includes amortization of affordable housing investments of $160 million (including $23 million due to impact of Tax Reform), $117 million and $103 million for 2017, 2016 and 2015, respectively. Income tax expense for 2015 includes a benefit of $15 million related to an improved methodology implemented to estimate the effective state tax rate.
Summary Of Significant Components Of Deferred Tax Assets And Liabilities	Significant components of the Company’s net deferred tax asset at December 31 are listed below: 2017 2016 (In millions) Deferred tax assets: Unrealized gains and losses included in stockholders’ equity $ 253 $ 338 Allowance for loan losses 249 447 State net operating loss carryfowards, net of federal tax effect 82 88 Accrued expenses 55 92 Federal tax credit carryforwards 13 13 Fixed assets 4 — Employee benefits and deferred compensation — 37 Other 33 59 Total deferred tax assets 689 1,074 Less: valuation allowance (34 ) (30 ) Total deferred tax assets less valuation allowance 655 1,044 Deferred tax liabilities: Lease financing 292 424 Goodwill and intangibles 99 156 Mortgage servicing rights 63 93 Fixed assets — 15 Other 38 48 Total deferred tax liabilities 492 736 Net deferred tax asset $ 163 $ 308
Summary Of Details Of Tax Carryforwards Table	The following table provides details of the Company’s tax carryforwards at December 31, 2017 , including the expiration dates, any related valuation allowance and the amount of taxable earnings necessary to fully realize each net deferred tax asset balance: Expiration Dates Deferred Tax Asset Balance Valuation Allowance Net Deferred Tax Asset Balance Pre-Tax Earnings Necessary to Realize (1) (In millions) Alternate minimum tax credits-federal None (2) $ 13 $ — $ 13 $ N/A Net operating losses-states 2018-2022 42 (9 ) 33 553 Net operating losses-states 2023-2029 33 (21 ) 12 240 Net operating losses-states 2030-2037 7 (4 ) 3 44 Other credits-states 2018-2022 — — — N/A Other credits-states 2023-2029 1 — 1 N/A ________ (1) N/A indicates that credits are not measured on a pre-tax basis. (2) Tax Reform repealed the AMT for tax years beginning after December 31, 2017 and provides a mechanism to utilize any AMT credit carryover through 2020 with any remaining credits being fully refundable in 2021.
Schedule of Unrecognized Tax Benefits Roll Forward	A reconciliation of the beginning and ending amount of unrecognized tax benefits (“UTBs”) is as follows: 2017 2016 2015 (In millions) Balance at beginning of year $ 31 $ 38 $ 50 Additions based on tax positions related to the current year — 3 2 Reductions based on tax positions taken in a prior period — (6 ) (8 ) Settlements — (3 ) (6 ) Expiration of statute of limitations (4 ) (1 ) — Balance at end of year $ 27 $ 31 $ 38

Derivative Financial Instrume56

Derivative Financial Instruments and Hedging Activities (Tables)	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule Of Derivative Instruments Notional And Fair Values	The following tables present the notional amount and estimated fair value of derivative instruments on a gross basis as of December 31, 2017 and 2016 . The variation margin payments made during 2017 for derivatives cleared through the Chicago Mercantile Exchange are legally characterized as settlements of the derivatives. As a result, these positions are reflected as settled with no fair value presented for purposes of the balance sheet and related disclosures. 2017 2016 Notional Amount Estimated Fair Value Notional Amount Estimated Fair Value Gain (1) Loss (1) Gain (1) Loss (1) (In millions) Derivatives in fair value hedging relationships: Interest rate swaps $ 3,060 $ 1 $ 43 $ 2,257 $ 7 $ 40 Derivatives in cash flow hedging relationships: Interest rate swaps 6,825 5 188 9,000 19 269 Total derivatives designated as hedging instruments $ 9,885 $ 6 $ 231 $ 11,257 $ 26 $ 309 Derivatives not designated as hedging instruments: Interest rate swaps $ 40,841 $ 308 $ 342 $ 41,851 $ 412 $ 467 Interest rate options 4,598 23 15 3,877 24 12 Interest rate futures and forward commitments 20,404 6 5 18,605 11 6 Other contracts 5,721 51 48 5,813 106 93 Total derivatives not designated as hedging instruments $ 71,564 $ 388 $ 410 $ 70,146 $ 553 $ 578 Total derivatives $ 81,449 $ 394 $ 641 $ 81,403 $ 579 $ 887 _________ (1) Derivatives in a gain position are recorded as other assets and derivatives in a loss position are recorded as other liabilities on the consolidated balance sheets.
Schedule Of Effect Of Hedging Derivative Instruments On Statements Of Operations	The following tables present the effect of hedging derivative instruments on the consolidated statements of income for the years ended December 31 : Gain or (Loss) Recognized in Income on Derivatives Location of Amounts Recognized in Income on Derivatives and Related Hedged Item Gain or (Loss) Recognized in Income on Related Hedged Item 2017 2016 2015 2017 2016 2015 (In millions) (In millions) Fair Value Hedges: Interest rate swaps on: Debt/CDs $ 2 $ 12 $ 17 Interest expense $ (1 ) $ (3 ) $ 4 Debt/CDs (20 ) (33 ) (1 ) Other non-interest expense 22 32 1 Securities available for sale (4 ) (9 ) (14 ) Interest income — — — Securities available for sale 1 — (8 ) Other non-interest expense (2 ) (2 ) 6 Total $ (21 ) $ (30 ) $ (6 ) $ 19 $ 27 $ 11 Effective Portion (3) Gain or (Loss) Recognized in AOCI (1) Location of Amounts Reclassified from AOCI into Income Gain or (Loss) Reclassified from AOCI into Income (2) 2017 2016 2015 2017 2016 2015 (In millions) (In millions) Cash Flow Hedges: Interest rate swaps $ (51 ) $ (64 ) $ 42 Interest income on loans $ 86 $ 143 $ 153 Total $ (51 ) $ (64 ) $ 42 $ 86 $ 143 $ 153 ____ (1) After-tax (2) Pre-tax (3) All cash flow hedges were highly effective for all periods presented, and the change in fair value attributed to hedge ineffectiveness was not material.
Schedule Of Gains (Losses) Recognized In Income Related To Derivatives Not Designated As Hedging Instruments	The following table presents the location and amount of gain or (loss) recognized in income on derivatives not designated as hedging instruments in the consolidated statements of income for the years ended December 31 : Derivatives Not Designated as Hedging Instruments 2017 2016 2015 (In millions) Capital markets fee income and other (1) : Interest rate swaps $ 11 $ 13 $ 14 Interest rate options 28 23 14 Interest rate futures and forward commitments 10 4 3 Other contracts (10 ) (3 ) 11 Total capital markets fee income and other 39 37 42 Mortgage income: Interest rate swaps 2 (2 ) 13 Interest rate options (7 ) (2 ) (1 ) Interest rate futures and forward commitments (3 ) 8 3 Total mortgage income (8 ) 4 15 $ 31 $ 41 $ 57 ______ (1) Capital markets fee income and other is included in Other income on the consolidated statements of income.
Schedule Of Gross Derivative Positions, Including Collateral Posted or Received	The following table presents the Company's gross derivative positions, including collateral posted or received, as of December 31, 2017 and 2016 . Offsetting Derivative Assets Offsetting Derivative Liabilities 2017 2016 2017 2016 (In millions) Gross amounts subject to offsetting $ 231 $ 414 $ 342 $ 583 Gross amounts not subject to offsetting 163 165 299 304 Gross amounts recognized 394 579 641 887 Gross amounts offset in the consolidated balance sheets (1) 141 241 238 541 Net amounts presented in the consolidated balance sheets 253 338 403 346 Gross amounts not offset in the consolidated balance sheets: Financial instruments 2 4 50 50 Cash collateral received/posted — — 257 227 Net amounts $ 251 $ 334 $ 96 $ 69 _________ (1) At December 31, 2017 , gross amounts of derivative assets and liabilities offset in the consolidated balance sheets presented above include cash collateral received of $34 million and cash collateral posted of $131 million . At December 31, 2016 , the gross amounts of derivative assets and liabilities offset in the consolidated balance sheets presented above include cash collateral received of $48 million and cash collateral posted of

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Schedule Of Assets And Liabilities At Fair Value Measured On A Recurring Basis And Non-Recurring Basis	The following table presents assets and liabilities measured at estimated fair value on a recurring basis and non-recurring basis as of December 31: 2017 2016 Level 1 Level 2 Level 3 (1) Total Estimated Fair Value Level 1 Level 2 Level 3 (1) Total Estimated Fair Value (In millions) Recurring fair value measurements Trading account securities $ 189 $ — $ — $ 189 $ 124 $ — $ — $ 124 Securities available for sale: U.S. Treasury securities $ 331 $ — $ — $ 331 $ 303 $ — $ — $ 303 Federal agency securities — 28 — 28 — 35 — 35 Obligations of states and political subdivisions — — — — — 1 — 1 Mortgage-backed securities: Residential agency — 17,431 — 17,431 — 17,371 — 17,371 Residential non-agency — — 3 3 — — 4 4 Commercial agency — 3,714 — 3,714 — 3,463 — 3,463 Commercial non-agency — 788 — 788 — 1,129 — 1,129 Corporate and other debt securities — 1,105 3 1,108 — 1,271 3 1,274 Equity securities 225 — — 225 201 — — 201 Total securities available for sale $ 556 $ 23,066 $ 6 $ 23,628 $ 504 $ 23,270 $ 7 $ 23,781 Mortgage loans held for sale $ — $ 325 $ — $ 325 $ — $ 414 $ 33 $ 447 Residential mortgage servicing rights $ — $ — $ 336 $ 336 $ — $ — $ 324 $ 324 Derivative assets: Interest rate swaps $ — $ 314 $ — $ 314 $ — $ 438 $ — $ 438 Interest rate options — 18 5 23 — 13 11 24 Interest rate futures and forward commitments — 6 — 6 — 11 — 11 Other contracts 2 49 — 51 2 104 — 106 Total derivative assets $ 2 $ 387 $ 5 $ 394 $ 2 $ 566 $ 11 $ 579 Derivative liabilities: Interest rate swaps $ — $ 573 $ — $ 573 $ — $ 776 $ — $ 776 Interest rate options — 15 — 15 — 12 — 12 Interest rate futures and forward commitments — 5 — 5 — 6 — 6 Other contracts 2 46 — 48 1 92 — 93 Total derivative liabilities $ 2 $ 639 $ — $ 641 $ 1 $ 886 $ — $ 887 Non-recurring fair value measurements Loans held for sale $ — $ — $ 20 $ 20 $ — $ — $ 7 $ 7 Foreclosed property and other real estate — 24 9 33 — 29 6 35 _________ (1) All following disclosures related to Level 3 recurring and non-recurring assets do not include those deemed to be immaterial.
Rollforward For Assets And Liabilities Measured At Fair Value On A Recurring Basis With Level 3 Significant Unobservable Inputs	The following tables illustrate rollforwards for all material assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the years ended December 31, 2017 , 2016 and 2015 , respectively. Year Ended December 31, 2017 Total Realized / Unrealized Gains or Losses Opening Balance January 1, 2017 Included in Earnings Included in Other Compre- hensive Income (Loss) Purchases Sales Issuances Settlements Transfers into Level 3 Transfers out of Level 3 Closing Balance December 31, 2017 (In millions) Level 3 Instruments Only Residential mortgage servicing rights $ 324 (52 ) (1) — 64 — — — — — $ 336 Year Ended December 31, 2016 Opening Balance January 1, 2016 Total Realized / Unrealized Gains or Losses Purchases Sales Issuances Settlements Transfers into Level 3 Transfers out of Level 3 Closing Included in Earnings Included in Other Compre- hensive Income (Loss) (In millions) Level 3 Instruments Only Residential mortgage servicing rights $ 252 (36 ) (1) — 108 — — — — — $ 324 Year Ended December 31, 2015 Opening Balance January 1, 2015 Total Realized / Unrealized Gains or Losses Purchases Sales Issuances Settlements Transfers into Level 3 Transfers out of Level 3 Closing Balance December 31, 2015 Included in Earnings Included in Other Compre- hensive Income (Loss) (In millions) Level 3 Instruments Only Residential mortgage servicing rights $ 257 (41 ) (1) — 36 — — — — — $ 252 _________ (1) Included in mortgage income.
Schedule Of Fair Value Adjustments Related To Non-Recurring Fair Value Measurements	The following table presents the fair value adjustments related to non-recurring fair value measurements for the years ended December 31: 2017 2016 (In millions) Loans held for sale $ (22 ) $ (26 ) Foreclosed property and other real estate (31 ) (42 )
Summary Of Quantitative Information About Level 3 Measurements	The following tables present detailed information regarding material assets and liabilities measured at fair value using significant unobservable inputs (Level 3) as of December 31, 2017 , 2016 and 2015 . The tables include the valuation techniques and the significant unobservable inputs utilized. The range of each significant unobservable input as well as the weighted-average within the range utilized at December 31, 2017 , 2016 and 2015 are included. Following the tables are a description of the valuation techniques and the sensitivity of the techniques to changes in the significant unobservable inputs. December 31, 2017 Level 3 Estimated Fair Value at December 31, 2017 Valuation Technique Unobservable Input(s) Quantitative Range of Unobservable Inputs and (Weighted-Average) (Dollars in millions) Recurring fair value measurements: Residential mortgage servicing rights (1) $336 Discounted cash flow Weighted-average CPR (%) 7.9% - 28.1% (9.9%) OAS (%) 8.1% - 15.0% (8.6%) December 31, 2016 Level 3 Valuation Technique Unobservable Input(s) Quantitative Range of Unobservable Inputs and (Weighted-Average) (Dollars in millions) Recurring fair value measurements: Residential mortgage servicing rights (1) $324 Discounted cash flow Weighted-average CPR (%) 5.7% - 24.3% (7.6%) OAS (%) 8.2% - 13.6% (10.5%) December 31, 2015 Level 3 Valuation Unobservable Quantitative Range of (Dollars in millions) Recurring fair value measurements: Residential mortgage servicing rights (1) $252 Discounted cash flow Weighted-average CPR (%) 10.5% - 11.5% (10.9%) OAS (%) 8.7% - 13.3% (10.0%) _________ (1) See Note 7 for additional disclosures related to assumptions used in the fair value calculation for residential MSRs.
Fair Value Option, Fair Value and Unpaid Principal Balance	The following table summarizes the difference between the aggregate fair value and the aggregate unpaid principal balance for mortgage loans held for sale measured at fair value at December 31 : 2017 2016 Aggregate Fair Value Aggregate Unpaid Principal Aggregate Fair Value Less Aggregate Unpaid Principal Aggregate Fair Value Aggregate Unpaid Principal Aggregate Fair Value Less Aggregate Unpaid Principal (In millions) Mortgage loans held for sale, at fair value $ 325 $ 314 $ 11 $ 447 $ 443 $ 4 Interest income on mortgage loans held for sale is recognized based on contractual rates and is reflected in interest income on loans held for sale in the consolidated statements of income. The following table details net gains and losses resulting from changes in fair value of these loans, which were recorded in mortgage and capital markets income in the consolidated statements of income for the years presented. These changes in fair value are mostly offset by economic hedging activities. An immaterial portion of these amounts was attributable to changes in instrument-specific credit risk. 2017 2016 (In millions) Net gains (losses) resulting from changes in fair value $ 5 $ (8 )
Schedule Of Carrying Amounts And Estimated Fair Values Of Financial Instruments	The carrying amounts and estimated fair values, as well as the level within the fair value hierarchy, of the Company’s financial instruments as of December 31, 2017 are as follows: 2017 Carrying Amount Estimated Fair Value (1) Level 1 Level 2 Level 3 (In millions) Financial assets: Cash and cash equivalents $ 3,981 $ 3,981 $ 3,981 $ — $ — Trading account securities 189 189 189 — — Securities held to maturity 1,658 1,667 — 1,667 — Securities available for sale 23,628 23,628 556 23,066 6 Loans held for sale 348 348 — 328 20 Loans (excluding leases), net of unearned income and allowance for loan losses (2)(3) 77,942 76,871 — — 76,871 Other earning assets (4) 988 988 — 988 — Derivative assets 394 394 2 387 5 Financial liabilities: Derivative liabilities 641 641 2 639 — Deposits 96,889 96,927 — 96,927 — Short-term borrowings 500 500 — 500 — Long-term borrowings 8,132 8,517 — 7,757 760 Loan commitments and letters of credit 79 540 — — 540 _________ (1) Estimated fair values are consistent with an exit price concept. The assumptions used to estimate the fair values are intended to approximate those that a market participant would use in a hypothetical orderly transaction. In estimating fair value, the Company maintains a corporate governance program to make adjustments for estimated changes in interest rates, market liquidity and credit spreads in the periods they are deemed to have occurred. Historically, the Company has utilized the results of a third-party vendor model to support its primary valuation approach for loans. For the year ended 2017, the Company implemented an internally-supported loan valuation model as its primary valuation approach for loans, including unfunded loan commitments and letters of credit. (2) The estimated fair value of portfolio loans assumes sale of the loans to a third-party financial investor. Accordingly, the value to the Company if the loans were held to maturity is not reflected in the fair value estimate. In the current whole loan market, financial investors are generally requiring a higher rate of return than the return inherent in loans if held to maturity. The fair value discount on the loan portfolio's net carrying amount at December 31, 2017 was $1.1 billion or 1.4 percent. (3) Excluded from this table is the capital lease carrying amount of $1.1 billion at December 31, 2017 . (4) Excluded from this table is the operating lease carrying amount of $489 million at December 31, 2017 . The carrying amounts and estimated fair values, as well as the level within the fair value hierarchy, of the Company's financial instruments as of December 31, 2016 are as follows: 2016 Carrying Amount Estimated Fair Value (1) Level 1 Level 2 Level 3 (In millions) Financial assets: Cash and cash equivalents $ 5,451 $ 5,451 $ 5,451 $ — $ — Trading account securities 124 124 124 — — Securities held to maturity 1,362 1,369 — 1,369 — Securities available for sale 23,781 23,781 504 23,270 7 Loans held for sale 718 722 — 689 33 Loans (excluding leases), net of unearned income and allowance for loan losses (2)(3) 78,128 74,063 — — 74,063 Other earning assets (4) 956 956 — 956 — Derivative assets 579 579 2 566 11 Financial liabilities: Derivative liabilities 887 887 1 886 — Deposits 99,035 99,081 — 99,081 — Short-term borrowings — — — — — Long-term borrowings 7,763 8,008 — 5,408 2,600 Loan commitments and letters of credit 102 484 — — 484 _________ (1) Estimated fair values are consistent with an exit price concept. The assumptions used to estimate the fair values are intended to approximate those that a market participant would use in a hypothetical orderly transaction. In estimating fair value, the Company maintains a corporate governance program to make adjustments for estimated changes in interest rates, market liquidity and credit spreads in the periods they are deemed to have occurred. Historically, the Company has utilized the results of a third-party vendor model to support its primary valuation approach for loans. (2) The estimated fair value of portfolio loans assumes sale of the loans to a third-party financial investor. Accordingly, the value to the Company if the loans were held to maturity is not reflected in the fair value estimate. In the current whole loan market, financial investors are generally requiring a higher rate of return than the return inherent in loans if held to maturity. The fair value discount on the loan portfolio's net carrying amount at December 31, 2016 was $4.1 billion or 5.2 percent. (3) Excluded from this table is the capital lease carrying amount of $876 million at December 31, 2016 . (4) Excluded from this table is the operating lease carrying amount of $688 million at December 31, 2016 .

Business Segment Information (T

Business Segment Information (Tables)	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Schedule Of Financial Information By Reportable Segment	The following tables present financial information for each reportable segment for the year ended December 31 : 2017 Corporate Bank Consumer Bank Wealth Management Other Continuing Operations Discontinued Operations Consolidated (In millions) Net interest income and other financing income (loss) $ 1,422 $ 2,140 $ 192 $ (214 ) $ 3,540 $ — $ 3,540 Provision (credit) for loan losses 258 297 20 (425 ) 150 — 150 Non-interest income 467 1,116 450 72 2,105 — 2,105 Non-interest expense 865 2,051 481 227 3,624 (8 ) 3,616 Income (loss) before income taxes 766 908 141 56 1,871 8 1,879 Income tax expense (benefit) 291 345 53 (75 ) 614 2 616 Net income (loss) $ 475 $ 563 $ 88 $ 131 $ 1,257 $ 6 $ 1,263 Average assets $ 51,680 $ 34,997 $ 3,117 $ 34,182 $ 123,976 $ — $ 123,976 2016 Corporate Bank Consumer Bank Wealth Management Other Continuing Operations Discontinued Operations Consolidated (In millions) Net interest income and other financing income (loss) $ 1,449 $ 2,047 $ 175 $ (273 ) $ 3,398 $ — $ 3,398 Provision (credit) for loan losses 286 290 22 (336 ) 262 — 262 Non-interest income 485 1,126 427 115 2,153 — 2,153 Non-interest expense 876 2,061 469 211 3,617 (8 ) 3,609 Income (loss) before income taxes 772 822 111 (33 ) 1,672 8 1,680 Income tax expense (benefit) 293 312 42 (133 ) 514 3 517 Net income (loss) $ 479 $ 510 $ 69 $ 100 $ 1,158 $ 5 $ 1,163 Average assets $ 54,006 $ 34,597 $ 3,232 $ 33,671 $ 125,506 $ — $ 125,506 2015 Corporate Bank Consumer Bank Wealth Management Other Continuing Operations Discontinued Operations Consolidated (In millions) Net interest income and other financing income (loss) $ 1,512 $ 2,018 $ 167 $ (390 ) $ 3,307 $ — $ 3,307 Provision (credit) for loan losses 301 276 22 (358 ) 241 — 241 Non-interest income 435 1,074 408 154 2,071 — 2,071 Non-interest expense 887 2,067 458 195 3,607 22 3,629 Income (loss) before income taxes 759 749 95 (73 ) 1,530 (22 ) 1,508 Income tax expense (benefit) 288 285 37 (155 ) 455 (9 ) 446 Net income (loss) $ 471 $ 464 $ 58 $ 82 $ 1,075 $ (13 ) $ 1,062 Average assets $ 53,308 $ 33,415 $ 3,185 $ 32,357 $ 122,265 $ — $ 122,265

Commitments, Contingencies an59

Commitments, Contingencies and Guarantees (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Credit Risk Of Off- Balance Sheet Financial Instruments By Contractual Amounts	Credit risk associated with these instruments as of December 31 is represented by the contractual amounts indicated in the following table: 2017 2016 (In millions) Unused commitments to extend credit $ 45,705 $ 44,408 Standby letters of credit 1,348 1,425 Commercial letters of credit 76 46 Liabilities associated with standby letters of credit 26 34 Assets associated with standby letters of credit 28 34 Reserve for unfunded credit commitments 53 69
Operating Leases of Lessee Disclosure	The approximate future minimum rental commitments as of December 31, 2017 , for all non-cancelable leases with initial or remaining terms of one year or more are shown in the following table. Included in these amounts are all renewal options reasonably assured of being exercised. Premises Equipment Total (In millions) 2018 $ 104 $ 31 $ 135 2019 101 13 114 2020 90 5 95 2021 76 — 76 2022 65 — 65 Thereafter 252 — 252 $ 688 $ 49 $ 737

Parent Company Only Financial60

Parent Company Only Financial Statements (Tables) - Parent Company [Member]	12 Months Ended
	Dec. 31, 2017
Schedule of Condensed Balance Sheet	Balance Sheets December 31 2017 2016 (In millions) Assets Interest-bearing deposits in other banks $ 1,693 $ 1,043 Loans to subsidiaries 20 20 Securities available for sale 18 20 Premises and equipment, net 46 42 Investments in subsidiaries: Banks 16,548 16,693 Non-banks 446 409 16,994 17,102 Other assets 303 453 Total assets $ 19,074 $ 18,680 Liabilities and Stockholders’ Equity Long-term borrowings $ 2,702 $ 1,728 Other liabilities 180 288 Total liabilities 2,882 2,016 Stockholders’ equity: Preferred stock 820 820 Common stock 12 13 Additional paid-in capital 15,858 17,092 Retained earnings 1,628 666 Treasury stock, at cost (1,377 ) (1,377 ) Accumulated other comprehensive income (loss), net (749 ) (550 ) Total stockholders’ equity 16,192 16,664 Total liabilities and stockholders’ equity $ 19,074 $ 18,680
Schedule of Condensed Income Statement	Statements of Income Year Ended December 31 2017 2016 2015 (In millions) Income: Dividends received from subsidiaries $ 1,300 $ 1,190 $ 860 Interest from subsidiaries 6 7 7 Insurance proceeds — — 91 Other 2 4 — 1,308 1,201 958 Expenses: Salaries and employee benefits 65 56 51 Interest 80 73 60 Furniture and equipment expense 4 3 1 Professional, legal and regulatory expenses — 2 3 Other 68 89 81 217 223 196 Income before income taxes and equity in undistributed earnings of subsidiaries 1,091 978 762 Income tax benefit (65 ) (66 ) (45 ) Income from continuing operations 1,156 1,044 807 Discontinued operations: Income (loss) from discontinued operations before income taxes 8 8 (22 ) Income tax expense (benefit) 2 3 (9 ) Income (loss) from discontinued operations, net of tax 6 5 (13 ) Income before equity in undistributed earnings of subsidiaries and preferred dividends 1,162 1,049 794 Equity in undistributed earnings of subsidiaries: Banks 73 102 257 Non-banks 28 12 11 101 114 268 Net income 1,263 1,163 1,062 Preferred stock dividends (64 ) (64 ) (64 ) Net income available to common shareholders $ 1,199 $ 1,099 $ 998
Schedule of Condensed Cash Flow Statement	Statements of Cash Flows Year Ended December 31 2017 2016 2015 (In millions) Operating activities: Net income $ 1,263 $ 1,163 $ 1,062 Adjustments to reconcile net cash from operating activities: Equity in undistributed earnings of subsidiaries (101 ) (114 ) (268 ) Depreciation, amortization and accretion, net 2 2 1 Loss on sale of assets 1 — — Loss on early extinguishment of debt — 14 — Net change in operating assets and liabilities: Other assets (19 ) 33 16 Other liabilities 2 (38 ) (213 ) Other 41 68 48 Net cash from operating activities 1,189 1,128 646 Investing activities: (Investment in) / repayment of investment in subsidiaries 141 (60 ) (239 ) Principal payments received on loans to subsidiaries — — 10 Principal advances on loans to subsidiaries — (10 ) (10 ) Proceeds from sales and maturities of securities available for sale 9 8 6 Purchases of securities available for sale (6 ) (8 ) (7 ) Net (purchases of) / proceeds from sales of assets 6 (1 ) (43 ) Other, net 2 — — — Net cash from investing activities 152 (71 ) (283 ) Financing activities: Proceeds from long-term borrowings 999 1,107 — Payments on long-term borrowings — (658 ) (500 ) Cash dividends on common stock (346 ) (317 ) (304 ) Cash dividends on preferred stock (64 ) (64 ) (64 ) Repurchase of common stock (1,275 ) (839 ) (623 ) Other (5 ) (2 ) 12 Net cash from financing activities (691 ) (773 ) (1,479 ) Net change in cash and cash equivalents 650 284 (1,116 ) Cash and cash equivalents at beginning of year 1,043 759 1,875 Cash and cash equivalents at end of year $ 1,693 $ 1,043 $ 759

Summary of Significant Accoun61

Summary of Significant Accounting Policies (Supplemental Cash Flows) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounting Policies [Abstract]
Interest Paid, Net	$ 363	$ 299	$ 268
Income Taxes Paid, Net	181	314	129
Operating Leases transferred to Other Earning Assets from Loans	0	0	879
Real Estate Owned, Transfer to Real Estate Owned	80	100	156
Transfer of Portfolio Loans and Leases to Held-for-sale	41	247	69
Transfer of Loans Held-for-sale to Portfolio Loans	8	5	3
Properties Transferred To Held For Sale	33	53	38
Loans settled with trading account securities	33	0	0
Operating lease assets settled with trading account securities	$ 15	$ 0	$ 0

Summary of Significant Accoun62

Summary of Significant Accounting Policies (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Modifications [Line Items]
New Revenue Recognition Standard, Amount of 2016 Non-Interest Income Within Scope When Adopted	$ 1,600,000,000
Commercial And Investor Real Estate Loans Subject To Charge Offs Maximum	$ 250,000
Days For Commercial and Investor Real Estate Loans To Be Evaluated As Potential Charge Off	180 days
Days For Consumer First Lien Postion Loans To Be Evaluated As Potential Charge Off	180 days
Days For Home Equity Loans In Second Lien Position To Be Evaluated As Potential Charge Off	120 days
Days For Consumer Close-Ended Loans To Be Evaluated As Potential Charge Off	120 days
Days for Consumer Loans in an Open-Ended Position to be Evaluated for Potential Charge Off	180 days
Days for Credit Cards to be Evaluated for Potential Charge Off	180 days
Quantitative Scope For Specific Evaluation For Impairment	$ 2,500,000
Service cost	38,000,000	$ 39,000,000	$ 44,000,000
Minimum [Member]
Financing Receivable, Modifications [Line Items]
Service cost	35,000,000
Operating Lease, Right-of-Use Asset	400,000,000
Maximum [Member]
Financing Receivable, Modifications [Line Items]
Service cost	40,000,000
Operating Lease, Right-of-Use Asset	$ 700,000,000
Leasehold improvements | Minimum [Member]
Financing Receivable, Modifications [Line Items]
Property, Plant and Equipment, Useful Life	7 years
Leasehold improvements | Maximum [Member]
Financing Receivable, Modifications [Line Items]
Property, Plant and Equipment, Useful Life	40 years
Furniture and equipment | Minimum [Member]
Financing Receivable, Modifications [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Furniture and equipment | Maximum [Member]
Financing Receivable, Modifications [Line Items]
Property, Plant and Equipment, Useful Life	10 years

Variable Interest Entities (Sch

Variable Interest Entities (Schedule of Equity Method Investments) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Schedule of Equity Method Investments [Line Items]
Amortization Method Qualified Affordable Housing Project Investments	$ 1,144	$ 1,013
Equity Method Investments	20	21
Unfunded Commitments	348	301
Short Term Construction Loans And Letters Of Credit Commitments	317	249
Funded Portion Of Short Term Construction Loans And Letters Of Credit	$ 129	$ 103

Variable Interest Entities (Nar

Variable Interest Entities (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Equity Method Investments [Line Items]
Amortization Method Qualified Affordable Housing Project Investments, Amortization	$ 160	$ 117
Amortization Method Qualified Affordable Housing Project Investments	1,144	1,013
Tax credits recognized for low income housing tax credits	102	54	$ 0
Other tax benefits recognized for low income housing tax credits			$ 15
Amortization Expense Due to Tax Reform [Member]
Schedule of Equity Method Investments [Line Items]
Amortization Method Qualified Affordable Housing Project Investments, Amortization	23
Low Income Housing Tax Credit Investments [Member]
Schedule of Equity Method Investments [Line Items]
Tax credits recognized for low income housing tax credits	144	130
Other tax benefits recognized for low income housing tax credits	45	$ 37
Syndications [Member]
Schedule of Equity Method Investments [Line Items]
Amortization Method Qualified Affordable Housing Project Investments	$ 2

Discontinued Operations (Detail

Discontinued Operations (Details) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Non-interest expense:
Professional and legal expenses		$ 95	$ 89	$ 137
Other		995	1,039	1,060
Total non-interest expense		3,624	3,617	3,607
Income (loss) from discontinued operations before income taxes		8	8	(22)
Income tax expense (benefit)		2	3	(9)
Income (loss) from discontinued operations, net of tax		$ 6	$ 5	$ (13)
Earnings (loss) per common share from discontinued operations:
Basic	[1]	$ 0.01	$ 0	$ (0.01)
Diluted	[1]	$ 0	$ 0	$ (0.01)
Discontinued Operations [Member]
Non-interest expense:
Professional and legal expenses		$ (10)	$ (9)	$ 21
Other		2	1	1
Total non-interest expense		(8)	(8)	22
Income (loss) from discontinued operations before income taxes		8	8	(22)
Income tax expense (benefit)		2	3	(9)
Income (loss) from discontinued operations, net of tax		$ 6	$ 5	$ (13)
Earnings (loss) per common share from discontinued operations:
Basic		$ 0.01	$ 0	$ (0.01)
Diluted		$ 0	$ 0	$ (0.01)
[1]	Certain per share amounts may not appear to reconcile due to rounding.

Securities (Schedule Of Amortiz

Securities (Schedule Of Amortized Cost, Gross Unrealized Gains And Losses, And Estimated Fair Value Of Securities Available For Sale And Securities Held To Maturity) (Details) - USD ($) $ in Millions		Dec. 31, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis		$ 23,830	$ 23,950
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax		82	139
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax		(284)	(308)
Available-for-sale securities, net carrying value		23,628	23,781
Securities available for sale		23,628	23,781
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, amortized cost		1,702	1,416
Held To Maturity Securities Gross Unrealized Gains	[1]	0	0
Held To Maturity Securities Gross Unrealized Losses	[1]	(44)	(54)
Securities held to maturity		1,658	1,362
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain		17	12
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss		(8)	(5)
Securities held to maturity, estimated fair value		1,667	1,369
US Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis		333	303
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax		0	1
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax		(2)	(1)
Available-for-sale securities, net carrying value		331	303
Securities available for sale		331	303
Federal agency securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis		28	35
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax		0	0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax		0	0
Available-for-sale securities, net carrying value		28	35
Securities available for sale		28	35
Obligations of States and Political Subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis			1
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax			0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax			0
Available-for-sale securities, net carrying value			1
Securities available for sale			1
Residential Agency [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis		17,622	17,531
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax		53	95
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax		(244)	(255)
Available-for-sale securities, net carrying value		17,431	17,371
Securities available for sale		17,431	17,371
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, amortized cost		1,051
Securities held to maturity, estimated fair value		1,019
Residential Non-Agency [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis		3	4
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax		0	0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax		0	0
Available-for-sale securities, net carrying value		3	4
Securities available for sale		3	4
Commercial Agency [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis		3,739	3,486
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax		5	9
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax		(30)	(32)
Available-for-sale securities, net carrying value		3,714	3,463
Securities available for sale		3,714	3,463
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, amortized cost		651
Securities held to maturity, estimated fair value		648
Commercial Non Agency [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis		787	1,124
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax		4	8
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax		(3)	(3)
Available-for-sale securities, net carrying value		788	1,129
Securities available for sale		788	1,129
Corporate and other debt securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis		1,093	1,272
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax		20	19
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax		(5)	(17)
Available-for-sale securities, net carrying value		1,108	1,274
Securities available for sale		1,108	1,274
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis		225	194
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax		0	7
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax		0	0
Available-for-sale securities, net carrying value		225	201
Securities available for sale		225	201
Residential Agency [Member]
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, amortized cost		1,051	1,249
Held To Maturity Securities Gross Unrealized Gains	[1]	0	0
Held To Maturity Securities Gross Unrealized Losses	[1]	(40)	(49)
Securities held to maturity		1,011	1,200
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain		12	12
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss		(4)	(3)
Securities held to maturity, estimated fair value		1,019	1,209
Commercial Agency [Member]
Schedule of Held-to-maturity Securities [Line Items]
Securities held to maturity, amortized cost		651	167
Held To Maturity Securities Gross Unrealized Gains	[1]	0	0
Held To Maturity Securities Gross Unrealized Losses	[1]	(4)	(5)
Securities held to maturity		647	162
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain		5	0
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss		(4)	(2)
Securities held to maturity, estimated fair value		$ 648	$ 160
[1]	The gross unrealized losses recognized in OCI on held to maturity securities resulted from a transfer of available for sale securities to held to maturity in the second quarter of 2013.

Securities (Schedule Of Cost An

Securities (Schedule Of Cost And Estimated Fair Value Of Securities Available For Sale And Securities Held To Maturity By Contractual Maturity) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Securities held to maturity, amortized cost	$ 1,702	$ 1,416
Securities held to maturity, estimated fair value	1,667	1,369
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Amortized Cost Basis	33
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value	33
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Amortized Cost Basis	876
Available-for-sale Securities, Debt Maturities, Year Two Through Five, Fair Value	878
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Amortized Cost Basis	462
Available-for-sale Securities, Debt Maturities, Year Six Through Ten, Fair Value	471
Available-for-sale Securities, Debt Maturities, after Ten Years, Amortized Cost Basis	83
Available-for-sale Securities, Debt Maturities, after Ten Years, Fair Value	85
Available-for-sale Securities, Amortized Cost Basis	23,830	23,950
Securities available for sale	23,628	23,781
Residential Agency [Member]
Securities held to maturity, amortized cost	1,051
Securities held to maturity, estimated fair value	1,019
Available-for-sale Securities, Amortized Cost Basis	17,622	17,531
Securities available for sale	17,431	17,371
Residential Non-Agency [Member]
Available-for-sale Securities, Amortized Cost Basis	3	4
Securities available for sale	3	4
Commercial Agency [Member]
Securities held to maturity, amortized cost	651
Securities held to maturity, estimated fair value	648
Available-for-sale Securities, Amortized Cost Basis	3,739	3,486
Securities available for sale	3,714	3,463
Commercial Non Agency [Member]
Available-for-sale Securities, Amortized Cost Basis	787	1,124
Securities available for sale	788	1,129
Equity Securities [Member]
Available-for-sale Securities, Amortized Cost Basis	225	194
Securities available for sale	$ 225	$ 201

Securities (Schedule Of Gross U

Securities (Schedule Of Gross Unrealized Losses And Estimated Fair Value Of Securities Available For Sale) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Unrealized Loss And Fair Value On Securities [Line Items]
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Estimated Fair Value	$ 0	$ 850
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	(26)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Estimated Fair Value	1,169	519
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(39)	(21)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Estimated Fair Value	1,169	1,369
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	(39)	(47)
Available For Sale Securities, Continuous Unrealized Loss Position, Less Than Twelve Months, Estimated Fair Value	7,767	15,166
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(55)	(285)
Available For Sale Securities, Continuous Unrealized Loss Position, Twelve Months or More, Estimated Fair Value	9,349	1,027
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(229)	(23)
Available For Sale Securities, Continuous Unrealized Loss, Estimated Fair Value	17,116	16,193
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(284)	(308)
US Treasury Securities [Member]
Unrealized Loss And Fair Value On Securities [Line Items]
Available For Sale Securities, Continuous Unrealized Loss Position, Less Than Twelve Months, Estimated Fair Value	221	112
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(1)	(1)
Available For Sale Securities, Continuous Unrealized Loss Position, Twelve Months or More, Estimated Fair Value	84	18
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1)	0
Available For Sale Securities, Continuous Unrealized Loss, Estimated Fair Value	305	130
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(2)	(1)
Residential Agency [Member]
Unrealized Loss And Fair Value On Securities [Line Items]
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Estimated Fair Value	0	850
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	(26)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Estimated Fair Value	1,019	359
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(32)	(14)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Estimated Fair Value	1,019	1,209
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	(32)	(40)
Available For Sale Securities, Continuous Unrealized Loss Position, Less Than Twelve Months, Estimated Fair Value	5,157	12,071
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(40)	(245)
Available For Sale Securities, Continuous Unrealized Loss Position, Twelve Months or More, Estimated Fair Value	8,195	570
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(204)	(10)
Available For Sale Securities, Continuous Unrealized Loss, Estimated Fair Value	13,352	12,641
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(244)	(255)
Commercial Agency [Member]
Unrealized Loss And Fair Value On Securities [Line Items]
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Estimated Fair Value	0	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Estimated Fair Value	150	160
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(7)	(7)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Estimated Fair Value	150	160
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	(7)	(7)
Available For Sale Securities, Continuous Unrealized Loss Position, Less Than Twelve Months, Estimated Fair Value	1,666	2,199
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(10)	(31)
Available For Sale Securities, Continuous Unrealized Loss Position, Twelve Months or More, Estimated Fair Value	904	45
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(20)	(1)
Available For Sale Securities, Continuous Unrealized Loss, Estimated Fair Value	2,570	2,244
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(30)	(32)
Commercial Non Agency [Member]
Unrealized Loss And Fair Value On Securities [Line Items]
Available For Sale Securities, Continuous Unrealized Loss Position, Less Than Twelve Months, Estimated Fair Value	393	402
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(2)	(2)
Available For Sale Securities, Continuous Unrealized Loss Position, Twelve Months or More, Estimated Fair Value	61	176
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(1)	(1)
Available For Sale Securities, Continuous Unrealized Loss, Estimated Fair Value	454	578
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	(3)	(3)
All Other Securities [Member]
Unrealized Loss And Fair Value On Securities [Line Items]
Available For Sale Securities, Continuous Unrealized Loss Position, Less Than Twelve Months, Estimated Fair Value	330	382
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(2)	(6)
Available For Sale Securities, Continuous Unrealized Loss Position, Twelve Months or More, Estimated Fair Value	105	218
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(3)	(11)
Available For Sale Securities, Continuous Unrealized Loss, Estimated Fair Value	435	600
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ (5)	$ (17)

Securities (Schedule Of Gross G

Securities (Schedule Of Gross Gains And Gross Losses On Available For Sale Securities) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Gross realized gains		$ 25	$ 36	$ 44
Gross realized losses		(5)	(28)	(8)
Other than Temporary Impairment		(1)	(2)	(7)
Gain (Loss) on Sale of Securities, Net (Excluding Trading Securities)	[1]	$ 19	$ 6	$ 29
[1]	The securities gains (losses), net balances above exclude net trading securities gains of $3 million recognized during 2017.

Securities (Narrative) (Details

Securities (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)security	Dec. 31, 2016USD ($)security
Schedule of Available-for-sale Securities [Line Items]
Trading Securities, Realized Gain (Loss)	$ 3
Securities pledged as collateral	$ 8,100	$ 11,600
Number of individual positions in unrealized loss position | security	1,762	1,613
US Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities pledged as collateral	$ 50	$ 50

Loans (Schedule Of Loan Portfol

Loans (Schedule Of Loan Portfolio, Net Of Unearned Income) (Details) - USD ($) $ in Millions	Dec. 31, 2017		Dec. 31, 2016		Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	$ 79,947	[1]	$ 80,095	[1]	$ 81,162
Loans and Leases Receivable, Deferred Income	43		141
Commercial And Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	36,115		35,012
Commercial Real Estate Mortgage - Owner-Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	6,193		6,867
Commercial Real Estate Construction - Owner-Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	332		334
Total Commercial Investor Real Estate Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	4,062		4,087
Total Commercial Investor Real Estate Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	1,772		2,387
Residential First Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	14,061		13,440
Home Equity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	10,164		10,687
Indirect-vehicles [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	3,326		4,040
Indirect-other consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	1,467		920
Consumer Credit Card Financing Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	1,290		1,196
Other Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	1,165		1,125
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	42,640		42,213		43,782
Total Investor Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	5,834		6,474		6,947
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	$ 31,473		$ 31,408		$ 30,433
[1]	Loans are presented net of unearned income, unamortized discounts and premiums and net deferred loan costs of $43 million and $141 million at December 31, 2017 and 2016, respectively.

Loans (Regions' Investment In L

Loans (Regions' Investment In Leveraged Leases Included Within Commercial And Industrial Loans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Receivables [Abstract]
Leveraged Leases, Net Investment in Leveraged Leases Disclosure, Rental Receivables, Net	$ 248	$ 303
Leveraged Leases, Net Investment in Leveraged Leases Disclosure, Residual Value of Leased Assets	196	203
Leveraged Leases, Net Investment in Leveraged Leases Disclosure, Deferred Income	160	184
Pre-tax income from leveraged leases	22	28	$ 34
Income tax expense on income from leveraged leases	$ 24	$ 31	$ 33

Loans (Narrative) (Details)

Loans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Leveraged lease termination gains	$ 1	$ 8	$ 8
Leveraged lease termination gains related income tax expense	1	11	$ 1
Loans Pledged for Federal Home Loan Bank Debt	22,000
Federal Reserve Bank [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Pledged for Federal Reserve Bank Debt	21,900
Indirect-vehicles [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Indirect loans purchased	$ 238
Indirect-vehicles and Indirect-other consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Indirect loans purchased		$ 985

Allowance For Credit Losses (Na

Allowance For Credit Losses (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Loans And Leases [Line Items]
Total Loans, New TDRs	$ 501	$ 542
Consumer Loans Default at 90 Days Past Due and Still Accruing	90 days
Re-defaulted commercial and investor real estate loans modified in a TDR during the period and on non-accrual status	$ 4
Restructured binding unfunded commitments	$ 20
Minimum [Member]
Loans And Leases [Line Items]
Financing period for consumer loans, in years	15 years
Maximum [Member]
Loans And Leases [Line Items]
Financing period for consumer loans, in years	30 years

Allowance For Credit Losses (An

Allowance For Credit Losses (Analysis Of The Allowance For Credit Losses By Portfolio Segment) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017		Dec. 31, 2016		Dec. 31, 2015
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period	$ 1,091		$ 1,106		$ 1,103
Provision for loan losses	150		262		241
Loan Losses:
Charge-offs	(434)		(398)		(403)
Recoveries	127		121		165
Net loan losses	(307)		(277)		(238)
Allowance for loan losses, end of period	934		1,091		1,106
Reserve For Unfunded Credit Commitments [Roll Forward]
Reserve for unfunded credit commitments, beginning of year	69		52		65
Provision (credit) for unfunded credit losses	(16)		17		(13)
Reserve for unfunded credit commitments, end of year	53		69		52
Financing Receivable, Allowance for Credit Losses	987		1,160		1,158
Portion of ending allowance for loan losses:
Individually evaluated for impairment	226		304		283
Collectively evaluated for impairment	708		787		823
Portion of loan portfolio ending balance:
Individually evaluated for impairment	1,558		1,946		1,769
Collectively evaluated for impairment	78,389		78,149		79,393
Loans, net of unearned income	79,947	[1]	80,095	[1]	81,162
Commercial Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period	753		758		654
Provision for loan losses	(28)		95		191
Loan Losses:
Charge-offs	(176)		(143)		(154)
Recoveries	42		43		67
Net loan losses	(134)		(100)		(87)
Allowance for loan losses, end of period	591		753		758
Reserve For Unfunded Credit Commitments [Roll Forward]
Reserve for unfunded credit commitments, beginning of year	64		47		57
Provision (credit) for unfunded credit losses	(15)		17		(10)
Reserve for unfunded credit commitments, end of year	49		64		47
Financing Receivable, Allowance for Credit Losses	640		817		805
Portion of ending allowance for loan losses:
Individually evaluated for impairment	171		231		189
Collectively evaluated for impairment	420		522		569
Portion of loan portfolio ending balance:
Individually evaluated for impairment	756		1,069		743
Collectively evaluated for impairment	41,884		41,144		43,039
Loans, net of unearned income	42,640		42,213		43,782
Total Investor Real Estate [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period	85		97		150
Provision for loan losses	(42)		(23)		(65)
Loan Losses:
Charge-offs	(2)		(2)		(15)
Recoveries	23		13		27
Net loan losses	21		11		12
Allowance for loan losses, end of period	64		85		97
Reserve For Unfunded Credit Commitments [Roll Forward]
Reserve for unfunded credit commitments, beginning of year	5		5		8
Provision (credit) for unfunded credit losses	(1)		0		(3)
Reserve for unfunded credit commitments, end of year	4		5		5
Financing Receivable, Allowance for Credit Losses	68		90		102
Portion of ending allowance for loan losses:
Individually evaluated for impairment	8		13		26
Collectively evaluated for impairment	56		72		71
Portion of loan portfolio ending balance:
Individually evaluated for impairment	96		107		191
Collectively evaluated for impairment	5,738		6,367		6,756
Loans, net of unearned income	5,834		6,474		6,947
Consumer Portfolio Segment [Member]
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for loan losses, beginning of period	253		251		299
Provision for loan losses	220		190		115
Loan Losses:
Charge-offs	(256)		(253)		(234)
Recoveries	62		65		71
Net loan losses	(194)		(188)		(163)
Allowance for loan losses, end of period	279		253		251
Reserve For Unfunded Credit Commitments [Roll Forward]
Reserve for unfunded credit commitments, beginning of year	0		0		0
Provision (credit) for unfunded credit losses	0		0		0
Reserve for unfunded credit commitments, end of year	0		0		0
Financing Receivable, Allowance for Credit Losses	279		253		251
Portion of ending allowance for loan losses:
Individually evaluated for impairment	47		60		68
Collectively evaluated for impairment	232		193		183
Portion of loan portfolio ending balance:
Individually evaluated for impairment	706		770		835
Collectively evaluated for impairment	30,767		30,638		29,598
Loans, net of unearned income	$ 31,473		$ 31,408		$ 30,433
[1]	Loans are presented net of unearned income, unamortized discounts and premiums and net deferred loan costs of $43 million and $141 million at December 31, 2017 and 2016, respectively.

Allowance For Credit Losses (Cr

Allowance For Credit Losses (Credit Quality Indicators) (Details) - USD ($) $ in Millions	Dec. 31, 2017		Dec. 31, 2016		Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	$ 79,947	[1]	$ 80,095	[1]	$ 81,162
Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	36,115		35,012
Commercial Real Estate Mortgage - Owner-Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	6,193		6,867
Commercial Real Estate Construction - Owner-Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	332		334
Total Commercial Investor Real Estate Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	4,062		4,087
Total Commercial Investor Real Estate Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	1,772		2,387
Residential First Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	14,061		13,440
Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	10,164		10,687
Indirect-vehicles [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	3,326		4,040
Indirect-other consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	1,467		920
Consumer Credit Card Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	1,290		1,196
Other Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	1,165		1,125
Pass [Member] | Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	34,420		32,619
Pass [Member] | Commercial Real Estate Mortgage - Owner-Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	5,674		6,190
Pass [Member] | Commercial Real Estate Construction - Owner-Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	313		308
Pass [Member] | Total Commercial Investor Real Estate Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	3,905		3,766
Pass [Member] | Total Commercial Investor Real Estate Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	1,706		2,192
Special Mention [Member] | Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	686		658
Special Mention [Member] | Commercial Real Estate Mortgage - Owner-Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	236		221
Special Mention [Member] | Commercial Real Estate Construction - Owner-Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	3		8
Special Mention [Member] | Total Commercial Investor Real Estate Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	63		190
Special Mention [Member] | Total Commercial Investor Real Estate Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	19		129
Substandard [Member] | Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	605		1,112
Substandard [Member] | Commercial Real Estate Mortgage - Owner-Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	165		246
Substandard [Member] | Commercial Real Estate Construction - Owner-Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	10		15
Substandard [Member] | Total Commercial Investor Real Estate Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	89		114
Substandard [Member] | Total Commercial Investor Real Estate Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	46		66
Accrual [Member] | Residential First Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	14,014		13,390
Accrual [Member] | Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	10,095		10,595
Accrual [Member] | Indirect-vehicles [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	3,326		4,040
Accrual [Member] | Indirect-other consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	1,467		920
Accrual [Member] | Consumer Credit Card Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	1,290		1,196
Accrual [Member] | Other Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	1,165		1,125
Non-Accrual [Member] | Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	404		623
Non-Accrual [Member] | Commercial Real Estate Mortgage - Owner-Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	118		210
Non-Accrual [Member] | Commercial Real Estate Construction - Owner-Occupied [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	6		3
Non-Accrual [Member] | Total Commercial Investor Real Estate Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	5		17
Non-Accrual [Member] | Total Commercial Investor Real Estate Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	1		0
Non-Accrual [Member] | Residential First Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	47		50
Non-Accrual [Member] | Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	69		92
Non-Accrual [Member] | Indirect-vehicles [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	0		0
Non-Accrual [Member] | Indirect-other consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	0		0
Non-Accrual [Member] | Consumer Credit Card Financing Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	0		0
Non-Accrual [Member] | Other Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	0		0
Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	31,473		31,408		30,433
Consumer Portfolio Segment [Member] | Accrual [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	31,357		31,266
Consumer Portfolio Segment [Member] | Non-Accrual [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	116		142
Total Investor Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	5,834		6,474		6,947
Total Investor Real Estate [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	5,611		5,958
Total Investor Real Estate [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	82		319
Total Investor Real Estate [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	135		180
Total Investor Real Estate [Member] | Non-Accrual [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	6		17
Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	42,640		42,213		$ 43,782
Commercial Portfolio Segment [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	40,407		39,117
Commercial Portfolio Segment [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	925		887
Commercial Portfolio Segment [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	780		1,373
Commercial Portfolio Segment [Member] | Non-Accrual [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans, net of unearned income	$ 528		$ 836
[1]	Loans are presented net of unearned income, unamortized discounts and premiums and net deferred loan costs of $43 million and $141 million at December 31, 2017 and 2016, respectively.

Allowance For Credit Losses (Sc

Allowance For Credit Losses (Schedule Of Aging Analysis Of Days Past Due (DPD) For Each Portfolio Class) (Details) - USD ($) $ in Millions	Dec. 31, 2017		Dec. 31, 2016		Dec. 31, 2015
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	$ 724		$ 760
90 plus DPD, Accrual Loans	291		283
Total Accrual	79,297		79,100
Financing Receivable, Recorded Investment, Nonaccrual Status	650		995
Loans, net of unearned income	79,947	[1]	80,095	[1]	$ 81,162
Commercial And Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	39		76
90 plus DPD, Accrual Loans	4		6
Total Accrual	35,711		34,389
Financing Receivable, Recorded Investment, Nonaccrual Status	404		623
Loans, net of unearned income	36,115		35,012
Commercial Real Estate Mortgage - Owner-Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	27		38
90 plus DPD, Accrual Loans	1		2
Total Accrual	6,075		6,657
Financing Receivable, Recorded Investment, Nonaccrual Status	118		210
Loans, net of unearned income	6,193		6,867
Commercial Real Estate Construction - Owner-Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	0		1
90 plus DPD, Accrual Loans	0		0
Total Accrual	326		331
Financing Receivable, Recorded Investment, Nonaccrual Status	6		3
Loans, net of unearned income	332		334
Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	66		115
90 plus DPD, Accrual Loans	5		8
Total Accrual	42,112		41,377
Financing Receivable, Recorded Investment, Nonaccrual Status	528		836
Loans, net of unearned income	42,640		42,213
Total Commercial Investor Real Estate Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	3		14
90 plus DPD, Accrual Loans	1		0
Total Accrual	4,057		4,070
Financing Receivable, Recorded Investment, Nonaccrual Status	5		17
Loans, net of unearned income	4,062		4,087
Commercial Investor Real Estate Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	0		0
90 plus DPD, Accrual Loans	0		0
Total Accrual	1,771		2,387
Financing Receivable, Recorded Investment, Nonaccrual Status	1		0
Loans, net of unearned income	1,772		2,387
Total Investor Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	3		14
90 plus DPD, Accrual Loans	1		0
Total Accrual	5,828		6,457
Financing Receivable, Recorded Investment, Nonaccrual Status	6		17
Loans, net of unearned income	5,834		6,474
Residential First Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	396		374
90 plus DPD, Accrual Loans	216		212
Total Accrual	14,014		13,390
Financing Receivable, Recorded Investment, Nonaccrual Status	47		50
Loans, net of unearned income	14,061		13,440
Home Equity [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	117		115
90 plus DPD, Accrual Loans	37		33
Total Accrual	10,095		10,595
Financing Receivable, Recorded Investment, Nonaccrual Status	69		92
Loans, net of unearned income	10,164		10,687
Indirect-vehicles [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	70		80
90 plus DPD, Accrual Loans	9		10
Total Accrual	3,326		4,040
Financing Receivable, Recorded Investment, Nonaccrual Status	0		0
Loans, net of unearned income	3,326		4,040
Indirect-other consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	14		8
90 plus DPD, Accrual Loans	0		0
Total Accrual	1,467		920
Financing Receivable, Recorded Investment, Nonaccrual Status	0		0
Loans, net of unearned income	1,467		920
Consumer Credit Card Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	37		31
90 plus DPD, Accrual Loans	19		15
Total Accrual	1,290		1,196
Financing Receivable, Recorded Investment, Nonaccrual Status	0		0
Loans, net of unearned income	1,290		1,196
Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	21		23
90 plus DPD, Accrual Loans	4		5
Total Accrual	1,165		1,125
Financing Receivable, Recorded Investment, Nonaccrual Status	0		0
Loans, net of unearned income	1,165		1,125
Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	655		631
90 plus DPD, Accrual Loans	285		275
Total Accrual	31,357		31,266
Financing Receivable, Recorded Investment, Nonaccrual Status	116		142
Loans, net of unearned income	31,473		31,408
Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	276		337
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial And Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	28		59
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Real Estate Mortgage - Owner-Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	18		29
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Real Estate Construction - Owner-Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	0		1
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	46		89
Financing Receivables, 30 to 59 Days Past Due [Member] | Total Commercial Investor Real Estate Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	1		6
Financing Receivables, 30 to 59 Days Past Due [Member] | Commercial Investor Real Estate Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	0		0
Financing Receivables, 30 to 59 Days Past Due [Member] | Total Investor Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	1		6
Financing Receivables, 30 to 59 Days Past Due [Member] | Residential First Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	95		99
Financing Receivables, 30 to 59 Days Past Due [Member] | Home Equity [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	53		60
Financing Receivables, 30 to 59 Days Past Due [Member] | Indirect-vehicles [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	48		56
Financing Receivables, 30 to 59 Days Past Due [Member] | Indirect-other consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	9		5
Financing Receivables, 30 to 59 Days Past Due [Member] | Consumer Credit Card Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	11		9
Financing Receivables, 30 to 59 Days Past Due [Member] | Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	13		13
Financing Receivables, 30 to 59 Days Past Due [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	229		242
Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	157		140
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial And Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	7		11
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Real Estate Mortgage - Owner-Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	8		7
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Real Estate Construction - Owner-Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	0		0
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	15		18
Financing Receivables, 60 to 89 Days Past Due [Member] | Total Commercial Investor Real Estate Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	1		8
Financing Receivables, 60 to 89 Days Past Due [Member] | Commercial Investor Real Estate Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	0		0
Financing Receivables, 60 to 89 Days Past Due [Member] | Total Investor Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	1		8
Financing Receivables, 60 to 89 Days Past Due [Member] | Residential First Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	85		63
Financing Receivables, 60 to 89 Days Past Due [Member] | Home Equity [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	27		22
Financing Receivables, 60 to 89 Days Past Due [Member] | Indirect-vehicles [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	13		14
Financing Receivables, 60 to 89 Days Past Due [Member] | Indirect-other consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	5		3
Financing Receivables, 60 to 89 Days Past Due [Member] | Consumer Credit Card Financing Receivable [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	7		7
Financing Receivables, 60 to 89 Days Past Due [Member] | Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	4		5
Financing Receivables, 60 to 89 Days Past Due [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total 30 plus DPD, Accrual Loans	$ 141		$ 114
[1]	Loans are presented net of unearned income, unamortized discounts and premiums and net deferred loan costs of $43 million and $141 million at December 31, 2017 and 2016, respectively.

Allowance For Credit Losses (Im

Allowance For Credit Losses (Impaired Financing Receivables) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 1,696	$ 2,077
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	138	131
Impaired Financing Receivable, Recorded Investment	[3]	1,558	1,946
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	50	170
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	1,508	1,776
Impaired Financing Receivable, Related Allowance		$ 226	$ 304
Impaired Financing Receivable Coverage Percentage	[4]	21.50%	20.90%
Impaired Financing Receivable, Average Recorded Investment		$ 1,839	$ 1,976	$ 1,848
Impaired Financing Receivable, Interest Income, Accrual Method		53	52	59
Commercial And Industrial [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	634	872
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	88	73
Impaired Financing Receivable, Recorded Investment	[3]	546	799
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	30	126
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	516	673
Impaired Financing Receivable, Related Allowance		$ 122	$ 171
Impaired Financing Receivable Coverage Percentage	[4]	33.10%	28.00%
Impaired Financing Receivable, Average Recorded Investment		$ 747	$ 714	386
Impaired Financing Receivable, Interest Income, Accrual Method		12	6	4
Commercial Real Estate Mortgage - Owner-Occupied [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	223	291
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	20	25
Impaired Financing Receivable, Recorded Investment	[3]	203	266
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	20	39
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	183	227
Impaired Financing Receivable, Related Allowance		$ 46	$ 58
Impaired Financing Receivable Coverage Percentage	[4]	29.60%	28.50%
Impaired Financing Receivable, Average Recorded Investment		$ 226	$ 304	345
Impaired Financing Receivable, Interest Income, Accrual Method		5	5	9
Commercial Real Estate Construction - Owner-Occupied [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	8	5
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	1	1
Impaired Financing Receivable, Recorded Investment	[3]	7	4
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	7	4
Impaired Financing Receivable, Related Allowance		$ 3	$ 2
Impaired Financing Receivable Coverage Percentage	[4]	50.00%	60.00%
Impaired Financing Receivable, Average Recorded Investment		$ 5	$ 3	3
Impaired Financing Receivable, Interest Income, Accrual Method		0	0	0
Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	865	1,168
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	109	99
Impaired Financing Receivable, Recorded Investment	[3]	756	1,069
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	50	165
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	706	904
Impaired Financing Receivable, Related Allowance		$ 171	$ 231
Impaired Financing Receivable Coverage Percentage	[4]	32.40%	28.30%
Impaired Financing Receivable, Average Recorded Investment		$ 978	$ 1,021	734
Impaired Financing Receivable, Interest Income, Accrual Method		17	11	13
Total Commercial Investor Real Estate Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	69	100
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	3	9
Impaired Financing Receivable, Recorded Investment	[3]	66	91
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0	5
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	66	86
Impaired Financing Receivable, Related Allowance		$ 5	$ 12
Impaired Financing Receivable Coverage Percentage	[4]	11.60%	21.00%
Impaired Financing Receivable, Average Recorded Investment		$ 81	$ 120	242
Impaired Financing Receivable, Interest Income, Accrual Method		4	8	11
Total Commercial Investor Real Estate Construction [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	30	16
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	0	0
Impaired Financing Receivable, Recorded Investment	[3]	30	16
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	30	16
Impaired Financing Receivable, Related Allowance		$ 3	$ 1
Impaired Financing Receivable Coverage Percentage	[4]	10.00%	6.30%
Impaired Financing Receivable, Average Recorded Investment		$ 39	$ 30	24
Impaired Financing Receivable, Interest Income, Accrual Method		2	1	1
Total Investor Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	99	116
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	3	9
Impaired Financing Receivable, Recorded Investment	[3]	96	107
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0	5
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	96	102
Impaired Financing Receivable, Related Allowance		$ 8	$ 13
Impaired Financing Receivable Coverage Percentage	[4]	11.10%	19.00%
Impaired Financing Receivable, Average Recorded Investment		$ 120	$ 150	266
Impaired Financing Receivable, Interest Income, Accrual Method		6	9	12
Residential First Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	461	476
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	24	22
Impaired Financing Receivable, Recorded Investment	[3]	437	454
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	437	454
Impaired Financing Receivable, Related Allowance		$ 42	$ 55
Impaired Financing Receivable Coverage Percentage	[4]	14.30%	16.20%
Impaired Financing Receivable, Average Recorded Investment		$ 450	$ 469	477
Impaired Financing Receivable, Interest Income, Accrual Method		15	15	15
Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	261	304
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	2	1
Impaired Financing Receivable, Recorded Investment	[3]	259	303
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	259	303
Impaired Financing Receivable, Related Allowance		$ 5	$ 5
Impaired Financing Receivable Coverage Percentage	[4]	2.70%	2.00%
Impaired Financing Receivable, Average Recorded Investment		$ 280	$ 322	354
Impaired Financing Receivable, Interest Income, Accrual Method		14	16	18
Indirect-vehicles [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]		1
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]		0
Impaired Financing Receivable, Recorded Investment	[3]		1
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]		0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]		1
Impaired Financing Receivable, Related Allowance			$ 0
Impaired Financing Receivable Coverage Percentage	[4]		0.00%
Impaired Financing Receivable, Average Recorded Investment		0	$ 1	1
Impaired Financing Receivable, Interest Income, Accrual Method		0	0	0
Consumer Credit Card Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	1	2
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	0	0
Impaired Financing Receivable, Recorded Investment	[3]	1	2
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	1	2
Impaired Financing Receivable, Related Allowance		$ 0	$ 0
Impaired Financing Receivable Coverage Percentage	[4]	0.00%	0.00%
Impaired Financing Receivable, Average Recorded Investment		$ 2	$ 2	2
Impaired Financing Receivable, Interest Income, Accrual Method		0	0	0
Other Consumer [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	9	10
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	0	0
Impaired Financing Receivable, Recorded Investment	[3]	9	10
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	9	10
Impaired Financing Receivable, Related Allowance		$ 0	$ 0
Impaired Financing Receivable Coverage Percentage	[4]	0.00%	0.00%
Impaired Financing Receivable, Average Recorded Investment		$ 9	$ 11	848
Impaired Financing Receivable, Interest Income, Accrual Method		1	1	1
Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	732	793
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	26	23
Impaired Financing Receivable, Recorded Investment	[3]	706	770
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	706	770
Impaired Financing Receivable, Related Allowance		$ 47	$ 60
Impaired Financing Receivable Coverage Percentage	[4]	10.00%	10.50%
Impaired Financing Receivable, Average Recorded Investment		$ 741	$ 805	14
Impaired Financing Receivable, Interest Income, Accrual Method		30	32	$ 34
Non-Accrual [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	679	991
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	109	108
Impaired Financing Receivable, Recorded Investment	[3]	570	883
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	49	170
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	521	713
Impaired Financing Receivable, Related Allowance		$ 149	$ 202
Impaired Financing Receivable Coverage Percentage	[4]	38.00%	31.30%
Non-Accrual [Member] | Commercial And Industrial [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 480	$ 685
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	80	72
Impaired Financing Receivable, Recorded Investment	[3]	400	613
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	29	126
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	371	487
Impaired Financing Receivable, Related Allowance		$ 103	$ 138
Impaired Financing Receivable Coverage Percentage	[4]	38.10%	30.70%
Non-Accrual [Member] | Commercial Real Estate Mortgage - Owner-Occupied [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 133	$ 231
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	15	21
Impaired Financing Receivable, Recorded Investment	[3]	118	210
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	20	39
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	98	171
Impaired Financing Receivable, Related Allowance		$ 38	$ 53
Impaired Financing Receivable Coverage Percentage	[4]	39.80%	32.00%
Non-Accrual [Member] | Commercial Real Estate Construction - Owner-Occupied [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 7	$ 4
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	1	1
Impaired Financing Receivable, Recorded Investment	[3]	6	3
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	6	3
Impaired Financing Receivable, Related Allowance		$ 3	$ 2
Impaired Financing Receivable Coverage Percentage	[4]	57.10%	75.00%
Non-Accrual [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 620	$ 920
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	96	94
Impaired Financing Receivable, Recorded Investment	[3]	524	826
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	49	165
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	475	661
Impaired Financing Receivable, Related Allowance		$ 144	$ 193
Impaired Financing Receivable Coverage Percentage	[4]	38.70%	31.20%
Non-Accrual [Member] | Total Commercial Investor Real Estate Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 6	$ 18
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	1	1
Impaired Financing Receivable, Recorded Investment	[3]	5	17
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0	5
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	5	12
Impaired Financing Receivable, Related Allowance		$ 2	$ 5
Impaired Financing Receivable Coverage Percentage	[4]	50.00%	33.30%
Non-Accrual [Member] | Total Commercial Investor Real Estate Construction [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 1
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	0
Impaired Financing Receivable, Recorded Investment	[3]	1
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	1
Impaired Financing Receivable, Related Allowance		$ 0
Impaired Financing Receivable Coverage Percentage	[4]	0.00%
Non-Accrual [Member] | Total Investor Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 7	$ 18
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	1	1
Impaired Financing Receivable, Recorded Investment	[3]	6	17
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0	5
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	6	12
Impaired Financing Receivable, Related Allowance		$ 2	$ 5
Impaired Financing Receivable Coverage Percentage	[4]	42.90%	33.30%
Non-Accrual [Member] | Residential First Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 42	$ 41
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	11	12
Impaired Financing Receivable, Recorded Investment	[3]	31	29
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	31	29
Impaired Financing Receivable, Related Allowance		$ 3	$ 4
Impaired Financing Receivable Coverage Percentage	[4]	33.30%	39.00%
Non-Accrual [Member] | Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 10	$ 12
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	1	1
Impaired Financing Receivable, Recorded Investment	[3]	9	11
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	9	11
Impaired Financing Receivable, Related Allowance		$ 0	$ 0
Impaired Financing Receivable Coverage Percentage	[4]	10.00%	8.30%
Non-Accrual [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 52	$ 53
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	12	13
Impaired Financing Receivable, Recorded Investment	[3]	40	40
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	40	40
Impaired Financing Receivable, Related Allowance		$ 3	$ 4
Impaired Financing Receivable Coverage Percentage	[4]	28.80%	32.10%
Accrual [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 1,017	$ 1,086
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	29	23
Impaired Financing Receivable, Recorded Investment	[3]	988	1,063
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	1
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	987
Impaired Financing Receivable, Related Allowance		$ 77	$ 102
Impaired Financing Receivable Coverage Percentage	[4]	10.40%	11.50%
Accrual [Member] | Commercial And Industrial [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 154	$ 187
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	8	1
Impaired Financing Receivable, Recorded Investment	[3]	146	186
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	1
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	145
Impaired Financing Receivable, Related Allowance		$ 19	$ 33
Impaired Financing Receivable Coverage Percentage	[4]	17.50%	18.20%
Accrual [Member] | Commercial Real Estate Mortgage - Owner-Occupied [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 90	$ 60
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	5	4
Impaired Financing Receivable, Recorded Investment	[3]	85	56
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	85
Impaired Financing Receivable, Related Allowance		$ 8	$ 5
Impaired Financing Receivable Coverage Percentage	[4]	14.40%	15.00%
Accrual [Member] | Commercial Real Estate Construction - Owner-Occupied [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 1	$ 1
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	0	0
Impaired Financing Receivable, Recorded Investment	[3]	1	1
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	1
Impaired Financing Receivable, Related Allowance		$ 0	$ 0
Impaired Financing Receivable Coverage Percentage	[4]	0.00%	0.00%
Accrual [Member] | Commercial Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 245	$ 248
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	13	5
Impaired Financing Receivable, Recorded Investment	[3]	232	243
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	1
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	231
Impaired Financing Receivable, Related Allowance		$ 27	$ 38
Impaired Financing Receivable Coverage Percentage	[4]	16.30%	17.30%
Accrual [Member] | Total Commercial Investor Real Estate Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 63	$ 82
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	2	8
Impaired Financing Receivable, Recorded Investment	[3]	61	74
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	61
Impaired Financing Receivable, Related Allowance		$ 3	$ 7
Impaired Financing Receivable Coverage Percentage	[4]	7.90%	18.30%
Accrual [Member] | Total Commercial Investor Real Estate Construction [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 29	$ 16
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	0	0
Impaired Financing Receivable, Recorded Investment	[3]	29	16
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	29
Impaired Financing Receivable, Related Allowance		$ 3	$ 1
Impaired Financing Receivable Coverage Percentage	[4]	10.30%	6.30%
Accrual [Member] | Total Investor Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 92	$ 98
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	2	8
Impaired Financing Receivable, Recorded Investment	[3]	90	90
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	90
Impaired Financing Receivable, Related Allowance		$ 6	$ 8
Impaired Financing Receivable Coverage Percentage	[4]	8.70%	16.30%
Accrual [Member] | Residential First Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 419	$ 435
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	13	10
Impaired Financing Receivable, Recorded Investment	[3]	406	425
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	406
Impaired Financing Receivable, Related Allowance		$ 39	$ 51
Impaired Financing Receivable Coverage Percentage	[4]	12.40%	14.00%
Accrual [Member] | Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 251	$ 292
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	1	0
Impaired Financing Receivable, Recorded Investment	[3]	250	292
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	250
Impaired Financing Receivable, Related Allowance		$ 5	$ 5
Impaired Financing Receivable Coverage Percentage	[4]	2.40%	1.70%
Accrual [Member] | Indirect-vehicles [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]		$ 1
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]		0
Impaired Financing Receivable, Recorded Investment	[3]		1
Impaired Financing Receivable, Related Allowance			$ 0
Impaired Financing Receivable Coverage Percentage	[4]		0.00%
Accrual [Member] | Consumer Credit Card Financing Receivable [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 1	$ 2
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	0	0
Impaired Financing Receivable, Recorded Investment	[3]	1	2
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	1
Impaired Financing Receivable, Related Allowance		$ 0	$ 0
Impaired Financing Receivable Coverage Percentage	[4]	0.00%	0.00%
Accrual [Member] | Other Consumer [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 9	$ 10
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	0	0
Impaired Financing Receivable, Recorded Investment	[3]	9	10
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	9
Impaired Financing Receivable, Related Allowance		$ 0	$ 0
Impaired Financing Receivable Coverage Percentage	[4]	0.00%	0.00%
Accrual [Member] | Consumer Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	[1]	$ 680	$ 740
Impaired Financing Receivable Chargeoffs And Payments Applied	[2]	14	10
Impaired Financing Receivable, Recorded Investment	[3]	666	730
Impaired Financing Receivable, with No Related Allowance, Recorded Investment	[3]	0
Impaired Financing Receivable, with Related Allowance, Recorded Investment	[3]	666
Impaired Financing Receivable, Related Allowance		$ 44	$ 56
Impaired Financing Receivable Coverage Percentage	[4]	8.50%	8.90%
[1]	Unpaid principal balance represents the contractual obligation due from the customer and includes the net book value plus charge-offs and payments applied.
[2]	Charge-offs and payments applied represents cumulative partial charge-offs taken, as well as interest payments received that have been applied against the outstanding principal balance.
[3]	Book value represents the unpaid principal balance less charge-offs and payments applied; it is shown before any allowance for loan losses.
[4]	Coverage % represents charge-offs and payments applied plus the related allowance as a percent of the unpaid principal balance.

Allowance For Credit Losses (Lo

Allowance For Credit Losses (Loans By Class Modified In TDR) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)obligor	Dec. 31, 2016USD ($)Obligatorobligor
Financing Receivable, Modifications [Line Items]
Number of Obligors | obligor	850	1,200
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 830	$ 811
Increase in Allowance at Modification	$ 23	$ 23
Commercial And Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Obligors | obligor	134	184
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 493	$ 509
Increase in Allowance at Modification	$ 10	$ 12
Commercial Real Estate Mortgage - Owner-Occupied [Member]
Financing Receivable, Modifications [Line Items]
Number of Obligors | obligor	118	117
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 110	$ 98
Increase in Allowance at Modification	$ 3	$ 2
Commercial Real Estate Construction - Owner-Occupied [Member]
Financing Receivable, Modifications [Line Items]
Number of Obligors	3	1
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 2	$ 1
Increase in Allowance at Modification	$ 0	$ 0
Commercial investor real estate mortgage [Member]
Financing Receivable, Modifications [Line Items]
Number of Obligors | obligor	42	80
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 104	$ 96
Increase in Allowance at Modification	$ 3	$ 2
Commercial Investor Real Estate Construction [Member]
Financing Receivable, Modifications [Line Items]
Number of Obligors | obligor	5	9
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 70	$ 43
Increase in Allowance at Modification	$ 2	$ 1
Residential First Mortgage [Member]
Financing Receivable, Modifications [Line Items]
Number of Obligors | obligor	209	231
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 39	$ 46
Increase in Allowance at Modification	$ 5	$ 6
Home Equity [Member]
Financing Receivable, Modifications [Line Items]
Number of Obligors | obligor	116	300
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 9	$ 15
Increase in Allowance at Modification	$ 0	$ 0
Consumer Credit Card Financing Receivable [Member]
Financing Receivable, Modifications [Line Items]
Number of Obligors | obligor	68	88
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 1	$ 1
Increase in Allowance at Modification	$ 0	$ 0
Indirect-vehicles and other consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Obligors | obligor	155	190
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 2	$ 2
Increase in Allowance at Modification	$ 0	$ 0
Commercial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Obligors | obligor	255	302
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 605	$ 608
Increase in Allowance at Modification	$ 13	$ 14
Total Investor Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Obligors | obligor	47	89
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 174	$ 139
Increase in Allowance at Modification	$ 5	$ 3
Consumer Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Obligors | obligor	548	809
Financing Receivable, Modifications, Post-Modification Recorded Investment	$ 51	$ 64
Increase in Allowance at Modification	$ 5	$ 6

Allowance For Credit Losses (80

Allowance For Credit Losses (Loans Modified In Past Twelve Months Which Subsequently Defaulted) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Modifications [Line Items]
Defaulted during period where modified in a TDR, twelve months prior to modification	$ 21	$ 58
Commercial And Industrial [Member]
Financing Receivable, Modifications [Line Items]
Defaulted during period where modified in a TDR, twelve months prior to modification	10	28
Commercial Real Estate Mortgage - Owner-Occupied [Member]
Financing Receivable, Modifications [Line Items]
Defaulted during period where modified in a TDR, twelve months prior to modification	1	3
Commercial investor real estate mortgage [Member]
Financing Receivable, Modifications [Line Items]
Defaulted during period where modified in a TDR, twelve months prior to modification	0	3
Commercial Investor Real Estate Construction [Member]
Financing Receivable, Modifications [Line Items]
Defaulted during period where modified in a TDR, twelve months prior to modification	0	1
Residential First Mortgage [Member]
Financing Receivable, Modifications [Line Items]
Defaulted during period where modified in a TDR, twelve months prior to modification	9	21
Home Equity [Member]
Financing Receivable, Modifications [Line Items]
Defaulted during period where modified in a TDR, twelve months prior to modification	1	2
Commercial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Defaulted during period where modified in a TDR, twelve months prior to modification	11	31
Total Investor Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Defaulted during period where modified in a TDR, twelve months prior to modification	0	4
Consumer Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Defaulted during period where modified in a TDR, twelve months prior to modification	$ 10	$ 23

Servicing of Financial Assets (

Servicing of Financial Assets (Analysis Of Residential MSRs Under The Fair Value Measurement Method) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Servicing Asset at Fair Value, Amount [Roll Forward]
Carrying Value, beginning of period		$ 324	$ 252	$ 257
Additions		64	108	36
Increase (decrease) in fair value, due to change in valuation inputs or assumptions	[1]	(8)	4	(2)
Increase (decrease) in fair value, economic amortization associated with borrower repayments	[1]	(44)	(40)	(39)
Carrying value, end of period		$ 336	$ 324	$ 252
[1]	"Economic amortization associated with borrower repayments" includes both total loan payoffs as well as partial paydowns.

Servicing of Financial Assets82

Servicing of Financial Assets (Data And Assumptions Used In The Fair Value Calculation As Well As The Valuation's Sensitivity To Rate Fluctuations Related To Mortgage Servicing Rights) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)basis_point	Dec. 31, 2016USD ($)basis_point
Servicing Assets at Fair Value [Line Items]
Estimated Fair Value of FNMA DUS Loss Share Guarantee	$ 4	$ 4
Unpaid principal balance	$ 32,076	$ 31,335
Weighted-average CPR (%)	9.90%	7.60%
Estimated impact on fair value of a 10% increase	$ (22)	$ (19)
Estimated impact on fair value of a 20% increase	$ (39)	$ (34)
Option-adjusted spread (basis points) | basis_point	861	1,054
Estimated impact on fair value of a 10% increase	$ (11)	$ (13)
Estimated impact on fair value of a 20% increase	$ (22)	$ (27)
Weighted-Average Coupon Interest Rate	4.10%	4.20%
Weighted-average remaining maturity (months)	281 months	281 months
Weighted-average servicing fee (basis points) | basis_point	27.4	27.5

Servicing of Financial Assets83

Servicing of Financial Assets (Schedule Of Fees Resulting From The Servicing Of Residential Mortgage Loans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Transfers and Servicing of Financial Assets [Abstract]
Servicing related fees and other ancillary income	$ 96	$ 86	$ 82

Servicing of Financial Assets84

Servicing of Financial Assets (Narrative) (Details) - USD ($) $ in Millions	Apr. 28, 2017	Nov. 30, 2016	Sep. 01, 2016	Feb. 29, 2016	Apr. 30, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jul. 18, 2014
Servicing Assets at Fair Value [Line Items]
Unpaid Principal Balance of Outstanding Underlying MSRs Purchased	$ 2,700	$ 2,200	$ 2,800	$ 2,600	$ 380
Payments to Acquire Mortgage Servicing Rights (MSR)	$ 30	$ 23	$ 22	$ 24	$ 4	$ 5	$ 18	$ 41	$ 64	$ 4
Unpaid principal balance						32,076	31,335	32,076	31,335
Loss Share Guarantee						4	4	4	4
Licensing Agreements [Member]
Servicing Assets at Fair Value [Line Items]
Other Intangible Assets, Net											$ 15
DUS Portfolio [Member]
Servicing Assets at Fair Value [Line Items]
Unpaid principal balance						2,900	1,800	2,900	1,800		1,000
Commercial Real Estate [Member]
Servicing Assets at Fair Value [Line Items]
Servicing Asset at Amortized Cost						48	30	48	30		12
Loss Share Guarantee						$ 4	$ 4	$ 4	$ 4		$ 4

Other Earning Assets (Schedule

Other Earning Assets (Schedule Of Investments in Federal Reserve Bank Stock And Federal Home Loan Bank Stock) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Federal Home Loan Bank Stock and Federal Reserve Bank Stock [Abstract]
Federal Reserve Bank Stock	$ 492	$ 494
Federal Home Loan Bank Stock	$ 192	$ 196

Other Earning Assets (Schedul86

Other Earning Assets (Schedule of Property Subject to or Available for Operating Lease) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease, Net	$ 489	$ 688
Other Machinery and Equipment [Member] | Property Subject to Operating Lease [Member]
Property Subject to or Available for Operating Lease [Line Items]
Property Subject to or Available for Operating Lease, Gross	685	818
Property Subject to or Available for Operating Lease, Accumulated Depreciation	(196)	(130)
Property Subject to or Available for Operating Lease, Net	$ 489	$ 688

Other Earning Assets (Schedul87

Other Earning Assets (Schedule of Future Minimum Rental Payments Receivable for Operating Leases) (Details) $ in Millions	Dec. 31, 2017USD ($)
Operating Leases, Future Minimum Payments Receivable [Abstract]
Operating Leases, Future Minimum Payments Receivable, Next Twelve Months	$ 74
Operating Leases, Future Minimum Payments, Receivable in Two Years	59
Operating Leases, Future Minimum Payments, Receivable in Three Years	44
Operating Leases, Future Minimum Payments, Receivable in Four Years	30
Operating Leases, Future Minimum Payments, Receivable in Five Years	17
Operating Leases, Future Minimum Payments, Receivable Thereafter	20
Operating Leases, Future Minimum Payments Receivable	$ 244

Premises and Equipment (Schedul

Premises and Equipment (Schedule of Premises and Equipment) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 4,478	$ 4,443
Accumulated depreciation and amortization	(2,414)	(2,347)
Premises and equipment, net	2,064	2,096
Land
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	484	490
Premises and improvements
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	1,751	1,730
Furniture and equipment
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	982	1,025
Software
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	624	597
Leasehold improvements
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	388	387
Construction in progress
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 249	$ 214

Intangible Assets (Schedule Of

Intangible Assets (Schedule Of Goodwill By Segment) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Goodwill [Line Items]
Goodwill	$ 4,904	$ 4,904
Corporate Bank [Member]
Goodwill [Line Items]
Goodwill	2,474	2,474
Consumer Bank [Member]
Goodwill [Line Items]
Goodwill	1,978	1,978
Wealth Management [Member]
Goodwill [Line Items]
Goodwill	$ 452	$ 452

Intangible Assets (Schedule O90

Intangible Assets (Schedule Of Assumptions Used In Estimating Fair Value) (Details)		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016
Corporate Bank [Member]
Intangible Assets By Major Class [Line Items]
Discount Rate Used In Income Approach		11.25%	10.00%
Public Company Method Market Multiplier	[1]	1.8	1.5
Transaction Method Market Multiplier	[2]	1.9	1.9
Consumer Bank [Member]
Intangible Assets By Major Class [Line Items]
Discount Rate Used In Income Approach		11.00%	10.25%
Public Company Method Market Multiplier	[1]	2	1.9
Transaction Method Market Multiplier	[2]	2.6	1.9
Wealth Management [Member]
Intangible Assets By Major Class [Line Items]
Discount Rate Used In Income Approach		11.25%	11.50%
Public Company Method Market Multiplier	[1]	18.8	14.6
Transaction Method Market Multiplier	[2]	24.2	23.5
[1]	For the Corporate Bank and Consumer Bank reporting units, these multipliers are applied to tangible book value. For the Wealth Management reporting unit, this multiplier is applied to earnings. In addition to the multipliers, a 10 percent control premium was assumed for the Corporate Bank reporting unit, and a 25 percent control premium was assumed for the Consumer Bank and the Wealth Management reporting units based on current market factors. Because the control premium considers potential revenue synergies and cost savings for similar financial services transactions, reporting units operating in businesses that have greater barriers to entry tend to have greater control premiums.
[2]	For the Corporate Bank and Consumer Bank reporting units, these multipliers are applied to tangible book value. For the Wealth Management reporting unit, this multiplier is applied to earnings.

Intangible Assets (Schedule o91

Intangible Assets (Schedule of Other Intangible Assets) (Details) - USD ($) $ in Millions		Dec. 31, 2017	Dec. 31, 2016
Other Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross		$ 1,280	$ 1,280
Finite-Lived Intangible Assets, Accumulated Amortization		1,121	1,077
Finite-Lived Intangible Assets, Net		177	221
Core Deposits [Member]
Other Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross		1,011	1,011
Finite-Lived Intangible Assets, Accumulated Amortization		950	932
Finite-Lived Intangible Assets, Net		61	79
Purchased Credit Card Relationships [Member]
Other Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross		175	175
Finite-Lived Intangible Assets, Accumulated Amortization		116	102
Finite-Lived Intangible Assets, Net		59	73
Customer Relationships [Member]
Other Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross		75	75
Finite-Lived Intangible Assets, Accumulated Amortization		43	33
Finite-Lived Intangible Assets, Net		32	42
Other Intangible Assets [Member]
Other Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross		19	19
Finite-Lived Intangible Assets, Accumulated Amortization		12	10
Finite-Lived Intangible Assets, Net	[1]	7	9
Fannie Mae DUS License [Member]
Other Intangible Assets [Line Items]
Other Intangible Assets, Net	[2]	15	15
Other Intangible Assets [Member]
Other Intangible Assets [Line Items]
Other Intangible Assets, Net	[3]	$ 3	$ 3
[1]	Includes intangible assets related to acquired trust services, trade names and intellectual property.
[2]	The DUS license is a non-amortizing intangible asset.
[3]	Includes non-amortizing intangible assets related to other acquired trust services.

Intangible Assets (Aggregate Am

Intangible Assets (Aggregate Amount of Amortization Expense) (Details) $ in Millions	Dec. 31, 2017USD ($)
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	$ 39
Finite-Lived Intangible Assets, Amortization Expense, Year Two	32
Finite-Lived Intangible Assets, Amortization Expense, Year Three	26
Finite-Lived Intangible Assets, Amortization Expense, Year Four	21
Finite-Lived Intangible Assets, Amortization Expense, Year Five	$ 17

Intangible Assets (Narrative) (

Intangible Assets (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Intangible Assets [Line Items]
Goodwill, Impairment Loss	$ 0	$ 0	$ 0
Impairment of Intangible Assets (Excluding Goodwill)	$ 0	$ 0	$ 0
Corporate Bank [Member]
Intangible Assets [Line Items]
Fair Value Measurements Intangible Assets Control Premium Percent	10.00%	10.00%
Wealth Management [Member]
Intangible Assets [Line Items]
Fair Value Measurements Intangible Assets Control Premium Percent	25.00%	25.00%
Consumer Bank [Member]
Intangible Assets [Line Items]
Fair Value Measurements Intangible Assets Control Premium Percent	25.00%	25.00%
Minimum [Member]
Intangible Assets [Line Items]
Finite Lived Intangible Assets, Useful Life	2 years
Maximum [Member]
Intangible Assets [Line Items]
Finite Lived Intangible Assets, Useful Life	15 years

Deposits (Schedule of Interest-

Deposits (Schedule of Interest-Bearing Deposits) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Deposits [Abstract]
Savings	$ 8,413	$ 7,840
Interest-bearing transaction	20,161	20,259
Money market—domestic	25,306	27,293
Money market—foreign	23	186
Time deposits	6,859	7,183
Interest-bearing customer deposits	60,762	62,761
Corporate treasury time deposits	0	228
Interest-bearing	$ 60,762	$ 62,989

Deposits (Schedule of Aggregate

Deposits (Schedule of Aggregate Amount of Maturities of All Time Deposits) (Details) $ in Millions	Dec. 31, 2017USD ($)
Deposits [Abstract]
Time Deposit Maturities, Next Twelve Months	$ 3,207
Time Deposit Maturities, Year Two	940
Time Deposit Maturities, Year Three	1,237
Time Deposit Maturities, Year Four	893
Time Deposit Maturities, Year Five	345
Time Deposit Maturities, after Year Five	237
Aggregate amount of maturities of time deposits	$ 6,859

Deposits (Narrative) (Details)

Deposits (Narrative) (Details) - USD ($) $ in Billions	Dec. 31, 2017	Dec. 31, 2016
Deposits [Abstract]
Time Deposits, $250,000 or More	$ 1.3	$ 1.2

Short-Term Borrowings (Schedule

Short-Term Borrowings (Schedule Of Short-Term Borrowings) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Short-term Debt [Line Items]
Short-term borrowings	$ 500	$ 0
Company Funding Sources [Member] | Federal Home Loan Bank Advances [Member]
Short-term Debt [Line Items]
Short-term borrowings	$ 500	$ 0

Long-Term Borrowings (Schedule

Long-Term Borrowings (Schedule of Long-Term Borrowings) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long-term borrowings	$ 8,132	$ 7,763
Subordinated Debt [Member] | Elimination of Three Point Eight Zero Percent Affiliate Subordinated Notes Due February Two Thousand Twenty Five [Member] [Domain]
Debt Instrument [Line Items]
Long-term borrowings	0	(150)
Parent Company [Member]
Debt Instrument [Line Items]
Long-term borrowings	2,702	1,728
Parent Company [Member] | Senior Notes [Member] | Two Percent Senior Notes Due May 2018 [Member]
Debt Instrument [Line Items]
Long-term borrowings	101	100
Parent Company [Member] | Senior Notes [Member] | Three Point Two Zero Percent Senior Notes Due February 2021 [Member]
Debt Instrument [Line Items]
Long-term borrowings	1,101	1,102
Parent Company [Member] | Senior Notes [Member] | Two Point Seven Five Percent Senior Notes Due August 2022 [Member]
Debt Instrument [Line Items]
Long-term borrowings	995	0
Parent Company [Member] | Subordinated Debt [Member] | Seven Point Seven Five Percent Subordinated Notes Due September Two Thousand Twenty Four [Member]
Debt Instrument [Line Items]
Long-term borrowings	100	100
Parent Company [Member] | Subordinated Debt [Member] | Six Point Seven Five Percent Subordinated Debentures Due November Two Thousand Twenty Five [Member]
Debt Instrument [Line Items]
Long-term borrowings	158	159
Parent Company [Member] | Subordinated Debt [Member] | Seven Point Three Seven Five Percent Subordinated Notes Due December Two Thousand Thirty Seven [Member]
Debt Instrument [Line Items]
Long-term borrowings	297	297
Parent Company [Member] | Valuation Adjustments On Hedged Long Term Debt [Member]
Debt Instrument [Line Items]
Long-term borrowings	(50)	(30)
Regions Bank [Member]
Debt Instrument [Line Items]
Long-term borrowings	5,430	6,185
Regions Bank [Member] | Senior Notes [Member] | Two Point Two Five Percent Senior Notes Due September Two Thousand Eighteen [Member]
Debt Instrument [Line Items]
Long-term borrowings	749	748
Regions Bank [Member] | Subordinated Debt [Member] | Seven Point Five Zero Percent Subordinated Notes Due May Two Thousand Eighteen [Member]
Debt Instrument [Line Items]
Long-term borrowings	500	499
Regions Bank [Member] | Subordinated Debt [Member] | Six Point Four Five Percent Subordinated Notes Due June Two Thousand Thirty Seven [Member]
Debt Instrument [Line Items]
Long-term borrowings	495	495
Regions Bank [Member] | Subordinated Debt [Member] | Three Point Eight Zero Percent Affiliate Subordinated Notes Due February Two Thousand Twenty Five [Member] [Domain]
Debt Instrument [Line Items]
Long-term borrowings	0	150
Regions Bank [Member] | Federal Home Loan Bank Advances [Member]
Debt Instrument [Line Items]
Long-term borrowings	3,653	4,254
Regions Bank [Member] | Other Long Term Debt [Member]
Debt Instrument [Line Items]
Long-term borrowings	35	40
Regions Bank [Member] | Valuation Adjustments On Hedged Long Term Debt [Member]
Debt Instrument [Line Items]
Long-term borrowings	$ (2)	$ (1)

Long-Term Borrowings (Schedul99

Long-Term Borrowings (Schedule of Maturities of Long-Term Borrowings) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Schedule of Maturities of Long-Term Debt [Line Items]
Long-term borrowings	$ 8,132	$ 7,763
Parent Company [Member]
Schedule of Maturities of Long-Term Debt [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	101
Long-term Debt, Maturities, Repayments of Principal in Year Two	0
Long-term Debt, Maturities, Repayments of Principal in Year Three	0
Long-term Debt, Maturities, Repayments of Principal in Year Four	1,066
Long-term Debt, Maturities, Repayments of Principal in Year Five	980
Long-term Debt, Maturities, Repayments of Principal after Year Five	555
Long-term borrowings	2,702	1,728
Regions Bank [Member]
Schedule of Maturities of Long-Term Debt [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	4,899
Long-term Debt, Maturities, Repayments of Principal in Year Two	4
Long-term Debt, Maturities, Repayments of Principal in Year Three	30
Long-term Debt, Maturities, Repayments of Principal in Year Four	1
Long-term Debt, Maturities, Repayments of Principal in Year Five	0
Long-term Debt, Maturities, Repayments of Principal after Year Five	496
Long-term borrowings	$ 5,430	$ 6,185

Long-Term Borrowings (Narrative

Long-Term Borrowings (Narrative) (Details) $ in Millions	Jan. 23, 2018USD ($)	Aug. 14, 2017USD ($)	Dec. 31, 2017USD ($)agreement	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Total Borrowing Capacity with the FHLB			$ 17,200
Debt, Weighted Average Interest Rate			3.00%	2.40%	3.10%
Subordinated Debt [Member]
Debt Instrument [Line Items]
Number Of Issuances Of Debt | agreement			5
Proceeds from Issuance of Long-term Debt			$ 1,600
Federal Home Loan Bank Advances [Member]
Debt Instrument [Line Items]
FHLB Advances Weighted Average Interest Rate			1.40%	0.80%	0.70%
Debt Maturity Period In Years Of Other Fhlb Advances With Maturities Minimum			1 year
Debt Maturity Period In Years Of Other Fhlb Advances With Maturities Maximum			13 years
Debt maturity in Years of Other FHLB Advances With Maturities Weighted Average			9 months 27 days
Two Point Seven Five Percent Senior Notes Due August 2022 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Proceeds from Issuance of Senior Long-term Debt		$ 1,000
Minimum [Member] | Subordinated Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			6.45%
Maximum [Member] | Subordinated Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			7.75%
Subsequent Event [Member] | Two Point Seven Five Percent Senior Notes Due April 2021 [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Proceeds from Issuance of Senior Long-term Debt	$ 550
Subsequent Event [Member] | Plus 3-Month LIBOR plus 38 points[Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Proceeds from Issuance of Senior Long-term Debt	$ 350

Regulatory Capital Requireme101

Regulatory Capital Requirements and Restrictions (Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations) (Details) - Transitional Basis Basel III Regulatory Capital Rules [Member] - USD ($) $ in Millions		Dec. 31, 2017		Dec. 31, 2016
Regions Financial Corporation [Member]
Basel III Common Equity Tier 1 Capital
Basel III common equity Tier 1, Amount	[2]	$ 11,152	[1]	$ 11,481
Basel III common equity Tier 1, Ratio	[2]	11.05%	[1]	11.21%
Basel III common equity Tier 1, Minimum Requirement		4.50%		4.50%
Tier One Risk Based Capital
Tier 1 Capital, Amount	[2]	$ 11,964	[1]	$ 12,277
Tier 1 Capital, Ratio	[2]	11.86%	[1]	11.98%
Tier 1 Capital, Minimum Requirement		6.00%		6.00%
Tier 1 Capital, To Be Well Capitalized		6.00%		6.00%
Total Capital
Total Capital, Amount	[2]	$ 13,903	[1]	$ 14,501
Total Capital, Ratio	[2]	13.78%	[1]	14.15%
Total Capital, Minimum Requirement		8.00%		8.00%
Total Capital, To Be Well Capitalized		10.00%		10.00%
Leverage Capital
Leverage, Amount	[2]	$ 11,964	[1]	$ 12,277
Leverage, Ratio	[2]	10.01%	[1]	10.20%
Leverage, Minimum Requirement		4.00%		4.00%
Regions Bank [Member]
Basel III Common Equity Tier 1 Capital
Basel III common equity Tier 1, Amount	[2]	$ 12,560	[1]	$ 12,404
Basel III common equity Tier 1, Ratio	[2]	12.49%	[1]	12.14%
Basel III common equity Tier 1, Minimum Requirement		4.50%		4.50%
Basel III common equity Tier 1, To Be Well Capitalized		6.50%		6.50%
Tier One Risk Based Capital
Tier 1 Capital, Amount	[2]	$ 12,560	[1]	$ 12,404
Tier 1 Capital, Ratio	[2]	12.49%	[1]	12.14%
Tier 1 Capital, Minimum Requirement		6.00%		6.00%
Tier 1 Capital, To Be Well Capitalized		8.00%		8.00%
Total Capital
Total Capital, Amount	[2]	$ 14,042	[1]	$ 14,311
Total Capital, Ratio	[2]	13.97%	[1]	14.00%
Total Capital, Minimum Requirement		8.00%		8.00%
Total Capital, To Be Well Capitalized		10.00%		10.00%
Leverage Capital
Leverage, Amount	[2]	$ 12,560	[1]	$ 12,404
Leverage, Ratio	[2]	10.54%	[1]	10.34%
Leverage, Minimum Requirement		4.00%		4.00%
Leverage, To Be Well Capitalized		5.00%		5.00%
[1]	The 2017 Basel III CET1 capital, Tier 1 capital, Total capital, and Leverage capital ratios are estimated.
[2]	The 2017 and 2016 capital ratios were calculated at different points of the phase-in period under the Basel III Rules and therefore are not directly comparable.

Stockholders' Equity and Acc102

Stockholders' Equity and Accumulated Other Comprehensive Income (Loss) (Preferred Stock Issuances) (Details) - USD ($) $ in Millions		12 Months Ended	120 Months Ended
		Dec. 31, 2017	Sep. 15, 2024	Dec. 31, 2016
Class of Stock [Line Items]
Preferred Stock, Liquidation Preference, Value		$ 1,000
Preferred Stock, Carrying Amount		$ 820		$ 820
Series A Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Dividend Rate, Percentage		6.375%
Preferred Stock, Liquidation Preference, Value		$ 500
Preferred Stock, Carrying Amount		$ 387		387
Series B Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Dividend Rate, Percentage	[1]	6.375%
Preferred Stock, Liquidation Preference, Value		$ 500
Preferred Stock, Carrying Amount		$ 433		$ 433
Scenario, Forecast [Member] | Series B Preferred Stock Dividend Scenario 1 [Member]
Class of Stock [Line Items]
Preferred Stock, Dividend Rate, Percentage			6.375%
Plus 3-Month LIBOR [Member] | Scenario, Forecast [Member] | Series B Preferred Stock Dividend Scenario 2 [Member]
Class of Stock [Line Items]
Preferred Stock, Dividend Rate, Basis Spread on Variable Rate, Percentage			3.536%
[1]	Dividends, if declared, will be paid quarterly at an annual rate equal to (i) for each period beginning prior to September 15, 2024, 6.375%, and (ii) for each period beginning on or after September 15, 2024, three-month LIBOR plus 3.536%.

Stockholders' Equity and Acc103

Stockholders' Equity and Accumulated Other Comprehensive Income (Loss) (Schedule Of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start	$ (550)	$ (380)	$ (238)
Other comprehensive income (loss), net of tax	(66)	(170)	(142)
Reclassification of the Tax Reform related revaluation of deferred tax items within accumulated other comprehensive income	(133)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End	(749)	(550)	(380)
Accumulated Net Unrealized Loss on Held To Maturity Securities [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start	(33)	(47)	(55)
Other comprehensive income (loss), net of tax	6	14	8
Reclassification of the Tax Reform related revaluation of deferred tax items within accumulated other comprehensive income	(6)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End	(33)	(33)	(47)
Accumulated Net Unrealized Securities Available For Sale Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start	(106)	(10)	175
Other comprehensive income (loss), net of tax	(12)	(96)	(185)
Reclassification of the Tax Reform related revaluation of deferred tax items within accumulated other comprehensive income	(35)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End	(153)	(106)	(10)
Accumulated Net Gain (Loss) from Derivative Instruments Designated as Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start	11	75	33
Other comprehensive income (loss), net of tax	(51)	(64)	42
Reclassification of the Tax Reform related revaluation of deferred tax items within accumulated other comprehensive income	(11)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End	(51)	11	75
Accumulated Defined Benefit Pension Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period Start	(422)	(398)	(391)
Other comprehensive income (loss), net of tax	(9)	(24)	(7)
Reclassification of the Tax Reform related revaluation of deferred tax items within accumulated other comprehensive income	(81)
Accumulated Other Comprehensive Income (Loss), Net of Tax, Period End	$ (512)	$ (422)	$ (398)

Stockholders' Equity and Acc104

Stockholders' Equity and Accumulated Other Comprehensive Income (Loss) (Reclassification From Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net interest income and other financing income		$ 3,540	$ 3,398	$ 3,307
Securities gains, net		22	6	29
Salaries and employee benefits		(1,954)	(1,913)	(1,883)
Income tax (expense) benefits	[1],[2]	(614)	(514)	(455)
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income (loss)	[3]	28	57	75
Accumulated Net Unrealized Loss on Held To Maturity Securities [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net interest income and other financing income	[3]	(10)	(22)	(14)
Income tax (expense) benefits	[3]	4	8	6
Net income (loss)	[3]	(6)	(14)	(8)
Accumulated Net Unrealized Securities Available For Sale Gain (Loss) [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Securities gains, net	[3]	19	6	29
Income tax (expense) benefits	[3]	(7)	(2)	(10)
Net income (loss)	[3]	12	4	19
Accumulated Net Gain (Loss) from Derivative Instruments Designated as Cash Flow Hedges [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net interest income and other financing income	[3]	86	143	153
Income tax (expense) benefits	[3]	(33)	(54)	(58)
Net income (loss)	[3]	53	89	95
Accumulated Defined Benefit Pension Plans Adjustment [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Salaries and employee benefits	[3]	(48)	(34)	(48)
Income tax (expense) benefits	[3]	17	12	17
Net income (loss)	[3]	(31)	(22)	(31)
Accumulated Defined Benefit Plans Adjustment, Net Prior Service Cost (Credit) [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Salaries and employee benefits	[3],[4]	0	0	(1)
Accumulated Defined Benefit Plans Adjustment, Net Unamortized Gain (Loss) [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Salaries and employee benefits	[3],[4]	$ (48)	$ (34)	$ (47)
[1]	Income tax expense includes amortization of affordable housing investments of $160 million (including $23 million due to impact of Tax Reform), $117 million and $103 million for 2017, 2016 and 2015, respectively. Income tax expense for 2015 includes a benefit of $15 million related to an improved methodology implemented to estimate the effective state tax rate.
[2]	The table above does not include total income tax expense (benefit) from discontinued operations of $2 million, $3 million, and $(9) million in 2017, 2016 and 2015, respectively. The deferred income tax expense reflected in discontinued operations was $1 million, $18 million and $46 million in 2017, 2016 and 2015, respectively.
[3]	Amounts in parentheses indicate reductions to net income.
[4]	These accumulated other comprehensive income (loss) components are included in the computation of net periodic pension cost and are included in salaries and employee benefits on the consolidated statements of income (see Note 18 for additional details).

Stockholders' Equity And Acc105

Stockholders' Equity And Accumulated Other Comprehensive Income (Loss) (Narrative) (Details) - USD ($) $ / shares in Units, shares in Millions	Feb. 21, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Sep. 15, 2024	Dec. 15, 2017	Jun. 28, 2017
Stockholders' Equity And Comprehensive Income (Loss) [Line Items]
Dividends, Preferred Stock		$ 64,000,000	$ 64,000,000	$ 64,000,000
Cash dividend declared (in dollars per share)		$ 0.315	$ 0.255	$ 0.23
Stock Repurchase Program, Authorized Amount							$ 1,470,000,000
Shares repurchased (in shares)		65.7
ValueofTotalCommonStockRepurchasedUnderCurrentRepurchaseProgram		$ 1,000,000,000
Payments for Repurchase of Common Stock		1,275,000,000	$ 839,000,000	$ 623,000,000
Subsequent Event [Member]
Stockholders' Equity And Comprehensive Income (Loss) [Line Items]
Shares repurchased (in shares)	12.5
Payments for Repurchase of Common Stock	$ 235,000,000
Series A Preferred Stock [Member]
Stockholders' Equity And Comprehensive Income (Loss) [Line Items]
Dividends, Preferred Stock		$ 32,000,000	32,000,000
ExcessofRedemptionAmountOverCarryingAmount						$ 113,000,000
PreferredDividendsReductiontoRetainedEarningsatRedemption						100,000,000
PreferredStockIssuanceCostsReductiontoNetIncome						$ 13,000,000
Series A Preferred Stock [Member] | Debt Instrument, Redemption, Period One [Member]
Stockholders' Equity And Comprehensive Income (Loss) [Line Items]
Preferred Stock, Redemption Terms		90 days
Series B Preferred Stock [Member]
Stockholders' Equity And Comprehensive Income (Loss) [Line Items]
Dividends, Preferred Stock		$ 32,000,000	$ 32,000,000
Series B Preferred Stock [Member] | Subsequent Event [Member]
Stockholders' Equity And Comprehensive Income (Loss) [Line Items]
ExcessofRedemptionAmountOverCarryingAmount					$ 67,000,000
PreferredDividendsReductiontoRetainedEarningsatRedemption					52,000,000
PreferredStockIssuanceCostsReductiontoNetIncome					$ 15,000,000
Preferred Stock [Member]
Stockholders' Equity And Comprehensive Income (Loss) [Line Items]
Preferred stock, liquidation preference of per share (in dollars per share)		$ 1,000
Preferred Stock [Member] | Depositary Shares [Member]
Stockholders' Equity And Comprehensive Income (Loss) [Line Items]
Preferred stock, liquidation preference of per share (in dollars per share)		$ 25

Earnings (Loss) Per Common S106

Earnings (Loss) Per Common Share (Computation Of Basic And Diluted Earnings (Loss) Per Common Share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Numerator:
Income from continuing operations		$ 1,257	$ 1,158	$ 1,075
Preferred stock dividends		(64)	(64)	(64)
Income from continuing operations available to common shareholders		1,193	1,094	1,011
Income (loss) from discontinued operations, net of tax		6	5	(13)
Net income available to common shareholders		$ 1,199	$ 1,099	$ 998
Denominator:
Weighted-average common shares outstanding—basic		1,186	1,255	1,325
Potential common shares		12	6	9
Weighted-average common shares outstanding—diluted		1,198	1,261	1,334
Earnings per common share from continuing operations:
Basic	[1]	$ 1.01	$ 0.87	$ 0.76
Diluted	[1]	1	0.87	0.76
Earnings (loss) per common share from discontinued operations:
Basic	[1]	0.01	0	(0.01)
Diluted	[1]	0	0	(0.01)
Earnings per common share:
Basic	[1]	1.01	0.87	0.75
Diluted	[1]	$ 1	$ 0.87	$ 0.75
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		14	27	29
[1]	Certain per share amounts may not appear to reconcile due to rounding.

Share-Based Payments (Summary O

Share-Based Payments (Summary Of Compensation Costs Recognized In The Consolidated Statements of Operations) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Tax benefits related to compensation cost	[1]	$ (23)	$ (20)	$ (19)
Allocated Share-based Compensation Expense, Net of Tax		39	32	31
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation		(10)
Deferred Tax Expense from Stock Options Exercised		5
Restricted Stock Awards [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-Based Compensation Expense		$ 62	$ 52	$ 50
[1]	The tax benefits related to share-based compensation cost for 2017 exclude (a) excess tax benefits of $10 million related to settled share-based compensation awards and (b) tax expense of $5 million related to expired stock options.

Share-Based Payments (Summar108

Share-Based Payments (Summary Of Activity Related To Stock Options) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Options, Outstanding at beginning of period	13,455,047	19,350,157	25,316,676
Number of Options, Granted	0	0	0
Number of Options, Exercised	(1,204,138)	(1,954,064)	(546,455)
Number of Options, Forfeited or Expired	(2,843,011)	(3,941,046)	(5,420,064)
Number of Options, Outstanding at end of period	9,407,898	13,455,047	19,350,157	25,316,676
Number of Options, Exercisable at end of period	9,407,898
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Weighted-Average Exercise Price, Outstanding at beginning of period	$ 19.37	$ 21.06	$ 23.07
Weighted-Average Exercise Price, Granted	0	0	0
Weighted-Average Exercise Price, Exercised	6.69	5.80	6.93
Weighted-Average Exercise Price, Forfeited or Expired	34	34.39	31.88
Weighted-Average Exercise Price, Outstanding at end of period	16.58	$ 19.37	$ 21.06	$ 23.07
Weighted-Average Exercise Price, Exercisable at end of period	$ 16.58
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Aggregate Intrinsic Value, at end of period	$ 35	$ 34	$ 20	$ 28
Aggregate intrinsic Value, Exercisable at end of period	$ 35
Weighted-Average Contractual Term (in years), Outstanding	1 year 17 days	1 year 9 months 29 days	2 years 5 months 5 days	2 years 9 months 29 days
Weighted-Average Contractual Term (in years), Exercisable	1 year 17 days

Share-Based Payments (Summar109

Share-Based Payments (Summary Of Restricted Stock Awards And Performance Stock Awards Activity) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of Shares, Non-vested at beginning of period	16,558,942,000,000	16,374,242,000,000	18,427,409,000,000
Number of Shares, Granted	3,993,591,000,000	6,867,672,000,000	6,670,905,000,000
Number of Shares, Vested	(4,657,544,000,000)	(5,829,974,000,000)	(8,222,576,000,000)
Number of Shares, Forfeited	(631,955,000,000)	(852,998,000,000)	(501,496,000,000)
Number of Shares, Non-vested at end of period	15,263,034,000,000	16,558,942,000,000	16,374,242,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted-Average Grant Date Fair Value, Non-vested at beginning of period	$ 9.31	$ 9.51	$ 8.07
Weighted-Average Grant Date Fair Value, Granted	14.57	7.93	9.22
Weighted-Average Grant Date Fair Value, Vested	11.06	8.28	6.09
Weighted-Average Grant Date Fair Value, Forfeited	10.04	9.07	8.81
Weighted-Average Grant Date Fair Value, Non-vested at end of period	$ 10.12	$ 9.31	$ 9.51

Share-Based Payments (Narrative

Share-Based Payments (Narrative) (Details) - USD ($) shares in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Apr. 23, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of incentive awards (in years)	3 years
Contractual lives of options granted under long-term incentive compensation plans	10 years
Number of Common Share Equivalents Authorized Under Long-term Incentive Plans				60
Number of Remaining Common Share Equivalents Available for Grant Under Long-term Incentive Plans	45
Aggregate intrinsic value of exercised options	$ 13,000,000	$ 17,000,000	$ 5,000,000
Cash received from options exercised	8,000,000	11,000,000	4,000,000
Pre Tax Amount Of Non Vested Stock Options And Restricted Stock Awards And Units Not Yet Recognized	$ 54,000,000
Non-vested awards, compensation cost not yet recognized, weighted-average period for recognition	1 year 8 months 20 days
Total fair value of shares vested during the period	$ 68,000,000	47,000,000	82,000,000
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount	$ 0	0	0
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance Based Restricted Stock Performance Period	3 years
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Service Share-based Compensation, Tax Benefit from Exercise of Stock Options	$ 3,000,000	$ 4,000,000	$ 1,000,000

Employee Benefit Plans (Schedul

Employee Benefit Plans (Schedule of Defined Benefit Plans Disclosures) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017		Dec. 31, 2016		Dec. 31, 2015
Change in Benefit Obligation [Roll Forward]
Projected Benefit Obligation, Beginning of Period	$ 2,159		$ 2,062
Service cost	38		39		$ 44
Interest cost	77		78		90
Actuarial Gains (Losses)	214		80
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(157)		(98)
Administration Expenses	(3)		(3)
Plan Settlements	(43)		0
Plan Amendments	0		1
Projected Benefit Obligation, End of Period	2,285		2,159		2,062
Change in Plan Assets [Roll Forward]
Fair Value of Plan Assets, beginning of period	1,990	[1]	1,930
Actual Return on Plan Assets	306		151
Company Contributions	125		10
Defined Benefit Plan, Plan Assets, Benefits Paid	(157)		(98)
Administration Expenses	(3)		(3)
Plan Settlements	(43)		0
Fair Value of Plan Assets, end of period	2,218	[1]	1,990	[1]	1,930
Funded Status and Accrued Benefit Cost at Measurement Date	(67)		(169)
Amount recognized in the Consolidated Balance Sheets:
Other assets (liabilities)	(67)		(169)
Pre-tax amounts recognized in Accumulated Other Comprehensive (Income) Loss:
Net actuarial loss (gain)	692		689
Prior service cost (credit)	1		1
Total amounts recognized in Accumulated Other Comprehensive Income (Loss)	693		690
Qualified Plan [Member] | Pension Plan [Member]
Change in Benefit Obligation [Roll Forward]
Projected Benefit Obligation, Beginning of Period	1,979		1,895
Service cost	34		35		40
Interest cost	72		73		84
Actuarial Gains (Losses)	202		67
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(150)		(88)
Administration Expenses	(3)		(3)
Plan Settlements	0		0
Plan Amendments	0		0
Projected Benefit Obligation, End of Period	2,134		1,979		1,895
Change in Plan Assets [Roll Forward]
Fair Value of Plan Assets, beginning of period	1,990		1,930
Actual Return on Plan Assets	306		151
Company Contributions	75		0
Defined Benefit Plan, Plan Assets, Benefits Paid	(150)		(88)
Administration Expenses	(3)		(3)
Plan Settlements	0		0
Fair Value of Plan Assets, end of period	2,218		1,990		1,930
Funded Status and Accrued Benefit Cost at Measurement Date	84		11
Amount recognized in the Consolidated Balance Sheets:
Other assets (liabilities)	84		11
Pre-tax amounts recognized in Accumulated Other Comprehensive (Income) Loss:
Net actuarial loss (gain)	644		637
Prior service cost (credit)	0		0
Total amounts recognized in Accumulated Other Comprehensive Income (Loss)	644		637
Nonqualified Plan [Member] | Supplemental Employee Retirement Plan [Member]
Change in Benefit Obligation [Roll Forward]
Projected Benefit Obligation, Beginning of Period	180		167
Service cost	4		4		4
Interest cost	5		5		6
Actuarial Gains (Losses)	12		13
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(7)		(10)
Administration Expenses	0		0
Plan Settlements	(43)		0
Plan Amendments	0		1
Projected Benefit Obligation, End of Period	151		180		167
Change in Plan Assets [Roll Forward]
Fair Value of Plan Assets, beginning of period	0		0
Actual Return on Plan Assets	0		0
Company Contributions	50		10
Defined Benefit Plan, Plan Assets, Benefits Paid	(7)		(10)
Administration Expenses	0		0
Plan Settlements	(43)		0
Fair Value of Plan Assets, end of period	0		0		$ 0
Funded Status and Accrued Benefit Cost at Measurement Date	(151)		(180)
Amount recognized in the Consolidated Balance Sheets:
Other assets (liabilities)	(151)		(180)
Pre-tax amounts recognized in Accumulated Other Comprehensive (Income) Loss:
Net actuarial loss (gain)	48		52
Prior service cost (credit)	1		1
Total amounts recognized in Accumulated Other Comprehensive Income (Loss)	$ 49		$ 53
[1]	In accordance with accounting guidance adopted by Regions in 2016, investments that are measured at fair value using the net asset value per share (or its equivalent) practical expedient are no longer required to be classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of amounts reported in the fair value hierarchy to amounts reported on the balance sheet. See Note 1 for further discussion.

Employee Benefit Plans (Compone

Employee Benefit Plans (Components Of Net Periodic Pension Costs) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 38	$ 39	$ 44
Interest cost	77	78	90
Expected return on plan assets	(143)	(145)	(152)
Amortization of actuarial loss	36	34	47
Amortization of prior service cost	0	0	1
Settlement charge	12	0	2
Net periodic pension (benefit) cost	20	6	32
Qualified Plan [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	34	35	40
Interest cost	72	73	84
Expected return on plan assets	(143)	(145)	(152)
Amortization of actuarial loss	32	31	43
Amortization of prior service cost	0	0	0
Settlement charge	0	0	0
Net periodic pension (benefit) cost	(5)	(6)	15
Nonqualified Plan [Member] | Supplemental Employee Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	4	4	4
Interest cost	5	5	6
Expected return on plan assets	0	0	0
Amortization of actuarial loss	4	3	4
Amortization of prior service cost	0	0	1
Settlement charge	12	0	2
Net periodic pension (benefit) cost	$ 25	$ 12	$ 17

Employee Benefit Plans (Estimat

Employee Benefit Plans (Estimated Amounts That Will Be Amortized From Accumulated Other Comprehensive Income (Loss) Into Net Periodic Benefit Cost) (Details) $ in Millions	Dec. 31, 2017USD ($)
Nonqualified Plan [Member] | Supplemental Employee Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Future Amortization of Actuarial loss	$ 4
Amount to be Amortized from Accumulated Other Comprehensive Income (Loss) Next Fiscal Year	4
Qualified Plan [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Future Amortization of Actuarial loss	33
Amount to be Amortized from Accumulated Other Comprehensive Income (Loss) Next Fiscal Year	$ 33

Employee Benefit Plans (Sche114

Employee Benefit Plans (Schedule of Assumptions Used) (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Qualified Plan [Member] | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate for benefit obligation	3.71%	4.32%
Rate of annual compensation increase, benefit obligation	3.75%	3.75%
Discount rate for net periodic benefit cost	4.34%	4.56%	4.20%
Expected long-term rate of return on plan assets for net periodic benefit cost	7.25%	7.75%	7.75%
Rate of annual compensation increase, net periodic benefit cost	3.75%	3.75%	3.75%
Nonqualified Plan [Member] | Supplemental Employee Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate for benefit obligation	3.50%	3.93%
Rate of annual compensation increase, benefit obligation	3.75%	3.75%
Discount rate for net periodic benefit cost	3.93%	4.19%	3.75%
Rate of annual compensation increase, net periodic benefit cost	3.75%	3.75%	3.75%

Employee Benefit Plans (Present

Employee Benefit Plans (Presentation Of The Fair Value Of Regions' Qualified Defined-Benefit Pension Plans' Financial Assets) (Details) - USD ($) $ in Millions		Dec. 31, 2017		Dec. 31, 2016		Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		$ 2,218	[1]	$ 1,990	[1]	$ 1,930
Collective Investment Trust Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Alternative Investment, Fair Value Disclosure		869		746
Collective Investment Trust Funds [Member] | Fixed Income Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Alternative Investment, Fair Value Disclosure	[1]	388		320
Collective Investment Trust Funds [Member] | Common Stock Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Alternative Investment, Fair Value Disclosure	[1]	265		244
Collective Investment Trust Funds [Member] | International Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Alternative Investment, Fair Value Disclosure	[1]	216		182
Hedge Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Alternative Investment, Fair Value Disclosure	[1]	46		16
Real Estate Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Alternative Investment, Fair Value Disclosure	[1]	197		239
Private Equity Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Alternative Investment, Fair Value Disclosure	[1]	111		107
Estimate of Fair Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		995		882
Estimate of Fair Value [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		48		52
Estimate of Fair Value [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		388		314
Estimate of Fair Value [Member] | Fixed Income Securities [Member] | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		172		144
Estimate of Fair Value [Member] | Fixed Income Securities [Member] | Corporate Bond Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		216		170
Estimate of Fair Value [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		459		324
Estimate of Fair Value [Member] | Equity Securities [Member] | Domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		427		303
Estimate of Fair Value [Member] | Equity Securities [Member] | International [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		32		21
Estimate of Fair Value [Member] | Mutual Funds [Member] | International [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		100		192
Estimate of Fair Value [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		607		568
Estimate of Fair Value [Member] | Level 1 [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		48		52
Estimate of Fair Value [Member] | Level 1 [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0		0
Estimate of Fair Value [Member] | Level 1 [Member] | Fixed Income Securities [Member] | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0		0
Estimate of Fair Value [Member] | Level 1 [Member] | Fixed Income Securities [Member] | Corporate Bond Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0		0
Estimate of Fair Value [Member] | Level 1 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		459		324
Estimate of Fair Value [Member] | Level 1 [Member] | Equity Securities [Member] | Domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		427		303
Estimate of Fair Value [Member] | Level 1 [Member] | Equity Securities [Member] | International [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		32		21
Estimate of Fair Value [Member] | Level 1 [Member] | Mutual Funds [Member] | International [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		100		192
Estimate of Fair Value [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		388		314
Estimate of Fair Value [Member] | Level 2 [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0		0
Estimate of Fair Value [Member] | Level 2 [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		388		314
Estimate of Fair Value [Member] | Level 2 [Member] | Fixed Income Securities [Member] | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		172		144
Estimate of Fair Value [Member] | Level 2 [Member] | Fixed Income Securities [Member] | Corporate Bond Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		216		170
Estimate of Fair Value [Member] | Level 2 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0		0
Estimate of Fair Value [Member] | Level 2 [Member] | Equity Securities [Member] | Domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0		0
Estimate of Fair Value [Member] | Level 2 [Member] | Equity Securities [Member] | International [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0		0
Estimate of Fair Value [Member] | Level 2 [Member] | Mutual Funds [Member] | International [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0		0
Estimate of Fair Value [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0		0
Estimate of Fair Value [Member] | Level 3 [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0		0
Estimate of Fair Value [Member] | Level 3 [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0		0
Estimate of Fair Value [Member] | Level 3 [Member] | Fixed Income Securities [Member] | US Treasury and Government [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0		0
Estimate of Fair Value [Member] | Level 3 [Member] | Fixed Income Securities [Member] | Corporate Bond Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0		0
Estimate of Fair Value [Member] | Level 3 [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0		0
Estimate of Fair Value [Member] | Level 3 [Member] | Equity Securities [Member] | Domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0		0
Estimate of Fair Value [Member] | Level 3 [Member] | Equity Securities [Member] | International [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		0		0
Estimate of Fair Value [Member] | Level 3 [Member] | Mutual Funds [Member] | International [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets		$ 0		$ 0
[1]	In accordance with accounting guidance adopted by Regions in 2016, investments that are measured at fair value using the net asset value per share (or its equivalent) practical expedient are no longer required to be classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of amounts reported in the fair value hierarchy to amounts reported on the balance sheet. See Note 1 for further discussion.

Employee Benefit Plans (Informa

Employee Benefit Plans (Information About The Expected Cash Flows For The Qualified and Non-Qualified Pension Plans) (Details) $ in Millions	Dec. 31, 2017USD ($)
Qualified Plan [Member] | Pension Plan [Member]
Defined Benefit Plan, Expected Future Employer Contributions [Abstract]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	$ 0
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	93
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	95
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	98
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	102
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	105
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	573
Nonqualified Plan [Member] | Supplemental Employee Retirement Plan [Member]
Defined Benefit Plan, Expected Future Employer Contributions [Abstract]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	10
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	10
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	11
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	11
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	22
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	16
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	$ 56

Employee Benefit Plans (Narrati

Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Expected long-term rate of return on plan assets for net periodic benefit cost, next fiscal year	6.82%
Minimum Years Of Service For Eligible Employees Of Postretirement Plans	1 year
Minimum Number Of Hours Worked By Employees	1,000
Automatic Cash Contribution	2.00%	2.00%	2.00%
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 18	$ 17	$ 15
Defined Contribution Plan, Employer Matching Contribution, Percent	4.00%
Defined Contribution Plan, Cost	$ 48	$ 45	40
Total Company Common Stock Shares Held Under Defined Contribution Plan	26,000,000	29,000,000
Dividends Earned By Defined Contribution Plan	$ 8	$ 9	$ 8
Defined Benefit Plan Current Health Care Cost Trend Rate	6.40%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	4.50%
Defined Benefit Plan, Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate	2,027
Supplemental Employee Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Benefit Obligation	$ 143	166
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Benefit Obligation	$ 2,000	1,800
Number of shares held in plan assets relating to company's common stock (whole number)	2,855,618
Market Value Of Companys Common Stock Held In Plan Assets	$ 49
Approximate percentage of company's common stock shares held in plan assets	2.20%
Defined Benefit Postretirement Health Coverage [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Benefit Obligation	$ 19	$ 20
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation For Defined Benefit Plan Equity Securities	51.00%
Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation For Defined Benefit Plan Equity Securities	37.00%
Other Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation For Defined Benefit Plan Equity Securities	12.00%

Other Non-Interest Income an118

Other Non-Interest Income and Expense (Other Non-Interest Income) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Other Income and Expenses [Abstract]
Capital Markets Fee Income and Other	$ 161	$ 152	$ 104
Insurance Commissions and Fees	145	148	140
Bank Owned Life Insurance Income	81	95	74
Commercial Credit Fee Income	71	73	76
Investment Services Fees Income	60	58	55
Insurance Proceeds	0	50	91
Market value adjustment on employee benefit plans	16	3	(3)
Other Miscellaneous Income	70	116	115
Other Non-Interest Income	$ 604	$ 695	$ 652

Other Non-Interest Income an119

Other Non-Interest Income and Expense (Other Non-Interest Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Other Income and Expenses [Abstract]
Outside Services	$ 172	$ 154	$ 149
FDIC insurance assessments	108	99	105
Professional, legal and regulatory expenses	95	89	137
Marketing	93	101	98
Credit / Checkcard Expenses	50	55	54
Branch Consolidation And Property and Equipment Charges	22	58	56
Visa class B shares expense	19	15	9
Provision For Unfunded Credit Commitments	(16)	17	(13)
(Gain) loss on early extinguishment of debt	0	14	43
Other Miscellaneous Expenses	452	437	422
Other Noninterest Expense	$ 995	$ 1,039	$ 1,060

Income Taxes (Components Of Inc

Income Taxes (Components Of Income Tax (Benefit) Expense) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
Current Federal Tax Expense (Benefit)	[1]	$ 376	$ 444	$ 293
Current State and Local Tax Expense (Benefit)	[1]	30	21	7
Current Income Tax Expense (Benefit)	[1]	406	465	300
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
Deferred Federal Income Tax Expense (Benefit)	[1]	172	2	115
Deferred State and Local Income Tax Expense (Benefit)	[1]	36	47	40
Deferred income tax expense (benefit)	[1]	208	49	155
Income tax expense (benefit)	[1],[2]	$ 614	$ 514	$ 455
[1]	The table above does not include total income tax expense (benefit) from discontinued operations of $2 million, $3 million, and $(9) million in 2017, 2016 and 2015, respectively. The deferred income tax expense reflected in discontinued operations was $1 million, $18 million and $46 million in 2017, 2016 and 2015, respectively.
[2]	Income tax expense includes amortization of affordable housing investments of $160 million (including $23 million due to impact of Tax Reform), $117 million and $103 million for 2017, 2016 and 2015, respectively. Income tax expense for 2015 includes a benefit of $15 million related to an improved methodology implemented to estimate the effective state tax rate.

Income Taxes (Income Tax Rate R

Income Taxes (Income Tax Rate Reconciliation) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Abstract]
Income Tax Reconciliation, Income Tax Expense (Benefit), at Federal Statutory Income Tax Rate	[1]	$ 655	$ 585	$ 535
Income tax expense	[1],[2]	$ 614	$ 514	$ 455
Effective Income Tax Rate, Continuing Operations	[1]	32.80%	30.70%	29.70%
Increase (decrease) in taxes resulting from: [Abstract]
Income Tax Reconciliation, State and Local Income Taxes	[1]	$ 43	$ 44	$ 30
Effective Income Tax Rate Reconciliation, Tax Exempt Income, Amount	[1]	(54)	(49)	(44)
Income Tax Reconciliation, Tax Credits	[1]	(52)	(50)	(47)
Additional Income Tax Expense Recognized due to Tax Reform	[1]	52	0	0
Effective Income Tax Rate Reconciliation, Bank-Owned Life Insurance, Amount	[1]	(32)	(37)	(30)
Income Tax Reconciliation, Nondeductible Expense, Leases	[1]	16	28	18
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount	[1]	$ (14)	$ (7)	$ (7)
[1]	Income tax expense includes amortization of affordable housing investments of $160 million (including $23 million due to impact of Tax Reform), $117 million and $103 million for 2017, 2016 and 2015, respectively. Income tax expense for 2015 includes a benefit of $15 million related to an improved methodology implemented to estimate the effective state tax rate.
[2]	The table above does not include total income tax expense (benefit) from discontinued operations of $2 million, $3 million, and $(9) million in 2017, 2016 and 2015, respectively. The deferred income tax expense reflected in discontinued operations was $1 million, $18 million and $46 million in 2017, 2016 and 2015, respectively.

Income Taxes (Summary Of Signif

Income Taxes (Summary Of Significant Components Of Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Deferred Tax Assets [Abstract]
Deferred Tax Assets, Other Comprehensive Income	$ 253	$ 338
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Provision for Loan Losses	249	447
Deferred Tax Assets, Operating Loss Carryforwards, State and Local	82	88
Deferred Tax Assets Accrued Expenses	55	92
Federal Tax Credit Carryforwards Before Allowance	13	13
Deferred Tax Assets, Property, Plant and Equipment	4	0
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Benefits	0	37
Deferred Tax Assets, Other	33	59
Deferred Tax Assets, Gross	689	1,074
Deferred Tax Assets, Valuation Allowance	(34)	(30)
Deferred Tax Assets, Net of Valuation Allowance	655	1,044
Deferred Tax Liabilities [Abstract]
Deferred Tax Liabilities, Leasing Arrangements	292	424
Deferred Tax Liabilities, Goodwill and Intangible Assets	99	156
Deferred Tax Liabilities, Mortgage Servicing Rights	63	93
Deferred Tax Liabilities, Property, Plant and Equipment	0	15
Deferred Tax Liabilities, Other	38	48
Deferred Tax Liabilities, Gross	492	736
Deferred Tax Assets, Net	$ 163	$ 308

Income Taxes (Summary Of Detail

Income Taxes (Summary Of Detail Of Tax Carryforwards) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016
Income Tax Contingency [Line Items]
Operating Loss Carryforwards, Valuation Allowance		$ (34)	$ (30)
Deferred Tax Assets, Net		163	308
Deferred Tax Assets, Operating Loss Carryforwards, State and Local		82	$ 88
Alternate Minimum Tax Credits Federal [Member]
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Deferred Tax Asset	[1]	13
Tax Credit Carryforward, Valuation Allowance	[1]	0
Deferred Tax Assets, Net	[1]	13
Net Operating Losses States Date Range One [Member]
Income Tax Contingency [Line Items]
Operating Loss Carryforwards, Valuation Allowance		(9)
Deferred Tax Assets, Net		33
Deferred Tax Assets, Operating Loss Carryforwards, State and Local		42
Pre Tax Earnings Necessary To Realize	[2]	553
Net Operating Losses States Date Range Two [Member]
Income Tax Contingency [Line Items]
Operating Loss Carryforwards, Valuation Allowance		(21)
Deferred Tax Assets, Net		12
Deferred Tax Assets, Operating Loss Carryforwards, State and Local		33
Pre Tax Earnings Necessary To Realize	[2]	240
Net Operating Losses States Date Range Three [Member]
Income Tax Contingency [Line Items]
Operating Loss Carryforwards, Valuation Allowance		(4)
Deferred Tax Assets, Net		3
Deferred Tax Assets, Operating Loss Carryforwards, State and Local		7
Pre Tax Earnings Necessary To Realize	[2]	44
Other Credits States Date Range One [Member]
Income Tax Contingency [Line Items]
Deferred Tax Asset Balance		0
Tax Credit Carryforward, Valuation Allowance		0
Deferred Tax Assets, Net		0
Other Credits States Date Range Two [Member]
Income Tax Contingency [Line Items]
Deferred Tax Asset Balance		1
Tax Credit Carryforward, Valuation Allowance		0
Deferred Tax Assets, Net		$ 1
Minimum [Member] | Net Operating Losses States Date Range One [Member]
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Expiration Date		Dec. 31, 2018
Minimum [Member] | Net Operating Losses States Date Range Two [Member]
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Expiration Date		Dec. 31, 2023
Minimum [Member] | Net Operating Losses States Date Range Three [Member]
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Expiration Date		Dec. 31, 2030
Minimum [Member] | Other Credits States Date Range One [Member]
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Expiration Date		Dec. 31, 2018
Minimum [Member] | Other Credits States Date Range Two [Member]
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Expiration Date		Dec. 31, 2023
Maximum [Member] | Net Operating Losses States Date Range One [Member]
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Expiration Date		Dec. 31, 2022
Maximum [Member] | Net Operating Losses States Date Range Two [Member]
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Expiration Date		Dec. 31, 2029
Maximum [Member] | Net Operating Losses States Date Range Three [Member]
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Expiration Date		Dec. 31, 2037
Maximum [Member] | Other Credits States Date Range One [Member]
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Expiration Date		Dec. 31, 2022
Maximum [Member] | Other Credits States Date Range Two [Member]
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Expiration Date		Dec. 31, 2029
[1]	Tax Reform repealed the AMT for tax years beginning after December 31, 2017 and provides a mechanism to utilize any AMT credit carryover through 2020 with any remaining credits being fully refundable in 2021.
[2]	N/A indicates that credits are not measured on a pre-tax basis.

Income Taxes (Reconciliation Of

Income Taxes (Reconciliation Of Beginning And Ending Amount Of Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of year	$ 31	$ 38	$ 50
Unrecognized Tax Benefits, Increases Resulting from Current Period Tax Positions	0	3	2
Unrecognized Tax Benefits, Decreases Resulting from Prior Period Tax Positions	0	(6)	(8)
Unrecognized Tax Benefits, Decreases Resulting from Settlements with Taxing Authorities	0	(3)	(6)
Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations	(4)	(1)	0
Balance at end of year	$ 27	$ 31	$ 38

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Abstract]
Tax Adjustments, Settlements, and Unusual Provisions		$ 160	$ 117	$ 103
Discontinued Operations Income tax expense (benefit)		2	3	(9)
Deferred Tax Effect Of Discontinued Operation		$ 1	$ 18	$ 46
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate		35.00%	35.00%	35.00%
Other Tax Expense (Benefit)				$ 15
Deferred Tax Assets, Net		$ 163	$ 308
Net Operating Losses And Tax Carryforwards		62
Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration		46
Deferred Tax Assets, Operating Loss Carryforwards, Not Subject to Expiration		101
Taxable Temporary Differences That Will Offset Amount Of Gross Deferred Tax Asset		430
Operating Loss Carryforwards, Valuation Allowance		34	30
Decrease in Unrecognized Tax Benefits is Reasonably Possible		24
Unrecognized Tax Benefits that Would Impact Effective Tax Rate		21	20	24
Income Tax Examination, Penalties and Interest Expense		(2)	1	(1)
Income Tax Examination, Penalties and Interest Accrued		2	4
Valuation Allowances and Reserves, Period Increase (Decrease)		6
Investment Tax Credit		$ 102	54	0
Federal Statutory Income Tax Rate, Next Fiscal Year, Percent		21.00%
Additional Income Tax Expense Recognized due to Tax Reform	[1]	$ 52	$ 0	$ 0
Additional Income Tax Expense Recognized Related to Revaluation of Net Deferred Tax Asset Due to Tax Reform		25
Additional Income Tax Expense Recognized related to Revision of Proportional Amortization Calculation associated with Low Income Housing Investments due to Tax Reform		23
Additional Income Tax Expense Recognized related to Revaluation of the Reserve for UTBs due to Tax Reform		4
Reclassification of the Tax Reform related revaluation of deferred tax items within accumulated other comprehensive income		$ 133
[1]	Income tax expense includes amortization of affordable housing investments of $160 million (including $23 million due to impact of Tax Reform), $117 million and $103 million for 2017, 2016 and 2015, respectively. Income tax expense for 2015 includes a benefit of $15 million related to an improved methodology implemented to estimate the effective state tax rate.

Derivative Financial Instrum126

Derivative Financial Instruments And Hedging Activities (Schedule Of Derivative Instruments Notional And Fair Values) (Details) - USD ($) $ in Millions		Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount		$ 81,449	$ 81,403
Estimated Fair Value, Gain		394	579
Estimated Fair Value, Loss		641	887
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount		9,885	11,257
Estimated Fair Value, Gain	[1]	6	26
Estimated Fair Value, Loss	[1]	231	309
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount		71,564	70,146
Estimated Fair Value, Gain	[1]	388	553
Estimated Fair Value, Loss	[1]	410	578
Interest Rate Swaps [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount		40,841	41,851
Interest Rate Swaps [Member] | Not Designated as Hedging Instrument [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Estimated Fair Value, Gain	[1]	308	412
Interest Rate Swaps [Member] | Not Designated as Hedging Instrument [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Estimated Fair Value, Loss	[1]	342	467
Interest Rate Options [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount		4,598	3,877
Interest Rate Options [Member] | Not Designated as Hedging Instrument [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Estimated Fair Value, Gain	[1]	23	24
Interest Rate Options [Member] | Not Designated as Hedging Instrument [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Estimated Fair Value, Loss	[1]	15	12
Interest Rate Futures And Forward Commitments [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount		20,404	18,605
Interest Rate Futures And Forward Commitments [Member] | Not Designated as Hedging Instrument [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Estimated Fair Value, Gain	[1]	6	11
Interest Rate Futures And Forward Commitments [Member] | Not Designated as Hedging Instrument [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Estimated Fair Value, Loss	[1]	5	6
Other Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount		5,721	5,813
Other Contract [Member] | Not Designated as Hedging Instrument [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Estimated Fair Value, Gain	[1]	51	106
Other Contract [Member] | Not Designated as Hedging Instrument [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Estimated Fair Value, Loss	[1]	48	93
Fair Value Hedging [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount		3,060	2,257
Fair Value Hedging [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Estimated Fair Value, Gain	[1]	1	7
Fair Value Hedging [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Estimated Fair Value, Loss	[1]	43	40
Cash Flow Hedging [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount		6,825	9,000
Cash Flow Hedging [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Estimated Fair Value, Gain	[1]	5	19
Cash Flow Hedging [Member] | Interest Rate Swaps [Member] | Designated as Hedging Instrument [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Estimated Fair Value, Loss	[1]	$ 188	$ 269
[1]	Derivatives in a gain position are recorded as other assets and derivatives in a loss position are recorded as other liabilities on the consolidated balance sheets.

Derivative Financial Instrum127

Derivative Financial Instruments And Hedging Activities (Schedule Of The Effect Of Derivative Instruments On The Statements Of Operations) (Details) - Designated as Hedging Instrument [Member] - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in Income on Derivatives		$ (21)	$ (30)	$ (6)
Gain or (Loss) Recognized in Income on Related Hedged Item		19	27	11
Fair Value Hedging [Member] | Interest Rate Swaps [Member] | Debt/CDs [Member] | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in Income on Derivatives		2	12	17
Gain or (Loss) Recognized in Income on Related Hedged Item		(1)	(3)	4
Fair Value Hedging [Member] | Interest Rate Swaps [Member] | Debt/CDs [Member] | Other Non-Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in Income on Derivatives		(20)	(33)	(1)
Gain or (Loss) Recognized in Income on Related Hedged Item		22	32	1
Fair Value Hedging [Member] | Interest Rate Swaps [Member] | Available-for-Sale Securities [Member] | Other Non-Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in Income on Derivatives		1	0	(8)
Gain or (Loss) Recognized in Income on Related Hedged Item		(2)	(2)	6
Fair Value Hedging [Member] | Interest Rate Swaps [Member] | Available-for-Sale Securities [Member] | Interest Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in Income on Derivatives		(4)	(9)	(14)
Gain or (Loss) Recognized in Income on Related Hedged Item		0	0	0
Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in AOCI	[1],[2],[3]	(51)	(64)	42
Gain or (Loss) Reclassified from AOCI into Income	[1],[2],[3]	86	143	153
Cash Flow Hedging [Member] | Interest Rate Swaps [Member] | Interest Income On Loans [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain or (Loss) Recognized in AOCI	[1],[2],[3]	(51)	(64)	42
Gain or (Loss) Reclassified from AOCI into Income	[1],[2],[3]	$ 86	$ 143	$ 153
[1]	After-tax
[2]	All cash flow hedges were highly effective for all periods presented, and the change in fair value attributed to hedge ineffectiveness was not material.
[3]	Pre-tax

Derivative Financial Instrum128

Derivative Financial Instruments And Hedging Activities (Schedule Of Gains (Losses) Recognized Related To Derivatives Not Designated As Hedging Instruments) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivative [Line Items]
Gain or (Loss) of Derivatives Not Designated as Hedging Instruments		$ 31	$ 41	$ 57
Capital Markets Fee Income [Member]
Derivative [Line Items]
Gain or (Loss) of Derivatives Not Designated as Hedging Instruments	[1]	39	37	42
Capital Markets Fee Income [Member] | Interest Rate Swaps [Member]
Derivative [Line Items]
Gain or (Loss) of Derivatives Not Designated as Hedging Instruments	[1]	11	13	14
Capital Markets Fee Income [Member] | Interest Rate Options [Member]
Derivative [Line Items]
Gain or (Loss) of Derivatives Not Designated as Hedging Instruments	[1]	28	23	14
Capital Markets Fee Income [Member] | Interest Rate Futures And Forward Commitments [Member]
Derivative [Line Items]
Gain or (Loss) of Derivatives Not Designated as Hedging Instruments	[1]	10	4	3
Capital Markets Fee Income [Member] | Other Contract [Member]
Derivative [Line Items]
Gain or (Loss) of Derivatives Not Designated as Hedging Instruments	[1]	(10)	(3)	11
Mortgage Income [Member]
Derivative [Line Items]
Gain or (Loss) of Derivatives Not Designated as Hedging Instruments		(8)	4	15
Mortgage Income [Member] | Interest Rate Swaps [Member]
Derivative [Line Items]
Gain or (Loss) of Derivatives Not Designated as Hedging Instruments		2	(2)	13
Mortgage Income [Member] | Interest Rate Options [Member]
Derivative [Line Items]
Gain or (Loss) of Derivatives Not Designated as Hedging Instruments		(7)	(2)	(1)
Mortgage Income [Member] | Interest Rate Futures And Forward Commitments [Member]
Derivative [Line Items]
Gain or (Loss) of Derivatives Not Designated as Hedging Instruments		$ (3)	$ 8	$ 3
[1]	Capital markets fee income and other is included in Other income on the consolidated statements of income.

Derivative Financial Instrum129

Derivative Financial Instruments and Hedging Activities (Offsetting Derivatives) (Details) - USD ($) $ in Millions		Dec. 31, 2017	Dec. 31, 2016
Offsetting Derivative Assets [Abstract]
Offsetting Derivative Assets, Gross amounts recognized		$ 394	$ 579
Offsetting Derivative Assets, Gross amounts offset in the consolidated balance sheets	[1]	141	241
Offsetting Derivative Assets, Net amounts presented in the consolidated balance sheets		253	338
Offsetting Derivative Assets, Gross amounts not offset in the consolidated balance sheets
Financial instruments		2	4
Cash collateral received/posted		0	0
Net amounts		251	334
Offsetting Derivative Liabilities [Abstract]
Offsetting Derivative Liabilities, Gross Amount Recognized		641	887
Offsetting Derivative Liabilities, Gross amounts offset in the consolidated balance sheets	[1]	238	541
Offsetting Derivative Liabilities, Net amounts presented in the consolidated balance sheets		403	346
Offsetting Derivative Liabilities, Gross amounts not offset in the consolidated balance sheets
Financial instruments		50	50
Cash collateral received/posted		257	227
Net amounts		96	69
Cash collateral received, offset		34	48
Cash collateral posted		131	349
Subject to offsetting [Member]
Offsetting Derivative Assets [Abstract]
Offsetting Derivative Assets, Gross amounts recognized		231	414
Offsetting Derivative Liabilities [Abstract]
Offsetting Derivative Liabilities, Gross Amount Recognized		342	583
Not subject to offsetting [Member]
Offsetting Derivative Assets [Abstract]
Offsetting Derivative Assets, Gross amounts recognized		163	165
Offsetting Derivative Assets, Net amounts presented in the consolidated balance sheets		158
Offsetting Derivative Assets, Gross amounts not offset in the consolidated balance sheets
Cash collateral received/posted		140
Offsetting Derivative Liabilities [Abstract]
Offsetting Derivative Liabilities, Gross Amount Recognized		299	$ 304
Offsetting Derivative Liabilities, Net amounts presented in the consolidated balance sheets		$ 298
[1]	At December 31, 2017, gross amounts of derivative assets and liabilities offset in the consolidated balance sheets presented above include cash collateral received of $34 million and cash collateral posted of $131 million. At December 31, 2016, the gross amounts of derivative assets and liabilities offset in the consolidated balance sheets presented above include cash collateral received of $48 million and cash collateral posted of $349 million.

Derivative Financial Instrum130

Derivative Financial Instruments And Hedging Activities (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Terminated Cash Flow Hedge Unrealized Gain (Loss) To Be Reclassified From OCI, After Tax Amount	$ 147	$ 166
Pre Tax Income (Loss) Related to Amortization of Cash Flow Hedges	68	68
Cash flow hedge gain expected to be reclassified from other comprehensive income into earnings within the next 12 months	30
Pre-tax net income related to amortization of discontinued cash flow hedges	$ 53
Maximum Length of Time Hedged in Cash Flow Hedge	8 years
Derivative, Notional Amount	$ 81,449	81,403
Credit risk, defined as all positive exposures not collateralized	251	334
Maximum potential future exposure on swap participations	356
Aggregate fair value of all derivative instruments with credit risk	91	141
Posted collateral related to derivative instruments with credit risk	90	141
Not Designated as Hedging Instrument [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount	71,564	70,146
Interest Rate Lock Commitments [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount	197	274
Forward Sale Commitments [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount	481	786
Forward Rate Commitments and Futures Contracts [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Notional Amount	$ 4,800	$ 7,200

Fair Value Measurements (Schedu

Fair Value Measurements (Schedule Of Assets And Liabilities At Fair Value Measured On A Recurring Basis And Non-Recurring Basis) (Details) - USD ($) $ in Millions		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading account securities		$ 189	$ 124
Securities available for sale		23,628	23,781
Residential mortgage servicing rights at fair value		336	324	$ 252	$ 257
Derivative Assets		253	338
Derivative Liabilities		403	346
Loans held for sale, at fair value		325	447
Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading account securities		189	124
Securities available for sale		23,628	23,781
Mortgages Held-for-sale, Fair Value Disclosure		325	447
Residential mortgage servicing rights at fair value		336	324
Derivative Assets		394	579
Derivative Liabilities		641	887
Nonrecurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale, at fair value		20	7
Fair Value Foreclosed Property And Other Real Estate And Equipment Nonrecurring Basis		33	35
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading account securities		189	124
Securities available for sale		556	504
Derivative Assets		2	2
Derivative Liabilities		2	1
Loans held for sale, at fair value		0	0
Level 1 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading account securities		189	124
Securities available for sale		556	504
Mortgages Held-for-sale, Fair Value Disclosure		0	0
Residential mortgage servicing rights at fair value		0	0
Derivative Assets		2	2
Derivative Liabilities		2	1
Level 1 [Member] | Nonrecurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale, at fair value		0	0
Fair Value Foreclosed Property And Other Real Estate And Equipment Nonrecurring Basis		0	0
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading account securities		0	0
Securities available for sale		23,066	23,270
Derivative Assets		387	566
Derivative Liabilities		639	886
Loans held for sale, at fair value		328	689
Level 2 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading account securities		0	0
Securities available for sale		23,066	23,270
Mortgages Held-for-sale, Fair Value Disclosure		325	414
Residential mortgage servicing rights at fair value		0	0
Derivative Assets		387	566
Derivative Liabilities		639	886
Level 2 [Member] | Nonrecurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale, at fair value		0	0
Fair Value Foreclosed Property And Other Real Estate And Equipment Nonrecurring Basis		24	29
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading account securities		0	0
Securities available for sale		6	7
Derivative Assets		5	11
Derivative Liabilities		0	0
Loans held for sale, at fair value		20	33
Level 3 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading account securities	[1]	0	0
Securities available for sale	[1]	6	7
Mortgages Held-for-sale, Fair Value Disclosure	[1]	0	33
Residential mortgage servicing rights at fair value	[1]	336	324
Derivative Assets	[1]	5	11
Derivative Liabilities	[1]	0	0
Level 3 [Member] | Nonrecurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale, at fair value	[1]	20	7
Fair Value Foreclosed Property And Other Real Estate And Equipment Nonrecurring Basis	[1]	9	6
Interest Rate Swaps [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets		314	438
Derivative Liabilities		573	776
Interest Rate Swaps [Member] | Level 1 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets		0	0
Derivative Liabilities		0	0
Interest Rate Swaps [Member] | Level 2 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets		314	438
Derivative Liabilities		573	776
Interest Rate Swaps [Member] | Level 3 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets	[1]	0	0
Derivative Liabilities	[1]	0	0
Interest Rate Options [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets		23	24
Derivative Liabilities		15	12
Interest Rate Options [Member] | Level 1 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets		0	0
Derivative Liabilities		0	0
Interest Rate Options [Member] | Level 2 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets		18	13
Derivative Liabilities		15	12
Interest Rate Options [Member] | Level 3 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets	[1]	5	11
Derivative Liabilities	[1]	0	0
Interest Rate Futures And Forward Commitments [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets		6	11
Derivative Liabilities		5	6
Interest Rate Futures And Forward Commitments [Member] | Level 1 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets		0	0
Derivative Liabilities		0	0
Interest Rate Futures And Forward Commitments [Member] | Level 2 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets		6	11
Derivative Liabilities		5	6
Interest Rate Futures And Forward Commitments [Member] | Level 3 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets	[1]	0	0
Derivative Liabilities	[1]	0	0
Other Contract [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets		51	106
Derivative Liabilities		48	93
Other Contract [Member] | Level 1 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets		2	2
Derivative Liabilities		2	1
Other Contract [Member] | Level 2 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets		49	104
Derivative Liabilities		46	92
Other Contract [Member] | Level 3 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets	[1]	0	0
Derivative Liabilities	[1]	0	0
US Treasury Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		331	303
US Treasury Securities [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		331	303
US Treasury Securities [Member] | Level 1 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		331	303
US Treasury Securities [Member] | Level 2 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		0	0
US Treasury Securities [Member] | Level 3 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	[1]	0	0
Federal Agency Securities [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		28	35
Federal Agency Securities [Member] | Level 1 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		0	0
Federal Agency Securities [Member] | Level 2 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		28	35
Federal Agency Securities [Member] | Level 3 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	[1]	0	0
Obligations of States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale			1
Obligations of States and Political Subdivisions [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		0	1
Obligations of States and Political Subdivisions [Member] | Level 1 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		0	0
Obligations of States and Political Subdivisions [Member] | Level 2 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		0	1
Obligations of States and Political Subdivisions [Member] | Level 3 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	[1]	0	0
Residential Agency [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		17,431	17,371
Residential Agency [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		17,431	17,371
Residential Agency [Member] | Level 1 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		0	0
Residential Agency [Member] | Level 2 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		17,431	17,371
Residential Agency [Member] | Level 3 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	[1]	0	0
Residential Non-Agency [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		3	4
Residential Non-Agency [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		3	4
Residential Non-Agency [Member] | Level 1 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		0	0
Residential Non-Agency [Member] | Level 2 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		0	0
Residential Non-Agency [Member] | Level 3 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	[1]	3	4
Commercial Agency [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		3,714	3,463
Commercial Agency [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		3,714	3,463
Commercial Agency [Member] | Level 1 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		0	0
Commercial Agency [Member] | Level 2 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		3,714	3,463
Commercial Agency [Member] | Level 3 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	[1]	0	0
Commercial Non Agency [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		788	1,129
Commercial Non Agency [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		788	1,129
Commercial Non Agency [Member] | Level 1 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		0	0
Commercial Non Agency [Member] | Level 2 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		788	1,129
Commercial Non Agency [Member] | Level 3 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	[1]	0	0
Corporate and other debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		1,108	1,274
Corporate and other debt securities [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		1,108	1,274
Corporate and other debt securities [Member] | Level 1 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		0	0
Corporate and other debt securities [Member] | Level 2 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		1,105	1,271
Corporate and other debt securities [Member] | Level 3 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	[1]	3	3
Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		225	201
Equity Securities [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		225	201
Equity Securities [Member] | Level 1 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		225	201
Equity Securities [Member] | Level 2 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale		0	0
Equity Securities [Member] | Level 3 [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities available for sale	[1]	$ 0	$ 0
[1]	All following disclosures related to Level 3 recurring and non-recurring assets do not include those deemed to be immaterial.

Fair Value Measurements (Rollfo

Fair Value Measurements (Rollforward For Assets And Liabilities Measured At Fair Value On A Recurring Basis With Level 3 Significant Unobservable Inputs) (Details) - Residential Mortgage Servicing Rights [Member] - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening Balance		$ 324	$ 252	$ 257
Gain (Loss) Included in Earnings	[1]	(52)	(36)	(41)
Gain (Loss) Included in Other Comprehensive Income (Loss)		0	0	0
Purchases		64	108	36
Sales		0	0	0
Issuances		0	0	0
Settlements		0	0	0
Transfers Into Level 3		0	0	0
Transfers Out Of Level 3		0	0	0
Closing Balance		$ 336	$ 324	$ 252
[1]	Included in mortgage income.

Fair Value Measurements (Sch133

Fair Value Measurements (Schedule Of Fair Value Adjustments Related To Non-Recurring Fair Value Measurements) (Details) - Nonrecurring Fair Value Measurements [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Loans Held For Sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Adjustment	$ (22)	$ (26)
Foreclosed Property And Other Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Adjustment	$ (31)	$ (42)

Fair Value Measurements (Summar

Fair Value Measurements (Summary Of Quantitative Information About Level 3 Fair Value Measurements) (Details) - Residential Mortgage Servicing Rights [Member] - Discounted Cash Flow [Member] - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Assets, Fair Value Disclosure, Recurring	[1]	$ 336	$ 324	$ 252
Recurring Fair Value Measurements [Member] | Minimum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Prepayment Rate		7.90%	5.70%	10.50%
Option-Adjusted Spread		8.10%	8.20%	8.70%
Recurring Fair Value Measurements [Member] | Maximum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Prepayment Rate		28.10%	24.30%	11.50%
Option-Adjusted Spread		15.00%	13.60%	13.30%
Recurring Fair Value Measurements [Member] | Weighted Average [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Prepayment Rate		9.90%	7.60%	10.90%
Option-Adjusted Spread		8.60%	10.50%	10.00%
[1]	See Note 7 for additional disclosures related to assumptions used in the fair value calculation for residential MSRs.

Fair Value Measurements (Fair V

Fair Value Measurements (Fair Value Option, Fair Value and Unpaid Principal Balance) (Details) - Mortgage loans held for sale [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Option, Quantitative Disclosures [Line Items]
Mortgages Held-for-sale, Fair Value Disclosure	$ 325	$ 447
Fair Value Option Mortgages Held For Sale Aggregate Unpaid Principal	314	443
Aggregate Fair Value Less Aggregate Unpaid Principal	11	4
Net gains (losses) resulting from changes in fair value	$ 5	$ (8)

Fair Value Measurements (Sch136

Fair Value Measurements (Schedule Of Carrying Amounts And Estimated Fair Values Of Financial Instruments) (Details) - USD ($) $ in Millions	Dec. 31, 2017		Dec. 31, 2016
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Trading account securities	$ 189		$ 124
Securities held to maturity, estimated fair value	1,667		1,369
Securities available for sale	23,628		23,781
Loans held for sale, at fair value	325		447
Other earning assets	1,477		1,644
Derivative Assets	253		338
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Derivative Liabilities	403		346
Fair value Discount On Loan Portfolio Amount	$ 1,100		$ 4,100
Fair value Discount On Loan Portfolio Rate	1.40%		5.20%
Capital Leases Carrying Amount Excluded	$ 1,100		$ 876
Property Subject to or Available for Operating Lease, Net	489		688
Carrying Amount [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Cash and cash equivalents	3,981		5,451
Trading account securities	189		124
Securities held to maturity, estimated fair value	1,658		1,362
Securities available for sale	23,628		23,781
Loans held for sale, at fair value	348		718
Net loans (excluding leases)	77,942	[1],[2]	78,128	[3],[4]
Other earning assets	988	[5]	956	[6]
Derivative Assets	394		579
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Derivative Liabilities	641		887
Deposits	96,889		99,035
Short-term Borrowings	500		0
Long-term Borrowings	8,132		7,763
Loan commitments and letters of credit	79		102
Estimate of Fair Value [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Cash and cash equivalents	3,981	[7]	5,451	[8]
Trading account securities	189	[7]	124	[8]
Securities held to maturity, estimated fair value	1,667	[7]	1,369	[8]
Securities available for sale	23,628	[7]	23,781	[8]
Loans held for sale, at fair value	348	[7]	722	[8]
Net loans (excluding leases)	76,871	[7]	74,063	[8]
Other earning assets	988	[7]	956	[8]
Derivative Assets	394	[7]	579	[8]
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Derivative Liabilities	641	[7]	887	[8]
Deposits	96,927	[7]	99,081	[8]
Short-term Borrowings	500	[7]	0	[8]
Long-term Borrowings	8,517	[7]	8,008	[8]
Loan commitments and letters of credit	540	[7]	484	[8]
Level 1 [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Cash and cash equivalents	3,981		5,451
Trading account securities	189		124
Securities held to maturity, estimated fair value	0		0
Securities available for sale	556		504
Loans held for sale, at fair value	0		0
Net loans (excluding leases)	0		0
Other earning assets	0		0
Derivative Assets	2		2
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Derivative Liabilities	2		1
Deposits	0		0
Short-term Borrowings	0		0
Long-term Borrowings	0		0
Loan commitments and letters of credit	0		0
Level 2 [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Cash and cash equivalents	0		0
Trading account securities	0		0
Securities held to maturity, estimated fair value	1,667		1,369
Securities available for sale	23,066		23,270
Loans held for sale, at fair value	328		689
Net loans (excluding leases)	0		0
Other earning assets	988		956
Derivative Assets	387		566
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Derivative Liabilities	639		886
Deposits	96,927		99,081
Short-term Borrowings	500		0
Long-term Borrowings	7,757		5,408
Loan commitments and letters of credit	0		0
Level 3 [Member]
Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract]
Cash and cash equivalents	0		0
Trading account securities	0		0
Securities held to maturity, estimated fair value	0		0
Securities available for sale	6		7
Loans held for sale, at fair value	20		33
Net loans (excluding leases)	76,871		74,063
Other earning assets	0		0
Derivative Assets	5		11
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Derivative Liabilities	0		0
Deposits	0		0
Short-term Borrowings	0		0
Long-term Borrowings	760		2,600
Loan commitments and letters of credit	$ 540		$ 484
[1]	Excluded from this table is the capital lease carrying amount of $1.1 billion at December 31, 2017.
[2]	The estimated fair value of portfolio loans assumes sale of the loans to a third-party financial investor. Accordingly, the value to the Company if the loans were held to maturity is not reflected in the fair value estimate. In the current whole loan market, financial investors are generally requiring a higher rate of return than the return inherent in loans if held to maturity. The fair value discount on the loan portfolio's net carrying amount at December 31, 2017 was $1.1 billion or 1.4 percent.
[3]	Excluded from this table is the capital lease carrying amount of $876 million at December 31, 2016.
[4]	The estimated fair value of portfolio loans assumes sale of the loans to a third-party financial investor. Accordingly, the value to the Company if the loans were held to maturity is not reflected in the fair value estimate. In the current whole loan market, financial investors are generally requiring a higher rate of return than the return inherent in loans if held to maturity. The fair value discount on the loan portfolio's net carrying amount at December 31, 2016 was $4.1 billion or 5.2 percent.
[5]	Excluded from this table is the operating lease carrying amount of $489 million at December 31, 2017.
[6]	Excluded from this table is the operating lease carrying amount of $688 million at December 31, 2016.
[7]	Estimated fair values are consistent with an exit price concept. The assumptions used to estimate the fair values are intended to approximate those that a market participant would use in a hypothetical orderly transaction. In estimating fair value, the Company maintains a corporate governance program to make adjustments for estimated changes in interest rates, market liquidity and credit spreads in the periods they are deemed to have occurred. Historically, the Company has utilized the results of a third-party vendor model to support its primary valuation approach for loans. For the year ended 2017, the Company implemented an internally-supported loan valuation model as its primary valuation approach for loans, including unfunded loan commitments and letters of credit.
[8]	Estimated fair values are consistent with an exit price concept. The assumptions used to estimate the fair values are intended to approximate those that a market participant would use in a hypothetical orderly transaction. In estimating fair value, the Company maintains a corporate governance program to make adjustments for estimated changes in interest rates, market liquidity and credit spreads in the periods they are deemed to have occurred. Historically, the Company has utilized the results of a third-party vendor model to support its primary valuation approach for loans.

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount	$ 0	$ 0	$ 0

Business Segment Information (S

Business Segment Information (Schedule Of Financial Information By Reportable Segment) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Non-interest income		$ 2,105	$ 2,153	$ 2,071
Non-interest expense		3,624	3,617	3,607
Income from continuing operations before income taxes		1,871	1,672	1,530
Income tax expense (benefit)	[1],[2]	614	514	455
Corporate Bank [Member]
Segment Reporting Information [Line Items]
Net interest income and other financing income (loss)		1,422	1,449	1,512
Provision (credit) for loan losses		258	286	301
Non-interest income		467	485	435
Non-interest expense		865	876	887
Income from continuing operations before income taxes		766	772	759
Income tax expense (benefit)		291	293	288
Net income (loss)		475	479	471
Average assets		51,680	54,006	53,308
Consumer Bank [Member]
Segment Reporting Information [Line Items]
Net interest income and other financing income (loss)		2,140	2,047	2,018
Provision (credit) for loan losses		297	290	276
Non-interest income		1,116	1,126	1,074
Non-interest expense		2,051	2,061	2,067
Income from continuing operations before income taxes		908	822	749
Income tax expense (benefit)		345	312	285
Net income (loss)		563	510	464
Average assets		34,997	34,597	33,415
Wealth Management [Member]
Segment Reporting Information [Line Items]
Net interest income and other financing income (loss)		192	175	167
Provision (credit) for loan losses		20	22	22
Non-interest income		450	427	408
Non-interest expense		481	469	458
Income from continuing operations before income taxes		141	111	95
Income tax expense (benefit)		53	42	37
Net income (loss)		88	69	58
Average assets		3,117	3,232	3,185
Other [Member]
Segment Reporting Information [Line Items]
Net interest income and other financing income (loss)		(214)	(273)	(390)
Provision (credit) for loan losses		(425)	(336)	(358)
Non-interest income		72	115	154
Non-interest expense		227	211	195
Income from continuing operations before income taxes		56	(33)	(73)
Income tax expense (benefit)		(75)	(133)	(155)
Net income (loss)		131	100	82
Average assets		34,182	33,671	32,357
Continuing Operations [Member]
Segment Reporting Information [Line Items]
Net interest income and other financing income (loss)		3,540	3,398	3,307
Provision (credit) for loan losses		150	262	241
Non-interest income		2,105	2,153	2,071
Non-interest expense		3,624	3,617	3,607
Income from continuing operations before income taxes		1,871	1,672	1,530
Income tax expense (benefit)		614	514	455
Net income (loss)		1,257	1,158	1,075
Average assets		123,976	125,506	122,265
Discontinued Operations [Member]
Segment Reporting Information [Line Items]
Net interest income and other financing income (loss)		0	0	0
Provision (credit) for loan losses		0	0	0
Non-interest income		0	0	0
Non-interest expense		(8)	(8)	22
Income from continuing operations before income taxes		8	8	(22)
Income tax expense (benefit)		2	3	(9)
Net income (loss)		6	5	(13)
Average assets		0	0	0
Consolidated [Member]
Segment Reporting Information [Line Items]
Net interest income and other financing income (loss)		3,540	3,398	3,307
Provision (credit) for loan losses		150	262	241
Non-interest income		2,105	2,153	2,071
Non-interest expense		3,616	3,609	3,629
Income from continuing operations before income taxes		1,879	1,680	1,508
Income tax expense (benefit)		616	517	446
Net income (loss)		1,263	1,163	1,062
Average assets		$ 123,976	$ 125,506	$ 122,265
[1]	Income tax expense includes amortization of affordable housing investments of $160 million (including $23 million due to impact of Tax Reform), $117 million and $103 million for 2017, 2016 and 2015, respectively. Income tax expense for 2015 includes a benefit of $15 million related to an improved methodology implemented to estimate the effective state tax rate.
[2]	The table above does not include total income tax expense (benefit) from discontinued operations of $2 million, $3 million, and $(9) million in 2017, 2016 and 2015, respectively. The deferred income tax expense reflected in discontinued operations was $1 million, $18 million and $46 million in 2017, 2016 and 2015, respectively.

Commitments, Contingencies a139

Commitments, Contingencies and Guarantees (Credit Risk Of Financial Instruments By Contractual Amounts) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Other Commitments [Line Items]
Unused commitments to extend credit	$ 45,705	$ 44,408
Standby letters of credit	1,348	1,425
Commercial letters of credit	76	46
Liabilities associated with standby letters of credit	26	34
Assets associated with standby letters of credit	28	34
Reserve for unfunded credit commitments	$ 53	$ 69	$ 52	$ 65

Commitments, Contingencies a140

Commitments, Contingencies and Guarantees (Operating Leases) (Details) $ in Millions	Dec. 31, 2017USD ($)
Property Subject to or Available for Operating Lease [Line Items]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	$ 135
Operating Leases, Future Minimum Payments, Due in Two Years	114
Operating Leases, Future Minimum Payments, Due in Three Years	95
Operating Leases, Future Minimum Payments, Due in Four Years	76
Operating Leases, Future Minimum Payments, Due in Five Years	65
Operating Leases, Future Minimum Payments, Due Thereafter	252
Operating Leases, Future Minimum Payments Due	737
Building [Member]
Property Subject to or Available for Operating Lease [Line Items]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	104
Operating Leases, Future Minimum Payments, Due in Two Years	101
Operating Leases, Future Minimum Payments, Due in Three Years	90
Operating Leases, Future Minimum Payments, Due in Four Years	76
Operating Leases, Future Minimum Payments, Due in Five Years	65
Operating Leases, Future Minimum Payments, Due Thereafter	252
Operating Leases, Future Minimum Payments Due	688
Equipment [Member]
Property Subject to or Available for Operating Lease [Line Items]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	31
Operating Leases, Future Minimum Payments, Due in Two Years	13
Operating Leases, Future Minimum Payments, Due in Three Years	5
Operating Leases, Future Minimum Payments, Due in Four Years	0
Operating Leases, Future Minimum Payments, Due in Five Years	0
Operating Leases, Future Minimum Payments, Due Thereafter	0
Operating Leases, Future Minimum Payments Due	$ 49

Commitments, Contingencies a141

Commitments, Contingencies and Guarantees (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Long-term Purchase Commitment [Line Items]
Operating Leases, Rent Expense	$ 167	$ 172	$ 174
Fannie Mae DUS Servicing Portfolio, Amount	2,900	1,800
Maximum Quantifiable Fannie Mae DUS Loss Share Guarantee	923	559
Loss Share Guarantee	$ 4	$ 4

Condensed Financial Information

Condensed Financial Information Parent Company Balance Sheets (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Assets
Interest-bearing deposits in other banks	$ 1,899	$ 3,583
Securities available for sale	23,628	23,781
Premises and equipment, net	2,064	2,096
Other assets	6,182	6,020
Total assets	124,294	125,968
Liabilities and Stockholder's Equity [Abstract]
Long-term borrowings	8,132	7,763
Other liabilities	2,581	2,506
Total liabilities	108,102	109,304
Equity [Abstract]
Preferred Stock, Carrying Amount	820	820
Common stock	12	13
Additional paid-in capital	15,858	17,092
Retained earnings	1,628	666
Treasury Stock, Value	(1,377)	(1,377)
Accumulated other comprehensive income (loss), net	(749)	(550)	$ (380)	$ (238)
Total stockholders’ equity	16,192	16,664	$ 16,844	$ 16,873
Total liabilities and stockholders’ equity	124,294	125,968
Parent Company [Member]
Assets
Interest-bearing deposits in other banks	1,693	1,043
Loans to subsidiaries	20	20
Securities available for sale	18	20
Premises and equipment, net	46	42
Investments in subsidiaries	16,994	17,102
Other assets	303	453
Total assets	19,074	18,680
Liabilities and Stockholder's Equity [Abstract]
Long-term borrowings	2,702	1,728
Other liabilities	180	288
Total liabilities	2,882	2,016
Equity [Abstract]
Preferred Stock, Carrying Amount	820	820
Common stock	12	13
Additional paid-in capital	15,858	17,092
Retained earnings	1,628	666
Treasury Stock, Value	(1,377)	(1,377)
Accumulated other comprehensive income (loss), net	(749)	(550)
Total stockholders’ equity	16,192	16,664
Total liabilities and stockholders’ equity	19,074	18,680
Bank [Member] | Parent Company [Member]
Assets
Investments in subsidiaries	16,548	16,693
Non-Bank [Member] | Parent Company [Member]
Assets
Investments in subsidiaries	$ 446	$ 409

Condensed Financial Informat143

Condensed Financial Information Parent Company Statement of Operations (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Insurance Proceeds		$ 0	$ 50	$ 91
Salaries and employee benefits		1,954	1,913	1,883
Interest expense		373	313	268
Furniture and equipment expense		330	317	303
Professional, legal and regulatory expenses		95	89	137
Income from continuing operations before income taxes		1,871	1,672	1,530
Income tax expense (benefit)	[1],[2]	614	514	455
Income from continuing operations		1,257	1,158	1,075
Income (loss) from discontinued operations before income taxes		8	8	(22)
Income tax expense (benefit)		2	3	(9)
Income (loss) from discontinued operations, net of tax		6	5	(13)
Net income		1,263	1,163	1,062
Preferred stock dividends		(64)	(64)	(64)
Net income available to common shareholders		1,199	1,099	998
Parent Company [Member]
Cash Dividends Paid to Parent Company by Consolidated Subsidiaries		1,300	1,190	860
Interest Income		6	7	7
Insurance Proceeds		0	0	91
Other Income		2	4	0
Revenues		1,308	1,201	958
Salaries and employee benefits		65	56	51
Interest expense		80	73	60
Furniture and equipment expense		4	3	1
Professional, legal and regulatory expenses		0	2	3
Other Expenses		68	89	81
Operating Expenses		217	223	196
Income from continuing operations before income taxes		1,091	978	762
Income tax expense (benefit)		(65)	(66)	(45)
Income from continuing operations		1,156	1,044	807
Income (loss) from discontinued operations before income taxes		8	8	(22)
Income tax expense (benefit)		2	3	(9)
Income (loss) from discontinued operations, net of tax		6	5	(13)
Income before equity in undistributed earnings of subsidiaries and preferred dividends		1,162	1,049	794
Equity in undistributed earnings of subsidiaries:		101	114	268
Net income		1,263	1,163	1,062
Preferred stock dividends		(64)	(64)	(64)
Net income available to common shareholders		1,199	1,099	998
Bank [Member] | Parent Company [Member]
Equity in undistributed earnings of subsidiaries:		73	102	257
Non-Bank [Member] | Parent Company [Member]
Equity in undistributed earnings of subsidiaries:		$ 28	$ 12	$ 11
[1]	Income tax expense includes amortization of affordable housing investments of $160 million (including $23 million due to impact of Tax Reform), $117 million and $103 million for 2017, 2016 and 2015, respectively. Income tax expense for 2015 includes a benefit of $15 million related to an improved methodology implemented to estimate the effective state tax rate.
[2]	The table above does not include total income tax expense (benefit) from discontinued operations of $2 million, $3 million, and $(9) million in 2017, 2016 and 2015, respectively. The deferred income tax expense reflected in discontinued operations was $1 million, $18 million and $46 million in 2017, 2016 and 2015, respectively.

Condensed Financial Informat144

Condensed Financial Information Parent Company Statements of Cash Flow (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating activities:
Net income	$ 1,263	$ 1,163	$ 1,062
Adjustments to reconcile net income to net cash from operating activities:
Depreciation, amortization and accretion, net	537	574	523
(Gain) loss on early extinguishment of debt	0	14	43
Net change in operating assets and liabilities:
Other assets	(405)	(219)	12
Other liabilities	110	189	(449)
Other	47	180	124
Net cash from operating activities	2,281	1,968	1,599
Investing activities:
Proceeds from sales and maturities of securities available for sale	3,649	4,420	3,890
Purchases of securities available for sale	(4,580)	(7,874)	(7,819)
Net cash from investing activities	(785)	(631)	(6,124)
Financing activities:
Proceeds from long-term borrowings	6,649	3,357	5,996
Payments on long-term borrowings	(6,255)	(3,916)	(1,142)
Cash dividends on common stock	(346)	(317)	(304)
Cash dividends on preferred stock	(64)	(64)	(64)
Other	(1,275)	(839)	(623)
Other	(7)	(2)	12
Net cash from financing activities	(2,966)	(1,200)	5,835
Net change in cash and cash equivalents	(1,470)	137	1,310
Cash and cash equivalents at beginning of year	5,451	5,314	4,004
Cash and cash equivalents at end of year	3,981	5,451	5,314
Parent Company [Member]
Operating activities:
Net income	1,263	1,163	1,062
Adjustments to reconcile net income to net cash from operating activities:
Equity in undistributed earnings of subsidiaries	(101)	(114)	(268)
Depreciation, amortization and accretion, net	2	2	1
Loss on sale of assets	1	0	0
(Gain) loss on early extinguishment of debt	0	14	0
Net change in operating assets and liabilities:
Other assets	(19)	33	16
Other liabilities	2	(38)	(213)
Other	41	68	48
Net cash from operating activities	1,189	1,128	646
Investing activities:
(Investment in) / repayment of investment in subsidiaries	141	(60)	(239)
Principal payments received on loans to subsidiaries	0	0	10
Principal advances on loans to subsidiaries	0	(10)	(10)
Proceeds from sales and maturities of securities available for sale	9	8	6
Purchases of securities available for sale	(6)	(8)	(7)
Net (purchases of) / proceeds from sales of assets	6	(1)	(43)
Other, net	2	0	0
Net cash from investing activities	152	(71)	(283)
Financing activities:
Proceeds from long-term borrowings	999	1,107	0
Payments on long-term borrowings	0	(658)	(500)
Cash dividends on common stock	(346)	(317)	(304)
Cash dividends on preferred stock	(64)	(64)	(64)
Other	(1,275)	(839)	(623)
Other	(5)	(2)	12
Net cash from financing activities	(691)	(773)	(1,479)
Net change in cash and cash equivalents	650	284	(1,116)
Cash and cash equivalents at beginning of year	1,043	759	1,875
Cash and cash equivalents at end of year	$ 1,693	$ 1,043	$ 759