Synovus Financial (SNV) 10-Q 7 Nov 17 2017 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2017	Nov. 02, 2017
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q3
Entity Registrant Name	SYNOVUS FINANCIAL CORP
Entity Central Index Key	18,349
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		119,514,829

CONSOLIDATED BALANCE SHEETS (un

CONSOLIDATED BALANCE SHEETS (unaudited) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
ASSETS
Cash and cash equivalents	$ 386,459	$ 395,175
Interest bearing funds with Federal Reserve Bank	1,297,581	527,090
Interest earning deposits with banks	6,047	18,720
Federal funds sold and securities purchased under resale agreements	48,820	58,060
Trading account assets, at fair value	12,329	9,314
Mortgage loans held for sale, at fair value	54,072	51,545
Other loans held for sale	31,253	0
Investment securities available for sale, at fair value	3,825,443	3,718,195
Loans, net of deferred fees and costs	24,487,360	23,856,391
Allowance for loan losses	(249,683)	(251,758)
Loans, net	24,237,677	23,604,633
Premises and equipment, net	423,245	417,485
Goodwill	57,315	59,678
Other intangible assets	11,548	13,223
Other real estate	10,551	22,308
Deferred tax asset, net	272,052	395,356
Other assets	967,731	813,220
Total assets	31,642,123	30,104,002
Deposits:
Non-interest bearing deposits	7,302,682	7,085,804
Interest bearing deposits, excluding brokered deposits	16,420,319	16,183,273
Brokered deposits	2,463,227	1,378,983
Total deposits	26,186,228	24,648,060
Federal funds purchased and securities sold under repurchase agreements	141,539	159,699
Long-term debt	1,882,607	2,160,881
Other liabilities	434,671	207,438
Total liabilities	28,645,045	27,176,078
Shareholders' Equity
Series C Preferred Stock – no par value. Authorized 100,000,000 shares; 5,200,000 shares issued and outstanding at September 30, 2017 and December 31, 2016	125,980	125,980
Common stock - $1.00 par value. Authorized 342,857,143 shares; 142,525,139 issued at September 30, 2017 and 142,025,720 issued at December 31, 2016; 119,566,625 outstanding at September 30, 2017 and 122,266,106 outstanding at December 31, 2016	142,525	142,026
Additional paid-in capital	3,033,682	3,028,405
Treasury stock, at cost – 22,958,514 shares at September 30, 2017 and 19,759,614 shares at December 31, 2016	(800,509)	(664,595)
Accumulated other comprehensive loss	(39,596)	(55,659)
Retained earnings	534,996	351,767
Total shareholders’ equity	2,997,078	2,927,924
Total liabilities and shareholders' equity	$ 31,642,123	$ 30,104,002

CONSOLIDATED BALANCE SHEETS (u3

CONSOLIDATED BALANCE SHEETS (unaudited) (Parenthetical) - $ / shares	Sep. 30, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Preferred Stock, shares authorized	100,000,000	100,000,000
Preferred Stock, shares issued	5,200,000	5,200,000
Preferred stock, shares outstanding	5,200,000	5,200,000
Common stock, par value (per share)	$ 1	$ 1
Common stock, shares authorized	342,857,143	342,857,143
Common stock, shares issued	142,525,139	142,025,720
Common stock, shares outstanding	119,566,625	122,266,106
Treasury stock, shares at cost	22,958,514	19,759,614

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME (unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Interest income:
Loans, including fees	$ 273,847	$ 237,448	$ 785,166	$ 700,340
Investment securities available for sale	20,014	16,269	60,112	49,926
Trading account assets	41	13	90	46
Mortgage loans held for sale	506	727	1,478	1,966
Federal Reserve Bank balances	1,569	1,151	4,084	3,170
Other earning assets	1,675	946	4,633	2,822
Total interest income	297,652	256,554	855,563	758,270
Interest expense:
Deposits	20,798	15,858	55,874	48,072
Federal funds purchased and securities sold under repurchase agreements	42	58	125	154
Long-term debt	14,240	14,631	45,967	44,394
Total interest expense	35,080	30,547	101,966	92,620
Net interest income	262,572	226,007	753,597	665,650
Provision for loan losses	39,686	5,671	58,620	21,741
Net interest income after provision for loan losses	222,886	220,336	694,977	643,909
Non-interest income:
Service charges on deposit accounts	20,255	20,822	59,848	60,772
Fiduciary and asset management fees	12,615	11,837	37,290	34,691
Brokerage revenue	7,511	6,199	21,947	20,019
Mortgage banking income	5,603	7,329	17,151	18,755
Bankcard fees	7,901	8,269	24,339	24,988
Cabela's Transaction Fee	75,000	0	75,000	0
Investment securities (losses) gains, net	(7,956)	59	(289)	126
Decrease in fair value of private equity investments, net	(27)	(249)	(3,193)	(527)
Other fee income	5,094	5,171	16,127	15,255
Other non-interest income	9,439	8,718	27,754	25,109
Total non-interest income	135,435	68,155	275,974	199,188
Non-interest expense:
Salaries and other personnel expense	109,675	101,945	322,079	300,364
Net occupancy and equipment expense	30,573	28,120	89,837	81,480
Third-party processing expense	13,659	11,219	39,882	34,033
FDIC insurance and other regulatory fees	7,078	6,756	20,723	20,100
Professional fees	7,141	6,486	20,048	19,794
Advertising expense	3,610	5,597	14,868	15,358
Foreclosed real estate expense, net	7,265	2,725	10,847	9,998
Earnout liability adjustments	2,059	0	3,766	0
Merger-related expense	23	550	110	550
Loss on early extinguishment of debt, net	0	0	0	4,735
Fair value adjustment to Visa derivative	0	360	0	1,079
Restructuring charges, net	519	1,243	7,043	8,225
Other operating expenses	24,044	20,870	65,577	67,000
Total non-interest expense	205,646	185,871	594,780	562,716
Income before income taxes	152,675	102,620	376,171	280,381
Income tax expense	54,668	37,375	130,303	102,148
Net income	98,007	65,245	245,868	178,233
Dividends on preferred stock	2,559	2,559	7,678	7,678
Net income available to common shareholders	$ 95,448	$ 62,686	$ 238,190	$ 170,555
Net income per common share, basic (in dollars per share)	$ 0.79	$ 0.51	$ 1.96	$ 1.36
Net income per common share, diluted (in dollars per share)	$ 0.78	$ 0.51	$ 1.94	$ 1.36
Weighted average common shares outstanding, basic (in shares)	120,900	122,924	121,796	125,076
Weighted average common shares outstanding, diluted (in shares)	121,814	123,604	122,628	125,712

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income, Before-tax Amount	$ 152,675	$ 102,620	$ 376,171	$ 280,381
Net income, Tax (Expense) Benefit	(54,668)	(37,375)	(130,303)	(102,148)
Net income	98,007	65,245	245,868	178,233
Reclassification adjustment for losses realized in net income, Before-tax Amount	0	65	130	402
Reclassification adjustment for losses realized in net income, Tax (Expense) Benefit	0	(25)	(50)	(155)
Reclassification adjustment for losses realized in net income, Net of Tax Amount	0	40	80	247
Net unrealized gains on investment securities available for sale:
Reclassification adjustment for net losses (gains) realized in net income, Before-tax Amount	7,956	(59)	289	(126)
Net unrealized gains arising during the period, Before-tax Amount	5,465	(9,567)	25,715	56,648
Net unrealized gain, Before-tax Amount	13,421	(9,626)	26,004	56,522
Net unrealized gains on investment securities available for sale: Tax (Expense) Benefit
Reclassification adjustment for net losses (gains) realized in net income, Tax (Expense) Benefit	(3,063)	23	(111)	49
Net unrealized gains arising during the period, Tax (Expense) Benefit	(2,106)	3,672	(9,903)	(21,821)
Net unrealized gains, Tax (Expense) Benefit	(5,169)	3,695	(10,014)	(21,772)
Net unrealized gains on investment securities available for sale: Net of Tax Amount
Reclassification adjustment for net losses (gains) realized in net income, Net of Tax Amount	4,893	(36)	178	(77)
Net unrealized gains arising during the period, Net of Tax Amount	3,359	(5,895)	15,812	34,827
Net unrealized gains, Net of Tax Amount	8,252	(5,931)	15,990	34,750
Post-retirement unfunded health benefit: Before-tax Amount
Reclassification adjustment for gains realized in net income, Before-tax Amount	(34)	(20)	(74)	(124)
Actuarial gains arising during the period, Before-tax Amount	61	102	61	102
Net unrealized (realized) gains, Before-tax Amount	27	82	(13)	(22)
Post-retirement unfunded health benefit: Tax (Expense) Benefit
Reclassification adjustment for gains realized in net income, Tax (Expense) Benefit	13	8	29	48
Actuarial gains arising during the period, Tax (Expense) Benefit	(23)	(39)	(23)	(39)
Net unrealized (realized) gains, Tax (Expense) Benefit	(10)	(31)	6	9
Post-retirement unfunded health benefit: Net of Tax Amount
Reclassification adjustment for gains realized in net income, Net of Tax Amount	(21)	(12)	(45)	(76)
Actuarial gains arising during the period, Net of Tax Amount	38	63	38	63
Net unrealized (realized) gains, Net of Tax Amount	17	51	(7)	(13)
Other comprehensive income (loss), Before-tax Amount	13,448	(9,479)	26,121	56,902
Other comprehensive income (loss), Tax (Expense) Benefit	(5,179)	3,639	(10,058)	(21,918)
Other comprehensive income (loss), Net of Tax Amount	8,269	(5,840)	16,063	34,984
Comprehensive income, Net of Tax Amount	$ 106,276	$ 59,405	$ 261,931	$ 213,217

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (unaudited) - USD ($) $ in Thousands	Total	Preferred StockSeries C Preferred Stock	Common Stock	Additional Paid-in Capital	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Retained Earnings
Balance at Dec. 31, 2015	$ 3,000,196	$ 125,980	$ 140,592	$ 2,989,981	$ (401,511)	$ (29,819)	$ 174,973
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	178,233						178,233
Other comprehensive income, net of income taxes	34,984					34,984
Cash dividends declared on common stock	(44,737)						(44,737)
Cash dividends paid on Series C Preferred Stock	(7,678)						(7,678)
Repurchases of common stock	(263,084)			(10,581)	(252,503)
Restricted share unit activity	(4,648)		301	(4,860)			(89)
Stock options exercised	2,981		173	2,808
Share-based compensation net tax benefit	199			199
Share-based compensation expense	10,213			10,213
Balance at Sep. 30, 2016	2,906,659	125,980	141,066	2,987,760	(654,014)	5,165	300,702
Balance at Jun. 30, 2016						11,005
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income, net of income taxes	(5,840)					(5,840)
Balance at Sep. 30, 2016	2,906,659	125,980	141,066	2,987,760	(654,014)	5,165	300,702
Balance at Dec. 31, 2016	2,927,924	125,980	142,026	3,028,405	(664,595)	(55,659)	351,767
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	245,868						245,868
Other comprehensive income, net of income taxes	16,063					16,063
Cash dividends declared on common stock	(54,671)						(54,671)
Cash dividends paid on Series C Preferred Stock	(7,678)						(7,678)
Repurchases of common stock	(135,914)				(135,914)
Restricted share unit activity	(7,962)		335	(8,007)			(290)
Stock options exercised	2,872		164	2,708
Share-based compensation expense	10,576			10,576
Balance at Sep. 30, 2017	2,997,078	125,980	142,525	3,033,682	(800,509)	(39,596)	534,996
Balance at Jun. 30, 2017						(47,865)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income, net of income taxes	8,269					8,269
Balance at Sep. 30, 2017	$ 2,997,078	$ 125,980	$ 142,525	$ 3,033,682	$ (800,509)	$ (39,596)	$ 534,996

CONSOLIDATED STATEMENTS OF CHA7

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (unaudited) (Parenthetical) - $ / shares	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Statement of Stockholders' Equity [Abstract]
Cash dividends declared on common stock, per share	$ 0.45	$ 0.36

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS (unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Operating Activities
Net income	$ 245,868	$ 178,233
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	58,620	21,741
Depreciation, amortization, and accretion, net	44,786	43,615
Deferred income tax expense	114,205	94,436
Decrease in trading account assets	(3,014)	(2,212)
Originations of mortgage loans held for sale	(490,202)	(512,572)
Proceeds from sales of mortgage loans held for sale	500,786	486,690
Gain on sales of mortgage loans held for sale, net	(10,587)	(10,828)
Increase in other assets	(18,598)	(38,577)
Increase in other liabilities	17,718	37,068
Investment securities losses (gains), net	289	(126)
Losses and write-downs on other real estate, net	9,869	8,194
Decrease in fair value of private equity investments, net	3,193	527
Losses and write-downs on other assets held for sale, net	1,872	7,205
Loss on early extinguishment of debt, net	0	4,735
Share-based compensation expense	10,576	10,213
Net cash provided by operating activities	485,381	328,342
Investing Activities
Net decrease (increase) in interest earning deposits with banks	12,673	(988)
Net decrease (increase) in federal funds sold and securities purchased under resale agreements	9,240	(1,934)
Net increase in interest bearing funds with Federal Reserve Bank	(770,491)	(155,889)
Proceeds from maturities and principal collections of investment securities available for sale	483,307	711,882
Proceeds from sales of investment securities available for sale	812,293	596,824
Purchases of investment securities available for sale	(1,195,302)	(1,233,236)
Proceeds from sales of loans	26,386	8,433
Proceeds from sales of other real estate	8,359	25,415
Net increase in loans	(755,231)	(879,200)
Purchases of bank-owned life insurance policies	(150,000)	0
Net increase in premises and equipment	(34,717)	(24,491)
Proceeds from sales of other assets held for sale	3,158	5,673
Net cash used in investing activities	(1,550,325)	(947,511)
Financing Activities
Net increase in demand and savings deposits	335,438	1,054,389
Net increase (decrease) in certificates of deposit	1,202,926	(105,698)
Net (decrease) increase in federal funds purchased and securities sold under repurchase agreements	(18,160)	18,000
Repayments on long-term debt	(1,653,613)	(1,730,106)
Proceeds from issuance of long-term debt	1,375,000	1,700,000
Dividends paid to common shareholders	(36,681)	(44,737)
Dividends paid to preferred shareholders	(7,678)	(7,678)
Stock options exercised	2,872	2,981
Repurchases of common stock	(135,914)	(263,084)
Restricted stock activity	(7,962)	(4,648)
Net cash provided by financing activities	1,056,228	619,419
(Decrease) increase in cash and cash equivalents	(8,716)	250
Cash and cash equivalents at beginning of period	395,175	367,092
Cash and cash equivalents at end of period	386,459	367,342
Supplemental Cash Flow Information
Income tax payments, net	11,195	6,828
Interest paid	101,632	93,479
Non-cash Activities
Premises and equipment transferred to other assets held for sale	1,063	23,667
Other assets held for sale transferred to premises and equipment	4,450	0
Loans foreclosed and transferred to other real estate	6,571	15,017
Loans transferred to other loans held for sale at fair value	77,774	10,482
Securities purchased during the period but settled after period-end	193,286	49,479
Dividends declared on common stock during the period but paid after period-end	$ 17,990	$ 0

Significant Accounting Policies

Significant Accounting Policies	9 Months Ended
	Sep. 30, 2017
Accounting Policies [Abstract]
Significant Accounting Policies	Note 1 - Significant Accounting Policies Business Operations The accompanying unaudited interim consolidated financial statements of Synovus Financial Corp. include the accounts of the Parent Company and its consolidated subsidiaries. Synovus Financial Corp. is a financial services company based in Columbus, Georgia. Through its wholly-owned subsidiary, Synovus Bank, a Georgia state-chartered bank that is a member of the Federal Reserve System, the company provides commercial and retail banking in addition to a full suite of specialized products and services including private banking, treasury management, wealth management, premium finance and international banking. Synovus Bank is positioned in some of the highest growth markets in the Southeast, with 249 branches and 328 ATMs in Georgia, Alabama, South Carolina, Florida, and Tennessee. Basis of Presentation The accompanying unaudited interim consolidated financial statements have been prepared in accordance with the instructions to the SEC Form 10-Q and Article 10 of Regulation S-X; therefore, they do not include all information and footnotes necessary for a fair presentation of financial position, results of operations, comprehensive income, and cash flows in conformity with GAAP. All adjustments consisting of normally recurring accruals that, in the opinion of management, are necessary for a fair presentation of the consolidated financial position and results of operations for the periods covered by this Report have been included. The accompanying unaudited interim consolidated financial statements should be read in conjunction with the consolidated financial statements and related notes appearing in Synovus' 2016 Form 10-K. There have been no significant changes to the accounting policies as disclosed in Synovus' 2016 Form 10-K. In preparing the unaudited interim consolidated financial statements in accordance with GAAP, management is required to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities as of the date of the respective consolidated balance sheets and the reported amounts of revenues and expenses for the periods presented. Actual results could differ significantly from those estimates. Material estimates that are particularly susceptible to significant change relate to the determination of the allowance for loan losses, the fair value of investment securities, and the fair value of private equity investments. Cash and Cash Equivalents Cash and cash equivalents consist of cash and due from banks. At December 31, 2016 , $ 533 thousand of the due from banks balance was restricted as to withdrawal. There were no cash and cash equivalents restricted as to withdrawal at September 30, 2017. Short-term Investments Short-term investments consist of interest bearing funds with the Federal Reserve Bank, interest earning deposits with banks, and federal funds sold and securities purchased under resale agreements. At September 30, 2017 and December 31, 2016 , interest bearing funds with the Federal Reserve Bank included $57.7 million and $130.0 million , respectively, on deposit to meet Federal Reserve Bank requirements. Interest earning deposits with banks include $6.0 million and $5.6 million at September 30, 2017 and December 31, 2016 , respectively, which are pledged as collateral in connection with certain letters of credit. Federal funds sold include $45.8 million and $56.1 million at September 30, 2017 and December 31, 2016 , respectively, which are pledged to collateralize certain derivative financial instruments. Federal funds sold and securities purchased under resale agreements, and federal funds purchased and securities sold under repurchase agreements, generally mature in one day. Recently Adopted Accounting Standards Updates During 2016, the FASB issued ASU 2016-09, Compensation-Stock Compensation: Improvements to Employee Share-Based Payment Accounting. ASU 2016-09 simplified various aspects of the accounting for employee share-based payment transactions for both public and nonpublic entities, including the accounting for income taxes, forfeitures, and statutory tax withholding requirements, as well as classification in the statement of cash flows. This accounting standard update included a requirement to record all tax effects associated with share-based compensation through the income statement. Prior to 2017, tax benefits in excess of compensation cost (“windfalls”) and tax deficiencies (“shortfalls”) were recorded in equity. During the nine and three months ended September 30, 2017 , Synovus recognized $4.7 million and $211 thousand , respectively, of income tax benefits from excess tax benefits that occurred during the nine months ended September 30, 2017 from the vesting of restricted share units and exercise of stock options. As of January 1, 2017, Synovus had no previously unrecognized excess tax benefits. Additionally, beginning January 1, 2017, Synovus modified the denominator in the diluted earnings per common share calculation under the treasury stock method to exclude future excess tax benefits as part of the assumed proceeds. Synovus elected to retain its existing accounting policy election to estimate award forfeitures. During 2015, the FASB issued ASU 2015-17, Income Taxes: Balance Sheet Classification of Deferred Taxes , which became effective January 1, 2017. ASU 2015-17 required deferred income tax liabilities and assets be classified as noncurrent in the statement of financial position instead of separating deferred taxes into current and noncurrent amounts. Also, valuation allowances will no longer be classified between current and noncurrent because these allowances will be required to be classified as noncurrent under the new standard. This ASU only impacts classification in the balance sheet, and has no impact on required deferred tax footnote disclosures (i.e., required presentation of “gross” deferred tax assets and “gross” deferred tax liabilities). The current requirement that deferred tax liabilities and assets of a tax-paying component of an entity be offset and presented as a single amount is not affected by this ASU. There is no impact to our balance sheet as a result of this standard because Synovus has not historically distinguished deferred taxes on the balance sheet as current vs. non-current. Reclassifications Prior periods' consolidated financial statements are reclassified whenever necessary to conform to the current periods' presentation.

Acquisitions

Acquisitions	9 Months Ended
	Sep. 30, 2017
Business Combinations [Abstract]
Acquisition	Note 2 - Acquisitions Cabela's Transaction On September 25, 2017, Synovus' wholly owned subsidiary, Synovus Bank, completed the acquisition of certain assets and assumption of certain liabilities of WFB. Immediately following the closing of this transaction, Synovus Bank sold WFB’s credit card assets and related liabilities to Capital One Bank (USA), National Association, a bank subsidiary of Capital One Financial Corporation. Synovus retained WFB’s $1.10 billion brokered time deposits portfolio, which had a weighted average remaining maturity of approximately 2.53 years and a weighted average rate of 1.83% as of September 25, 2017. The transaction was accounted for as an assumption of a liability (accounted for under the asset acquisition model). In accordance with ASC 820, Fair Value Measurements and Disclosures, the brokered time deposit portfolio was recorded at $1.10 billion , which was the amount of cash received for the deposits and represented the estimated fair value of the deposits at the transaction date. Additionally, Synovus received a $75.0 million transaction fee from Cabela’s and Capital One, which was recognized into earnings upon closing of the transaction, based on having achieved the recognition criteria outlined in SEC SAB Topic 13.A, Revenue Recognition . Acquisition of Global One On October 1, 2016, Synovus completed its acquisition of all of the outstanding stock of Global One. Prior to its acquisition, Global One was an Atlanta-based private specialty financial services company that lended primarily to commercial entities, with all loans fully collateralized by cash value life insurance policies and/or annuities issued by investment grade life insurance companies. Under the terms of the merger agreement, Synovus acquired Global One for an up-front payment of $30 million , consisting of the issuance of 821 thousand shares of Synovus common stock valued at $26.6 million and $3.4 million in cash, with additional payments to Global One's former shareholders over the next three to five years based on earnings from the Global One business as further discussed below. The acquisition of Global One constituted a business combination. Accordingly, the assets acquired and liabilities assumed were recorded at their estimated fair values as shown in the following table. The determination of fair value required management to make estimates about discount rates, future expected earnings and cash flows, market conditions, future loan growth, and other future events that are highly subjective in nature and subject to change. These fair value estimates reflect measurement period adjustments to the amounts reported as of December 31, 2016, the most significant of which consist of a reduction in goodwill of $2.4 million and a decrease in the estimated fair value of contingent consideration of $1.8 million (the income statement impact of such adjustments was insignificant). Global One October 1, 2016 (in thousands) Fair Value Assets acquired: Cash and due from banks $ 9,554 Commercial and industrial loans (1) 357,307 Goodwill (2) 32,884 Other intangible assets 12,500 Other assets 3,681 Total assets acquired $ 415,926 Liabilities assumed: Notes payable (3) $ 358,560 Contingent consideration 12,234 Deferred tax liability, net 3,229 Other liabilities 11,903 Total liabilities assumed $ 385,926 Consideration paid $ 30,000 Cash paid $ 3,408 Fair value of common stock issued 26,592 (1) The unpaid principal balance of the loans was $356.7 million . (2) The goodwill is not expected to be deductible for tax purposes. (3) The unpaid principal balance of the notes payable was $357.0 million . Under the terms of the merger agreement, the purchase price includes additional annual payments ("Earnout Payments") to Global One's former shareholders over the next three to five years, with amounts based on a percentage of "Global One Earnings," as defined in the merger agreement. The Earnout Payments will consist of shares of Synovus common stock as well as a smaller cash consideration component. Other intangible assets consist of existing borrower relationships ( 11 years useful life), trade name ( 10 years useful life), and distribution network ( 8 years useful life) with September 30, 2017 net carrying values of $9.8 million , $990 thousand , and $525 thousand , respectively. The following is a description of the methods used to determine the fair values of significant assets and liabilities: Commercial and industrial loans : The fair value of loans was determined based on a discounted cash flow approach. The most significant assumptions used in the valuation of the loan portfolio consisted of the prepayment rate, the probability of extension at maturity, the interest rates on extended loans, and the discount rates. All loans are fully collateralized by cash value life insurance policies and/or annuities issued by investment grade insurance companies. Based on a history of no principal losses on the loan portfolio since inception as well as the collateral position, no losses were estimated in the event of default. Notes payable : The notes payable were extinguished immediately after the closing of the acquisition. Accordingly, the fair value of notes payable was determined based on the amounts paid to extinguish such notes, inclusive of applicable prepayment penalties, which is consistent with the perspective of a market participant. Contingent consideration : The fair value of the contingent consideration, which represents the fair value of the above referenced Earnout Payments, was determined based on option pricing methods and a Monte Carlo simulation. The most significant assumptions used in the valuation of the contingent consideration were the expected cash flows, volatility, and discount rates. Subsequent changes in the fair value of the contingent consideration are recognized in earnings until the contingent consideration arrangement is settled.

Share Repurchase Program

Share Repurchase Program	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Share Repurchase Program	Note 3 - Share Repurchase Program Synovus' Board of Directors authorized an up to $200 million share repurchase program that will expire at the end of 2017. This program was announced on January 17, 2017. As of September 30, 2017 , Synovus had repurchased under this program a total of $135.9 million , or 3.2 million shares, at an average price of $42.47 per share.

Investment Securities

Investment Securities	9 Months Ended
	Sep. 30, 2017
Investments [Abstract]
Investment Securities	Note 4 - Investment Securities The amortized cost, gross unrealized gains and losses, and estimated fair values of investment securities available for sale at September 30, 2017 and December 31, 2016 are summarized below. September 30, 2017 (in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury securities $ 83,550 — (369 ) 83,181 U.S. Government agency securities 10,772 266 — 11,038 Mortgage-backed securities issued by U.S. Government agencies 127,521 715 (852 ) 127,384 Mortgage-backed securities issued by U.S. Government sponsored enterprises 2,663,959 7,917 (20,024 ) 2,651,852 Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises 943,583 — (12,143 ) 931,440 State and municipal securities 180 1 — 181 Corporate debt and other securities 20,297 286 (216 ) 20,367 Total investment securities available for sale $ 3,849,862 9,185 (33,604 ) 3,825,443 December 31, 2016 (in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury securities $ 108,221 225 (644 ) 107,802 U.S. Government agency securities 12,727 266 — 12,993 Mortgage-backed securities issued by U.S. Government agencies 174,440 1,116 (1,354 ) 174,202 Mortgage-backed securities issued by U.S. Government sponsored enterprises 2,543,495 5,416 (42,571 ) 2,506,340 Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises 905,789 1,214 (16,561 ) 890,442 State and municipal securities 2,780 14 — 2,794 Equity securities 919 2,863 — 3,782 Corporate debt and other securities 20,247 — (407 ) 19,840 Total investment securities available for sale $ 3,768,618 11,114 (61,537 ) 3,718,195 At September 30, 2017 and December 31, 2016 , investment securities with a carrying value of $1.69 billion and $2.04 billion , respectively, were pledged to secure certain deposits and securities sold under repurchase agreements as required by law and contractual agreements. Synovus has reviewed investment securities that are in an unrealized loss position as of September 30, 2017 and December 31, 2016 for OTTI and does not consider any securities in an unrealized loss position to be other-than-temporarily impaired. If Synovus intended to sell a security in an unrealized loss position, the entire unrealized loss would be reflected in earnings. Synovus does not intend to sell investment securities in an unrealized loss position prior to the recovery of the unrealized loss, which may not be until maturity, and has the ability and intent to hold those securities for that period of time. Additionally, Synovus is not currently aware of any circumstances which will require it to sell any of the securities that are in an unrealized loss position prior to the respective securities' recovery of all such unrealized losses. Declines in the fair value of available for sale securities below their cost that are deemed to have OTTI are reflected in earnings as realized losses to the extent the impairment is related to credit losses. The amount of the impairment related to other factors is recognized in other comprehensive income. Currently, unrealized losses on debt securities are attributable to increases in interest rates on comparable securities from the date of purchase. Synovus regularly evaluates its investment securities portfolio to ensure that there are no conditions that would indicate that unrealized losses represent OTTI. These factors include the length of time the security has been in a loss position, the extent that the fair value is below amortized cost, and the credit standing of the issuer. As of September 30, 2017 , Synovus had 75 investment securities in a loss position for less than twelve months and 13 investment securities in a loss position for twelve months or longer. Gross unrealized losses on investment securities and the fair value of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, at September 30, 2017 and December 31, 2016 are presented below. September 30, 2017 Less than 12 Months 12 Months or Longer Total (in thousands) Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses U.S. Treasury securities $ 64,351 369 — — 64,351 369 Mortgage-backed securities issued by U.S. Government agencies 80,303 552 7,636 300 87,939 852 Mortgage-backed securities issued by U.S. Government sponsored enterprises 1,696,906 19,128 48,596 896 1,745,502 20,024 Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises 569,191 5,617 240,355 6,526 809,546 12,143 Corporate debt and other securities — — 5,081 216 5,081 216 Total $ 2,410,751 25,666 301,668 7,938 2,712,419 33,604 December 31, 2016 Less than 12 Months 12 Months or Longer Total (in thousands) Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses U.S. Treasury securities $ 64,023 644 — — 64,023 644 Mortgage-backed securities issued by U.S. Government agencies 128,121 1,240 3,626 114 131,747 1,354 Mortgage-backed securities issued by U.S. Government sponsored enterprises 2,123,181 42,571 — — 2,123,181 42,571 Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises 682,492 15,653 24,801 908 707,293 16,561 Corporate debt and other securities 14,952 48 4,888 359 19,840 407 Total $ 3,012,769 60,156 33,315 1,381 3,046,084 61,537 The amortized cost and fair value by contractual maturity of investment securities available for sale at September 30, 2017 are shown below. The expected life of mortgage-backed securities or CMOs may differ from contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties. For purposes of the maturity table, mortgage-backed securities and CMOs, which are not due at a single maturity date, have been classified based on the final contractual maturity date. Distribution of Maturities at September 30, 2017 (in thousands) Within One Year 1 to 5 Years 5 to 10 Years More Than 10 Years No Stated Maturity Total Amortized Cost U.S. Treasury securities $ 18,830 64,720 — — — 83,550 U.S. Government agency securities 2,331 6,437 2,004 — — 10,772 Mortgage-backed securities issued by U.S. Government agencies — — 32,956 94,565 — 127,521 Mortgage-backed securities issued by U.S. Government sponsored enterprises 44 2,015 446,255 2,215,645 — 2,663,959 Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises — — 20,910 922,673 — 943,583 State and municipal securities 180 — — — — 180 Corporate debt and other securities — — 15,000 2,000 3,297 20,297 Total amortized cost $ 21,385 73,172 517,125 3,234,883 3,297 3,849,862 Fair Value U.S. Treasury securities $ 18,830 64,351 — — — 83,181 U.S. Government agency securities 2,385 6,529 2,124 — — 11,038 Mortgage-backed securities issued by U.S. Government agencies — — 33,073 94,311 — 127,384 Mortgage-backed securities issued by U.S. Government sponsored enterprises 45 2,127 444,701 2,204,979 — 2,651,852 Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises — — 20,666 910,774 — 931,440 State and municipal securities 181 — — — — 181 Corporate debt and other securities — — 15,286 1,919 3,162 20,367 Total fair value $ 21,441 73,007 515,850 3,211,983 3,162 3,825,443 Proceeds from sales, gross gains, and gross losses on sales of securities available for sale for the nine and three months ended September 30, 2017 and 2016 are presented below. The specific identification method is used to reclassify gains and losses out of other comprehensive income at the time of sale. Nine Months Ended September 30, Three Months Ended September 30, (in thousands) 2017 2016 2017 2016 Proceeds from sales of investment securities available for sale $ 812,293 596,824 $ 473,912 353,215 Gross realized gains on sales 7,942 2,590 — 1,635 Gross realized losses on sales (8,231 ) (2,464 ) (7,956 ) (1,576 ) Investment securities (losses) gains, net $ (289 ) 126 $ (7,956 ) 59

Restructuring Charges

Restructuring Charges	9 Months Ended
	Sep. 30, 2017
Restructuring Charges [Abstract]
Restructuring Charges	Note 5 - Restructuring Charges For the nine and three months ended September 30, 2017 and 2016 , total restructuring charges consist of the following components: Nine Months Ended September 30, Three Months Ended September 30, (in thousands) 2017 2016 2017 2016 Severance charges $ 6,428 — $ (24 ) — Asset impairment charges 511 8,120 515 1,240 Other charges 104 105 28 3 Total restructuring charges, net $ 7,043 8,225 $ 519 1,243 Restructuring charges of $7.0 million were recorded during the nine months ended September 30, 2017 consisting primarily of severance charges of $6.4 million recorded during the first quarter of 2017. Severance charges included $6.2 million for termination benefits incurred in conjunction with a voluntary early retirement program offered during the first quarter of 2017. This program was part of Synovus' ongoing efficiency initiatives. The $6.2 million accrual was based on the benefits to be paid to employees who accepted the early retirement offer on or prior to the expiration of the program on March 30, 2017. The accrual balance for severance charges associated with the voluntary early retirement program was $1.2 million at September 30, 2017. For the three months ended September 30, 2017 , Synovus recorded restructuring charges of $519 thousand due to additional asset impairment charges of $515 thousand on properties previously identified for disposition. During the nine months ended September 30, 2016, Synovus recorded restructuring charges of $8.2 million with $4.8 million of those charges related to corporate real estate optimization activities and $3.3 million associated with branch closures. The following tables present aggregate activity within the accrual for restructuring charges for the nine and three months ended September 30, 2017 and 2016 : (in thousands) Severance Charges Lease Termination Charges Total Balance at December 31, 2016 $ 81 3,968 4,049 Accruals for voluntary and involuntary termination benefits 6,428 — 6,428 Payments (5,304 ) (540 ) (5,844 ) Balance at September 30, 2017 $ 1,205 3,428 4,633 Balance at July 1, 2017 3,731 3,530 7,261 Accruals for voluntary and involuntary termination benefits (24 ) — (24 ) Payments (2,502 ) (102 ) (2,604 ) Balance at September 30, 2017 $ 1,205 3,428 4,633 (in thousands) Severance Charges Lease Termination Charges Total Balance at December 31, 2015 $ 1,930 4,687 6,617 Accruals for lease terminations — 6 6 Payments (1,702 ) (533 ) (2,235 ) Balance at September 30, 2016 $ 228 4,160 4,388 Balance at July 1, 2016 593 4,375 4,968 Accruals for lease terminations — (25 ) (25 ) Payments (365 ) (190 ) (555 ) Balance at September 30, 2016 $ 228 4,160 4,388 All other charges were paid in the quarters that they were incurred. No other restructuring charges resulted in payment accruals.

Loans and Allowance for Loan Lo

Loans and Allowance for Loan Losses	9 Months Ended
	Sep. 30, 2017
Loans and Allowance for Loan Losses [Abstract]
Loans and Allowance for Loan Losses	Note 6 - Loans and Allowance for Loan Losses The following is a summary of current, accruing past due, and non-accrual loans by portfolio class as of September 30, 2017 and December 31, 2016 . Current, Accruing Past Due, and Non-accrual Loans September 30, 2017 (in thousands) Current Accruing 30-89 Days Past Due Accruing 90 Days or Greater Past Due Total Accruing Past Due Non-accrual Total Investment properties $ 5,919,393 3,454 186 3,640 2,063 5,925,096 1-4 family properties 784,520 6,588 796 7,384 2,712 794,616 Land and development 494,488 5,732 65 5,797 6,927 507,212 Total commercial real estate 7,198,401 15,774 1,047 16,821 11,702 7,226,924 Commercial, financial and agricultural 6,871,204 30,010 2,356 32,366 58,139 6,961,709 Owner-occupied 4,751,269 9,586 618 10,204 3,960 4,765,433 Total commercial and industrial 11,622,473 39,596 2,974 42,570 62,099 11,727,142 Home equity lines 1,505,556 7,535 160 7,695 15,638 1,528,889 Consumer mortgages 2,545,986 5,225 137 5,362 6,332 2,557,680 Credit cards 222,176 2,312 1,237 3,549 — 225,725 Other consumer loans 1,234,355 8,726 130 8,856 2,067 1,245,278 Total consumer 5,508,073 23,798 1,664 25,462 24,037 5,557,572 Total loans $ 24,328,947 79,168 5,685 84,853 97,838 24,511,638 (1 ) December 31, 2016 (in thousands) Current Accruing 30-89 Days Past Due Accruing 90 Days or Greater Past Due Total Accruing Past Due Non-accrual Total Investment properties $ 5,861,198 2,795 — 2,795 5,268 5,869,261 1-4 family properties 873,231 4,801 161 4,962 9,114 887,307 Land and development 598,624 1,441 — 1,441 16,233 616,298 Total commercial real estate 7,333,053 9,037 161 9,198 30,615 7,372,866 Commercial, financial and agricultural 6,839,699 9,542 720 10,262 59,074 6,909,035 Owner-occupied 4,601,356 17,913 244 18,157 16,503 4,636,016 Total commercial and industrial 11,441,055 27,455 964 28,419 75,577 11,545,051 Home equity lines 1,585,228 10,013 473 10,486 21,551 1,617,265 Consumer mortgages 2,265,966 7,876 81 7,957 22,681 2,296,604 Credit cards 229,177 1,819 1,417 3,236 — 232,413 Other consumer loans 809,419 5,771 39 5,810 2,954 818,183 Total consumer 4,889,790 25,479 2,010 27,489 47,186 4,964,465 Total loans $ 23,663,898 61,971 3,135 65,106 153,378 23,882,382 (2 ) (1) Total before net deferred fees and costs of $24.3 million . (2) Total before net deferred fees and costs of $26.0 million . The credit quality of the loan portfolio is reviewed and updated no less frequently than quarterly using the standard asset classification system utilized by the federal banking agencies. These classifications are divided into three groups – Not Criticized (Pass), Special Mention, and Classified or Adverse rating (Substandard, Doubtful, and Loss) and are defined as follows: Pass - loans which are well protected by the current net worth and paying capacity of the obligor (or guarantors, if any) or by the fair value, less cost to acquire and sell in a timely manner, of any underlying collateral. Special Mention - loans which have potential weaknesses that deserve management's close attention. These loans are not adversely classified and do not expose an institution to sufficient risk to warrant an adverse classification. Substandard - loans which are inadequately protected by the current net worth and paying capacity of the obligor or by the collateral pledged, if any. Loans with this classification are characterized by the distinct possibility that the institution will sustain some loss if the deficiencies are not corrected. Doubtful - loans which have all the weaknesses inherent in loans classified as Substandard with the added characteristic that the weaknesses make collection or liquidation in full highly questionable and improbable on the basis of currently known facts, conditions, and values. Loss - loans which are considered by management to be uncollectible and of such little value that their continuance on the institution's books as an asset, without establishment of a specific valuation allowance or charge-off, is not warranted. In the following tables, consumer loans are generally assigned a risk grade similar to the classifications described above; however, upon reaching 90 days and 120 days past due, they are generally downgraded to Substandard and Loss, respectively, in accordance with the FFIEC Uniform Retail Credit Classification and Account Management Policy. Additionally, in accordance with the Interagency Supervisory Guidance on Allowance for Loan and Lease Losses Estimation Practices for Loans and Lines of Credit Secured by Junior Liens on 1-4 Family Residential Properties, the risk grade classifications of consumer loans (home equity lines and consumer mortgages) secured by junior liens on 1-4 family residential properties also consider available information on the payment status of any associated senior liens with other financial institutions. Loan Portfolio Credit Exposure by Risk Grade September 30, 2017 (in thousands) Pass Special Mention Substandard (1) Doubtful (2) Loss Total Investment properties $ 5,847,902 60,423 16,771 — — 5,925,096 1-4 family properties 756,665 20,286 17,438 227 — 794,616 Land and development 451,141 36,523 16,419 3,129 — 507,212 Total commercial real estate 7,055,708 117,232 50,628 3,356 — 7,226,924 Commercial, financial and agricultural 6,704,805 106,117 149,456 1,250 81 (3) 6,961,709 Owner-occupied 4,632,930 52,797 79,633 73 — 4,765,433 Total commercial and industrial 11,337,735 158,914 229,089 1,323 81 11,727,142 Home equity lines 1,505,724 — 20,771 355 2,039 (3) 1,528,889 Consumer mortgages 2,547,272 — 10,125 177 106 (3) 2,557,680 Credit cards 224,488 — 523 — 714 (4) 225,725 Other consumer loans 1,242,211 — 2,754 299 14 (3) 1,245,278 Total consumer 5,519,695 — 34,173 831 2,873 5,557,572 Total loans $ 23,913,138 276,146 313,890 5,510 2,954 24,511,638 (5 ) December 31, 2016 (in thousands) Pass Special Mention Substandard (1) Doubtful (2) Loss Total Investment properties $ 5,794,626 43,336 31,299 — — 5,869,261 1-4 family properties 826,311 33,928 26,790 278 — 887,307 Land and development 521,745 60,205 27,361 6,987 — 616,298 Total commercial real estate 7,142,682 137,469 85,450 7,265 — 7,372,866 Commercial, financial and agricultural 6,635,756 126,268 140,425 6,445 141 (3) 6,909,035 Owner-occupied 4,462,420 60,856 111,330 1,410 — 4,636,016 Total commercial and industrial 11,098,176 187,124 251,755 7,855 141 11,545,051 Home equity lines 1,589,199 — 22,774 2,892 2,400 (3) 1,617,265 Consumer mortgages 2,271,916 — 23,268 1,283 137 (3) 2,296,604 Credit cards 230,997 — 637 — 779 (4) 232,413 Other consumer loans 814,844 — 3,233 42 64 (3) 818,183 Total consumer 4,906,956 — 49,912 4,217 3,380 4,964,465 Total loans $ 23,147,814 324,593 387,117 19,337 3,521 23,882,382 (6 ) (1) Includes $224.5 million and $256.6 million of Substandard accruing loans at September 30, 2017 and December 31, 2016 , respectively. (2) The loans within this risk grade are on non-accrual status. Commercial loans generally have an allowance for loan losses in accordance with ASC 310, and retail loans generally have an allowance for loan losses equal to 50% of the loan amount. (3) The loans within this risk grade are on non-accrual status and have an allowance for loan losses equal to the full loan amount. (4) Represent amounts that were 120 days past due. These credits are downgraded to the Loss category with an allowance for loan losses equal to the full loan amount and are generally charged off upon reaching 181 days past due in accordance with the FFIEC Uniform Retail Credit Classification and Account Management Policy. (5) Total before net deferred fees and costs of $24.3 million . (6) Total before net deferred fees and costs of $26.0 million . The following table details the changes in the allowance for loan losses by loan segment for the nine and three months ended September 30, 2017 . Allowance for Loan Losses and Recorded Investment in Loans As Of and For The Nine Months Ended September 30, 2017 (in thousands) Commercial Real Estate Commercial & Industrial Retail Total Allowance for loan losses: Beginning balance $ 81,816 125,778 44,164 251,758 Charge-offs (11,336 ) (41,390 ) (24,023 ) (76,749 ) Recoveries 6,191 5,181 4,682 16,054 Provision for loan losses 1,289 36,934 20,397 58,620 Ending balance (1) $ 77,960 126,503 45,220 249,683 Ending balance: individually evaluated for impairment 4,108 7,360 783 12,251 Ending balance: collectively evaluated for impairment $ 73,852 119,143 44,437 237,432 Loans: Ending balance: total loans (1)(2) $ 7,226,924 11,727,142 5,557,572 24,511,638 Ending balance: individually evaluated for impairment 64,909 109,434 30,132 204,475 Ending balance: collectively evaluated for impairment $ 7,162,015 11,617,708 5,527,440 24,307,163 As Of and For The Nine Months Ended September 30, 2016 (in thousands) Commercial Real Estate Commercial & Industrial Retail Total Allowance for loan losses: Beginning balance $ 87,133 122,989 42,374 252,496 Charge-offs (13,361 ) (17,098 ) (10,611 ) (41,070 ) Recoveries 10,927 6,122 3,601 20,650 Provision for loan losses (3,597 ) 18,875 6,463 21,741 Ending balance (1) $ 81,102 130,888 41,827 253,817 Ending balance: individually evaluated for impairment 11,066 11,474 1,724 24,264 Ending balance: collectively evaluated for impairment $ 70,036 119,414 40,103 229,553 Loans: Ending balance: total loans (1)(3) $7,472,551 11,009,021 4,807,511 23,289,083 Ending balance: individually evaluated for impairment 102,837 118,442 37,820 259,099 Ending balance: collectively evaluated for impairment $ 7,369,714 10,890,579 4,769,691 23,029,984 (1) As of and for the nine months ended September 30, 2017 and 2016 , there were no purchased credit-impaired loans and no allowance for loan losses for purchased credit-impaired loans. (2) Total before net deferred fees and costs of $24.3 million . (3) Total before net deferred fees and costs of $26.2 million . Allowance for Loan Losses and Recorded Investment in Loans As Of and For The Three Months Ended September 30, 2017 (in thousands) Commercial Real Estate Commercial & Industrial Consumer Total Allowance for loan losses: Beginning balance $ 77,527 123,437 47,131 248,095 Charge-offs (8,129 ) (21,855 ) (14,367 ) (44,351 ) Recoveries 2,543 1,899 1,811 6,253 Provision for loan losses 6,019 23,022 10,645 39,686 Ending balance (1) $ 77,960 126,503 45,220 249,683 Ending balance: individually evaluated for impairment 4,108 7,360 783 12,251 Ending balance: collectively evaluated for impairment $ 73,852 119,143 44,437 237,432 Loans: Ending balance: total loans (1)(2) $ 7,226,924 11,727,142 5,557,572 24,511,638 Ending balance: individually evaluated for impairment 64,909 109,434 30,132 204,475 Ending balance: collectively evaluated for impairment $ 7,162,015 11,617,708 5,527,440 24,307,163 As Of and For The Three Months Ended September 30, 2016 (in thousands) Commercial Real Estate Commercial & Industrial Consumer Total Allowance for loan losses: Beginning balance $ 79,359 129,633 46,084 255,076 Charge-offs (4,084 ) (6,437 ) (3,463 ) (13,984 ) Recoveries 4,237 1,780 1,037 7,054 Provision for loan losses 1,590 5,912 (1,831 ) 5,671 Ending balance (1) $ 81,102 130,888 41,827 253,817 Ending balance: individually evaluated for impairment 11,066 11,474 1,724 24,264 Ending balance: collectively evaluated for impairment $ 70,036 119,414 40,103 229,553 Loans: Ending balance: total loans (1)(3) $ 7,472,551 11,009,021 4,807,511 23,289,083 Ending balance: individually evaluated for impairment 102,837 118,442 37,820 259,099 Ending balance: collectively evaluated for impairment $ 7,369,714 10,890,579 4,769,691 23,029,984 (1 ) As of and for the three months ended September 30, 2017 and 2016 , there were no purchased credit-impaired loans and no allowance for loan losses for purchased credit-impaired loans. (2) Total before net deferred fees and costs of $24.3 million . (3) Total before net deferred fees and costs of $26.2 million . The tables below summarize impaired loans (including accruing TDRs) as of September 30, 2017 and December 31, 2016 . Impaired Loans (including accruing TDRs) September 30, 2017 Nine Months Ended September 30, 2017 Three Months Ended September 30, 2017 (in thousands) Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized With no related allowance recorded Investment properties $ — — — 164 — — — 1-4 family properties 253 2,582 — 374 — 253 — Land and development 1,488 3,172 — 2,084 — 1,911 — Total commercial real estate 1,741 5,754 — 2,622 — 2,164 — Commercial, financial and agricultural 20,696 22,122 — 23,094 — 25,583 — Owner-occupied 97 744 — 8,875 — 7,164 — Total commercial and industrial 20,793 22,866 — 31,969 — 32,747 — Home equity lines 1,072 1,072 — 1,063 — 1,069 — Consumer mortgages — — — 661 — 496 — Credit cards — — — — — — — Other consumer loans — — — — — — — Total consumer 1,072 1,072 — 1,724 — 1,565 — Total impaired loans with no related allowance recorded $ 23,606 29,692 — 36,315 — 36,476 — With allowance recorded Investment properties $ 28,651 28,651 1,116 29,325 903 28,826 306 1-4 family properties 15,741 15,741 452 16,552 664 15,665 278 Land and development 18,776 18,832 2,540 24,825 347 18,544 48 Total commercial real estate 63,168 63,224 4,108 70,702 1,914 63,035 632 Commercial, financial and agricultural 51,819 52,019 5,730 48,694 1,175 53,040 388 Owner-occupied 36,822 36,855 1,630 41,627 1,002 37,004 328 Total commercial and industrial 88,641 88,874 7,360 90,321 2,177 90,044 716 Home equity lines 5,995 5,995 119 7,807 265 6,534 82 Consumer mortgages 18,336 18,336 382 19,270 687 18,369 222 Credit cards — — — — — — — Other consumer loans 4,729 4,729 282 4,507 191 4,224 59 Total consumer 29,060 29,060 783 31,584 1,143 29,127 363 Total impaired loans with allowance recorded $ 180,869 181,158 12,251 192,607 5,234 182,206 1,711 Total impaired loans Investment properties $ 28,651 28,651 1,116 29,489 903 28,826 306 1-4 family properties 15,994 18,323 452 16,926 664 15,918 278 Land and development 20,264 22,004 2,540 26,909 347 20,455 48 Total commercial real estate 64,909 68,978 4,108 73,324 1,914 65,199 632 Commercial, financial and agricultural 72,515 74,141 5,730 71,788 1,175 78,623 388 Owner-occupied 36,919 37,599 1,630 50,502 1,002 44,168 328 Total commercial and industrial 109,434 111,740 7,360 122,290 2,177 122,791 716 Home equity lines 7,067 7,067 119 8,870 265 7,603 82 Consumer mortgages 18,336 18,336 382 19,931 687 18,865 222 Credit cards — — — — — — — Other consumer loans 4,729 4,729 282 4,507 191 4,224 59 Total consumer 30,132 30,132 783 33,308 1,143 30,692 363 Total impaired loans $ 204,475 210,850 12,251 228,922 5,234 218,682 1,711 Impaired Loans (including accruing TDRs) December 31, 2016 Year Ended December 31, 2016 (in thousands) Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized With no related allowance recorded Investment properties $ 748 793 — 2,013 — 1-4 family properties 643 2,939 — 1,021 — Land and development 2,099 7,243 — 6,769 — Total commercial real estate 3,490 10,975 — 9,803 — Commercial, financial and agricultural 17,958 20,577 — 6,321 — Owner-occupied 5,508 7,377 — 8,394 — Total commercial and industrial 23,466 27,954 — 14,715 — Home equity lines 1,051 1,051 — 1,045 — Consumer mortgages 744 814 — 870 — Credit cards — — — — — Other consumer loans — — — — — Total consumer 1,795 1,865 — 1,915 — Total impaired loans with no related allowance recorded $ 28,751 40,794 — 26,433 — With allowance recorded Investment properties $ 31,489 31,489 2,044 42,659 1,436 1-4 family properties 23,642 23,649 769 39,864 855 Land and development 32,789 32,788 5,103 25,568 995 Total commercial real estate 87,920 87,926 7,916 108,091 3,286 Commercial, financial and agricultural 43,386 45,913 5,687 51,968 1,215 Owner-occupied 53,708 53,942 2,697 52,300 1,946 Total commercial and industrial 97,094 99,855 8,384 104,268 3,161 Home equity lines 9,638 9,638 971 9,668 432 Consumer mortgages 20,953 20,953 673 20,993 1,014 Credit cards — — — — — Other consumer loans 5,140 5,140 167 5,062 303 Total consumer 35,731 35,731 1,811 35,723 1,749 Total impaired loans with allowance recorded $ 220,745 223,512 18,111 248,082 8,196 Total impaired loans Investment properties $ 32,237 32,282 2,044 44,672 1,436 1-4 family properties 24,285 26,588 769 40,885 855 Land and development 34,888 40,031 5,103 32,337 995 Total commercial real estate 91,410 98,901 7,916 117,894 3,286 Commercial, financial and agricultural 61,344 66,490 5,687 58,289 1,215 Owner-occupied 59,216 61,319 2,697 60,694 1,946 Total commercial and industrial 120,560 127,809 8,384 118,983 3,161 Home equity lines 10,689 10,689 971 10,713 432 Consumer mortgages 21,697 21,767 673 21,863 1,014 Credit cards — — — — — Other consumer loans 5,140 5,140 167 5,062 303 Total consumer 37,526 37,596 1,811 37,638 1,749 Total impaired loans $ 249,496 264,306 18,111 274,515 8,196 The average recorded investment in impaired loans was $281.2 million and $263.0 million , respectively, for the nine and three months ended September 30, 2016 . Excluding accruing TDRs, there was no interest income recognized for the investment in impaired loans for the nine and three months ended September 30, 2016 . Interest income recognized for accruing TDRs was $6.1 million and $2.1 million , respectively, for the nine and three months ended September 30, 2016 . At September 30, 2017 and December 31, 2016 , impaired loans of $37.6 million and $53.7 million , respectively, were on non-accrual status. Concessions provided in a TDR are primarily in the form of providing a below market interest rate given the borrower's credit risk, a period of time generally less than one year with a reduction of required principal and/or interest payments (e.g., interest only for a period of time), or an extension of the maturity of the loan generally for less than one year. Insignificant periods of reduction of principal and/or interest payments, or one-time deferrals of 3 months or less, are generally not considered to be financial concessions. The following tables represent, by concession type, the post-modification balance for loans modified or renewed during the nine and three months ended September 30, 2017 and 2016 that were reported as accruing or non-accruing TDRs. TDRs by Concession Type Nine Months Ended September 30, 2017 (in thousands, except contract data) Number of Contracts Principal Forgiveness Below Market Interest Rate Term Extensions and/or Other Concessions Total Investment properties — $ — — — — 1-4 family properties 21 — 2,090 1,477 3,567 Land acquisition 4 — 157 895 1,052 Total commercial real estate 25 — 2,247 2,372 4,619 Commercial, financial and agricultural 50 — 8,703 12,145 20,848 Owner-occupied 4 — 35 1,705 1,740 Total commercial and industrial 54 — 8,738 13,850 22,588 Home equity lines — — — — — Consumer mortgages 8 — 248 1,190 1,438 Credit cards — — — — — Other retail loans 25 — 682 958 1,640 Total retail 33 — 930 2,148 3,078 Total TDRs 112 $ — 11,915 18,370 30,285 (1 ) Three Months Ended September 30, 2017 (in thousands, except contract data) Number of Contracts Principal Forgiveness Below Market Interest Rate Term Extensions and/or Other Concessions Total Investment properties — $ — — — — 1-4 family properties 5 — — 964 964 Land and development 3 — 157 760 917 Total commercial real estate 8 — 157 1,724 1,881 Commercial, financial and agricultural 22 — 2,943 5,866 8,809 Owner-occupied 3 — 35 1,683 1,718 Total commercial and industrial 25 — 2,978 7,549 10,527 Home equity lines — — — — — Consumer mortgages 7 — 248 1,181 1,429 Credit cards — — — — — Other consumer loans 17 — 682 388 1,070 Total consumer 24 — 930 1,569 2,499 Total TDRs 57 $ — 4,065 10,842 14,907 (1 ) (1) No net charge-offs were recorded during the nine and three months ended September 30, 2017 upon restructuring of these loans. TDRs by Concession Type Nine Months Ended September 30, 2016 (in thousands, except contract data) Number of Contracts Principal Forgiveness Below Market Interest Rate Term Extensions and/or Other Concessions Total Investment properties 4 $ — 1,826 3,518 5,344 1-4 family properties 23 — 3,703 1,211 4,914 Land acquisition 13 — — 1,766 1,766 Total commercial real estate 40 — 5,529 6,495 12,024 Commercial, financial and agricultural 50 — 13,948 5,232 19,180 Owner-occupied 7 — 5,458 550 6,008 Total commercial and industrial 57 — 19,406 5,782 25,188 Home equity lines 5 — 224 123 347 Consumer mortgages 6 — 354 51 405 Credit cards — — — — — Other retail loans 24 — 394 1,828 2,222 Total retail 35 — 972 2,002 2,974 Total TDRs 132 $ — 25,907 14,279 40,186 (2 ) Three Months Ended September 30, 2016 (in thousands, except contract data) Number of Contracts Principal Forgiveness Below Market Interest Rate Term Extensions and/or Other Concessions Total Investment properties 1 $ — — 3,370 3,370 1-4 family properties 4 — 213 47 260 Land and development 2 — — 497 497 Total commercial real estate 7 — 213 3,914 4,127 Commercial, financial and agricultural 5 — — 387 387 Owner-occupied 1 — 2,791 — 2,791 Total commercial and industrial 6 — 2,791 387 3,178 Home equity lines 2 — — 123 123 Consumer mortgages — — — — — Credit cards — — — — — Other consumer loans 7 — 70 294 364 Total consumer 9 — 70 417 487 Total TDRs 22 $ — 3,074 4,718 7,792 (2 ) (2) No net charge-offs were recorded during the nine and three months ended September 30, 2016 upon restructuring of these loans. For the nine and three months ended September 30, 2017 , there were four defaults with a recorded investment of $498 thousand and one default with a recorded investment of $206 thousand , respectively, on accruing TDRs restructured during the previous twelve months (defaults are defined as the earlier of the TDR being placed on non-accrual status or reaching 90 days past due with respect to principal and/or interest payments) compared to two defaults with a recorded investment of $181 thousand and one default with a recorded investment of $89 thousand , respectively, for the nine and three months ended September 30, 2016 . If, at the time a loan was designated as a TDR, the loan was not already impaired, the measurement of impairment that resulted from the TDR designation closely approximates the reserve derived through specific loan measurement of impairment in accordance with ASC 310-10-35. Generally, the change in the allowance for loan losses resulting from such TDR designation is not significant. At September 30, 2017 , the allowance for loan losses allocated to accruing TDRs totaling $166.9 million was $8.5 million compared to accruing TDRs of $195.8 million with an allocated allowance for loan losses of $9.8 million at December 31, 2016 . Non-accrual, non-homogeneous loans (commercial-type impaired loans greater than $1 million ) that are designated as TDRs are individually measured for the amount of impairment, if any, both before and after the TDR designation .

Other Comprehensive Income (Los

Other Comprehensive Income (Loss)	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Other Comprehensive Income (Loss)	Note 7 - Other Comprehensive Income (Loss) The following tables illustrate activity within the balances in accumulated other comprehensive income (loss) by component for the nine and three months ended September 30, 2017 and 2016 . Changes in Accumulated Other Comprehensive Income (Loss) by Component (Net of Income Taxes) (in thousands) Net unrealized gains (losses) on cash flow hedges Net unrealized gains (losses) on investment securities available for sale Post-retirement unfunded health benefit Total Balance at December 31, 2016 $ (12,217 ) (44,324 ) 882 (55,659 ) Other comprehensive income before reclassifications — 15,812 38 15,850 Amounts reclassified from accumulated other comprehensive income (loss) 80 178 (45 ) 213 Net current period other comprehensive income 80 15,990 (7 ) 16,063 Balance as of September 30, 2017 $ (12,137 ) (28,334 ) 875 (39,596 ) Balance as of July 1, 2017 $ (12,137 ) (36,586 ) 858 (47,865 ) Other comprehensive income before reclassifications — 3,359 38 3,397 Amounts reclassified from accumulated other comprehensive income (loss) — 4,893 (21 ) 4,872 Net current period other comprehensive income — 8,252 17 8,269 Balance as of September 30, 2017 $ (12,137 ) (28,334 ) 875 (39,596 ) Changes in Accumulated Other Comprehensive Income (Loss) by Component (Net of Income Taxes) (in thousands) Net unrealized gains (losses) on cash flow hedges Net unrealized gains (losses) on investment securities available for sale Post-retirement unfunded health benefit Total Balance at December 31, 2015 $ (12,504 ) (18,222 ) 907 (29,819 ) Other comprehensive income before reclassifications — 34,827 63 34,890 Amounts reclassified from accumulated other comprehensive income (loss) 247 (77 ) (76 ) 94 Net current period other comprehensive income 247 34,750 (13 ) 34,984 Balance as of September 30, 2016 $ (12,257 ) 16,528 894 5,165 Balance as of July 1, 2016 $ (12,297 ) 22,459 843 11,005 Other comprehensive income (loss) before reclassifications — (5,895 ) 63 (5,832 ) Amounts reclassified from accumulated other comprehensive income (loss) 40 (36 ) (12 ) (8 ) Net current period other comprehensive income (loss) 40 (5,931 ) 51 (5,840 ) Balance as of September 30, 2016 $ (12,257 ) 16,528 894 5,165 In accordance with ASC 740-20-45-11(b), a deferred tax asset valuation allowance associated with unrealized gains and losses not recognized in income is charged directly to other comprehensive income (loss). During the years 2010 and 2011, Synovus recorded a deferred tax asset valuation allowance associated with unrealized gains and losses not recognized in income directly to other comprehensive income (loss) by applying the portfolio approach for allocation of the valuation allowance. Synovus has consistently applied the portfolio approach which treats derivative financial instruments, equity securities, and debt securities as a single portfolio. As of September 30, 2017 , the balance in net unrealized gains (losses) on cash flow hedges and net unrealized gains (losses) on investment securities available for sale includes unrealized losses of $12.1 million and $13.3 million , respectively, related to the residual tax effects remaining in OCI due to a previously established deferred tax asset valuation allowance. Under the portfolio approach, these unrealized losses are realized at the time the entire portfolio is sold or disposed. Reclassifications out of Accumulated Other Comprehensive Income (Loss) Details About Accumulated Other Comprehensive Income (Loss) Components Amount Reclassified from Accumulated Other Comprehensive Income (Loss) Affected Line Item in the Statement Where Net Income is Presented For the Nine Months Ended September 30, 2017 2016 Net unrealized gains (losses) on cash flow hedges: Amortization of deferred losses $ (130 ) (205 ) Interest expense Amortization of deferred losses — (197 ) Loss on early extinguishment of debt, net 50 155 Income tax (expense) benefit $ (80 ) (247 ) Reclassifications, net of income taxes Net unrealized (losses) gains on investment securities available for sale: Realized (losses) gains on sale of securities $ (289 ) 126 Investment securities (losses) gains, net 111 (49 ) Income tax (expense) benefit $ (178 ) 77 Reclassifications, net of income taxes Post-retirement unfunded health benefit: Amortization of actuarial gains $ 74 124 Salaries and other personnel expense (29 ) (48 ) Income tax (expense) benefit $ 45 76 Reclassifications, net of income taxes Reclassifications out of Accumulated Other Comprehensive Income (Loss) Details About Accumulated Other Comprehensive Income (Loss) Components Amount Reclassified from Accumulated Other Comprehensive Income (Loss) Affected Line Item in the Statement Where Net Income is Presented For the Three Months Ended September 30, 2017 2016 Net unrealized gains (losses) on cash flow hedges: Amortization of deferred losses $ — (65 ) Interest expense — 25 Income tax (expense) benefit $ — (40 ) Reclassifications, net of income taxes Net unrealized gains on investment securities available for sale: Realized net (loss)gain on sale of securities $ (7,956 ) 59 Investment securities (losses) gains, net 3,063 (23 ) Income tax (expense) benefit $ (4,893 ) 36 Reclassifications, net of income taxes Post-retirement unfunded health benefit: Amortization of actuarial gains $ 34 20 Salaries and other personnel expense (13 ) (8 ) Income tax (expense) benefit $ 21 12 Reclassifications, net of income taxes

Fair Value Accounting

Fair Value Accounting	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value Accounting	Note 8 - Fair Value Accounting Synovus carries various assets and liabilities at fair value based on the fair value accounting guidance under ASC 820, Fair Value Measurements , and ASC 825, Financial Instruments . Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an “exit price”) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Fair Value Hierarchy Synovus determines the fair value of its financial instruments based on the fair value hierarchy established under ASC 820-10, which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. A financial instrument’s categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the financial instrument's fair value measurement in its entirety. There are three levels of inputs that may be used to measure fair value. The three levels of inputs of the valuation hierarchy are defined below: Level 1 Quoted prices (unadjusted) in active markets for identical assets and liabilities for the instrument or security to be valued. Level 1 assets include marketable equity securities, U.S. Treasury securities, and mutual funds. Level 2 Observable inputs other than Level 1 quoted prices, such as quoted prices for similar assets and liabilities in active markets, quoted prices in markets that are not active or model-based valuation techniques for which all significant assumptions are derived principally from or corroborated by observable market data. Level 2 assets and liabilities include debt securities with quoted prices that are traded less frequently than exchange-traded instruments and derivative contracts whose value is determined by using a pricing model with inputs that are observable in the market or can be derived principally from or corroborated by observable market data. U.S. Government sponsored agency securities, mortgage-backed securities issued by U.S. Government sponsored enterprises and agencies, obligations of states and municipalities, collateralized mortgage obligations issued by U.S. Government sponsored enterprises, and mortgage loans held-for-sale are generally included in this category. Level 3 Unobservable inputs that are supported by little, if any, market activity for the asset or liability. Level 3 assets and liabilities include financial instruments whose value is determined using pricing models, discounted cash flow models and similar techniques, and may also include the use of market prices of assets or liabilities that are not directly comparable to the subject asset or liability. These methods of valuation may result in a significant portion of the fair value being derived from unobservable assumptions that reflect Synovus' own estimates for assumptions that market participants would use in pricing the asset or liability. This category primarily includes collateral-dependent impaired loans, other real estate, certain equity investments, private equity investments, GGL/SBA loan servicing assets, and contingent consideration. See "Part II - Item 8. Financial Statements and Supplementary Data - Note 16 - Fair Value Accounting" to the consolidated financial statements of Synovus' 2016 Form 10-K 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 on a Recurring Basis The following table presents all financial instruments measured at fair value on a recurring basis as of September 30, 2017 and December 31, 2016 , according to the valuation hierarchy included in ASC 820-10. For equity and debt securities, class was determined based on the nature and risks of the investments. Synovus did not have any transfers between levels during the nine and three months ended September 30, 2017 and year ended December 31, 2016 . September 30, 2017 (in thousands) Level 1 Level 2 Level 3 Total Assets and Liabilities at Fair Value Assets Trading securities: Mortgage-backed securities issued by U.S. Government sponsored enterprises — 494 — 494 Collateralized mortgage obligations issued by U.S. Government sponsored enterprises — 10,484 — 10,484 State and municipal securities — 1,101 — 1,101 Other investments — 250 — 250 Total trading securities $ — 12,329 — 12,329 Mortgage loans held for sale — 54,072 — 54,072 Investment securities available for sale: U.S. Treasury securities 83,181 — — 83,181 U.S. Government agency securities — 11,038 — 11,038 Mortgage-backed securities issued by U.S. Government agencies — 127,384 — 127,384 Mortgage-backed securities issued by U.S. Government sponsored enterprises — 2,651,852 — 2,651,852 Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises — 931,440 — 931,440 State and municipal securities — 181 — 181 Corporate debt and other securities (1) 3,162 15,287 1,918 20,367 Total investment securities available for sale $ 86,343 3,737,182 1,918 3,825,443 Private equity investments — — 15,671 15,671 Mutual funds held in rabbi trusts 13,439 — — 13,439 GGL/SBA loans servicing asset — — 4,270 4,270 Derivative assets: Interest rate contracts — 14,896 — 14,896 Mortgage derivatives (2) — 974 — 974 Total derivative assets $ — 15,870 — 15,870 Liabilities Trading account liabilities — 7,860 — 7,860 Earnout liability (3) — — 16,000 16,000 Derivative liabilities: Interest rate contracts — 12,369 — 12,369 Mortgage derivatives (2) — 32 — 32 Visa derivative — — 4,693 4,693 Total derivative liabilities $ — 12,401 4,693 17,094 December 31, 2016 (in thousands) Level 1 Level 2 Level 3 Total Assets and Liabilities at Fair Value Assets Trading securities: Mortgage-backed securities issued by U.S. Government agencies — 3,460 — 3,460 Collateralized mortgage obligations issued by U.S. Government sponsored enterprises — 3,438 — 3,438 State and municipal securities — 426 — 426 Other investments 1,890 100 — 1,990 Total trading securities $ 1,890 7,424 — 9,314 Mortgage loans held for sale — 51,545 — 51,545 Investment securities available for sale: U.S. Treasury securities 107,802 — — 107,802 U.S. Government agency securities — 12,993 — 12,993 Mortgage-backed securities issued by U.S. Government agencies — 174,202 — 174,202 Mortgage-backed securities issued by U.S. Government sponsored enterprises — 2,506,340 — 2,506,340 Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises — 890,442 — 890,442 State and municipal securities — 2,794 — 2,794 Equity securities 3,782 — — 3,782 Corporate debt and other securities (1) 3,092 14,952 1,796 19,840 Total investment securities available for sale $ 114,676 3,601,723 1,796 3,718,195 Private equity investments — — 25,493 25,493 Mutual funds held in rabbi trusts 11,479 — — 11,479 Derivative assets: Interest rate contracts — 17,157 — 17,157 Mortgage derivatives (2) — 3,466 — 3,466 Total derivative assets $ — 20,623 — 20,623 Liabilities Earnout liability (3) — — 14,000 14,000 Derivative liabilities: Interest rate contracts — 17,531 — 17,531 Visa derivative — — 5,768 5,768 Total derivative liabilities $ — 17,531 5,768 23,299 (1) Based on an analysis of the nature and risks of these investments, Synovus has determined that presenting these investments as a single asset class is appropriate. (2) Mortgage derivatives consist of customer interest rate lock commitments that relate to the potential origination of mortgage loans, which would be classified as held for sale and forward loan sales commitments with third-party investors. (3) Earnout liability consists of contingent consideration obligation related to the Global One acquisition. Fair Value Option The following table summarizes the difference between the fair value and the unpaid principal balance of mortgage loans held for sale measured at fair value and the changes in fair value of these loans. Mortgage loans held for sale are initially measured at fair value with subsequent changes in fair value recognized in earnings. Changes in fair value are recorded as a component of mortgage banking income in the Consolidated Statements of Income. An immaterial portion of these changes in fair value was attributable to changes in instrument-specific credit risk. Changes in Fair Value Included in Net Income For the Nine Months Ended September 30, For the Three Months Ended September 30, (in thousands) 2017 2016 2017 2016 Mortgage loans held for sale $ 850 1,762 $ (104 ) (87 ) Mortgage Loans Held for Sale (in thousands) As of September 30, 2017 As of December 31, 2016 Fair value $ 54,072 51,545 Unpaid principal balance 52,791 51,114 Fair value less aggregate unpaid principal balance $ 1,281 431 Changes in Level 3 Fair Value Measurements and Quantitative Information about Level 3 Fair Value Measurements As noted above, Synovus uses significant unobservable inputs in determining the fair value of assets and liabilities classified as Level 3 in the fair value hierarchy. The table below includes a roll-forward of the amounts on the Consolidated Balance Sheets for the nine and three months ended September 30, 2017 and 2016 (including the change in fair value), for financial instruments of a material nature that are classified by Synovus within Level 3 of the fair value hierarchy and are measured at fair value on a recurring basis. Transfers between fair value levels are recognized at the end of the reporting period in which the associated changes in inputs occur. During the nine and three months ended September 30, 2017 and 2016 , Synovus did not have any transfers between levels in the fair value hierarchy. Nine Months Ended September 30, 2017 (in thousands) Investment Securities Available for Sale Private Equity Investments Visa Derivative Earnout Liability (1) GGL / SBA Loans Servicing Asset (2) Beginning balance, January 1, $ 1,796 25,493 (5,768 ) (14,000 ) — Total (losses) gains realized/unrealized: Included in earnings — (3,193 ) — (3,766 ) (721 ) Unrealized gains (losses) included in other comprehensive income 122 — — — — Additions — — — — 539 Sales and settlements — (6,629 ) 1,075 — — Transfer from amortization method to fair value — — — — 4,452 Measurement period adjustments related to Global One acquisition — — — 1,766 — Ending balance, September 30, $ 1,918 15,671 (4,693 ) (16,000 ) 4,270 Total net (losses) gains for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets/liabilities still held at September 30, $ — (3,193 ) — (3,766 ) (721 ) Three Months Ended September 30, 2017 (in thousands) Investment Securities Available for Sale Private Equity Investments Visa Derivative Earnout Liability (1) GGL / SBA Loans Servicing Asset (2) Beginning balance, July 1, $ 1,927 15,698 (5,053 ) (13,941 ) 4,297 Total (losses) gains realized/unrealized: Included in earnings — (27 ) — (2,059 ) (27 ) Unrealized gains (losses) included in other comprehensive income (9 ) — — — — Additions — — — — — Sales and settlements — — 360 — — Measurement period adjustments related to Global One acquisition — — — — — Ending balance, September 30, $ 1,918 15,671 (4,693 ) (16,000 ) 4,270 Total net (losses) gains for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets/liabilities still held at September 30, $ — (27 ) — (2,059 ) (27 ) (1) Earnout liability consists of contingent consideration obligation related to the Global One acquisition. (2) Effective January 1, 2017, Synovus elected the fair value option for determining the value of the GGL/SBA loans servicing asset. Synovus has retained servicing responsibilities on sold GGL/SBA loans and receives a servicing fee. The servicing asset is established at fair value at the time of the sale based on an analysis of future cash flows that incorporates estimates for discount rates, prepayment speeds, and delinquency rates. The servicing asset is measured at fair value on a quarterly basis with changes in fair value included with the associated servicing fee in other non-interest income. Prior to 2017, Synovus accounted for the GGL/SBA loans servicing asset using the amortization method. Nine Months Ended September 30, 2016 (in thousands) Investment Securities Available for Sale Private Equity Investments Visa Derivative Beginning balance, January 1, $ 1,745 27,148 (1,415 ) Total (losses) gains realized/unrealized: Included in earnings — (527 ) (1,080 ) Unrealized gains (losses) included in other comprehensive income 28 — — Settlements — (629 ) 1,080 Ending balance, September 30, $ 1,773 25,992 (1,415 ) Total net (losses) gains for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets still held at September 30, $ — (527 ) (1,080 ) Three Months Ended September 30, 2016 (in thousands) Investment Securities Available for Sale Private Equity Investments Visa Derivative Beginning balance, July 1, $ 1,625 26,866 (1,415 ) Total (losses) gains realized/unrealized: Included in earnings — (249 ) (360 ) Unrealized gains (losses) included in other comprehensive income 148 — — Settlements — (625 ) 360 Ending balance, September 30, $ 1,773 25,992 (1,415 ) Total net (losses) gains for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets still held at September 30, $ — (249 ) (360 ) The table below provides an overview of the valuation techniques and significant unobservable inputs used in those techniques to measure financial instruments that are classified within Level 3 of the valuation hierarchy and are measured at fair value on a recurring basis. September 30, 2017 December 31, 2016 Valuation Technique Significant Unobservable Input Range/Weighted Average Range/Weighted Average Assets and liabilities measured at fair value on a recurring basis Investment Securities Available for Sale - Other Investments: Trust preferred securities Discounted cash flow analysis Credit spread embedded in discount rate 398 bps 442 bps Private equity investments Individual analysis of each investee company Multiple factors, including but not limited to, current operations, financial condition, cash flows, evaluation of business management and financial plans, and recently executed financing transactions related to the investee companies N/A N/A Discount for lack of liquidity (1) N/A 15% GGL/SBA loans servicing asset Discounted cash flow analysis Discount rate Prepayment speeds 12.19% 6.75% N/A Earnout liability Option pricing methods and Monte Carlo simulation Global One Earnout, as defined in merger agreement, for the five years ending October 1, 2021 $11.8 million - $16.7 million $9.3 million - $14.2 million Visa derivative liability Discounted cash flow analysis Estimated timing of resolution of covered litigation, future cumulative deposits to the litigation escrow for settlement of the covered litigation, and estimated future monthly fees payable to the derivative counterparty 1-5 years 1-5 years (1) Represents management's estimate of discount that market participants would require based on the instrument's lack of liquidity. Assets Measured at Fair Value on a Non-recurring Basis Certain assets are 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. The following table presents assets measured at fair value on a non-recurring basis as of the dates indicated for which there was a fair value adjustment during the period. September 30, 2017 December 31, 2016 (in thousands) Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Impaired loans * $ — — 3,114 3,114 — — 21,742 21,742 Other loans held for sale — — 31,253 31,253 — — — — Other real estate — — 8,137 8,137 — — 19,305 19,305 Other assets held for sale — — 4,033 4,033 — — 12,083 12,083 * Collateral-dependent impaired loans that were written down to fair value during the period. The following table presents fair value adjustments recognized in earnings for the nine and three months ended September 30, 2017 and 2016 for the assets measured at fair value on a non-recurring basis. Nine Months Ended September 30, Three Months Ended September 30, (in thousands) 2017 2016 2017 2016 Impaired loans * $ 1,075 1,329 $ 83 59 Other loans held for sale 25,051 2,096 25,051 2,096 Other real estate 5,165 2,405 5,165 968 Other assets held for sale 1,683 7,532 1,683 907 * Collateral-dependent impaired loans that were written down to fair value during the period. The table below provides an overview of the valuation techniques and significant unobservable inputs used in those techniques to measure financial instruments that are classified within Level 3 of the valuation hierarchy and are measured at fair value on a non-recurring basis. The range of sensitivities that management utilized in its fair value calculations is deemed acceptable in the industry with respect to the identified financial instruments. September 30, 2017 December 31, 2016 Valuation Technique Significant Unobservable Input Range (Weighted Average) (1) Range (Weighted Average) (1) Assets measured at fair value on a non-recurring basis Collateral dependent impaired loans Third-party appraised value of collateral less estimated selling costs Discount to appraised value (2) Estimated selling costs 0% - 60% (43%) 0% - 10% (7%) 0%-52% (25%) 0%-10% (7%) Other loans held for sale Third-party appraised value of collateral less estimated selling costs Discount to appraised value (2) Estimated selling costs 0% - 85% (48%) 0% - 10% (2%) N/A Other real estate Third-party appraised value of real estate less estimated selling costs Discount to appraised value (2) Estimated selling costs 0% - 86% (32%) 0% - 10% (7%) 0%-10% (5%) 0%-10% (7%) Other assets held for sale Third-party appraised value less estimated selling costs or BOV Discount to appraised value (2) Estimated selling costs 15%-46% (22%) 0%-10% (7%) 0%-81% (47%) 0%-10% (7%) (1) The range represents management's estimate of the high and low of the value that would be assigned to a particular input. For assets measured at fair value on a non-recurring basis, the weighted average is the measure of central tendencies; it is not the value that management is using for the asset or liability. (2) Synovus also makes adjustments to the values of the assets listed above for reasons including age of the appraisal, information known by management about the property, such as occupancy rates, changes to the physical condition of the property, and other factors. 3Q17 included certain balance sheet restructuring actions which included discounts to fair value for planned accelerated dispositions of other loans held for sale, other real estate, and other assets held for sale. Fair Value of Financial Instruments The following table presents the carrying and fair values of financial instruments at September 30, 2017 and December 31, 2016 . The fair values represent management’s estimates based on various methodologies and assumptions. For financial instruments that are not recorded at fair value on the balance sheet, such as loans held for investment, interest bearing deposits (including brokered deposits), and long-term debt, the fair value amounts should not be taken as an estimate of the amount that would be realized if all such financial instruments were to be settled immediately. The carrying and estimated fair values of financial instruments, as well as the level within the fair value hierarchy, as of September 30, 2017 and December 31, 2016 are as follows: September 30, 2017 (in thousands) Carrying Value Fair Value Level 1 Level 2 Level 3 Financial assets Cash and cash equivalents $ 386,459 386,459 386,459 — — Interest bearing funds with Federal Reserve Bank 1,297,581 1,297,581 1,297,581 — — Interest earning deposits with banks 6,047 6,047 6,047 — — Federal funds sold and securities purchased under resale agreements 48,820 48,820 48,820 — — Trading account assets 12,329 12,329 — 12,329 — Mortgage loans held for sale 54,072 54,072 — 54,072 — Other loans held for sale 31,253 31,253 — — 31,253 Investment securities available for sale 3,825,443 3,825,443 86,343 3,737,182 1,918 Private equity investments 15,671 15,671 — — 15,671 Mutual funds held in rabbi trusts 13,439 13,439 13,439 — — Loans, net of deferred fees and costs 24,487,360 24,193,343 — — 24,193,343 GGL/SBA loans servicing asset 4,270 4,270 — — 4,270 Derivative assets 15,870 15,870 — 15,870 — Financial liabilities Trading account liabilities 7,860 7,860 7,860 Non-interest bearing deposits 7,302,682 7,302,682 — 7,302,682 — Interest bearing deposits 18,883,546 18,891,446 — 18,891,446 — Federal funds purchased, other short-term borrowings and other short-term liabilities 141,539 141,539 141,539 — — Long-term debt 1,882,607 1,929,043 — 1,929,043 — Other liabilities 16,000 16,000 — — 16,000 Derivative liabilities 17,094 17,094 — 12,401 4,693 December 31, 2016 (in thousands) Carrying Value Fair Value Level 1 Level 2 Level 3 Financial assets Cash and cash equivalents $ 395,175 395,175 395,175 — — Interest bearing funds with Federal Reserve Bank 527,090 527,090 527,090 — — Interest earning deposits with banks 18,720 18,720 18,720 — — Federal funds sold and securities purchased under resale agreements 58,060 58,060 58,060 — — Trading account assets 9,314 9,314 1,890 7,424 — Mortgage loans held for sale 51,545 51,545 — 51,545 — Investment securities available for sale 3,718,195 3,718,195 114,676 3,601,723 1,796 Private equity investments 25,493 25,493 — — 25,493 Mutual funds held in rabbi trusts 11,479 11,479 11,479 — — Loans, net of deferred fees and costs 23,856,391 23,709,434 — — 23,709,434 Derivative assets 20,623 20,623 — 20,623 — Financial liabilities Non-interest bearing deposits 7,085,804 7,085,804 — 7,085,804 — Interest bearing deposits 17,562,256 17,560,021 — 17,560,021 — Federal funds purchased, other short-term borrowings and other short-term liabilities 159,699 159,699 159,699 — — Long-term debt 2,160,881 2,217,544 — 2,217,544 — Other liabilities 14,000 14,000 — — 14,000 Derivative liabilities 23,299 23,299 — 17,531 5,768

Derivative Instruments

Derivative Instruments	9 Months Ended
	Sep. 30, 2017
Summary of Derivative Instruments [Abstract]
Derivative Instruments	Note 9 - Derivative Instruments As part of its overall interest rate risk management activities, Synovus utilizes derivative instruments to manage its exposure to various types of interest rate risk. These derivative instruments generally consist of interest rate swaps, interest rate lock commitments made to prospective mortgage loan customers, and commitments to sell fixed-rate mortgage loans. Interest rate lock commitments represent derivative instruments since it is intended that such loans will be sold. Synovus may also utilize interest rate swaps to manage interest rate risks primarily arising from its core banking activities. These interest rate swap transactions generally involve the exchange of fixed and floating interest rate payment obligations without the exchange of underlying principal amounts. Swaps may be designated as either cash flow hedges or fair value hedges, as discussed below. As of September 30, 2017 and December 31, 2016 , Synovus had no outstanding interest rate swap contracts utilized to manage interest rate risk related to core banking activities. Synovus is party to master netting arrangements with its dealer counterparties; however, Synovus does not offset assets and liabilities under these arrangements for financial statement presentation purposes. Counterparty Credit Risk and Collateral Entering into derivative contracts potentially exposes Synovus to the risk of counterparties’ failure to fulfill their legal obligations, including, but not limited to, potential amounts due or payable under each derivative contract. Notional principal amounts are often used to express the volume of these transactions, but the amounts potentially subject to credit risk are much smaller. Synovus assesses the credit risk of its dealer counterparties by regularly monitoring publicly available credit rating information, evaluating other market indicators, and periodically reviewing detailed financials. Dealer collateral requirements are determined via risk-based policies and procedures and in accordance with existing agreements. Synovus seeks to minimize dealer credit risk by dealing with highly rated counterparties and by obtaining collateral for exposures above certain predetermined limits. Management closely monitors credit conditions within the customer swap portfolio, which management deems to be of higher risk than dealer counterparties. Collateral is secured at origination and credit related fair value adjustments are recorded against the asset value of the derivative as deemed necessary based upon an analysis, which includes consideration of the current asset value of the swap, customer credit rating, collateral value, and customer standing with regards to its swap contractual obligations and other related matters. Such asset values fluctuate based upon changes in interest rates regardless of changes in notional amounts and changes in customer specific risk. Cash Flow Hedges As of September 30, 2017 and December 31, 2016, there were no cash flow hedges outstanding. The unamortized deferred net loss balance from previously terminated cash flow hedges at December 31, 2016 of $(130) thousand was recognized during the nine months ended September 30, 2017 . Fair Value Hedges As of September 30, 2017 and December 31, 2016, there were no fair value hedges outstanding. The unamortized deferred gain balance on all previously terminated fair value hedges at December 31, 2016 of $873 thousand was recognized during the nine months ended September 30, 2017 . Customer Related Derivative Positions Synovus enters into interest rate swap agreements to facilitate the risk management strategies of a small number of commercial banking customers. Synovus mitigates this risk by entering into equal and offsetting interest rate swap agreements with highly rated counterparties. The interest rate swap agreements are free-standing derivatives and are recorded at fair value on Synovus' Consolidated Balance Sheets. Fair value changes are recorded as a component of non-interest income. As of September 30, 2017 , the notional amount of customer related interest rate derivative financial instruments, including both the customer position and the offsetting position, was $1.54 billion , an increase of $216.9 million compared to December 31, 2016 . Visa Derivative In conjunction with the sale of Class B shares of common stock issued by Visa to Synovus as a Visa USA member, Synovus entered into a derivative contract with the purchaser, which provides for settlements between the parties based upon a change in the ratio for conversion of Visa Class B shares to Visa Class A shares. The conversion ratio changes when Visa deposits funds to a litigation escrow established by Visa to pay settlements for certain litigation, for which Visa is indemnified by Visa USA members. The litigation escrow is funded by proceeds from Visa’s conversion of Class B shares. The fair value of the derivative contract was $4.7 million and $5.8 million at September 30, 2017 and December 31, 2016 , respectively. The fair value of the derivative contract is determined based on management's estimate of the timing and amount of the Covered Litigation settlement, and the resulting payments due to the counterparty under the terms of the contract. Management believes that the estimate of Synovus' exposure to the Visa indemnification and fees associated with the Visa derivative is adequate based on current information, including Visa's recent announcements and disclosures. However, future developments in the litigation could require potentially significant changes to Synovus' estimate. See "Part II - Item 8. Financial Statements and Supplementary Data - Note 19 - Visa Shares and Related Agreements" of Synovus' 2016 Form 10-K for further information. Mortgage Derivatives Synovus originates first lien residential mortgage loans for sale into the secondary market. Mortgage loans are sold by Synovus for conversion to securities and the servicing of these loans is generally sold to a third-party servicing aggregator, or Synovus sells the mortgage loans as whole loans to investors either individually or in bulk on a servicing released basis. Synovus enters into interest rate lock commitments for residential mortgage loans which commits it to lend funds to a potential borrower at a specific interest rate and within a specified period of time. Interest rate lock commitments that relate to the origination of mortgage loans that, if originated, will be held for sale, are considered derivative financial instruments under applicable accounting guidance. Outstanding interest rate lock commitments expose Synovus to the risk that the price of the mortgage loans underlying the commitments may decline due to increases in mortgage interest rates from inception of the rate lock to the funding of the loan. At September 30, 2017 and December 31, 2016 , Synovus had commitments to fund at a locked interest rate, primarily fixed-rate mortgage loans to customers in the amount of $ 64.3 million and $88.2 million , respectively. Fair value adjustments related to these commitments resulted in a loss of $595 thousand and a gain of $1.0 million for the nine months ended September 30, 2017 and 2016 , respectively, which was recorded as a component of mortgage banking income in the Consolidated Statements of Income. At September 30, 2017 and December 31, 2016 , outstanding commitments to sell primarily fixed-rate mortgage loans amounted to $83.0 million and $126.5 million , respectively. Such commitments are entered into to reduce the exposure to market risk arising from potential changes in interest rates, which could affect the fair value of mortgage loans held for sale and outstanding rate lock commitments, which guarantee a certain interest rate if the loan is ultimately funded or granted by Synovus as a mortgage loan held for sale. The commitments to sell mortgage loans are at fixed prices and are scheduled to settle at specified dates that generally do not exceed 90 days. Fair value adjustments related to these outstanding commitments to sell mortgage loans resulted in a loss of $1.9 million and $830.0 thousand for the nine months ended September 30, 2017 and 2016 , respectively, which were recorded as a component of mortgage banking income in the Consolidated Statements of Income. Collateral Requirements Pursuant to the Dodd-Frank Act, certain derivative transactions have collateral requirements, both at the inception of the trade and as the value of each derivative position changes. As of September 30, 2017 , collateral totaling $45.8 million of federal funds sold was pledged to the derivative counterparties to comply with collateral requirements. Effective January 3, 2017, the CME amended its rulebook to legally characterize variation margin cash payments for cleared OTC derivatives as settlement rather than as collateral. As a result, in 2017, Synovus began reducing the corresponding derivative asset and liability balances for CME-cleared OTC derivatives to reflect the settlement of those positions via the exchange of variation margin. The impact of derivative instruments on the Consolidated Balance Sheets at September 30, 2017 and December 31, 2016 is presented below. Fair Value of Derivative Assets Fair Value of Derivative Liabilities (in thousands) Location on Consolidated Balance Sheets September 30, 2017 December 31, 2016 Location on Consolidated Balance Sheets September 30, 2017 December 31, 2016 Derivatives not designated as hedging instruments: Interest rate contracts Other assets $ 14,896 17,157 Other liabilities 12,369 17,531 Mortgage derivatives Other assets 974 3,466 Other liabilities 32 — Visa derivative — — Other liabilities 4,693 5,768 Total derivatives not designated as hedging instruments $ 15,870 20,623 17,094 23,299 The pre-tax effect of fair value hedges on the Consolidated Statements of Income for the nine and three months ended September 30, 2017 and 2016 is presented below. Location of Gain (Loss) Recognized in Income Gain (Loss) Recognized in Income (in thousands) Nine Months Ended September 30, Derivatives not designated as hedging instruments 2017 2016 Interest rate contracts (1) Other non-interest income $ (5 ) 39 Mortgage derivatives (2) Mortgage banking income (2,524 ) 189 Total $ (2,529 ) 228 Gain (Loss) Recognized in Income (in thousands) Three Months Ended September 30, Derivatives not designated as hedging instruments Location of Gain (Loss) Recognized in Income 2017 2016 Interest rate contracts (1) Other non-interest income $ (4 ) 5 Mortgage derivatives (2) Mortgage banking income (451 ) 674 Total $ (455 ) 679 (1) Gain (loss) represents net fair value adjustments (including credit related adjustments) for customer swaps and offsetting positions. (2) Gain (loss) represents net fair value adjustments recorded for interest rate lock commitments and commitments to sell mortgage loans to third-party investors. During the nine months ended September 30, 2017 and 2016 , Synovus reclassified $873 thousand and $1.4 million , respectively, from hedge-related basis adjustment, a component of long-term debt, as a reduction to interest expense. During the nine months ended September 30, 2016 , Synovus reclassified $1.3 million from hedge-related basis adjustment, as a reduction to loss on early extinguishment of debt, net. As of September 30, 2017 , all deferred gains related to hedging relationships that had been previously terminated had been recognized into earnings.

Net Income Per Common Share

Net Income Per Common Share	9 Months Ended
	Sep. 30, 2017
Earnings Per Share [Abstract]
Net Income Per Common Share	Note 10 - Net Income Per Common Share The following table displays a reconciliation of the information used in calculating basic and diluted earnings per common share for the nine and three months ended September 30, 2017 and 2016 . Nine Months Ended September 30, Three Months Ended September 30, (in thousands, except per share data) 2017 2016 2017 2016 Basic Net Income Per Common Share: Net income available to common shareholders $ 238,190 170,555 $ 95,448 62,686 Weighted average common shares outstanding 121,796 125,076 120,900 122,924 Net income per common share, basic $ 1.96 1.36 $ 0.79 0.51 Diluted Net Income Per Common Share: Net income available to common shareholders $ 238,190 170,555 $ 95,448 62,686 Weighted average common shares outstanding 121,796 125,076 120,900 122,924 Potentially dilutive shares from outstanding equity-based awards and Earnout Payments 832 636 914 680 Weighted average diluted common shares 122,628 125,712 121,814 123,604 Net income per common share, diluted $ 1.94 1.36 $ 0.78 0.51 Basic net income per common share is computed by dividing net income by the average common shares outstanding for the period. Diluted net income per common share reflects the dilution that could occur if securities or other contracts to issue common stock were exercised or converted. The dilutive effect of outstanding options and restricted share units is reflected in diluted net income per common share, unless the impact is anti-dilutive, by application of the treasury stock method. As of September 30, 2017 and 2016 , there were 2.2 million and 2.5 million , respectively, potentially dilutive shares related to the Warrant and stock options to purchase shares of common stock that were outstanding during 2017 and 2016 , but were not included in the computation of diluted net income per common share because the effect would have been anti-dilutive.

Share-based Compensation

Share-based Compensation	9 Months Ended
	Sep. 30, 2017
Share-based Compensation [Abstract]
Share-based Compensation	Note 11 - Share-based Compensation General Description of Share-based Plans Synovus has a long-term incentive plan under which the Compensation Committee of the Board of Directors has the authority to grant share-based awards to Synovus employees. At September 30, 2017 , Synovus had a total of 5.7 million shares of its authorized but unissued common stock reserved for future grants under the 2013 Omnibus Plan. The 2013 Omnibus Plan authorizes 8.6 million common share equivalents available for grant, where grants of options count as one share equivalent and grants of full value awards (e.g., restricted share units, market restricted share units, and performance share units) count as two share equivalents. Any restricted share units that are forfeited and options that expire unexercised will again become available for issuance under the Plan. The Plan permits grants of share-based compensation including stock options, restricted share units, market restricted share units, and performance share units. The grants generally include vesting periods ranging from three to five years and contractual terms of ten years. Stock options are granted at exercise prices which equal the fair value of a share of common stock on the grant-date. Market restricted share units and performance share units are granted at target and are compared annually to required market and performance metrics to determine final units vested and compensation expense. Synovus has historically issued new shares to satisfy share option exercises and share unit conversions. Dividend equivalents are paid on outstanding restricted share units, market restricted share units, and performance share units in the form of additional restricted share units that vest over the same vesting period or the vesting period left on the original restricted share unit grant. Share-based Compensation Expense Total share-based compensation expense was $10.6 million and $3.7 million for the nine and three months ended September 30, 2017 , respectively, and $10.2 million and $3.4 million for the nine and three months ended September 30, 2016 , respectively. Stock Options No stock option grants were made during the nine months ended September 30, 2017 . At September 30, 2017 , there were 809 thousand outstanding stock options to purchase shares of common stock with a weighted average exercise price of $17.82 per share. Restricted Share Units, Performance Share Units, and Market Restricted Share Units During the nine months ended September 30, 2017 , Synovus awarded 235 thousand restricted share units that have a service-based vesting period of three years and awarded 73 thousand performance share units that vest upon service and performance conditions. Synovus also granted 73 thousand market restricted share units during the nine months ended September 30, 2017 . The weighted average grant-date fair value of the awarded restricted share units, performance share units and market restricted share units was $41.95 per share. Market restricted share units and performance share units are granted at target and are compared annually to required market and performance metrics. The performance share units vest upon meeting certain service and performance conditions. Return on average assets (ROAA) performance is evaluated each year over a three-year performance period, with share distribution determined at the end of the three years. The number of performance share units that will ultimately vest ranges from 0% to 150% of target based on Synovus' three-year weighted average ROAA (as defined). The market restricted share units have a three -year service-based vesting component as well as a total shareholder return multiplier. The number of market restricted share units that will ultimately vest ranges from 75% to 125% of target based on Synovus' total shareholder return. At September 30, 2017 , including dividend equivalents granted, there were 973 thousand restricted share units, performance share units and market restricted share units outstanding with a weighted average grant-date fair value of $32.91 per share.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 12 - Commitments and Contingencies In the normal course of business, Synovus enters into commitments to extend credit such as loan commitments and letters of credit to meet the financing needs of its customers. Synovus uses the same credit policies in making commitments and conditional obligations as it does for on-balance sheet instruments. Commitments to extend credit are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. The contractual amount of these financial instruments represents Synovus' maximum credit risk should the counterparty draw upon the commitment, and should the counterparty subsequently fail to perform according to the terms of the contract. Since many of the commitments are expected to expire without being drawn upon, total commitment amounts do not necessarily represent future cash requirements. Additionally, certain commitments (primarily consumer) can generally be canceled by providing notice to the borrower. The allowance for credit losses associated with unfunded commitments and letters of credit is a component of the unfunded commitments reserve recorded within other liabilities on the Consolidated Balance Sheets. Additionally, unearned fees relating to letters of credit are recorded within other liabilities on the Consolidated Balance Sheets. These amounts are not material to Synovus' Consolidated Balance Sheets. Unfunded lending commitments and letters of credit at September 30, 2017 and December 31, 2016 are presented below. (in thousands) September 30, 2017 December 31, 2016 Letters of credit* $ 152,082 150,948 Commitments to fund commercial real estate, construction, and land development loans 1,309,144 1,394,162 Unused credit card lines 1,170,429 1,103,431 Commitments under home equity lines of credit 1,133,569 1,096,052 Commitments to fund commercial and industrial loans 5,164,553 4,792,834 Other loan commitments 326,672 307,772 Total unfunded lending commitments and letters of credit $ 9,256,449 8,845,199 * Represent the contractual amount net of risk participations of approximately $63 million and $83 million at September 30, 2017 and December 31, 2016, respectively.

Legal Proceedings

Legal Proceedings	9 Months Ended
	Sep. 30, 2017
Legal Proceedings Disclosure [Abstract]
Legal Proceedings	Note 13 - Legal Proceedings Synovus and its subsidiaries are subject to various legal proceedings and claims that arise in the ordinary course of its business. Additionally, in the ordinary course of its business, Synovus and its subsidiaries are subject to regulatory examinations, information gathering requests, inquiries and investigations. Synovus, like many other financial institutions, has been the target of numerous legal actions and other proceedings asserting claims for damages and related relief for losses. These actions include claims and counterclaims asserted by individual borrowers related to their loans and allegations of violations of state and federal laws and regulations relating to banking practices, including putative class action matters. In addition to actual damages, if Synovus does not prevail in asserted legal actions, credit-related litigation could result in additional write-downs or charge-offs of loans, which could adversely affect Synovus' results of operations during the period in which the write-down or charge-off were to occur. Synovus carefully examines and considers each legal matter, and, in those situations where Synovus determines that a particular legal matter presents loss contingencies that are both probable and reasonably estimable, Synovus establishes an appropriate accrual. An event is considered to be probable if the future event is likely to occur. While the final outcome of any legal proceeding is inherently uncertain, based on the information currently available, advice of counsel and available insurance coverage, management believes that the amounts accrued with respect to legal matters as of September 30, 2017 are adequate. The actual costs of resolving legal claims may be higher or lower than the amounts accrued. In addition, where Synovus determines that there is a reasonable possibility of a loss in respect of legal matters, Synovus considers whether it is able to estimate the total reasonably possible loss or range of loss. An event is “reasonably possible” if “the chance of the future event or events occurring is more than remote but less than likely.” An event is “remote” if “the chance of the event or future event occurring is more than slight but less than reasonably possible." In many situations, Synovus may be unable to estimate reasonably possible losses due to the preliminary nature of the legal matters, as well as a variety of other factors and uncertainties. For those legal matters where Synovus is able to estimate a range of reasonably possible losses, management currently estimates the aggregate range from our outstanding litigation is from zero to $10 million in excess of the amounts accrued, if any, related to those matters. This estimated aggregate range is based upon information currently available to Synovus, and the actual losses could prove to be lower or higher. As there are further developments in these legal matters, Synovus will reassess these matters, and the estimated range of reasonably possible losses may change as a result of this assessment. Based on Synovus' current knowledge and advice of counsel, management presently does not believe that the liabilities arising from these legal matters will have a material adverse effect on Synovus' consolidated financial condition, results of operations or cash flows. However, it is possible that the ultimate resolution of these legal matters could have a material adverse effect on Synovus' results of operations for any particular period. Synovus intends to vigorously pursue all available defenses to these legal matters, but will also consider other alternatives, including settlement, in situations where there is an opportunity to resolve such legal matters on terms that Synovus considers to be favorable, including in light of the continued expense and distraction of defending such legal matters. Synovus maintains insurance coverage, which may be available to cover legal fees, or potential losses that might be incurred in connection with such legal matters. The above-noted estimated range of reasonably possible losses does not take into consideration insurance coverage which may or may not be available for the respective legal matters.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2017
Subsequent Events [Abstract]
Subsequent Events	Note 14 - Subsequent Events On September 25, 2017, Synovus issued a notice of redemption to redeem all of the $300.0 million aggregate principal amount of its outstanding 7.875% senior notes due 2019 on November 9, 2017 at a “make whole” premium, plus accrued but unpaid interest on the 2019 notes to the redemption date. The results for the three months ending December 31, 2017 will include a pre-tax loss of approximately $24 million related to early extinguishment of these notes. On November 1, 2017, Synovus completed a public offering of $300.0 million of 3.125% senior notes due 2022. Proceeds from this offering will be used, in part, to fund the redemption of the 2019 notes.

Significant Accounting Polici23

Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2017
Accounting Policies [Abstract]
Basis of Presentation	The accompanying unaudited interim consolidated financial statements have been prepared in accordance with the instructions to the SEC Form 10-Q and Article 10 of Regulation S-X; therefore, they do not include all information and footnotes necessary for a fair presentation of financial position, results of operations, comprehensive income, and cash flows in conformity with GAAP. All adjustments consisting of normally recurring accruals that, in the opinion of management, are necessary for a fair presentation of the consolidated financial position and results of operations for the periods covered by this Report have been included. The accompanying unaudited interim consolidated financial statements should be read in conjunction with the consolidated financial statements and related notes appearing in Synovus' 2016 Form 10-K. There have been no significant changes to the accounting policies as disclosed in Synovus' 2016 Form 10-K. In preparing the unaudited interim consolidated financial statements in accordance with GAAP, management is required to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities as of the date of the respective consolidated balance sheets and the reported amounts of revenues and expenses for the periods presented. Actual results could differ significantly from those estimates. Material estimates that are particularly susceptible to significant change relate to the determination of the allowance for loan losses, the fair value of investment securities, and the fair value of private equity investments.
Cash and Cash Equivalents	Cash and cash equivalents consist of cash and due from banks.
Short-term Investment	Short-term investments consist of interest bearing funds with the Federal Reserve Bank, interest earning deposits with banks, and federal funds sold and securities purchased under resale agreements.
Recently Adopted Accounting Standards Updates	During 2016, the FASB issued ASU 2016-09, Compensation-Stock Compensation: Improvements to Employee Share-Based Payment Accounting. ASU 2016-09 simplified various aspects of the accounting for employee share-based payment transactions for both public and nonpublic entities, including the accounting for income taxes, forfeitures, and statutory tax withholding requirements, as well as classification in the statement of cash flows. This accounting standard update included a requirement to record all tax effects associated with share-based compensation through the income statement. Prior to 2017, tax benefits in excess of compensation cost (“windfalls”) and tax deficiencies (“shortfalls”) were recorded in equity. During the nine and three months ended September 30, 2017 , Synovus recognized $4.7 million and $211 thousand , respectively, of income tax benefits from excess tax benefits that occurred during the nine months ended September 30, 2017 from the vesting of restricted share units and exercise of stock options. As of January 1, 2017, Synovus had no previously unrecognized excess tax benefits. Additionally, beginning January 1, 2017, Synovus modified the denominator in the diluted earnings per common share calculation under the treasury stock method to exclude future excess tax benefits as part of the assumed proceeds. Synovus elected to retain its existing accounting policy election to estimate award forfeitures. During 2015, the FASB issued ASU 2015-17, Income Taxes: Balance Sheet Classification of Deferred Taxes , which became effective January 1, 2017. ASU 2015-17 required deferred income tax liabilities and assets be classified as noncurrent in the statement of financial position instead of separating deferred taxes into current and noncurrent amounts. Also, valuation allowances will no longer be classified between current and noncurrent because these allowances will be required to be classified as noncurrent under the new standard. This ASU only impacts classification in the balance sheet, and has no impact on required deferred tax footnote disclosures (i.e., required presentation of “gross” deferred tax assets and “gross” deferred tax liabilities). The current requirement that deferred tax liabilities and assets of a tax-paying component of an entity be offset and presented as a single amount is not affected by this ASU. There is no impact to our balance sheet as a result of this standard because Synovus has not historically distinguished deferred taxes on the balance sheet as current vs. non-current.
Reclassifications	Prior periods' consolidated financial statements are reclassified whenever necessary to conform to the current periods' presentation.

Acquisitions (Tables)

Acquisitions (Tables)	9 Months Ended
	Sep. 30, 2017
Business Combinations [Abstract]
Schedule of Business Acquisition	Global One October 1, 2016 (in thousands) Fair Value Assets acquired: Cash and due from banks $ 9,554 Commercial and industrial loans (1) 357,307 Goodwill (2) 32,884 Other intangible assets 12,500 Other assets 3,681 Total assets acquired $ 415,926 Liabilities assumed: Notes payable (3) $ 358,560 Contingent consideration 12,234 Deferred tax liability, net 3,229 Other liabilities 11,903 Total liabilities assumed $ 385,926 Consideration paid $ 30,000 Cash paid $ 3,408 Fair value of common stock issued 26,592 (1) The unpaid principal balance of the loans was $356.7 million . (2) The goodwill is not expected to be deductible for tax purposes. (3) The unpaid principal balance of the notes payable was $357.0 million .

Investment Securities (Tables)

Investment Securities (Tables)	9 Months Ended
	Sep. 30, 2017
Investments [Abstract]
Summary of Available-for-Sale Investment Securities	The amortized cost, gross unrealized gains and losses, and estimated fair values of investment securities available for sale at September 30, 2017 and December 31, 2016 are summarized below. September 30, 2017 (in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury securities $ 83,550 — (369 ) 83,181 U.S. Government agency securities 10,772 266 — 11,038 Mortgage-backed securities issued by U.S. Government agencies 127,521 715 (852 ) 127,384 Mortgage-backed securities issued by U.S. Government sponsored enterprises 2,663,959 7,917 (20,024 ) 2,651,852 Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises 943,583 — (12,143 ) 931,440 State and municipal securities 180 1 — 181 Corporate debt and other securities 20,297 286 (216 ) 20,367 Total investment securities available for sale $ 3,849,862 9,185 (33,604 ) 3,825,443 December 31, 2016 (in thousands) Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury securities $ 108,221 225 (644 ) 107,802 U.S. Government agency securities 12,727 266 — 12,993 Mortgage-backed securities issued by U.S. Government agencies 174,440 1,116 (1,354 ) 174,202 Mortgage-backed securities issued by U.S. Government sponsored enterprises 2,543,495 5,416 (42,571 ) 2,506,340 Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises 905,789 1,214 (16,561 ) 890,442 State and municipal securities 2,780 14 — 2,794 Equity securities 919 2,863 — 3,782 Corporate debt and other securities 20,247 — (407 ) 19,840 Total investment securities available for sale $ 3,768,618 11,114 (61,537 ) 3,718,195
Schedule of Unrealized Loss on Investments	Gross unrealized losses on investment securities and the fair value of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, at September 30, 2017 and December 31, 2016 are presented below. September 30, 2017 Less than 12 Months 12 Months or Longer Total (in thousands) Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses U.S. Treasury securities $ 64,351 369 — — 64,351 369 Mortgage-backed securities issued by U.S. Government agencies 80,303 552 7,636 300 87,939 852 Mortgage-backed securities issued by U.S. Government sponsored enterprises 1,696,906 19,128 48,596 896 1,745,502 20,024 Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises 569,191 5,617 240,355 6,526 809,546 12,143 Corporate debt and other securities — — 5,081 216 5,081 216 Total $ 2,410,751 25,666 301,668 7,938 2,712,419 33,604 December 31, 2016 Less than 12 Months 12 Months or Longer Total (in thousands) Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses Fair Value Gross Unrealized Losses U.S. Treasury securities $ 64,023 644 — — 64,023 644 Mortgage-backed securities issued by U.S. Government agencies 128,121 1,240 3,626 114 131,747 1,354 Mortgage-backed securities issued by U.S. Government sponsored enterprises 2,123,181 42,571 — — 2,123,181 42,571 Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises 682,492 15,653 24,801 908 707,293 16,561 Corporate debt and other securities 14,952 48 4,888 359 19,840 407 Total $ 3,012,769 60,156 33,315 1,381 3,046,084 61,537
Amortized Cost and Estimated Fair Value by Contractual Maturity of Investment Securities Available-for-Sale	For purposes of the maturity table, mortgage-backed securities and CMOs, which are not due at a single maturity date, have been classified based on the final contractual maturity date. Distribution of Maturities at September 30, 2017 (in thousands) Within One Year 1 to 5 Years 5 to 10 Years More Than 10 Years No Stated Maturity Total Amortized Cost U.S. Treasury securities $ 18,830 64,720 — — — 83,550 U.S. Government agency securities 2,331 6,437 2,004 — — 10,772 Mortgage-backed securities issued by U.S. Government agencies — — 32,956 94,565 — 127,521 Mortgage-backed securities issued by U.S. Government sponsored enterprises 44 2,015 446,255 2,215,645 — 2,663,959 Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises — — 20,910 922,673 — 943,583 State and municipal securities 180 — — — — 180 Corporate debt and other securities — — 15,000 2,000 3,297 20,297 Total amortized cost $ 21,385 73,172 517,125 3,234,883 3,297 3,849,862 Fair Value U.S. Treasury securities $ 18,830 64,351 — — — 83,181 U.S. Government agency securities 2,385 6,529 2,124 — — 11,038 Mortgage-backed securities issued by U.S. Government agencies — — 33,073 94,311 — 127,384 Mortgage-backed securities issued by U.S. Government sponsored enterprises 45 2,127 444,701 2,204,979 — 2,651,852 Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises — — 20,666 910,774 — 931,440 State and municipal securities 181 — — — — 181 Corporate debt and other securities — — 15,286 1,919 3,162 20,367 Total fair value $ 21,441 73,007 515,850 3,211,983 3,162 3,825,443
Schedule of Activity for Available-for-Sale Securities	Proceeds from sales, gross gains, and gross losses on sales of securities available for sale for the nine and three months ended September 30, 2017 and 2016 are presented below. The specific identification method is used to reclassify gains and losses out of other comprehensive income at the time of sale. Nine Months Ended September 30, Three Months Ended September 30, (in thousands) 2017 2016 2017 2016 Proceeds from sales of investment securities available for sale $ 812,293 596,824 $ 473,912 353,215 Gross realized gains on sales 7,942 2,590 — 1,635 Gross realized losses on sales (8,231 ) (2,464 ) (7,956 ) (1,576 ) Investment securities (losses) gains, net $ (289 ) 126 $ (7,956 ) 59

Restructuring Charges (Tables)

Restructuring Charges (Tables)	9 Months Ended
	Sep. 30, 2017
Restructuring Charges [Abstract]
Schedule of Restructuring and Related Costs	For the nine and three months ended September 30, 2017 and 2016 , total restructuring charges consist of the following components: Nine Months Ended September 30, Three Months Ended September 30, (in thousands) 2017 2016 2017 2016 Severance charges $ 6,428 — $ (24 ) — Asset impairment charges 511 8,120 515 1,240 Other charges 104 105 28 3 Total restructuring charges, net $ 7,043 8,225 $ 519 1,243 The following tables present aggregate activity within the accrual for restructuring charges for the nine and three months ended September 30, 2017 and 2016 : (in thousands) Severance Charges Lease Termination Charges Total Balance at December 31, 2016 $ 81 3,968 4,049 Accruals for voluntary and involuntary termination benefits 6,428 — 6,428 Payments (5,304 ) (540 ) (5,844 ) Balance at September 30, 2017 $ 1,205 3,428 4,633 Balance at July 1, 2017 3,731 3,530 7,261 Accruals for voluntary and involuntary termination benefits (24 ) — (24 ) Payments (2,502 ) (102 ) (2,604 ) Balance at September 30, 2017 $ 1,205 3,428 4,633 (in thousands) Severance Charges Lease Termination Charges Total Balance at December 31, 2015 $ 1,930 4,687 6,617 Accruals for lease terminations — 6 6 Payments (1,702 ) (533 ) (2,235 ) Balance at September 30, 2016 $ 228 4,160 4,388 Balance at July 1, 2016 593 4,375 4,968 Accruals for lease terminations — (25 ) (25 ) Payments (365 ) (190 ) (555 ) Balance at September 30, 2016 $ 228 4,160 4,388

Loans and Allowance for Loan 27

Loans and Allowance for Loan Losses (Tables)	9 Months Ended
	Sep. 30, 2017
Loans and Allowance for Loan Losses [Abstract]
Schedule of Current, Accruing Past Due, and Nonaccrual Loans	The following is a summary of current, accruing past due, and non-accrual loans by portfolio class as of September 30, 2017 and December 31, 2016 . Current, Accruing Past Due, and Non-accrual Loans September 30, 2017 (in thousands) Current Accruing 30-89 Days Past Due Accruing 90 Days or Greater Past Due Total Accruing Past Due Non-accrual Total Investment properties $ 5,919,393 3,454 186 3,640 2,063 5,925,096 1-4 family properties 784,520 6,588 796 7,384 2,712 794,616 Land and development 494,488 5,732 65 5,797 6,927 507,212 Total commercial real estate 7,198,401 15,774 1,047 16,821 11,702 7,226,924 Commercial, financial and agricultural 6,871,204 30,010 2,356 32,366 58,139 6,961,709 Owner-occupied 4,751,269 9,586 618 10,204 3,960 4,765,433 Total commercial and industrial 11,622,473 39,596 2,974 42,570 62,099 11,727,142 Home equity lines 1,505,556 7,535 160 7,695 15,638 1,528,889 Consumer mortgages 2,545,986 5,225 137 5,362 6,332 2,557,680 Credit cards 222,176 2,312 1,237 3,549 — 225,725 Other consumer loans 1,234,355 8,726 130 8,856 2,067 1,245,278 Total consumer 5,508,073 23,798 1,664 25,462 24,037 5,557,572 Total loans $ 24,328,947 79,168 5,685 84,853 97,838 24,511,638 (1 ) December 31, 2016 (in thousands) Current Accruing 30-89 Days Past Due Accruing 90 Days or Greater Past Due Total Accruing Past Due Non-accrual Total Investment properties $ 5,861,198 2,795 — 2,795 5,268 5,869,261 1-4 family properties 873,231 4,801 161 4,962 9,114 887,307 Land and development 598,624 1,441 — 1,441 16,233 616,298 Total commercial real estate 7,333,053 9,037 161 9,198 30,615 7,372,866 Commercial, financial and agricultural 6,839,699 9,542 720 10,262 59,074 6,909,035 Owner-occupied 4,601,356 17,913 244 18,157 16,503 4,636,016 Total commercial and industrial 11,441,055 27,455 964 28,419 75,577 11,545,051 Home equity lines 1,585,228 10,013 473 10,486 21,551 1,617,265 Consumer mortgages 2,265,966 7,876 81 7,957 22,681 2,296,604 Credit cards 229,177 1,819 1,417 3,236 — 232,413 Other consumer loans 809,419 5,771 39 5,810 2,954 818,183 Total consumer 4,889,790 25,479 2,010 27,489 47,186 4,964,465 Total loans $ 23,663,898 61,971 3,135 65,106 153,378 23,882,382 (2 ) (1) Total before net deferred fees and costs of $24.3 million . (2) Total before net deferred fees and costs of $26.0 million .
Loan Portfolio Credit Exposure	In the following tables, consumer loans are generally assigned a risk grade similar to the classifications described above; however, upon reaching 90 days and 120 days past due, they are generally downgraded to Substandard and Loss, respectively, in accordance with the FFIEC Uniform Retail Credit Classification and Account Management Policy. Additionally, in accordance with the Interagency Supervisory Guidance on Allowance for Loan and Lease Losses Estimation Practices for Loans and Lines of Credit Secured by Junior Liens on 1-4 Family Residential Properties, the risk grade classifications of consumer loans (home equity lines and consumer mortgages) secured by junior liens on 1-4 family residential properties also consider available information on the payment status of any associated senior liens with other financial institutions. Loan Portfolio Credit Exposure by Risk Grade September 30, 2017 (in thousands) Pass Special Mention Substandard (1) Doubtful (2) Loss Total Investment properties $ 5,847,902 60,423 16,771 — — 5,925,096 1-4 family properties 756,665 20,286 17,438 227 — 794,616 Land and development 451,141 36,523 16,419 3,129 — 507,212 Total commercial real estate 7,055,708 117,232 50,628 3,356 — 7,226,924 Commercial, financial and agricultural 6,704,805 106,117 149,456 1,250 81 (3) 6,961,709 Owner-occupied 4,632,930 52,797 79,633 73 — 4,765,433 Total commercial and industrial 11,337,735 158,914 229,089 1,323 81 11,727,142 Home equity lines 1,505,724 — 20,771 355 2,039 (3) 1,528,889 Consumer mortgages 2,547,272 — 10,125 177 106 (3) 2,557,680 Credit cards 224,488 — 523 — 714 (4) 225,725 Other consumer loans 1,242,211 — 2,754 299 14 (3) 1,245,278 Total consumer 5,519,695 — 34,173 831 2,873 5,557,572 Total loans $ 23,913,138 276,146 313,890 5,510 2,954 24,511,638 (5 ) December 31, 2016 (in thousands) Pass Special Mention Substandard (1) Doubtful (2) Loss Total Investment properties $ 5,794,626 43,336 31,299 — — 5,869,261 1-4 family properties 826,311 33,928 26,790 278 — 887,307 Land and development 521,745 60,205 27,361 6,987 — 616,298 Total commercial real estate 7,142,682 137,469 85,450 7,265 — 7,372,866 Commercial, financial and agricultural 6,635,756 126,268 140,425 6,445 141 (3) 6,909,035 Owner-occupied 4,462,420 60,856 111,330 1,410 — 4,636,016 Total commercial and industrial 11,098,176 187,124 251,755 7,855 141 11,545,051 Home equity lines 1,589,199 — 22,774 2,892 2,400 (3) 1,617,265 Consumer mortgages 2,271,916 — 23,268 1,283 137 (3) 2,296,604 Credit cards 230,997 — 637 — 779 (4) 232,413 Other consumer loans 814,844 — 3,233 42 64 (3) 818,183 Total consumer 4,906,956 — 49,912 4,217 3,380 4,964,465 Total loans $ 23,147,814 324,593 387,117 19,337 3,521 23,882,382 (6 ) (1) Includes $224.5 million and $256.6 million of Substandard accruing loans at September 30, 2017 and December 31, 2016 , respectively. (2) The loans within this risk grade are on non-accrual status. Commercial loans generally have an allowance for loan losses in accordance with ASC 310, and retail loans generally have an allowance for loan losses equal to 50% of the loan amount. (3) The loans within this risk grade are on non-accrual status and have an allowance for loan losses equal to the full loan amount. (4) Represent amounts that were 120 days past due. These credits are downgraded to the Loss category with an allowance for loan losses equal to the full loan amount and are generally charged off upon reaching 181 days past due in accordance with the FFIEC Uniform Retail Credit Classification and Account Management Policy. (5) Total before net deferred fees and costs of $24.3 million . (6) Total before net deferred fees and costs of $26.0 million .
Schedule of Allowances for Loan Losses and Recorded Investment in Loans	The following table details the changes in the allowance for loan losses by loan segment for the nine and three months ended September 30, 2017 . Allowance for Loan Losses and Recorded Investment in Loans As Of and For The Nine Months Ended September 30, 2017 (in thousands) Commercial Real Estate Commercial & Industrial Retail Total Allowance for loan losses: Beginning balance $ 81,816 125,778 44,164 251,758 Charge-offs (11,336 ) (41,390 ) (24,023 ) (76,749 ) Recoveries 6,191 5,181 4,682 16,054 Provision for loan losses 1,289 36,934 20,397 58,620 Ending balance (1) $ 77,960 126,503 45,220 249,683 Ending balance: individually evaluated for impairment 4,108 7,360 783 12,251 Ending balance: collectively evaluated for impairment $ 73,852 119,143 44,437 237,432 Loans: Ending balance: total loans (1)(2) $ 7,226,924 11,727,142 5,557,572 24,511,638 Ending balance: individually evaluated for impairment 64,909 109,434 30,132 204,475 Ending balance: collectively evaluated for impairment $ 7,162,015 11,617,708 5,527,440 24,307,163 As Of and For The Nine Months Ended September 30, 2016 (in thousands) Commercial Real Estate Commercial & Industrial Retail Total Allowance for loan losses: Beginning balance $ 87,133 122,989 42,374 252,496 Charge-offs (13,361 ) (17,098 ) (10,611 ) (41,070 ) Recoveries 10,927 6,122 3,601 20,650 Provision for loan losses (3,597 ) 18,875 6,463 21,741 Ending balance (1) $ 81,102 130,888 41,827 253,817 Ending balance: individually evaluated for impairment 11,066 11,474 1,724 24,264 Ending balance: collectively evaluated for impairment $ 70,036 119,414 40,103 229,553 Loans: Ending balance: total loans (1)(3) $7,472,551 11,009,021 4,807,511 23,289,083 Ending balance: individually evaluated for impairment 102,837 118,442 37,820 259,099 Ending balance: collectively evaluated for impairment $ 7,369,714 10,890,579 4,769,691 23,029,984 (1) As of and for the nine months ended September 30, 2017 and 2016 , there were no purchased credit-impaired loans and no allowance for loan losses for purchased credit-impaired loans. (2) Total before net deferred fees and costs of $24.3 million . (3) Total before net deferred fees and costs of $26.2 million . Allowance for Loan Losses and Recorded Investment in Loans As Of and For The Three Months Ended September 30, 2017 (in thousands) Commercial Real Estate Commercial & Industrial Consumer Total Allowance for loan losses: Beginning balance $ 77,527 123,437 47,131 248,095 Charge-offs (8,129 ) (21,855 ) (14,367 ) (44,351 ) Recoveries 2,543 1,899 1,811 6,253 Provision for loan losses 6,019 23,022 10,645 39,686 Ending balance (1) $ 77,960 126,503 45,220 249,683 Ending balance: individually evaluated for impairment 4,108 7,360 783 12,251 Ending balance: collectively evaluated for impairment $ 73,852 119,143 44,437 237,432 Loans: Ending balance: total loans (1)(2) $ 7,226,924 11,727,142 5,557,572 24,511,638 Ending balance: individually evaluated for impairment 64,909 109,434 30,132 204,475 Ending balance: collectively evaluated for impairment $ 7,162,015 11,617,708 5,527,440 24,307,163 As Of and For The Three Months Ended September 30, 2016 (in thousands) Commercial Real Estate Commercial & Industrial Consumer Total Allowance for loan losses: Beginning balance $ 79,359 129,633 46,084 255,076 Charge-offs (4,084 ) (6,437 ) (3,463 ) (13,984 ) Recoveries 4,237 1,780 1,037 7,054 Provision for loan losses 1,590 5,912 (1,831 ) 5,671 Ending balance (1) $ 81,102 130,888 41,827 253,817 Ending balance: individually evaluated for impairment 11,066 11,474 1,724 24,264 Ending balance: collectively evaluated for impairment $ 70,036 119,414 40,103 229,553 Loans: Ending balance: total loans (1)(3) $ 7,472,551 11,009,021 4,807,511 23,289,083 Ending balance: individually evaluated for impairment 102,837 118,442 37,820 259,099 Ending balance: collectively evaluated for impairment $ 7,369,714 10,890,579 4,769,691 23,029,984 (1 ) As of and for the three months ended September 30, 2017 and 2016 , there were no purchased credit-impaired loans and no allowance for loan losses for purchased credit-impaired loans. (2) Total before net deferred fees and costs of $24.3 million . (3) Total before net deferred fees and costs of $26.2 million .
Schedule of Impaired Loans	The tables below summarize impaired loans (including accruing TDRs) as of September 30, 2017 and December 31, 2016 . Impaired Loans (including accruing TDRs) September 30, 2017 Nine Months Ended September 30, 2017 Three Months Ended September 30, 2017 (in thousands) Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized Average Recorded Investment Interest Income Recognized With no related allowance recorded Investment properties $ — — — 164 — — — 1-4 family properties 253 2,582 — 374 — 253 — Land and development 1,488 3,172 — 2,084 — 1,911 — Total commercial real estate 1,741 5,754 — 2,622 — 2,164 — Commercial, financial and agricultural 20,696 22,122 — 23,094 — 25,583 — Owner-occupied 97 744 — 8,875 — 7,164 — Total commercial and industrial 20,793 22,866 — 31,969 — 32,747 — Home equity lines 1,072 1,072 — 1,063 — 1,069 — Consumer mortgages — — — 661 — 496 — Credit cards — — — — — — — Other consumer loans — — — — — — — Total consumer 1,072 1,072 — 1,724 — 1,565 — Total impaired loans with no related allowance recorded $ 23,606 29,692 — 36,315 — 36,476 — With allowance recorded Investment properties $ 28,651 28,651 1,116 29,325 903 28,826 306 1-4 family properties 15,741 15,741 452 16,552 664 15,665 278 Land and development 18,776 18,832 2,540 24,825 347 18,544 48 Total commercial real estate 63,168 63,224 4,108 70,702 1,914 63,035 632 Commercial, financial and agricultural 51,819 52,019 5,730 48,694 1,175 53,040 388 Owner-occupied 36,822 36,855 1,630 41,627 1,002 37,004 328 Total commercial and industrial 88,641 88,874 7,360 90,321 2,177 90,044 716 Home equity lines 5,995 5,995 119 7,807 265 6,534 82 Consumer mortgages 18,336 18,336 382 19,270 687 18,369 222 Credit cards — — — — — — — Other consumer loans 4,729 4,729 282 4,507 191 4,224 59 Total consumer 29,060 29,060 783 31,584 1,143 29,127 363 Total impaired loans with allowance recorded $ 180,869 181,158 12,251 192,607 5,234 182,206 1,711 Total impaired loans Investment properties $ 28,651 28,651 1,116 29,489 903 28,826 306 1-4 family properties 15,994 18,323 452 16,926 664 15,918 278 Land and development 20,264 22,004 2,540 26,909 347 20,455 48 Total commercial real estate 64,909 68,978 4,108 73,324 1,914 65,199 632 Commercial, financial and agricultural 72,515 74,141 5,730 71,788 1,175 78,623 388 Owner-occupied 36,919 37,599 1,630 50,502 1,002 44,168 328 Total commercial and industrial 109,434 111,740 7,360 122,290 2,177 122,791 716 Home equity lines 7,067 7,067 119 8,870 265 7,603 82 Consumer mortgages 18,336 18,336 382 19,931 687 18,865 222 Credit cards — — — — — — — Other consumer loans 4,729 4,729 282 4,507 191 4,224 59 Total consumer 30,132 30,132 783 33,308 1,143 30,692 363 Total impaired loans $ 204,475 210,850 12,251 228,922 5,234 218,682 1,711 Impaired Loans (including accruing TDRs) December 31, 2016 Year Ended December 31, 2016 (in thousands) Recorded Investment Unpaid Principal Balance Related Allowance Average Recorded Investment Interest Income Recognized With no related allowance recorded Investment properties $ 748 793 — 2,013 — 1-4 family properties 643 2,939 — 1,021 — Land and development 2,099 7,243 — 6,769 — Total commercial real estate 3,490 10,975 — 9,803 — Commercial, financial and agricultural 17,958 20,577 — 6,321 — Owner-occupied 5,508 7,377 — 8,394 — Total commercial and industrial 23,466 27,954 — 14,715 — Home equity lines 1,051 1,051 — 1,045 — Consumer mortgages 744 814 — 870 — Credit cards — — — — — Other consumer loans — — — — — Total consumer 1,795 1,865 — 1,915 — Total impaired loans with no related allowance recorded $ 28,751 40,794 — 26,433 — With allowance recorded Investment properties $ 31,489 31,489 2,044 42,659 1,436 1-4 family properties 23,642 23,649 769 39,864 855 Land and development 32,789 32,788 5,103 25,568 995 Total commercial real estate 87,920 87,926 7,916 108,091 3,286 Commercial, financial and agricultural 43,386 45,913 5,687 51,968 1,215 Owner-occupied 53,708 53,942 2,697 52,300 1,946 Total commercial and industrial 97,094 99,855 8,384 104,268 3,161 Home equity lines 9,638 9,638 971 9,668 432 Consumer mortgages 20,953 20,953 673 20,993 1,014 Credit cards — — — — — Other consumer loans 5,140 5,140 167 5,062 303 Total consumer 35,731 35,731 1,811 35,723 1,749 Total impaired loans with allowance recorded $ 220,745 223,512 18,111 248,082 8,196 Total impaired loans Investment properties $ 32,237 32,282 2,044 44,672 1,436 1-4 family properties 24,285 26,588 769 40,885 855 Land and development 34,888 40,031 5,103 32,337 995 Total commercial real estate 91,410 98,901 7,916 117,894 3,286 Commercial, financial and agricultural 61,344 66,490 5,687 58,289 1,215 Owner-occupied 59,216 61,319 2,697 60,694 1,946 Total commercial and industrial 120,560 127,809 8,384 118,983 3,161 Home equity lines 10,689 10,689 971 10,713 432 Consumer mortgages 21,697 21,767 673 21,863 1,014 Credit cards — — — — — Other consumer loans 5,140 5,140 167 5,062 303 Total consumer 37,526 37,596 1,811 37,638 1,749 Total impaired loans $ 249,496 264,306 18,111 274,515 8,196
Troubled Debt Restructurings	The following tables represent, by concession type, the post-modification balance for loans modified or renewed during the nine and three months ended September 30, 2017 and 2016 that were reported as accruing or non-accruing TDRs. TDRs by Concession Type Nine Months Ended September 30, 2017 (in thousands, except contract data) Number of Contracts Principal Forgiveness Below Market Interest Rate Term Extensions and/or Other Concessions Total Investment properties — $ — — — — 1-4 family properties 21 — 2,090 1,477 3,567 Land acquisition 4 — 157 895 1,052 Total commercial real estate 25 — 2,247 2,372 4,619 Commercial, financial and agricultural 50 — 8,703 12,145 20,848 Owner-occupied 4 — 35 1,705 1,740 Total commercial and industrial 54 — 8,738 13,850 22,588 Home equity lines — — — — — Consumer mortgages 8 — 248 1,190 1,438 Credit cards — — — — — Other retail loans 25 — 682 958 1,640 Total retail 33 — 930 2,148 3,078 Total TDRs 112 $ — 11,915 18,370 30,285 (1 ) Three Months Ended September 30, 2017 (in thousands, except contract data) Number of Contracts Principal Forgiveness Below Market Interest Rate Term Extensions and/or Other Concessions Total Investment properties — $ — — — — 1-4 family properties 5 — — 964 964 Land and development 3 — 157 760 917 Total commercial real estate 8 — 157 1,724 1,881 Commercial, financial and agricultural 22 — 2,943 5,866 8,809 Owner-occupied 3 — 35 1,683 1,718 Total commercial and industrial 25 — 2,978 7,549 10,527 Home equity lines — — — — — Consumer mortgages 7 — 248 1,181 1,429 Credit cards — — — — — Other consumer loans 17 — 682 388 1,070 Total consumer 24 — 930 1,569 2,499 Total TDRs 57 $ — 4,065 10,842 14,907 (1 ) (1) No net charge-offs were recorded during the nine and three months ended September 30, 2017 upon restructuring of these loans. TDRs by Concession Type Nine Months Ended September 30, 2016 (in thousands, except contract data) Number of Contracts Principal Forgiveness Below Market Interest Rate Term Extensions and/or Other Concessions Total Investment properties 4 $ — 1,826 3,518 5,344 1-4 family properties 23 — 3,703 1,211 4,914 Land acquisition 13 — — 1,766 1,766 Total commercial real estate 40 — 5,529 6,495 12,024 Commercial, financial and agricultural 50 — 13,948 5,232 19,180 Owner-occupied 7 — 5,458 550 6,008 Total commercial and industrial 57 — 19,406 5,782 25,188 Home equity lines 5 — 224 123 347 Consumer mortgages 6 — 354 51 405 Credit cards — — — — — Other retail loans 24 — 394 1,828 2,222 Total retail 35 — 972 2,002 2,974 Total TDRs 132 $ — 25,907 14,279 40,186 (2 ) Three Months Ended September 30, 2016 (in thousands, except contract data) Number of Contracts Principal Forgiveness Below Market Interest Rate Term Extensions and/or Other Concessions Total Investment properties 1 $ — — 3,370 3,370 1-4 family properties 4 — 213 47 260 Land and development 2 — — 497 497 Total commercial real estate 7 — 213 3,914 4,127 Commercial, financial and agricultural 5 — — 387 387 Owner-occupied 1 — 2,791 — 2,791 Total commercial and industrial 6 — 2,791 387 3,178 Home equity lines 2 — — 123 123 Consumer mortgages — — — — — Credit cards — — — — — Other consumer loans 7 — 70 294 364 Total consumer 9 — 70 417 487 Total TDRs 22 $ — 3,074 4,718 7,792 (2 ) (2) No net charge-offs were recorded during the nine and three months ended September 30, 2016 upon restructuring of these loans.

Other Comprehensive Income (L28

Other Comprehensive Income (Loss) (Tables)	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Schedule of Changes in Accumulated Other Comprehensive Income (Loss) by Component (Net of Income Taxes)	The following tables illustrate activity within the balances in accumulated other comprehensive income (loss) by component for the nine and three months ended September 30, 2017 and 2016 . Changes in Accumulated Other Comprehensive Income (Loss) by Component (Net of Income Taxes) (in thousands) Net unrealized gains (losses) on cash flow hedges Net unrealized gains (losses) on investment securities available for sale Post-retirement unfunded health benefit Total Balance at December 31, 2016 $ (12,217 ) (44,324 ) 882 (55,659 ) Other comprehensive income before reclassifications — 15,812 38 15,850 Amounts reclassified from accumulated other comprehensive income (loss) 80 178 (45 ) 213 Net current period other comprehensive income 80 15,990 (7 ) 16,063 Balance as of September 30, 2017 $ (12,137 ) (28,334 ) 875 (39,596 ) Balance as of July 1, 2017 $ (12,137 ) (36,586 ) 858 (47,865 ) Other comprehensive income before reclassifications — 3,359 38 3,397 Amounts reclassified from accumulated other comprehensive income (loss) — 4,893 (21 ) 4,872 Net current period other comprehensive income — 8,252 17 8,269 Balance as of September 30, 2017 $ (12,137 ) (28,334 ) 875 (39,596 ) Changes in Accumulated Other Comprehensive Income (Loss) by Component (Net of Income Taxes) (in thousands) Net unrealized gains (losses) on cash flow hedges Net unrealized gains (losses) on investment securities available for sale Post-retirement unfunded health benefit Total Balance at December 31, 2015 $ (12,504 ) (18,222 ) 907 (29,819 ) Other comprehensive income before reclassifications — 34,827 63 34,890 Amounts reclassified from accumulated other comprehensive income (loss) 247 (77 ) (76 ) 94 Net current period other comprehensive income 247 34,750 (13 ) 34,984 Balance as of September 30, 2016 $ (12,257 ) 16,528 894 5,165 Balance as of July 1, 2016 $ (12,297 ) 22,459 843 11,005 Other comprehensive income (loss) before reclassifications — (5,895 ) 63 (5,832 ) Amounts reclassified from accumulated other comprehensive income (loss) 40 (36 ) (12 ) (8 ) Net current period other comprehensive income (loss) 40 (5,931 ) 51 (5,840 ) Balance as of September 30, 2016 $ (12,257 ) 16,528 894 5,165
Schedule of Reclassifications out of Accumulated Other Comprehensive Income (Loss)	Reclassifications out of Accumulated Other Comprehensive Income (Loss) Details About Accumulated Other Comprehensive Income (Loss) Components Amount Reclassified from Accumulated Other Comprehensive Income (Loss) Affected Line Item in the Statement Where Net Income is Presented For the Nine Months Ended September 30, 2017 2016 Net unrealized gains (losses) on cash flow hedges: Amortization of deferred losses $ (130 ) (205 ) Interest expense Amortization of deferred losses — (197 ) Loss on early extinguishment of debt, net 50 155 Income tax (expense) benefit $ (80 ) (247 ) Reclassifications, net of income taxes Net unrealized (losses) gains on investment securities available for sale: Realized (losses) gains on sale of securities $ (289 ) 126 Investment securities (losses) gains, net 111 (49 ) Income tax (expense) benefit $ (178 ) 77 Reclassifications, net of income taxes Post-retirement unfunded health benefit: Amortization of actuarial gains $ 74 124 Salaries and other personnel expense (29 ) (48 ) Income tax (expense) benefit $ 45 76 Reclassifications, net of income taxes Reclassifications out of Accumulated Other Comprehensive Income (Loss) Details About Accumulated Other Comprehensive Income (Loss) Components Amount Reclassified from Accumulated Other Comprehensive Income (Loss) Affected Line Item in the Statement Where Net Income is Presented For the Three Months Ended September 30, 2017 2016 Net unrealized gains (losses) on cash flow hedges: Amortization of deferred losses $ — (65 ) Interest expense — 25 Income tax (expense) benefit $ — (40 ) Reclassifications, net of income taxes Net unrealized gains on investment securities available for sale: Realized net (loss)gain on sale of securities $ (7,956 ) 59 Investment securities (losses) gains, net 3,063 (23 ) Income tax (expense) benefit $ (4,893 ) 36 Reclassifications, net of income taxes Post-retirement unfunded health benefit: Amortization of actuarial gains $ 34 20 Salaries and other personnel expense (13 ) (8 ) Income tax (expense) benefit $ 21 12 Reclassifications, net of income taxes

Fair Value Accounting (Tables)

Fair Value Accounting (Tables)	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Financial Instruments Measured at Fair Value on Recurring Basis	The following table presents all financial instruments measured at fair value on a recurring basis as of September 30, 2017 and December 31, 2016 , according to the valuation hierarchy included in ASC 820-10. For equity and debt securities, class was determined based on the nature and risks of the investments. Synovus did not have any transfers between levels during the nine and three months ended September 30, 2017 and year ended December 31, 2016 . September 30, 2017 (in thousands) Level 1 Level 2 Level 3 Total Assets and Liabilities at Fair Value Assets Trading securities: Mortgage-backed securities issued by U.S. Government sponsored enterprises — 494 — 494 Collateralized mortgage obligations issued by U.S. Government sponsored enterprises — 10,484 — 10,484 State and municipal securities — 1,101 — 1,101 Other investments — 250 — 250 Total trading securities $ — 12,329 — 12,329 Mortgage loans held for sale — 54,072 — 54,072 Investment securities available for sale: U.S. Treasury securities 83,181 — — 83,181 U.S. Government agency securities — 11,038 — 11,038 Mortgage-backed securities issued by U.S. Government agencies — 127,384 — 127,384 Mortgage-backed securities issued by U.S. Government sponsored enterprises — 2,651,852 — 2,651,852 Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises — 931,440 — 931,440 State and municipal securities — 181 — 181 Corporate debt and other securities (1) 3,162 15,287 1,918 20,367 Total investment securities available for sale $ 86,343 3,737,182 1,918 3,825,443 Private equity investments — — 15,671 15,671 Mutual funds held in rabbi trusts 13,439 — — 13,439 GGL/SBA loans servicing asset — — 4,270 4,270 Derivative assets: Interest rate contracts — 14,896 — 14,896 Mortgage derivatives (2) — 974 — 974 Total derivative assets $ — 15,870 — 15,870 Liabilities Trading account liabilities — 7,860 — 7,860 Earnout liability (3) — — 16,000 16,000 Derivative liabilities: Interest rate contracts — 12,369 — 12,369 Mortgage derivatives (2) — 32 — 32 Visa derivative — — 4,693 4,693 Total derivative liabilities $ — 12,401 4,693 17,094 December 31, 2016 (in thousands) Level 1 Level 2 Level 3 Total Assets and Liabilities at Fair Value Assets Trading securities: Mortgage-backed securities issued by U.S. Government agencies — 3,460 — 3,460 Collateralized mortgage obligations issued by U.S. Government sponsored enterprises — 3,438 — 3,438 State and municipal securities — 426 — 426 Other investments 1,890 100 — 1,990 Total trading securities $ 1,890 7,424 — 9,314 Mortgage loans held for sale — 51,545 — 51,545 Investment securities available for sale: U.S. Treasury securities 107,802 — — 107,802 U.S. Government agency securities — 12,993 — 12,993 Mortgage-backed securities issued by U.S. Government agencies — 174,202 — 174,202 Mortgage-backed securities issued by U.S. Government sponsored enterprises — 2,506,340 — 2,506,340 Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises — 890,442 — 890,442 State and municipal securities — 2,794 — 2,794 Equity securities 3,782 — — 3,782 Corporate debt and other securities (1) 3,092 14,952 1,796 19,840 Total investment securities available for sale $ 114,676 3,601,723 1,796 3,718,195 Private equity investments — — 25,493 25,493 Mutual funds held in rabbi trusts 11,479 — — 11,479 Derivative assets: Interest rate contracts — 17,157 — 17,157 Mortgage derivatives (2) — 3,466 — 3,466 Total derivative assets $ — 20,623 — 20,623 Liabilities Earnout liability (3) — — 14,000 14,000 Derivative liabilities: Interest rate contracts — 17,531 — 17,531 Visa derivative — — 5,768 5,768 Total derivative liabilities $ — 17,531 5,768 23,299 (1) Based on an analysis of the nature and risks of these investments, Synovus has determined that presenting these investments as a single asset class is appropriate. (2) Mortgage derivatives consist of customer interest rate lock commitments that relate to the potential origination of mortgage loans, which would be classified as held for sale and forward loan sales commitments with third-party investors. (3) Earnout liability consists of contingent consideration obligation related to the Global One acquisition.
Changes in Fair Value Included in Consolidated Statements of Income	The following table summarizes the difference between the fair value and the unpaid principal balance of mortgage loans held for sale measured at fair value and the changes in fair value of these loans. Mortgage loans held for sale are initially measured at fair value with subsequent changes in fair value recognized in earnings. Changes in fair value are recorded as a component of mortgage banking income in the Consolidated Statements of Income. An immaterial portion of these changes in fair value was attributable to changes in instrument-specific credit risk. Changes in Fair Value Included in Net Income For the Nine Months Ended September 30, For the Three Months Ended September 30, (in thousands) 2017 2016 2017 2016 Mortgage loans held for sale $ 850 1,762 $ (104 ) (87 ) Mortgage Loans Held for Sale (in thousands) As of September 30, 2017 As of December 31, 2016 Fair value $ 54,072 51,545 Unpaid principal balance 52,791 51,114 Fair value less aggregate unpaid principal balance $ 1,281 431
Changes in Level 3 Fair Value Measurements	The table below includes a roll-forward of the amounts on the Consolidated Balance Sheets for the nine and three months ended September 30, 2017 and 2016 (including the change in fair value), for financial instruments of a material nature that are classified by Synovus within Level 3 of the fair value hierarchy and are measured at fair value on a recurring basis. Transfers between fair value levels are recognized at the end of the reporting period in which the associated changes in inputs occur. During the nine and three months ended September 30, 2017 and 2016 , Synovus did not have any transfers between levels in the fair value hierarchy. Nine Months Ended September 30, 2017 (in thousands) Investment Securities Available for Sale Private Equity Investments Visa Derivative Earnout Liability (1) GGL / SBA Loans Servicing Asset (2) Beginning balance, January 1, $ 1,796 25,493 (5,768 ) (14,000 ) — Total (losses) gains realized/unrealized: Included in earnings — (3,193 ) — (3,766 ) (721 ) Unrealized gains (losses) included in other comprehensive income 122 — — — — Additions — — — — 539 Sales and settlements — (6,629 ) 1,075 — — Transfer from amortization method to fair value — — — — 4,452 Measurement period adjustments related to Global One acquisition — — — 1,766 — Ending balance, September 30, $ 1,918 15,671 (4,693 ) (16,000 ) 4,270 Total net (losses) gains for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets/liabilities still held at September 30, $ — (3,193 ) — (3,766 ) (721 ) Three Months Ended September 30, 2017 (in thousands) Investment Securities Available for Sale Private Equity Investments Visa Derivative Earnout Liability (1) GGL / SBA Loans Servicing Asset (2) Beginning balance, July 1, $ 1,927 15,698 (5,053 ) (13,941 ) 4,297 Total (losses) gains realized/unrealized: Included in earnings — (27 ) — (2,059 ) (27 ) Unrealized gains (losses) included in other comprehensive income (9 ) — — — — Additions — — — — — Sales and settlements — — 360 — — Measurement period adjustments related to Global One acquisition — — — — — Ending balance, September 30, $ 1,918 15,671 (4,693 ) (16,000 ) 4,270 Total net (losses) gains for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets/liabilities still held at September 30, $ — (27 ) — (2,059 ) (27 ) (1) Earnout liability consists of contingent consideration obligation related to the Global One acquisition. (2) Effective January 1, 2017, Synovus elected the fair value option for determining the value of the GGL/SBA loans servicing asset. Synovus has retained servicing responsibilities on sold GGL/SBA loans and receives a servicing fee. The servicing asset is established at fair value at the time of the sale based on an analysis of future cash flows that incorporates estimates for discount rates, prepayment speeds, and delinquency rates. The servicing asset is measured at fair value on a quarterly basis with changes in fair value included with the associated servicing fee in other non-interest income. Prior to 2017, Synovus accounted for the GGL/SBA loans servicing asset using the amortization method. Nine Months Ended September 30, 2016 (in thousands) Investment Securities Available for Sale Private Equity Investments Visa Derivative Beginning balance, January 1, $ 1,745 27,148 (1,415 ) Total (losses) gains realized/unrealized: Included in earnings — (527 ) (1,080 ) Unrealized gains (losses) included in other comprehensive income 28 — — Settlements — (629 ) 1,080 Ending balance, September 30, $ 1,773 25,992 (1,415 ) Total net (losses) gains for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets still held at September 30, $ — (527 ) (1,080 ) Three Months Ended September 30, 2016 (in thousands) Investment Securities Available for Sale Private Equity Investments Visa Derivative Beginning balance, July 1, $ 1,625 26,866 (1,415 ) Total (losses) gains realized/unrealized: Included in earnings — (249 ) (360 ) Unrealized gains (losses) included in other comprehensive income 148 — — Settlements — (625 ) 360 Ending balance, September 30, $ 1,773 25,992 (1,415 ) Total net (losses) gains for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets still held at September 30, $ — (249 ) (360 )
Fair Value Inputs, Assets, Quantitative Information	The table below provides an overview of the valuation techniques and significant unobservable inputs used in those techniques to measure financial instruments that are classified within Level 3 of the valuation hierarchy and are measured at fair value on a non-recurring basis. The range of sensitivities that management utilized in its fair value calculations is deemed acceptable in the industry with respect to the identified financial instruments. September 30, 2017 December 31, 2016 Valuation Technique Significant Unobservable Input Range (Weighted Average) (1) Range (Weighted Average) (1) Assets measured at fair value on a non-recurring basis Collateral dependent impaired loans Third-party appraised value of collateral less estimated selling costs Discount to appraised value (2) Estimated selling costs 0% - 60% (43%) 0% - 10% (7%) 0%-52% (25%) 0%-10% (7%) Other loans held for sale Third-party appraised value of collateral less estimated selling costs Discount to appraised value (2) Estimated selling costs 0% - 85% (48%) 0% - 10% (2%) N/A Other real estate Third-party appraised value of real estate less estimated selling costs Discount to appraised value (2) Estimated selling costs 0% - 86% (32%) 0% - 10% (7%) 0%-10% (5%) 0%-10% (7%) Other assets held for sale Third-party appraised value less estimated selling costs or BOV Discount to appraised value (2) Estimated selling costs 15%-46% (22%) 0%-10% (7%) 0%-81% (47%) 0%-10% (7%) (1) The range represents management's estimate of the high and low of the value that would be assigned to a particular input. For assets measured at fair value on a non-recurring basis, the weighted average is the measure of central tendencies; it is not the value that management is using for the asset or liability. (2) Synovus also makes adjustments to the values of the assets listed above for reasons including age of the appraisal, information known by management about the property, such as occupancy rates, changes to the physical condition of the property, and other factors. 3Q17 included certain balance sheet restructuring actions which included discounts to fair value for planned accelerated dispositions of other loans held for sale, other real estate, and other assets held for sale. The table below provides an overview of the valuation techniques and significant unobservable inputs used in those techniques to measure financial instruments that are classified within Level 3 of the valuation hierarchy and are measured at fair value on a recurring basis. September 30, 2017 December 31, 2016 Valuation Technique Significant Unobservable Input Range/Weighted Average Range/Weighted Average Assets and liabilities measured at fair value on a recurring basis Investment Securities Available for Sale - Other Investments: Trust preferred securities Discounted cash flow analysis Credit spread embedded in discount rate 398 bps 442 bps Private equity investments Individual analysis of each investee company Multiple factors, including but not limited to, current operations, financial condition, cash flows, evaluation of business management and financial plans, and recently executed financing transactions related to the investee companies N/A N/A Discount for lack of liquidity (1) N/A 15% GGL/SBA loans servicing asset Discounted cash flow analysis Discount rate Prepayment speeds 12.19% 6.75% N/A Earnout liability Option pricing methods and Monte Carlo simulation Global One Earnout, as defined in merger agreement, for the five years ending October 1, 2021 $11.8 million - $16.7 million $9.3 million - $14.2 million Visa derivative liability Discounted cash flow analysis Estimated timing of resolution of covered litigation, future cumulative deposits to the litigation escrow for settlement of the covered litigation, and estimated future monthly fees payable to the derivative counterparty 1-5 years 1-5 years (1) Represents management's estimate of discount that market participants would require based on the instrument's lack of liquidity.
Assets and Liabilities Measured at Fair Value on Non-Recurring Basis	The following table presents assets measured at fair value on a non-recurring basis as of the dates indicated for which there was a fair value adjustment during the period. September 30, 2017 December 31, 2016 (in thousands) Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Impaired loans * $ — — 3,114 3,114 — — 21,742 21,742 Other loans held for sale — — 31,253 31,253 — — — — Other real estate — — 8,137 8,137 — — 19,305 19,305 Other assets held for sale — — 4,033 4,033 — — 12,083 12,083 * Collateral-dependent impaired loans that were written down to fair value during the period.
Assets Measured at Fair Value on a Nonrecurring Basis	The following table presents fair value adjustments recognized in earnings for the nine and three months ended September 30, 2017 and 2016 for the assets measured at fair value on a non-recurring basis. Nine Months Ended September 30, Three Months Ended September 30, (in thousands) 2017 2016 2017 2016 Impaired loans * $ 1,075 1,329 $ 83 59 Other loans held for sale 25,051 2,096 25,051 2,096 Other real estate 5,165 2,405 5,165 968 Other assets held for sale 1,683 7,532 1,683 907 * Collateral-dependent impaired loans that were written down to fair value during the period.
Carrying and Estimated Fair Values of Financial Instruments Carried on Balance Sheet	The carrying and estimated fair values of financial instruments, as well as the level within the fair value hierarchy, as of September 30, 2017 and December 31, 2016 are as follows: September 30, 2017 (in thousands) Carrying Value Fair Value Level 1 Level 2 Level 3 Financial assets Cash and cash equivalents $ 386,459 386,459 386,459 — — Interest bearing funds with Federal Reserve Bank 1,297,581 1,297,581 1,297,581 — — Interest earning deposits with banks 6,047 6,047 6,047 — — Federal funds sold and securities purchased under resale agreements 48,820 48,820 48,820 — — Trading account assets 12,329 12,329 — 12,329 — Mortgage loans held for sale 54,072 54,072 — 54,072 — Other loans held for sale 31,253 31,253 — — 31,253 Investment securities available for sale 3,825,443 3,825,443 86,343 3,737,182 1,918 Private equity investments 15,671 15,671 — — 15,671 Mutual funds held in rabbi trusts 13,439 13,439 13,439 — — Loans, net of deferred fees and costs 24,487,360 24,193,343 — — 24,193,343 GGL/SBA loans servicing asset 4,270 4,270 — — 4,270 Derivative assets 15,870 15,870 — 15,870 — Financial liabilities Trading account liabilities 7,860 7,860 7,860 Non-interest bearing deposits 7,302,682 7,302,682 — 7,302,682 — Interest bearing deposits 18,883,546 18,891,446 — 18,891,446 — Federal funds purchased, other short-term borrowings and other short-term liabilities 141,539 141,539 141,539 — — Long-term debt 1,882,607 1,929,043 — 1,929,043 — Other liabilities 16,000 16,000 — — 16,000 Derivative liabilities 17,094 17,094 — 12,401 4,693 December 31, 2016 (in thousands) Carrying Value Fair Value Level 1 Level 2 Level 3 Financial assets Cash and cash equivalents $ 395,175 395,175 395,175 — — Interest bearing funds with Federal Reserve Bank 527,090 527,090 527,090 — — Interest earning deposits with banks 18,720 18,720 18,720 — — Federal funds sold and securities purchased under resale agreements 58,060 58,060 58,060 — — Trading account assets 9,314 9,314 1,890 7,424 — Mortgage loans held for sale 51,545 51,545 — 51,545 — Investment securities available for sale 3,718,195 3,718,195 114,676 3,601,723 1,796 Private equity investments 25,493 25,493 — — 25,493 Mutual funds held in rabbi trusts 11,479 11,479 11,479 — — Loans, net of deferred fees and costs 23,856,391 23,709,434 — — 23,709,434 Derivative assets 20,623 20,623 — 20,623 — Financial liabilities Non-interest bearing deposits 7,085,804 7,085,804 — 7,085,804 — Interest bearing deposits 17,562,256 17,560,021 — 17,560,021 — Federal funds purchased, other short-term borrowings and other short-term liabilities 159,699 159,699 159,699 — — Long-term debt 2,160,881 2,217,544 — 2,217,544 — Other liabilities 14,000 14,000 — — 14,000 Derivative liabilities 23,299 23,299 — 17,531 5,768

Derivative Instruments (Tables)

Derivative Instruments (Tables)	9 Months Ended
	Sep. 30, 2017
Summary of Derivative Instruments [Abstract]
Impact of Derivatives on Balance Sheet	The impact of derivative instruments on the Consolidated Balance Sheets at September 30, 2017 and December 31, 2016 is presented below. Fair Value of Derivative Assets Fair Value of Derivative Liabilities (in thousands) Location on Consolidated Balance Sheets September 30, 2017 December 31, 2016 Location on Consolidated Balance Sheets September 30, 2017 December 31, 2016 Derivatives not designated as hedging instruments: Interest rate contracts Other assets $ 14,896 17,157 Other liabilities 12,369 17,531 Mortgage derivatives Other assets 974 3,466 Other liabilities 32 — Visa derivative — — Other liabilities 4,693 5,768 Total derivatives not designated as hedging instruments $ 15,870 20,623 17,094 23,299
Effect of Fair Value Hedges on Consolidated Statements of Income	The pre-tax effect of fair value hedges on the Consolidated Statements of Income for the nine and three months ended September 30, 2017 and 2016 is presented below. Location of Gain (Loss) Recognized in Income Gain (Loss) Recognized in Income (in thousands) Nine Months Ended September 30, Derivatives not designated as hedging instruments 2017 2016 Interest rate contracts (1) Other non-interest income $ (5 ) 39 Mortgage derivatives (2) Mortgage banking income (2,524 ) 189 Total $ (2,529 ) 228 Gain (Loss) Recognized in Income (in thousands) Three Months Ended September 30, Derivatives not designated as hedging instruments Location of Gain (Loss) Recognized in Income 2017 2016 Interest rate contracts (1) Other non-interest income $ (4 ) 5 Mortgage derivatives (2) Mortgage banking income (451 ) 674 Total $ (455 ) 679 (1) Gain (loss) represents net fair value adjustments (including credit related adjustments) for customer swaps and offsetting positions. (2) Gain (loss) represents net fair value adjustments recorded for interest rate lock commitments and commitments to sell mortgage loans to third-party investors.

Net Income Per Common Share (Ta

Net Income Per Common Share (Tables)	9 Months Ended
	Sep. 30, 2017
Earnings Per Share [Abstract]
Schedule of Basic And Diluted Earnings per Share	The following table displays a reconciliation of the information used in calculating basic and diluted earnings per common share for the nine and three months ended September 30, 2017 and 2016 . Nine Months Ended September 30, Three Months Ended September 30, (in thousands, except per share data) 2017 2016 2017 2016 Basic Net Income Per Common Share: Net income available to common shareholders $ 238,190 170,555 $ 95,448 62,686 Weighted average common shares outstanding 121,796 125,076 120,900 122,924 Net income per common share, basic $ 1.96 1.36 $ 0.79 0.51 Diluted Net Income Per Common Share: Net income available to common shareholders $ 238,190 170,555 $ 95,448 62,686 Weighted average common shares outstanding 121,796 125,076 120,900 122,924 Potentially dilutive shares from outstanding equity-based awards and Earnout Payments 832 636 914 680 Weighted average diluted common shares 122,628 125,712 121,814 123,604 Net income per common share, diluted $ 1.94 1.36 $ 0.78 0.51

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Loan Commitments and Letters of Credit	Unfunded lending commitments and letters of credit at September 30, 2017 and December 31, 2016 are presented below. (in thousands) September 30, 2017 December 31, 2016 Letters of credit* $ 152,082 150,948 Commitments to fund commercial real estate, construction, and land development loans 1,309,144 1,394,162 Unused credit card lines 1,170,429 1,103,431 Commitments under home equity lines of credit 1,133,569 1,096,052 Commitments to fund commercial and industrial loans 5,164,553 4,792,834 Other loan commitments 326,672 307,772 Total unfunded lending commitments and letters of credit $ 9,256,449 8,845,199 * Represent the contractual amount net of risk participations of approximately $63 million and $83 million at September 30, 2017 and December 31, 2016, respectively.

Significant Accounting Polici33

Significant Accounting Policies (Details)	3 Months Ended	9 Months Ended
	Sep. 30, 2017USD ($)ATMbranch	Sep. 30, 2017USD ($)ATMbranch	Dec. 31, 2016USD ($)
Basis Of Presentation [Line Items]
Number of branches | branch	249	249
Number of ATMs | ATM	328	328
Share-based compensation, excess tax benefit	$ 211,000	$ 4,700,000
Cash and Cash Equivalents
Basis Of Presentation [Line Items]
Total deposits	0	0	$ 533,000
Cash and cash equivalents	57,700,000	57,700,000	130,000,000
Interest earning deposits with banks	6,000,000	6,000,000	5,600,000
Federal funds sold	$ 45,800,000	$ 45,800,000	$ 56,100,000

Acquisitions (Narrative) (Detai

Acquisitions (Narrative) (Details) - USD ($) $ in Thousands	Sep. 25, 2017	Oct. 01, 2016	Sep. 30, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Brokered deposits			$ 2,463,227	$ 1,378,983
Common stock, shares issued (in shares)			142,525,139	142,025,720
Common stock			$ 142,525	$ 142,026
Existing Borrower Relationships
Business Acquisition [Line Items]
Useful life			11 years
Other intangible assets			$ 9,800
Trade Names
Business Acquisition [Line Items]
Useful life			10 years
Other intangible assets			$ 990
Distribution Network
Business Acquisition [Line Items]
Useful life			8 years
Other intangible assets			$ 525
World's Foremost Bank (WFB)
Business Acquisition [Line Items]
Brokered deposits	$ 1,100,000
Deposits portfolio, weighted average maturity, period	2 years 6 months 11 days
Weighted average rate of deposit, brokered	1.83%
Proceeds from fees	$ 75,000
Global One
Business Acquisition [Line Items]
Consideration transferred		$ 30,000
Common stock, shares issued (in shares)		821,000
Common stock		$ 26,592
Cash paid		$ 3,408
Adjustment in goodwill			2,400
Adjustment in contingent consideration			$ 1,800
Global One | Minimum
Business Acquisition [Line Items]
Potential additional payments based on earnings, period		3 years
Global One | Maximum
Business Acquisition [Line Items]
Potential additional payments based on earnings, period		5 years

Acquisitions (Assets Acquired a

Acquisitions (Assets Acquired and Liabilities Assumed) (Details) - USD ($) $ in Thousands	Oct. 01, 2016	Sep. 30, 2017	Dec. 31, 2016
Assets acquired:
Goodwill		$ 57,315	$ 59,678
Liabilities assumed:
Fair value of common stock issued		142,525	142,026
Long-term debt		$ 1,882,607	$ 2,160,881
Global One
Assets acquired:
Cash and due from banks	$ 9,554
Commercial and industrial loans	357,307
Goodwill	32,884
Other intangible assets	12,500
Other assets	3,681
Total assets acquired	415,926
Liabilities assumed:
Notes payable	358,560
Contingent consideration	12,234
Deferred tax liability, net	3,229
Other liabilities	11,903
Total liabilities assumed	385,926
Consideration paid	30,000
Cash paid	3,408
Fair value of common stock issued	26,592
Loans, unpaid principal balance	356,700
Long-term debt	$ 357,000

Share Repurchase Program (Detai

Share Repurchase Program (Details) - USD ($) $ / shares in Units, shares in Millions	8 Months Ended	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Jan. 17, 2017
Equity [Abstract]
Authorized amount				$ 200,000,000
Value repurchased	$ 135,900,000	$ 135,914,000	$ 263,084,000
Shares repurchased (in shares)	3.2
Shares repurchased, average cost per share (in dollars per share)	$ 42.47

Investment Securities (Summary

Investment Securities (Summary Of Available For Sale Investment Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 3,849,862	$ 3,768,618
Gross Unrealized Gains	9,185	11,114
Gross Unrealized Losses	(33,604)	(61,537)
Fair Value	3,825,443	3,718,195
U.S. Treasury securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	83,550	108,221
Gross Unrealized Gains	0	225
Gross Unrealized Losses	(369)	(644)
Fair Value	83,181	107,802
U.S. Government agency securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	10,772	12,727
Gross Unrealized Gains	266	266
Gross Unrealized Losses	0	0
Fair Value	11,038	12,993
Mortgage-backed securities issued by U.S. Government agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	127,521	174,440
Gross Unrealized Gains	715	1,116
Gross Unrealized Losses	(852)	(1,354)
Fair Value	127,384	174,202
Mortgage-backed securities issued by U.S. Government sponsored enterprises
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,663,959	2,543,495
Gross Unrealized Gains	7,917	5,416
Gross Unrealized Losses	(20,024)	(42,571)
Fair Value	2,651,852	2,506,340
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	943,583	905,789
Gross Unrealized Gains	0	1,214
Gross Unrealized Losses	(12,143)	(16,561)
Fair Value	931,440	890,442
State and municipal securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	180	2,780
Gross Unrealized Gains	1	14
Gross Unrealized Losses	0	0
Fair Value	181	2,794
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		919
Gross Unrealized Gains		2,863
Gross Unrealized Losses		0
Fair Value		3,782
Corporate debt and other securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	20,297	20,247
Gross Unrealized Gains	286	0
Gross Unrealized Losses	(216)	(407)
Fair Value	$ 20,367	$ 19,840

Investment Securities (Narrativ

Investment Securities (Narrative) (Details) $ in Millions	Sep. 30, 2017USD ($)position	Dec. 31, 2016USD ($)
Investments [Abstract]
Pledged to secure deposits | $	$ 1,690	$ 2,040
Investment securities in a loss position for less than twelve months	75
Investment securities in a loss position for twelve months or longer	13

Investment Securities (Schedule

Investment Securities (Schedule Of Unrealized Loss On Investments) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	$ 2,410,751	$ 3,012,769
Less than 12 Months, Unrealized Losses	25,666	60,156
12 Months or Longer, Fair Value	301,668	33,315
12 Months or Longer, Unrealized Losses	7,938	1,381
Total Fair Value, Fair Value	2,712,419	3,046,084
Total Fair Value, Unrealized Losses	33,604	61,537
U.S. Treasury securities
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	64,351	64,023
Less than 12 Months, Unrealized Losses	369	644
12 Months or Longer, Fair Value	0	0
12 Months or Longer, Unrealized Losses	0	0
Total Fair Value, Fair Value	64,351	64,023
Total Fair Value, Unrealized Losses	369	644
Mortgage-backed securities issued by U.S. Government agencies
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	80,303	128,121
Less than 12 Months, Unrealized Losses	552	1,240
12 Months or Longer, Fair Value	7,636	3,626
12 Months or Longer, Unrealized Losses	300	114
Total Fair Value, Fair Value	87,939	131,747
Total Fair Value, Unrealized Losses	852	1,354
Mortgage-backed securities issued by U.S. Government sponsored enterprises
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	1,696,906	2,123,181
Less than 12 Months, Unrealized Losses	19,128	42,571
12 Months or Longer, Fair Value	48,596	0
12 Months or Longer, Unrealized Losses	896	0
Total Fair Value, Fair Value	1,745,502	2,123,181
Total Fair Value, Unrealized Losses	20,024	42,571
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	569,191	682,492
Less than 12 Months, Unrealized Losses	5,617	15,653
12 Months or Longer, Fair Value	240,355	24,801
12 Months or Longer, Unrealized Losses	6,526	908
Total Fair Value, Fair Value	809,546	707,293
Total Fair Value, Unrealized Losses	12,143	16,561
Corporate debt and other securities
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	0	14,952
Less than 12 Months, Unrealized Losses	0	48
12 Months or Longer, Fair Value	5,081	4,888
12 Months or Longer, Unrealized Losses	216	359
Total Fair Value, Fair Value	5,081	19,840
Total Fair Value, Unrealized Losses	$ 216	$ 407

Investment Securities (Amortize

Investment Securities (Amortized Cost And Estimated Fair Value By Contractual Maturity Of Investment Securities Available For Sale) (Details) $ in Thousands	Sep. 30, 2017USD ($)
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	$ 21,385
1 to 5 Years, Amortized Cost	73,172
5 to 10 Years, Amortized Cost	517,125
More Than 10 years, Amortized Cost	3,234,883
No Stated Maturity, Amortized Cost	3,297
Total, Amortized Cost	3,849,862
Within One Year, Fair Value	21,441
1 to 5 Years, Fair Value	73,007
5 to 10 Years, Fair Value	515,850
More Than 10 years, Fair Value	3,211,983
No Stated Maturity, Fair Value	3,162
Total, Fair Value	3,825,443
U.S. Treasury securities
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	18,830
1 to 5 Years, Amortized Cost	64,720
5 to 10 Years, Amortized Cost	0
More Than 10 years, Amortized Cost	0
No Stated Maturity, Amortized Cost	0
Total, Amortized Cost	83,550
Within One Year, Fair Value	18,830
1 to 5 Years, Fair Value	64,351
5 to 10 Years, Fair Value	0
More Than 10 years, Fair Value	0
No Stated Maturity, Fair Value	0
Total, Fair Value	83,181
U.S. Government agency securities
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	2,331
1 to 5 Years, Amortized Cost	6,437
5 to 10 Years, Amortized Cost	2,004
More Than 10 years, Amortized Cost	0
No Stated Maturity, Amortized Cost	0
Total, Amortized Cost	10,772
Within One Year, Fair Value	2,385
1 to 5 Years, Fair Value	6,529
5 to 10 Years, Fair Value	2,124
More Than 10 years, Fair Value	0
No Stated Maturity, Fair Value	0
Total, Fair Value	11,038
Mortgage-backed securities issued by U.S. Government agencies
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	0
1 to 5 Years, Amortized Cost	0
5 to 10 Years, Amortized Cost	32,956
More Than 10 years, Amortized Cost	94,565
No Stated Maturity, Amortized Cost	0
Total, Amortized Cost	127,521
Within One Year, Fair Value	0
1 to 5 Years, Fair Value	0
5 to 10 Years, Fair Value	33,073
More Than 10 years, Fair Value	94,311
No Stated Maturity, Fair Value	0
Total, Fair Value	127,384
Mortgage-backed securities issued by U.S. Government sponsored enterprises
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	44
1 to 5 Years, Amortized Cost	2,015
5 to 10 Years, Amortized Cost	446,255
More Than 10 years, Amortized Cost	2,215,645
No Stated Maturity, Amortized Cost	0
Total, Amortized Cost	2,663,959
Within One Year, Fair Value	45
1 to 5 Years, Fair Value	2,127
5 to 10 Years, Fair Value	444,701
More Than 10 years, Fair Value	2,204,979
No Stated Maturity, Fair Value	0
Total, Fair Value	2,651,852
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	0
1 to 5 Years, Amortized Cost	0
5 to 10 Years, Amortized Cost	20,910
More Than 10 years, Amortized Cost	922,673
No Stated Maturity, Amortized Cost	0
Total, Amortized Cost	943,583
Within One Year, Fair Value	0
1 to 5 Years, Fair Value	0
5 to 10 Years, Fair Value	20,666
More Than 10 years, Fair Value	910,774
No Stated Maturity, Fair Value	0
Total, Fair Value	931,440
State and municipal securities
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	180
1 to 5 Years, Amortized Cost	0
5 to 10 Years, Amortized Cost	0
More Than 10 years, Amortized Cost	0
No Stated Maturity, Amortized Cost	0
Total, Amortized Cost	180
Within One Year, Fair Value	181
1 to 5 Years, Fair Value	0
5 to 10 Years, Fair Value	0
More Than 10 years, Fair Value	0
No Stated Maturity, Fair Value	0
Total, Fair Value	181
Corporate debt and other securities
Schedule of Available-for-sale Securities [Line Items]
Within One year, Amortized Cost	0
1 to 5 Years, Amortized Cost	0
5 to 10 Years, Amortized Cost	15,000
More Than 10 years, Amortized Cost	2,000
No Stated Maturity, Amortized Cost	3,297
Total, Amortized Cost	20,297
Within One Year, Fair Value	0
1 to 5 Years, Fair Value	0
5 to 10 Years, Fair Value	15,286
More Than 10 years, Fair Value	1,919
No Stated Maturity, Fair Value	3,162
Total, Fair Value	$ 20,367

Investment Securities (Summar41

Investment Securities (Summary Of Sales Transactions In The Investment Securities Available For Sale Portfolio) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Investments [Abstract]
Proceeds from sales of investment securities available for sale	$ 473,912	$ 353,215	$ 812,293	$ 596,824
Gross realized gains on sales	0	1,635	7,942	2,590
Gross realized losses on sales	(7,956)	(1,576)	(8,231)	(2,464)
Investment securities (losses) gains, net	$ (7,956)	$ 59	$ (289)	$ 126

Restructuring Charges (Schedule

Restructuring Charges (Schedule Of Restructuring And Related Costs) (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2017	Mar. 31, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Restructuring Charges [Abstract]
Severance charges	$ (24)	$ 6,400	$ 0	$ 6,428	$ 0
Asset impairment charges	515		1,240	511	8,120
Other charges	28		3	104	105
Total restructuring charges, net	$ 519		$ 1,243	$ 7,043	$ 8,225

Restructuring Charges (Narrativ

Restructuring Charges (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2017	Mar. 31, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 519		$ 1,243	$ 7,043	$ 8,225
Severance charges	(24)	$ 6,400	0	6,428	0
Special termination benefits		$ 6,200
Severance benefits	1,200			1,200
Asset impairment charges	515		$ 1,240	$ 511	8,120
Held-for-sale
Restructuring Cost and Reserve [Line Items]
Asset impairment charges	$ 515
Corporate real estate optimization activities
Restructuring Cost and Reserve [Line Items]
Restructuring charges					4,800
Facility closing
Restructuring Cost and Reserve [Line Items]
Restructuring charges					$ 3,300

Restructuring Charges (Restruct

Restructuring Charges (Restructuring Reserve) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Restructuring Reserve [Roll Forward]
Beginning balance	$ 7,261	$ 4,968	$ 4,049	$ 6,617
Accruals for voluntary and involuntary termination benefits	(24)	(25)	6,428	6
Payments	(2,604)	(555)	(5,844)	(2,235)
Ending balance	4,633	4,388	4,633	4,388
Severance Charges
Restructuring Reserve [Roll Forward]
Beginning balance	3,731	593	81	1,930
Accruals for voluntary and involuntary termination benefits	(24)	0	6,428	0
Payments	(2,502)	(365)	(5,304)	(1,702)
Ending balance	1,205	228	1,205	228
Lease Termination Charges
Restructuring Reserve [Roll Forward]
Beginning balance	3,530	4,375	3,968	4,687
Accruals for voluntary and involuntary termination benefits	0	(25)	0	6
Payments	(102)	(190)	(540)	(533)
Ending balance	$ 3,428	$ 4,160	$ 3,428	$ 4,160

Loans and Allowance for Loan 45

Loans and Allowance for Loan Losses (Schedule Of Current, Accruing Past Due And Nonaccrual Loans) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	$ 24,328,947	$ 23,663,898
Accruing 30-89 Days Past Due	79,168	61,971
Accruing 90 Days or Greater Past Due	5,685	3,135
Total Accruing Past Due	84,853	65,106
Non-accrual	97,838	153,378
Total loans	24,511,638	23,882,382	$ 23,289,083
Deferred fees and costs, net	24,300	26,000	$ 26,200
Total commercial real estate
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	7,198,401	7,333,053
Accruing 30-89 Days Past Due	15,774	9,037
Accruing 90 Days or Greater Past Due	1,047	161
Total Accruing Past Due	16,821	9,198
Non-accrual	11,702	30,615
Total loans	7,226,924	7,372,866
Total commercial real estate | Investment properties
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	5,919,393	5,861,198
Accruing 30-89 Days Past Due	3,454	2,795
Accruing 90 Days or Greater Past Due	186	0
Total Accruing Past Due	3,640	2,795
Non-accrual	2,063	5,268
Total loans	5,925,096	5,869,261
Total commercial real estate | 1-4 family properties
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	784,520	873,231
Accruing 30-89 Days Past Due	6,588	4,801
Accruing 90 Days or Greater Past Due	796	161
Total Accruing Past Due	7,384	4,962
Non-accrual	2,712	9,114
Total loans	794,616	887,307
Total commercial real estate | Land and development
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	494,488	598,624
Accruing 30-89 Days Past Due	5,732	1,441
Accruing 90 Days or Greater Past Due	65	0
Total Accruing Past Due	5,797	1,441
Non-accrual	6,927	16,233
Total loans	507,212	616,298
Total commercial and industrial
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	11,622,473	11,441,055
Accruing 30-89 Days Past Due	39,596	27,455
Accruing 90 Days or Greater Past Due	2,974	964
Total Accruing Past Due	42,570	28,419
Non-accrual	62,099	75,577
Total loans	11,727,142	11,545,051
Total commercial and industrial | Commercial, financial and agricultural
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	6,871,204	6,839,699
Accruing 30-89 Days Past Due	30,010	9,542
Accruing 90 Days or Greater Past Due	2,356	720
Total Accruing Past Due	32,366	10,262
Non-accrual	58,139	59,074
Total loans	6,961,709	6,909,035
Total commercial and industrial | Owner-occupied
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	4,751,269	4,601,356
Accruing 30-89 Days Past Due	9,586	17,913
Accruing 90 Days or Greater Past Due	618	244
Total Accruing Past Due	10,204	18,157
Non-accrual	3,960	16,503
Total loans	4,765,433	4,636,016
Total consumer
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	5,508,073	4,889,790
Accruing 30-89 Days Past Due	23,798	25,479
Accruing 90 Days or Greater Past Due	1,664	2,010
Total Accruing Past Due	25,462	27,489
Non-accrual	24,037	47,186
Total loans	5,557,572	4,964,465
Total consumer | Home equity lines
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	1,505,556	1,585,228
Accruing 30-89 Days Past Due	7,535	10,013
Accruing 90 Days or Greater Past Due	160	473
Total Accruing Past Due	7,695	10,486
Non-accrual	15,638	21,551
Total loans	1,528,889	1,617,265
Total consumer | Consumer mortgages
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	2,545,986	2,265,966
Accruing 30-89 Days Past Due	5,225	7,876
Accruing 90 Days or Greater Past Due	137	81
Total Accruing Past Due	5,362	7,957
Non-accrual	6,332	22,681
Total loans	2,557,680	2,296,604
Total consumer | Credit cards
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	222,176	229,177
Accruing 30-89 Days Past Due	2,312	1,819
Accruing 90 Days or Greater Past Due	1,237	1,417
Total Accruing Past Due	3,549	3,236
Non-accrual	0	0
Total loans	225,725	232,413
Total consumer | Other consumer loans
Valuation and Qualifying Accounts Disclosure [Line Items]
Current	1,234,355	809,419
Accruing 30-89 Days Past Due	8,726	5,771
Accruing 90 Days or Greater Past Due	130	39
Total Accruing Past Due	8,856	5,810
Non-accrual	2,067	2,954
Total loans	$ 1,245,278	$ 818,183

Loans and Allowance for Loan 46

Loans and Allowance for Loan Losses (Narrative) (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017USD ($)Contract	Sep. 30, 2016USD ($)Contract	Sep. 30, 2017USD ($)Contract	Sep. 30, 2016USD ($)Contract	Dec. 31, 2016USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Average recorded investment in impaired loans	$ 218,682,000	$ 263,000,000	$ 228,922,000	$ 281,200,000	$ 274,515,000
Interest income recognized	1,711,000	0	5,234,000	0	8,196,000
Interest income recognized for accruing TDRs		2,100,000		6,100,000
Non-accrual status	$ 37,600,000		37,600,000		53,700,000
Number of contracts | Contract	3
Post-default balance for modifications classified as TDRs	$ 292,000
Provision for loan losses	$ 39,686,000	$ 5,671,000	$ 58,620,000	$ 21,741,000
Troubled Debt Restructurings That Subsequently Defaulted
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of contracts | Contract	1	1	4	2
Post-default balance for modifications classified as TDRs	$ 206,000	$ 89,000	$ 498,000	$ 181,000
Accruing TDRs With Modifications And Renewals Completed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing troubled debt restructuring	$ 166,900,000		166,900,000
Provision for loan losses			$ 8,500,000		9,800,000
Substandard
Accounts, Notes, Loans and Financing Receivable [Line Items]
Retail loan substandard period (in days)			90 days
Loss And Charged Off
Accounts, Notes, Loans and Financing Receivable [Line Items]
Retail loans downgraded to loss (in days)			120 days
Accruing TDRs With Modifications And Renewals Completed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accruing troubled debt restructuring					$ 195,800,000
Accruing TDRs With Modifications And Renewals Completed | Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial-type impaired loans			$ 1,000,000

Loans and Allowance for Loan 47

Loans and Allowance for Loan Losses (Loan Portfolio Credit Exposure) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Financing Receivable, Recorded Investment [Line Items]
Total loans	$ 24,511,638	$ 23,882,382	$ 23,289,083
Accrual substandard loans	224,500	256,600
Deferred fees and costs, net	$ 24,300	26,000	$ 26,200
Maximum
Financing Receivable, Recorded Investment [Line Items]
Allowance for loan losses, percent of loan amount	50.00%
Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	$ 23,913,138	23,147,814
Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	276,146	324,593
Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	313,890	387,117
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	5,510	19,337
Loss
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,954	3,521
Total commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Total loans	7,226,924	7,372,866
Total commercial real estate | Investment properties
Financing Receivable, Recorded Investment [Line Items]
Total loans	5,925,096	5,869,261
Total commercial real estate | 1-4 family properties
Financing Receivable, Recorded Investment [Line Items]
Total loans	794,616	887,307
Total commercial real estate | Land and development
Financing Receivable, Recorded Investment [Line Items]
Total loans	507,212	616,298
Total commercial real estate | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	7,055,708	7,142,682
Total commercial real estate | Pass | Investment properties
Financing Receivable, Recorded Investment [Line Items]
Total loans	5,847,902	5,794,626
Total commercial real estate | Pass | 1-4 family properties
Financing Receivable, Recorded Investment [Line Items]
Total loans	756,665	826,311
Total commercial real estate | Pass | Land and development
Financing Receivable, Recorded Investment [Line Items]
Total loans	451,141	521,745
Total commercial real estate | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	117,232	137,469
Total commercial real estate | Special Mention | Investment properties
Financing Receivable, Recorded Investment [Line Items]
Total loans	60,423	43,336
Total commercial real estate | Special Mention | 1-4 family properties
Financing Receivable, Recorded Investment [Line Items]
Total loans	20,286	33,928
Total commercial real estate | Special Mention | Land and development
Financing Receivable, Recorded Investment [Line Items]
Total loans	36,523	60,205
Total commercial real estate | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	50,628	85,450
Total commercial real estate | Substandard | Investment properties
Financing Receivable, Recorded Investment [Line Items]
Total loans	16,771	31,299
Total commercial real estate | Substandard | 1-4 family properties
Financing Receivable, Recorded Investment [Line Items]
Total loans	17,438	26,790
Total commercial real estate | Substandard | Land and development
Financing Receivable, Recorded Investment [Line Items]
Total loans	16,419	27,361
Total commercial real estate | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	3,356	7,265
Total commercial real estate | Doubtful | Investment properties
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Total commercial real estate | Doubtful | 1-4 family properties
Financing Receivable, Recorded Investment [Line Items]
Total loans	227	278
Total commercial real estate | Doubtful | Land and development
Financing Receivable, Recorded Investment [Line Items]
Total loans	3,129	6,987
Total commercial real estate | Loss
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Total commercial real estate | Loss | Investment properties
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Total commercial real estate | Loss | 1-4 family properties
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Total commercial real estate | Loss | Land and development
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Total commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Total loans	11,727,142	11,545,051
Total commercial and industrial | Commercial, financial and agricultural
Financing Receivable, Recorded Investment [Line Items]
Total loans	6,961,709	6,909,035
Total commercial and industrial | Owner-occupied
Financing Receivable, Recorded Investment [Line Items]
Total loans	4,765,433	4,636,016
Total commercial and industrial | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	11,337,735	11,098,176
Total commercial and industrial | Pass | Commercial, financial and agricultural
Financing Receivable, Recorded Investment [Line Items]
Total loans	6,704,805	6,635,756
Total commercial and industrial | Pass | Owner-occupied
Financing Receivable, Recorded Investment [Line Items]
Total loans	4,632,930	4,462,420
Total commercial and industrial | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	158,914	187,124
Total commercial and industrial | Special Mention | Commercial, financial and agricultural
Financing Receivable, Recorded Investment [Line Items]
Total loans	106,117	126,268
Total commercial and industrial | Special Mention | Owner-occupied
Financing Receivable, Recorded Investment [Line Items]
Total loans	52,797	60,856
Total commercial and industrial | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	229,089	251,755
Total commercial and industrial | Substandard | Commercial, financial and agricultural
Financing Receivable, Recorded Investment [Line Items]
Total loans	149,456	140,425
Total commercial and industrial | Substandard | Owner-occupied
Financing Receivable, Recorded Investment [Line Items]
Total loans	79,633	111,330
Total commercial and industrial | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,323	7,855
Total commercial and industrial | Doubtful | Commercial, financial and agricultural
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,250	6,445
Total commercial and industrial | Doubtful | Owner-occupied
Financing Receivable, Recorded Investment [Line Items]
Total loans	73	1,410
Total commercial and industrial | Loss
Financing Receivable, Recorded Investment [Line Items]
Total loans	81	141
Total commercial and industrial | Loss | Commercial, financial and agricultural
Financing Receivable, Recorded Investment [Line Items]
Total loans	81	141
Total commercial and industrial | Loss | Owner-occupied
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Total consumer
Financing Receivable, Recorded Investment [Line Items]
Total loans	5,557,572	4,964,465
Total consumer | Home equity lines
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,528,889	1,617,265
Total consumer | Consumer mortgages
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,557,680	2,296,604
Total consumer | Credit cards
Financing Receivable, Recorded Investment [Line Items]
Total loans	225,725	232,413
Total consumer | Other consumer loans
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,245,278	818,183
Total consumer | Pass
Financing Receivable, Recorded Investment [Line Items]
Total loans	5,519,695	4,906,956
Total consumer | Pass | Home equity lines
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,505,724	1,589,199
Total consumer | Pass | Consumer mortgages
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,547,272	2,271,916
Total consumer | Pass | Credit cards
Financing Receivable, Recorded Investment [Line Items]
Total loans	224,488	230,997
Total consumer | Pass | Other consumer loans
Financing Receivable, Recorded Investment [Line Items]
Total loans	1,242,211	814,844
Total consumer | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Total consumer | Special Mention | Home equity lines
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Total consumer | Special Mention | Consumer mortgages
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Total consumer | Special Mention | Credit cards
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Total consumer | Special Mention | Other consumer loans
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Total consumer | Substandard
Financing Receivable, Recorded Investment [Line Items]
Total loans	34,173	49,912
Total consumer | Substandard | Home equity lines
Financing Receivable, Recorded Investment [Line Items]
Total loans	20,771	22,774
Total consumer | Substandard | Consumer mortgages
Financing Receivable, Recorded Investment [Line Items]
Total loans	10,125	23,268
Total consumer | Substandard | Credit cards
Financing Receivable, Recorded Investment [Line Items]
Total loans	523	637
Total consumer | Substandard | Other consumer loans
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,754	3,233
Total consumer | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Total loans	831	4,217
Total consumer | Doubtful | Home equity lines
Financing Receivable, Recorded Investment [Line Items]
Total loans	355	2,892
Total consumer | Doubtful | Consumer mortgages
Financing Receivable, Recorded Investment [Line Items]
Total loans	177	1,283
Total consumer | Doubtful | Credit cards
Financing Receivable, Recorded Investment [Line Items]
Total loans	0	0
Total consumer | Doubtful | Other consumer loans
Financing Receivable, Recorded Investment [Line Items]
Total loans	299	42
Total consumer | Loss
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,873	3,380
Total consumer | Loss | Home equity lines
Financing Receivable, Recorded Investment [Line Items]
Total loans	2,039	2,400
Total consumer | Loss | Consumer mortgages
Financing Receivable, Recorded Investment [Line Items]
Total loans	106	137
Total consumer | Loss | Credit cards
Financing Receivable, Recorded Investment [Line Items]
Total loans	714	779
Total consumer | Loss | Other consumer loans
Financing Receivable, Recorded Investment [Line Items]
Total loans	$ 14	$ 64

Loans and Allowance for Loan 48

Loans and Allowance for Loan Losses (Schedule Of Allowances For Loan Losses And Recorded Investment In Loans) (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Allowance for loan losses:
Beginning balance, allowance	$ 248,095,000	$ 255,076,000	$ 251,758,000	$ 252,496,000	$ 252,496,000
Charge-offs	(44,351,000)	(13,984,000)	(76,749,000)	(41,070,000)
Recoveries	6,253,000	7,054,000	16,054,000	20,650,000
Provision for loan losses	39,686,000	5,671,000	58,620,000	21,741,000
Ending balance, allowance	249,683,000	253,817,000	249,683,000	253,817,000	251,758,000
Ending balance: individually evaluated for impairment, allowance	12,251,000	24,264,000	12,251,000	24,264,000
Ending balance: collectively evaluated for impairment, allowance	237,432,000	229,553,000	237,432,000	229,553,000
Total loans	24,511,638,000	23,289,083,000	24,511,638,000	23,289,083,000	23,882,382,000
Ending balance: individually evaluated for impairment, loans	204,475,000	259,099,000	204,475,000	259,099,000
Ending balance: collectively evaluated for impairment, loans	24,307,163,000	23,029,984,000	24,307,163,000	23,029,984,000
Purchased credit-impaired loans	0	0	0	0
Allowance for purchased credit-impaired loans	0	0	0	0
Deferred fees and costs, net	24,300,000	26,200,000	24,300,000	26,200,000	26,000,000
Commercial Real Estate
Allowance for loan losses:
Beginning balance, allowance	77,527,000	79,359,000	81,816,000	87,133,000	87,133,000
Charge-offs	(8,129,000)	(4,084,000)	(11,336,000)	(13,361,000)
Recoveries	2,543,000	4,237,000	6,191,000	10,927,000
Provision for loan losses	6,019,000	1,590,000	1,289,000	(3,597,000)
Ending balance, allowance	77,960,000	81,102,000	77,960,000	81,102,000	81,816,000
Ending balance: individually evaluated for impairment, allowance	4,108,000	11,066,000	4,108,000	11,066,000
Ending balance: collectively evaluated for impairment, allowance	73,852,000	70,036,000	73,852,000	70,036,000
Total loans	7,226,924,000	7,472,551,000	7,226,924,000	7,472,551,000
Ending balance: individually evaluated for impairment, loans	64,909,000	102,837,000	64,909,000	102,837,000
Ending balance: collectively evaluated for impairment, loans	7,162,015,000	7,369,714,000	7,162,015,000	7,369,714,000
Commercial & Industrial
Allowance for loan losses:
Beginning balance, allowance	123,437,000	129,633,000	125,778,000	122,989,000	122,989,000
Charge-offs	(21,855,000)	(6,437,000)	(41,390,000)	(17,098,000)
Recoveries	1,899,000	1,780,000	5,181,000	6,122,000
Provision for loan losses	23,022,000	5,912,000	36,934,000	18,875,000
Ending balance, allowance	126,503,000	130,888,000	126,503,000	130,888,000	125,778,000
Ending balance: individually evaluated for impairment, allowance	7,360,000	11,474,000	7,360,000	11,474,000
Ending balance: collectively evaluated for impairment, allowance	119,143,000	119,414,000	119,143,000	119,414,000
Total loans	11,727,142,000	11,009,021,000	11,727,142,000	11,009,021,000
Ending balance: individually evaluated for impairment, loans	109,434,000	118,442,000	109,434,000	118,442,000
Ending balance: collectively evaluated for impairment, loans	11,617,708,000	10,890,579,000	11,617,708,000	10,890,579,000
Retail
Allowance for loan losses:
Beginning balance, allowance	47,131,000	46,084,000	44,164,000	42,374,000	42,374,000
Charge-offs	(14,367,000)	(3,463,000)	(24,023,000)	(10,611,000)
Recoveries	1,811,000	1,037,000	4,682,000	3,601,000
Provision for loan losses	10,645,000	(1,831,000)	20,397,000	6,463,000
Ending balance, allowance	45,220,000	41,827,000	45,220,000	41,827,000	$ 44,164,000
Ending balance: individually evaluated for impairment, allowance	783,000	1,724,000	783,000	1,724,000
Ending balance: collectively evaluated for impairment, allowance	44,437,000	40,103,000	44,437,000	40,103,000
Total loans	5,557,572,000	4,807,511,000	5,557,572,000	4,807,511,000
Ending balance: individually evaluated for impairment, loans	30,132,000	37,820,000	30,132,000	37,820,000
Ending balance: collectively evaluated for impairment, loans	$ 5,527,440,000	$ 4,769,691,000	$ 5,527,440,000	$ 4,769,691,000

Loans and Allowance for Loan 49

Loans and Allowance for Loan Losses (Schedule Of Impaired Loans) (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	$ 23,606,000		$ 23,606,000		$ 28,751,000
Recorded Investment, With allowance recorded	180,869,000		180,869,000		220,745,000
Recorded Investment	204,475,000		204,475,000		249,496,000
Unpaid Principal Balance, With no related allowance recorded	29,692,000		29,692,000		40,794,000
Unpaid Principal Balance, With allowance recorded	181,158,000		181,158,000		223,512,000
Unpaid Principal Balance	210,850,000		210,850,000		264,306,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	12,251,000		12,251,000		18,111,000
Related Allowance	12,251,000		12,251,000		18,111,000
Average Recorded Investment, With no related allowance recorded	36,476,000		36,315,000		26,433,000
Average Recorded Investment, With allowance recorded	182,206,000		192,607,000		248,082,000
Average Recorded Investment	218,682,000	$ 263,000,000	228,922,000	$ 281,200,000	274,515,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	1,711,000		5,234,000		8,196,000
Interest Income Recognized	1,711,000	$ 0	5,234,000	$ 0	8,196,000
Total commercial real estate
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	1,741,000		1,741,000		3,490,000
Recorded Investment, With allowance recorded	63,168,000		63,168,000		87,920,000
Recorded Investment	64,909,000		64,909,000		91,410,000
Unpaid Principal Balance, With no related allowance recorded	5,754,000		5,754,000		10,975,000
Unpaid Principal Balance, With allowance recorded	63,224,000		63,224,000		87,926,000
Unpaid Principal Balance	68,978,000		68,978,000		98,901,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	4,108,000		4,108,000		7,916,000
Related Allowance	4,108,000		4,108,000		7,916,000
Average Recorded Investment, With no related allowance recorded	2,164,000		2,622,000		9,803,000
Average Recorded Investment, With allowance recorded	63,035,000		70,702,000		108,091,000
Average Recorded Investment	65,199,000		73,324,000		117,894,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	632,000		1,914,000		3,286,000
Interest Income Recognized	632,000		1,914,000		3,286,000
Total commercial real estate | Investment properties
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	0		0		748,000
Recorded Investment, With allowance recorded	28,651,000		28,651,000		31,489,000
Recorded Investment	28,651,000		28,651,000		32,237,000
Unpaid Principal Balance, With no related allowance recorded	0		0		793,000
Unpaid Principal Balance, With allowance recorded	28,651,000		28,651,000		31,489,000
Unpaid Principal Balance	28,651,000		28,651,000		32,282,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	1,116,000		1,116,000		2,044,000
Related Allowance	1,116,000		1,116,000		2,044,000
Average Recorded Investment, With no related allowance recorded	0		164,000		2,013,000
Average Recorded Investment, With allowance recorded	28,826,000		29,325,000		42,659,000
Average Recorded Investment	28,826,000		29,489,000		44,672,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	306,000		903,000		1,436,000
Interest Income Recognized	306,000		903,000		1,436,000
Total commercial real estate | 1-4 family properties
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	253,000		253,000		643,000
Recorded Investment, With allowance recorded	15,741,000		15,741,000		23,642,000
Recorded Investment	15,994,000		15,994,000		24,285,000
Unpaid Principal Balance, With no related allowance recorded	2,582,000		2,582,000		2,939,000
Unpaid Principal Balance, With allowance recorded	15,741,000		15,741,000		23,649,000
Unpaid Principal Balance	18,323,000		18,323,000		26,588,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	452,000		452,000		769,000
Related Allowance	452,000		452,000		769,000
Average Recorded Investment, With no related allowance recorded	253,000		374,000		1,021,000
Average Recorded Investment, With allowance recorded	15,665,000		16,552,000		39,864,000
Average Recorded Investment	15,918,000		16,926,000		40,885,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	278,000		664,000		855,000
Interest Income Recognized	278,000		664,000		855,000
Total commercial real estate | Land and development
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	1,488,000		1,488,000		2,099,000
Recorded Investment, With allowance recorded	18,776,000		18,776,000		32,789,000
Recorded Investment	20,264,000		20,264,000		34,888,000
Unpaid Principal Balance, With no related allowance recorded	3,172,000		3,172,000		7,243,000
Unpaid Principal Balance, With allowance recorded	18,832,000		18,832,000		32,788,000
Unpaid Principal Balance	22,004,000		22,004,000		40,031,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	2,540,000		2,540,000		5,103,000
Related Allowance	2,540,000		2,540,000		5,103,000
Average Recorded Investment, With no related allowance recorded	1,911,000		2,084,000		6,769,000
Average Recorded Investment, With allowance recorded	18,544,000		24,825,000		25,568,000
Average Recorded Investment	20,455,000		26,909,000		32,337,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	48,000		347,000		995,000
Interest Income Recognized	48,000		347,000		995,000
Total commercial and industrial
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	20,793,000		20,793,000		23,466,000
Recorded Investment, With allowance recorded	88,641,000		88,641,000		97,094,000
Recorded Investment	109,434,000		109,434,000		120,560,000
Unpaid Principal Balance, With no related allowance recorded	22,866,000		22,866,000		27,954,000
Unpaid Principal Balance, With allowance recorded	88,874,000		88,874,000		99,855,000
Unpaid Principal Balance	111,740,000		111,740,000		127,809,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	7,360,000		7,360,000		8,384,000
Related Allowance	7,360,000		7,360,000		8,384,000
Average Recorded Investment, With no related allowance recorded	32,747,000		31,969,000		14,715,000
Average Recorded Investment, With allowance recorded	90,044,000		90,321,000		104,268,000
Average Recorded Investment	122,791,000		122,290,000		118,983,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	716,000		2,177,000		3,161,000
Interest Income Recognized	716,000		2,177,000		3,161,000
Total commercial and industrial | Commercial, financial and agricultural
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	20,696,000		20,696,000		17,958,000
Recorded Investment, With allowance recorded	51,819,000		51,819,000		43,386,000
Recorded Investment	72,515,000		72,515,000		61,344,000
Unpaid Principal Balance, With no related allowance recorded	22,122,000		22,122,000		20,577,000
Unpaid Principal Balance, With allowance recorded	52,019,000		52,019,000		45,913,000
Unpaid Principal Balance	74,141,000		74,141,000		66,490,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	5,730,000		5,730,000		5,687,000
Related Allowance	5,730,000		5,730,000		5,687,000
Average Recorded Investment, With no related allowance recorded	25,583,000		23,094,000		6,321,000
Average Recorded Investment, With allowance recorded	53,040,000		48,694,000		51,968,000
Average Recorded Investment	78,623,000		71,788,000		58,289,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	388,000		1,175,000		1,215,000
Interest Income Recognized	388,000		1,175,000		1,215,000
Total commercial and industrial | Owner-occupied
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	97,000		97,000		5,508,000
Recorded Investment, With allowance recorded	36,822,000		36,822,000		53,708,000
Recorded Investment	36,919,000		36,919,000		59,216,000
Unpaid Principal Balance, With no related allowance recorded	744,000		744,000		7,377,000
Unpaid Principal Balance, With allowance recorded	36,855,000		36,855,000		53,942,000
Unpaid Principal Balance	37,599,000		37,599,000		61,319,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	1,630,000		1,630,000		2,697,000
Related Allowance	1,630,000		1,630,000		2,697,000
Average Recorded Investment, With no related allowance recorded	7,164,000		8,875,000		8,394,000
Average Recorded Investment, With allowance recorded	37,004,000		41,627,000		52,300,000
Average Recorded Investment	44,168,000		50,502,000		60,694,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	328,000		1,002,000		1,946,000
Interest Income Recognized	328,000		1,002,000		1,946,000
Total consumer
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	1,072,000		1,072,000		1,795,000
Recorded Investment, With allowance recorded	29,060,000		29,060,000		35,731,000
Recorded Investment	30,132,000		30,132,000		37,526,000
Unpaid Principal Balance, With no related allowance recorded	1,072,000		1,072,000		1,865,000
Unpaid Principal Balance, With allowance recorded	29,060,000		29,060,000		35,731,000
Unpaid Principal Balance	30,132,000		30,132,000		37,596,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	783,000		783,000		1,811,000
Related Allowance	783,000		783,000		1,811,000
Average Recorded Investment, With no related allowance recorded	1,565,000		1,724,000		1,915,000
Average Recorded Investment, With allowance recorded	29,127,000		31,584,000		35,723,000
Average Recorded Investment	30,692,000		33,308,000		37,638,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	363,000		1,143,000		1,749,000
Interest Income Recognized	363,000		1,143,000		1,749,000
Total consumer | Home equity lines
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	1,072,000		1,072,000		1,051,000
Recorded Investment, With allowance recorded	5,995,000		5,995,000		9,638,000
Recorded Investment	7,067,000		7,067,000		10,689,000
Unpaid Principal Balance, With no related allowance recorded	1,072,000		1,072,000		1,051,000
Unpaid Principal Balance, With allowance recorded	5,995,000		5,995,000		9,638,000
Unpaid Principal Balance	7,067,000		7,067,000		10,689,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	119,000		119,000		971,000
Related Allowance	119,000		119,000		971,000
Average Recorded Investment, With no related allowance recorded	1,069,000		1,063,000		1,045,000
Average Recorded Investment, With allowance recorded	6,534,000		7,807,000		9,668,000
Average Recorded Investment	7,603,000		8,870,000		10,713,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	82,000		265,000		432,000
Interest Income Recognized	82,000		265,000		432,000
Total consumer | Consumer mortgages
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	0		0		744,000
Recorded Investment, With allowance recorded	18,336,000		18,336,000		20,953,000
Recorded Investment	18,336,000		18,336,000		21,697,000
Unpaid Principal Balance, With no related allowance recorded	0		0		814,000
Unpaid Principal Balance, With allowance recorded	18,336,000		18,336,000		20,953,000
Unpaid Principal Balance	18,336,000		18,336,000		21,767,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	382,000		382,000		673,000
Related Allowance	382,000		382,000		673,000
Average Recorded Investment, With no related allowance recorded	496,000		661,000		870,000
Average Recorded Investment, With allowance recorded	18,369,000		19,270,000		20,993,000
Average Recorded Investment	18,865,000		19,931,000		21,863,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	222,000		687,000		1,014,000
Interest Income Recognized	222,000		687,000		1,014,000
Total consumer | Credit cards
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	0		0		0
Recorded Investment, With allowance recorded	0		0		0
Recorded Investment	0		0		0
Unpaid Principal Balance, With no related allowance recorded	0		0		0
Unpaid Principal Balance, With allowance recorded	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	0		0		0
Related Allowance	0		0		0
Average Recorded Investment, With no related allowance recorded	0		0		0
Average Recorded Investment, With allowance recorded	0		0		0
Average Recorded Investment	0		0		0
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	0		0		0
Interest Income Recognized	0		0		0
Total consumer | Other consumer loans
Financing Receivable, Impaired [Line Items]
Recorded Investment, With no related allowance recorded	0		0		0
Recorded Investment, With allowance recorded	4,729,000		4,729,000		5,140,000
Recorded Investment	4,729,000		4,729,000		5,140,000
Unpaid Principal Balance, With no related allowance recorded	0		0		0
Unpaid Principal Balance, With allowance recorded	4,729,000		4,729,000		5,140,000
Unpaid Principal Balance	4,729,000		4,729,000		5,140,000
Related Allowance, With no related allowance recorded	0		0		0
Related Allowance, With allowance recorded	282,000		282,000		167,000
Related Allowance	282,000		282,000		167,000
Average Recorded Investment, With no related allowance recorded	0		0		0
Average Recorded Investment, With allowance recorded	4,224,000		4,507,000		5,062,000
Average Recorded Investment	4,224,000		4,507,000		5,062,000
Interest Income Recognized, With no related allowance recorded	0		0		0
Interest Income Recognized, With allowance recorded	59,000		191,000		303,000
Interest Income Recognized	$ 59,000		$ 191,000		$ 303,000

Loans and Allowance for Loan 50

Loans and Allowance for Loan Losses (Troubled Debt Restructurings) (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2017USD ($)Contract	Sep. 30, 2016USD ($)Contract	Sep. 30, 2017USD ($)Contract	Sep. 30, 2016USD ($)Contract
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	57	22	112	132
Recorded Investment	$ 14,907,000	$ 7,792,000	$ 30,285,000	$ 40,186,000
Net charge-offs	$ 0	$ 0	$ 0
Total commercial real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	8	7	25	40
Recorded Investment	$ 1,881,000	$ 4,127,000	$ 4,619,000	$ 12,024,000
Total commercial real estate | Investment properties
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	0	1	0	4
Recorded Investment	$ 0	$ 3,370,000	$ 0	$ 5,344,000
Total commercial real estate | 1-4 family properties
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	5	4	21	23
Recorded Investment	$ 964,000	$ 260,000	$ 3,567,000	$ 4,914,000
Total commercial real estate | Land and development
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	3	2	4	13
Recorded Investment	$ 917,000	$ 497,000	$ 1,052,000	$ 1,766,000
Total commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	25	6	54	57
Recorded Investment	$ 10,527,000	$ 3,178,000	$ 22,588,000	$ 25,188,000
Total commercial and industrial | Commercial, financial and agricultural
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	22	5	50	50
Recorded Investment	$ 8,809,000	$ 387,000	$ 20,848,000	$ 19,180,000
Total commercial and industrial | Owner-occupied
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	3	1	4	7
Recorded Investment	$ 1,718,000	$ 2,791,000	$ 1,740,000	$ 6,008,000
Total consumer
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	24	9	33	35
Recorded Investment	$ 2,499,000	$ 487,000	$ 3,078,000	$ 2,974,000
Total consumer | Home equity lines
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	0	2	0	5
Recorded Investment	$ 0	$ 123,000	$ 0	$ 347,000
Total consumer | Consumer mortgages
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	7	0	8	6
Recorded Investment	$ 1,429,000	$ 0	$ 1,438,000	$ 405,000
Total consumer | Credit cards
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	0	0	0	0
Recorded Investment	$ 0	$ 0	$ 0	$ 0
Total consumer | Other consumer loans
Financing Receivable, Modifications [Line Items]
Number of Contracts | Contract	17	7	25	24
Recorded Investment	$ 1,070,000	$ 364,000	$ 1,640,000	$ 2,222,000
Principal Forgiveness
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	0
Principal Forgiveness | Total commercial real estate
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	0
Principal Forgiveness | Total commercial real estate | Investment properties
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	0
Principal Forgiveness | Total commercial real estate | 1-4 family properties
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	0
Principal Forgiveness | Total commercial real estate | Land and development
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	0
Principal Forgiveness | Total commercial and industrial
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	0
Principal Forgiveness | Total commercial and industrial | Commercial, financial and agricultural
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	0
Principal Forgiveness | Total commercial and industrial | Owner-occupied
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	0
Principal Forgiveness | Total consumer
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	0
Principal Forgiveness | Total consumer | Home equity lines
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	0
Principal Forgiveness | Total consumer | Consumer mortgages
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	0
Principal Forgiveness | Total consumer | Credit cards
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	0
Principal Forgiveness | Total consumer | Other consumer loans
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	0
Below Market Interest Rate
Financing Receivable, Modifications [Line Items]
Recorded Investment	4,065,000	3,074,000	11,915,000	25,907,000
Below Market Interest Rate | Total commercial real estate
Financing Receivable, Modifications [Line Items]
Recorded Investment	157,000	213,000	2,247,000	5,529,000
Below Market Interest Rate | Total commercial real estate | Investment properties
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	1,826,000
Below Market Interest Rate | Total commercial real estate | 1-4 family properties
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	213,000	2,090,000	3,703,000
Below Market Interest Rate | Total commercial real estate | Land and development
Financing Receivable, Modifications [Line Items]
Recorded Investment	157,000	0	157,000	0
Below Market Interest Rate | Total commercial and industrial
Financing Receivable, Modifications [Line Items]
Recorded Investment	2,978,000	2,791,000	8,738,000	19,406,000
Below Market Interest Rate | Total commercial and industrial | Commercial, financial and agricultural
Financing Receivable, Modifications [Line Items]
Recorded Investment	2,943,000	0	8,703,000	13,948,000
Below Market Interest Rate | Total commercial and industrial | Owner-occupied
Financing Receivable, Modifications [Line Items]
Recorded Investment	35,000	2,791,000	35,000	5,458,000
Below Market Interest Rate | Total consumer
Financing Receivable, Modifications [Line Items]
Recorded Investment	930,000	70,000	930,000	972,000
Below Market Interest Rate | Total consumer | Home equity lines
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	224,000
Below Market Interest Rate | Total consumer | Consumer mortgages
Financing Receivable, Modifications [Line Items]
Recorded Investment	248,000	0	248,000	354,000
Below Market Interest Rate | Total consumer | Credit cards
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	0
Below Market Interest Rate | Total consumer | Other consumer loans
Financing Receivable, Modifications [Line Items]
Recorded Investment	682,000	70,000	682,000	394,000
Term Extensions and/or Other Concessions
Financing Receivable, Modifications [Line Items]
Recorded Investment	10,842,000	4,718,000	18,370,000	14,279,000
Term Extensions and/or Other Concessions | Total commercial real estate
Financing Receivable, Modifications [Line Items]
Recorded Investment	1,724,000	3,914,000	2,372,000	6,495,000
Term Extensions and/or Other Concessions | Total commercial real estate | Investment properties
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	3,370,000	0	3,518,000
Term Extensions and/or Other Concessions | Total commercial real estate | 1-4 family properties
Financing Receivable, Modifications [Line Items]
Recorded Investment	964,000	47,000	1,477,000	1,211,000
Term Extensions and/or Other Concessions | Total commercial real estate | Land and development
Financing Receivable, Modifications [Line Items]
Recorded Investment	760,000	497,000	895,000	1,766,000
Term Extensions and/or Other Concessions | Total commercial and industrial
Financing Receivable, Modifications [Line Items]
Recorded Investment	7,549,000	387,000	13,850,000	5,782,000
Term Extensions and/or Other Concessions | Total commercial and industrial | Commercial, financial and agricultural
Financing Receivable, Modifications [Line Items]
Recorded Investment	5,866,000	387,000	12,145,000	5,232,000
Term Extensions and/or Other Concessions | Total commercial and industrial | Owner-occupied
Financing Receivable, Modifications [Line Items]
Recorded Investment	1,683,000	0	1,705,000	550,000
Term Extensions and/or Other Concessions | Total consumer
Financing Receivable, Modifications [Line Items]
Recorded Investment	1,569,000	417,000	2,148,000	2,002,000
Term Extensions and/or Other Concessions | Total consumer | Home equity lines
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	123,000	0	123,000
Term Extensions and/or Other Concessions | Total consumer | Consumer mortgages
Financing Receivable, Modifications [Line Items]
Recorded Investment	1,181,000	0	1,190,000	51,000
Term Extensions and/or Other Concessions | Total consumer | Credit cards
Financing Receivable, Modifications [Line Items]
Recorded Investment	0	0	0	0
Term Extensions and/or Other Concessions | Total consumer | Other consumer loans
Financing Receivable, Modifications [Line Items]
Recorded Investment	$ 388,000	$ 294,000	$ 958,000	$ 1,828,000

Other Comprehensive Income (L51

Other Comprehensive Income (Loss) (Changes in Accumulated Other Comprehensive Income (Loss) by Component (Net of Income Taxes)) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Balance			$ 2,927,924	$ 3,000,196
Other comprehensive income (loss), Net of Tax Amount	$ 8,269	$ (5,840)	16,063	34,984
Balance	2,997,078	2,906,659	2,997,078	2,906,659
Total
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Balance	(47,865)	11,005	(55,659)	(29,819)
Other comprehensive income (loss) before reclassifications	3,397	(5,832)	15,850	34,890
Amounts reclassified from accumulated other comprehensive income (loss)	4,872	(8)	213	94
Other comprehensive income (loss), Net of Tax Amount	8,269	(5,840)	16,063	34,984
Balance	(39,596)	5,165	(39,596)	5,165
Net unrealized gains (losses) on cash flow hedges
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Balance	(12,137)	(12,297)	(12,217)	(12,504)
Other comprehensive income (loss) before reclassifications	0	0	0	0
Amounts reclassified from accumulated other comprehensive income (loss)	0	40	80	247
Other comprehensive income (loss), Net of Tax Amount	0	40	80	247
Balance	(12,137)	(12,257)	(12,137)	(12,257)
Net unrealized gains (losses) on investment securities available for sale
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Balance	(36,586)	22,459	(44,324)	(18,222)
Other comprehensive income (loss) before reclassifications	3,359	(5,895)	15,812	34,827
Amounts reclassified from accumulated other comprehensive income (loss)	4,893	(36)	178	(77)
Other comprehensive income (loss), Net of Tax Amount	8,252	(5,931)	15,990	34,750
Balance	(28,334)	16,528	(28,334)	16,528
Post-retirement unfunded health benefit
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Balance	858	843	882	907
Other comprehensive income (loss) before reclassifications	38	63	38	63
Amounts reclassified from accumulated other comprehensive income (loss)	(21)	(12)	(45)	(76)
Other comprehensive income (loss), Net of Tax Amount	17	51	(7)	(13)
Balance	$ 875	$ 894	$ 875	$ 894

Other Comprehensive Income (L52

Other Comprehensive Income (Loss) (Narrative) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Class of Stock [Line Items]
Accumulated other comprehensive income (loss)	$ (39,596)	$ (55,659)
Net unrealized gains (losses) on cash flow hedges | Valuation Allowance of Deferred Tax Assets
Class of Stock [Line Items]
Accumulated other comprehensive income (loss)	(12,100)
Net unrealized gains (losses) on investment securities available for sale | Valuation Allowance of Deferred Tax Assets
Class of Stock [Line Items]
Accumulated other comprehensive income (loss)	$ (13,300)

Other Comprehensive Income (L53

Other Comprehensive Income (Loss) (Reclassifications out of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	$ (35,080)	$ (30,547)	$ (101,966)	$ (92,620)
Loss on early extinguishment of debt, net	0	0	0	(4,735)
Income tax (expense) benefit	(54,668)	(37,375)	(130,303)	(102,148)
Investment securities (losses) gains, net	(7,956)	59	(289)	126
Salaries and other personnel expense	(109,675)	(101,945)	(322,079)	(300,364)
Net income available to common shareholders	95,448	62,686	238,190	170,555
Amount Reclassified from Accumulated Other Comprehensive Income (Loss) | Net unrealized gains (losses) on cash flow hedges:
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Interest expense	0	(65)	(130)	(205)
Loss on early extinguishment of debt, net			0	(197)
Income tax (expense) benefit	0	25	50	155
Net income available to common shareholders	0	(40)	(80)	(247)
Amount Reclassified from Accumulated Other Comprehensive Income (Loss) | Net unrealized gains (losses) on investment securities available for sale
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Income tax (expense) benefit	3,063	(23)	111	(49)
Investment securities (losses) gains, net	(7,956)	59	(289)	126
Net income available to common shareholders	(4,893)	36	(178)	77
Amount Reclassified from Accumulated Other Comprehensive Income (Loss) | Post-retirement unfunded health benefit
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Income tax (expense) benefit	(13)	(8)	(29)	(48)
Salaries and other personnel expense	34	20	74	124
Net income available to common shareholders	$ 21	$ 12	$ 45	$ 76

Fair Value Accounting (Financia

Fair Value Accounting (Financial Instruments Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	$ 12,329	$ 9,314
Investment securities available for sale	3,825,443	3,718,195
Mortgage-backed securities issued by U.S. Government sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	2,651,852	2,506,340
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	931,440	890,442
State and municipal securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	181	2,794
Other investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	20,367	19,840
U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	83,181	107,802
Mortgage-backed securities issued by U.S. Government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	127,384	174,202
Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale		3,782
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0	1,890
Investment securities available for sale	86,343	114,676
Private equity investments	0	0
GGL/SBA loans servicing asset	0
Derivative assets	0	0
Earnout liability	0	0
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	12,329	7,424
Investment securities available for sale	3,737,182	3,601,723
Private equity investments	0	0
GGL/SBA loans servicing asset	0
Derivative assets	15,870	20,623
Trading account liabilities	7,860
Earnout liability	0	0
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0	0
Investment securities available for sale	1,918	1,796
Private equity investments	15,671	25,493
GGL/SBA loans servicing asset	4,270
Derivative assets	0	0
Earnout liability	16,000	14,000
Fair Value, Measurements, Recurring Basis
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities		9,314
Mortgage loans held for sale	54,072	51,545
Investment securities available for sale	3,825,443	3,718,195
Private equity investments	15,671	25,493
Mutual funds held in Rabbi Trusts	13,439	11,479
GGL/SBA loans servicing asset	4,270
Derivative assets	15,870	20,623
Trading account liabilities	7,860
Earnout liability	16,000	14,000
Derivative liabilities	17,094	23,299
Fair Value, Measurements, Recurring Basis | Other investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	250	1,990
Fair Value, Measurements, Recurring Basis | Mortgage-backed securities issued by U.S. Government sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	494
Investment securities available for sale	2,651,852	2,506,340
Fair Value, Measurements, Recurring Basis | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	10,484	3,438
Investment securities available for sale	931,440	890,442
Fair Value, Measurements, Recurring Basis | State and municipal securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	1,101	426
Investment securities available for sale	181	2,794
Fair Value, Measurements, Recurring Basis | Other investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	20,367	19,840
Fair Value, Measurements, Recurring Basis | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	83,181	107,802
Fair Value, Measurements, Recurring Basis | U.S. Government agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	11,038	12,993
Fair Value, Measurements, Recurring Basis | Mortgage-backed securities issued by U.S. Government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities		3,460
Investment securities available for sale	127,384	174,202
Fair Value, Measurements, Recurring Basis | Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale		3,782
Fair Value, Measurements, Recurring Basis | Interest rate contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	14,896	17,157
Derivative liabilities	12,369	17,531
Fair Value, Measurements, Recurring Basis | Mortgage derivatives
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	974	3,466
Derivative liabilities	32
Fair Value, Measurements, Recurring Basis | Visa derivative
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	4,693	5,768
Fair Value, Measurements, Recurring Basis | Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0	1,890
Mortgage loans held for sale	0	0
Investment securities available for sale	86,343	114,676
Private equity investments	0	0
Mutual funds held in Rabbi Trusts	13,439	11,479
GGL/SBA loans servicing asset	0
Derivative assets	0	0
Trading account liabilities	0
Earnout liability	0	0
Derivative liabilities	0	0
Fair Value, Measurements, Recurring Basis | Level 1 | Other investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0	1,890
Fair Value, Measurements, Recurring Basis | Level 1 | Mortgage-backed securities issued by U.S. Government sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0
Investment securities available for sale	0	0
Fair Value, Measurements, Recurring Basis | Level 1 | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0	0
Investment securities available for sale	0	0
Fair Value, Measurements, Recurring Basis | Level 1 | State and municipal securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0	0
Investment securities available for sale	0	0
Fair Value, Measurements, Recurring Basis | Level 1 | Other investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	3,162	3,092
Fair Value, Measurements, Recurring Basis | Level 1 | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	83,181	107,802
Fair Value, Measurements, Recurring Basis | Level 1 | U.S. Government agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0	0
Fair Value, Measurements, Recurring Basis | Level 1 | Mortgage-backed securities issued by U.S. Government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities		0
Investment securities available for sale	0	0
Fair Value, Measurements, Recurring Basis | Level 1 | Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale		3,782
Fair Value, Measurements, Recurring Basis | Level 1 | Interest rate contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Derivative liabilities	0	0
Fair Value, Measurements, Recurring Basis | Level 1 | Mortgage derivatives
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Derivative liabilities	0
Fair Value, Measurements, Recurring Basis | Level 1 | Visa derivative
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	0	0
Fair Value, Measurements, Recurring Basis | Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	12,329	7,424
Mortgage loans held for sale	54,072	51,545
Investment securities available for sale	3,737,182	3,601,723
Private equity investments	0	0
Mutual funds held in Rabbi Trusts	0	0
GGL/SBA loans servicing asset	0
Derivative assets	15,870	20,623
Trading account liabilities	7,860
Earnout liability	0	0
Derivative liabilities	12,401	17,531
Fair Value, Measurements, Recurring Basis | Level 2 | Other investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	250	100
Fair Value, Measurements, Recurring Basis | Level 2 | Mortgage-backed securities issued by U.S. Government sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	494
Investment securities available for sale	2,651,852	2,506,340
Fair Value, Measurements, Recurring Basis | Level 2 | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	10,484	3,438
Investment securities available for sale	931,440	890,442
Fair Value, Measurements, Recurring Basis | Level 2 | State and municipal securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	1,101	426
Investment securities available for sale	181	2,794
Fair Value, Measurements, Recurring Basis | Level 2 | Other investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	15,287	14,952
Fair Value, Measurements, Recurring Basis | Level 2 | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0	0
Fair Value, Measurements, Recurring Basis | Level 2 | U.S. Government agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	11,038	12,993
Fair Value, Measurements, Recurring Basis | Level 2 | Mortgage-backed securities issued by U.S. Government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities		3,460
Investment securities available for sale	127,384	174,202
Fair Value, Measurements, Recurring Basis | Level 2 | Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale		0
Fair Value, Measurements, Recurring Basis | Level 2 | Interest rate contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	14,896	17,157
Derivative liabilities	12,369	17,531
Fair Value, Measurements, Recurring Basis | Level 2 | Mortgage derivatives
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	974	3,466
Derivative liabilities	32
Fair Value, Measurements, Recurring Basis | Level 2 | Visa derivative
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	0	0
Fair Value, Measurements, Recurring Basis | Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0	0
Mortgage loans held for sale	0	0
Investment securities available for sale	1,918	1,796
Private equity investments	15,671	25,493
Mutual funds held in Rabbi Trusts	0	0
GGL/SBA loans servicing asset	4,270
Derivative assets	0	0
Trading account liabilities	0
Earnout liability	16,000	14,000
Derivative liabilities	4,693	5,768
Fair Value, Measurements, Recurring Basis | Level 3 | Other investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0	0
Fair Value, Measurements, Recurring Basis | Level 3 | Mortgage-backed securities issued by U.S. Government sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0
Investment securities available for sale	0	0
Fair Value, Measurements, Recurring Basis | Level 3 | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0	0
Investment securities available for sale	0	0
Fair Value, Measurements, Recurring Basis | Level 3 | State and municipal securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0	0
Investment securities available for sale	0	0
Fair Value, Measurements, Recurring Basis | Level 3 | Other investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	1,918	1,796
Fair Value, Measurements, Recurring Basis | Level 3 | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0	0
Fair Value, Measurements, Recurring Basis | Level 3 | U.S. Government agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0	0
Fair Value, Measurements, Recurring Basis | Level 3 | Mortgage-backed securities issued by U.S. Government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities		0
Investment securities available for sale	0	0
Fair Value, Measurements, Recurring Basis | Level 3 | Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale		0
Fair Value, Measurements, Recurring Basis | Level 3 | Interest rate contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Derivative liabilities	0	0
Fair Value, Measurements, Recurring Basis | Level 3 | Mortgage derivatives
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0	0
Derivative liabilities	0
Fair Value, Measurements, Recurring Basis | Level 3 | Visa derivative
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	$ 4,693	$ 5,768

Fair Value Accounting (Changes

Fair Value Accounting (Changes In Fair Value Included In Consolidated Statements Of Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Mortgage loans held for sale	$ (104)	$ (87)	$ 850	$ 1,762
Fair value	54,072		54,072		$ 51,545
Unpaid principal balance	52,791		52,791		51,114
Fair value less aggregate unpaid principal balance	$ 1,281		$ 1,281		$ 431

Fair Value Accounting (Change56

Fair Value Accounting (Changes In Level 3 Fair Value Measurements) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Visa Derivative
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance, January 1,	$ (5,053)	$ (1,415)	$ (5,768)	$ (1,415)
Included in earnings	0	(360)	0	(1,080)
Unrealized gains (losses) included in other comprehensive income	0	0	0	0
Additions	0		0
Sales and settlements	(360)		(1,075)
Settlements		360		1,080
Transfer from amortization method to fair value			0
Measurement period adjustments related to Global One acquisition	0		0
Ending balance, September 30,	(4,693)	(1,415)	(4,693)	(1,415)
Total net (losses) gains for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets/liabilities still held at September 30,	0	(360)	0	(1,080)
Other liabilities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance, January 1,	(13,941)		(14,000)
Included in earnings	(2,059)		(3,766)
Unrealized gains (losses) included in other comprehensive income	0		0
Additions	0		0
Sales and settlements	0		0
Transfer from amortization method to fair value			0
Measurement period adjustments related to Global One acquisition	0		1,766
Ending balance, September 30,	(16,000)		(16,000)
Total net (losses) gains for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets/liabilities still held at September 30,	(2,059)		(3,766)
GGL / SBA Loans Servicing Asset
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance, January 1,	4,297		0
Included in earnings	(27)		(721)
Unrealized gains (losses) included in other comprehensive income	0		0
Additions	0		539
Sales and settlements	0		0
Transfer from amortization method to fair value			4,452
Measurement period adjustments related to Global One acquisition	0		0
Ending balance, September 30,	4,270		4,270
Total net (losses) gains for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets/liabilities still held at September 30,	(27)		(721)
Investment Securities Available for Sale
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance, January 1,	1,927	1,625	1,796	1,745
Included in earnings	0	0	0	0
Unrealized gains (losses) included in other comprehensive income	(9)	148	122	28
Additions	0		0
Sales and settlements	0		0
Settlements		0		0
Transfer from amortization method to fair value			0
Measurement period adjustments related to Global One acquisition	0		0
Ending balance, September 30,	1,918	1,773	1,918	1,773
Total net (losses) gains for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets/liabilities still held at September 30,	0	0	0	0
Private Equity Investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance, January 1,	15,698	26,866	25,493	27,148
Included in earnings	(27)	(249)	(3,193)	(527)
Unrealized gains (losses) included in other comprehensive income	0	0	0	0
Additions	0		0
Sales and settlements	0		6,629
Settlements		(625)		(629)
Transfer from amortization method to fair value			0
Measurement period adjustments related to Global One acquisition	0		0
Ending balance, September 30,	15,671	25,992	15,671	25,992
Total net (losses) gains for the period included in earnings attributable to the change in unrealized gains (losses) relating to assets/liabilities still held at September 30,	$ (27)	$ (249)	$ (3,193)	$ (527)

Fair Value Accounting (Assets A

Fair Value Accounting (Assets And Liabilities Measured At Fair Value On A Non-Recurring Basis) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	$ 204,475	$ 249,496
Other real estate	10,551	22,308
Fair Value, Measurements, Nonrecurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	3,114	21,742
Other loans held for sale	31,253	0
Other real estate	8,137	19,305
Other assets held for sale	4,033	12,083
Fair Value, Measurements, Nonrecurring Basis | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	0	0
Other loans held for sale	0	0
Other real estate	0	0
Other assets held for sale	0	0
Fair Value, Measurements, Nonrecurring Basis | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	0	0
Other loans held for sale	0	0
Other real estate	0	0
Other assets held for sale	0	0
Fair Value, Measurements, Nonrecurring Basis | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	3,114	21,742
Other loans held for sale	31,253	0
Other real estate	8,137	19,305
Other assets held for sale	$ 4,033	$ 12,083

Fair Value Accounting (Assets M

Fair Value Accounting (Assets Measured at Fair Value on Nonrecurring Basis) (Details) - Fair Value, Measurements, Nonrecurring Basis - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Impaired loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value adjustment	$ 83	$ 59	$ 1,075	$ 1,329
Other loans held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value adjustment	25,051	2,096	25,051	2,096
Other real estate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value adjustment	5,165	968	5,165	2,405
Other assets held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, fair value adjustment	$ 1,683	$ 907	$ 1,683	$ 7,532

Fair Value Accounting (Fair Val

Fair Value Accounting (Fair Value Inputs, Assets, Quantitative Information) (Details) - Level 3 - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Fair Value, Measurements, Recurring Basis | Other liabilities | Option pricing methods and Monte Carlo simulation | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings as defined in merger agreement	$ 11.8	$ 9.3
Fair Value, Measurements, Recurring Basis | Other liabilities | Option pricing methods and Monte Carlo simulation | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Earnings as defined in merger agreement	$ 16.7	$ 14.2
Fair Value, Measurements, Recurring Basis | Visa Derivative | Discounted cash flow analysis | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Estimated future monthly fees payable to the derivative counterparty, period	1 year	1 year
Fair Value, Measurements, Recurring Basis | Visa Derivative | Discounted cash flow analysis | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Estimated future monthly fees payable to the derivative counterparty, period	5 years	5 years
Fair Value, Measurements, Recurring Basis | Trust preferred securities | Discounted cash flow analysis
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Credit spread embedded in discount rate	3.98%	4.42%
Fair Value, Measurements, Recurring Basis | Private equity investments | Internal valuation
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount for lack of liquidity		15.00%
Fair Value, Measurements, Recurring Basis | GGL / SBA Loans Servicing Asset | Discounted cash flow analysis
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	12.19%
Prepayment speeds	6.75%
Fair Value, Measurements, Nonrecurring Basis | Collateral dependent impaired loans | Third-party appraised value of collateral less estimated selling costs | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	0.00%	0.00%
Estimated selling costs	0.00%	0.00%
Fair Value, Measurements, Nonrecurring Basis | Collateral dependent impaired loans | Third-party appraised value of collateral less estimated selling costs | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	60.00%	52.00%
Estimated selling costs	10.00%	10.00%
Fair Value, Measurements, Nonrecurring Basis | Collateral dependent impaired loans | Third-party appraised value of collateral less estimated selling costs | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	43.00%	25.00%
Estimated selling costs	7.00%	7.00%
Fair Value, Measurements, Nonrecurring Basis | Other loans held for sale | Third-party appraised value of collateral less estimated selling costs | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	0.00%
Estimated selling costs	0.00%
Fair Value, Measurements, Nonrecurring Basis | Other loans held for sale | Third-party appraised value of collateral less estimated selling costs | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	85.00%
Estimated selling costs	10.00%
Fair Value, Measurements, Nonrecurring Basis | Other loans held for sale | Third-party appraised value of collateral less estimated selling costs | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	48.00%
Estimated selling costs	2.00%
Fair Value, Measurements, Nonrecurring Basis | Other real estate | Third-party appraised value of collateral less estimated selling costs | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	0.00%	0.00%
Estimated selling costs	0.00%	0.00%
Fair Value, Measurements, Nonrecurring Basis | Other real estate | Third-party appraised value of collateral less estimated selling costs | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	86.00%	10.00%
Estimated selling costs	10.00%	10.00%
Fair Value, Measurements, Nonrecurring Basis | Other real estate | Third-party appraised value of collateral less estimated selling costs | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	32.00%	5.00%
Estimated selling costs	7.00%	7.00%
Fair Value, Measurements, Nonrecurring Basis | Other assets held for sale | Third-party appraised value less estimated selling costs or BOV | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	15.00%	0.00%
Estimated selling costs	0.00%	0.00%
Fair Value, Measurements, Nonrecurring Basis | Other assets held for sale | Third-party appraised value less estimated selling costs or BOV | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	46.00%	81.00%
Estimated selling costs	10.00%	10.00%
Fair Value, Measurements, Nonrecurring Basis | Other assets held for sale | Third-party appraised value less estimated selling costs or BOV | Weighted Average
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount to appraised value	22.00%	47.00%
Estimated selling costs	7.00%	7.00%

Fair Value Accounting (Carrying

Fair Value Accounting (Carrying And Estimated Fair Values Of Financial Instruments Carried On Balance Sheet) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Financial assets
Interest bearing funds with Federal Reserve Bank	$ 1,297,581	$ 527,090
Interest earning deposits with banks	6,047	18,720
Federal funds sold and securities purchased under resale agreements	48,820	58,060
Trading account assets	12,329	9,314
Mortgage loans held for sale	54,072	51,545
Other loans held for sale	31,253	0
Investment securities available for sale	3,825,443	3,718,195
Loans, net	24,237,677	23,604,633
Financial liabilities
Non-interest bearing deposits	7,302,682	7,085,804
Federal funds purchased, other short-term borrowings and other short-term liabilities	141,539	159,699
Long-term debt	1,882,607	2,160,881
Level 1
Financial assets
Cash and cash equivalents	386,459	395,175
Interest bearing funds with Federal Reserve Bank	1,297,581	527,090
Interest earning deposits with banks	6,047	18,720
Federal funds sold and securities purchased under resale agreements	48,820	58,060
Trading account assets	0	1,890
Mortgage loans held for sale	0	0
Other loans held for sale	0
Investment securities available for sale	86,343	114,676
Private equity investments	0	0
Mutual funds held in Rabbi Trusts	13,439	11,479
Loans, net	0	0
GGL/SBA loans servicing asset	0
Derivative assets	0	0
Financial liabilities
Non-interest bearing deposits	0	0
Interest bearing deposits	0	0
Federal funds purchased, other short-term borrowings and other short-term liabilities	141,539	159,699
Long-term debt	0	0
Other liabilities	0	0
Derivative liability positions	0	0
Level 2
Financial assets
Cash and cash equivalents	0	0
Interest bearing funds with Federal Reserve Bank	0	0
Interest earning deposits with banks	0	0
Federal funds sold and securities purchased under resale agreements	0	0
Trading account assets	12,329	7,424
Mortgage loans held for sale	54,072	51,545
Other loans held for sale	0
Investment securities available for sale	3,737,182	3,601,723
Private equity investments	0	0
Mutual funds held in Rabbi Trusts	0	0
Loans, net	0	0
GGL/SBA loans servicing asset	0
Derivative assets	15,870	20,623
Financial liabilities
Trading account liabilities	7,860
Non-interest bearing deposits	7,302,682	7,085,804
Interest bearing deposits	18,891,446	17,560,021
Federal funds purchased, other short-term borrowings and other short-term liabilities	0	0
Long-term debt	1,929,043	2,217,544
Other liabilities	0	0
Derivative liability positions	12,401	17,531
Level 3
Financial assets
Cash and cash equivalents	0	0
Interest bearing funds with Federal Reserve Bank	0	0
Interest earning deposits with banks	0	0
Federal funds sold and securities purchased under resale agreements	0	0
Trading account assets	0	0
Mortgage loans held for sale	0	0
Other loans held for sale	31,253
Investment securities available for sale	1,918	1,796
Private equity investments	15,671	25,493
Mutual funds held in Rabbi Trusts	0	0
Loans, net	24,193,343	23,709,434
GGL/SBA loans servicing asset	4,270
Derivative assets	0	0
Financial liabilities
Non-interest bearing deposits	0	0
Interest bearing deposits	0	0
Federal funds purchased, other short-term borrowings and other short-term liabilities	0	0
Long-term debt	0	0
Other liabilities	16,000	14,000
Derivative liability positions	4,693	5,768
Carrying Value
Financial assets
Cash and cash equivalents	386,459	395,175
Interest bearing funds with Federal Reserve Bank	1,297,581	527,090
Interest earning deposits with banks	6,047	18,720
Federal funds sold and securities purchased under resale agreements	48,820	58,060
Trading account assets	12,329	9,314
Mortgage loans held for sale	54,072	51,545
Other loans held for sale	31,253
Investment securities available for sale	3,825,443	3,718,195
Private equity investments	15,671	25,493
Mutual funds held in Rabbi Trusts	13,439	11,479
Loans, net	24,487,360	23,856,391
GGL/SBA loans servicing asset	4,270
Derivative assets	15,870	20,623
Financial liabilities
Trading account liabilities	7,860
Non-interest bearing deposits	7,302,682	7,085,804
Interest bearing deposits	18,883,546	17,562,256
Federal funds purchased, other short-term borrowings and other short-term liabilities	141,539	159,699
Long-term debt	1,882,607	2,160,881
Other liabilities	16,000	14,000
Derivative liability positions	17,094	23,299
Fair Value
Financial assets
Cash and cash equivalents	386,459	395,175
Interest bearing funds with Federal Reserve Bank	1,297,581	527,090
Interest earning deposits with banks	6,047	18,720
Federal funds sold and securities purchased under resale agreements	48,820	58,060
Trading account assets	12,329	9,314
Mortgage loans held for sale	54,072	51,545
Other loans held for sale	31,253
Investment securities available for sale	3,825,443	3,718,195
Private equity investments	15,671	25,493
Mutual funds held in Rabbi Trusts	13,439	11,479
Loans, net	24,193,343	23,709,434
GGL/SBA loans servicing asset	4,270
Derivative assets	15,870	20,623
Financial liabilities
Trading account liabilities	7,860
Non-interest bearing deposits	7,302,682	7,085,804
Interest bearing deposits	18,891,446	17,560,021
Federal funds purchased, other short-term borrowings and other short-term liabilities	141,539	159,699
Long-term debt	1,929,043	2,217,544
Other liabilities	16,000	14,000
Derivative liability positions	$ 17,094	$ 23,299

Derivative Instruments (Narrati

Derivative Instruments (Narrative) (Details) - USD ($)	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Derivative [Line Items]
Remaining unamortized deferred gain (loss) balance of all previously terminated cash flow hedges			$ (130,000)
Remaining deferred gain balance on all previously terminated fair value hedges			873,000
Derivative, fair value	$ 4,700,000		5,800,000
Loss on sale of outstanding commitments	1,900,000	$ 830,000
Collateral requirements	45,800,000
Deferred gains (loss) on discontinuation of cash flow hedge reclassified to earnings	873,000	1,400,000
Reclassification of hedge-related basis adjustment as a reduction to loss on early extinguishment of debt		1,300,000
Fixed Rate Residential Mortgage
Derivative [Line Items]
Commitments to fund fixed-rate mortgage loans	64,300,000		88,200,000
Unrealized gain (loss) on fair value of fixed-rate mortgage loans to customers	(595,000)	$ 1,000,000
Sale of outstanding commitments	83,000,000		$ 126,500,000
Interest Rate Swap
Derivative [Line Items]
Notional amount of interest rate swap contracts	1,540,000,000
Increase in derivative, notional amount	$ 216,900,000

Derivative Instruments (Impact

Derivative Instruments (Impact Of Derivatives On Balance Sheet) (Details) - Derivatives not designated as hedging instruments - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Other assets
Derivative [Line Items]
Fair value of derivative assets	$ 15,870	$ 20,623
Other assets | Interest rate contracts
Derivative [Line Items]
Fair value of derivative assets	14,896	17,157
Other assets | Mortgage derivatives
Derivative [Line Items]
Fair value of derivative assets	974	3,466
Other assets | Visa derivative
Derivative [Line Items]
Fair value of derivative assets	0	0
Other liabilities
Derivative [Line Items]
Fair value of derivative liabilities	17,094	23,299
Other liabilities | Interest rate contracts
Derivative [Line Items]
Fair value of derivative liabilities	12,369	17,531
Other liabilities | Mortgage derivatives
Derivative [Line Items]
Fair value of derivative liabilities	32	0
Other liabilities | Visa derivative
Derivative [Line Items]
Fair value of derivative liabilities	$ 4,693	$ 5,768

Derivative Instruments (Effect

Derivative Instruments (Effect Of Fair Value Hedges On Consolidated Statements Of Income) (Details) - Derivatives not designated as hedging instruments - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Derivative [Line Items]
Gain (Loss) Recognized in Income	$ (455)	$ 679	$ (2,529)	$ 228
Interest rate contracts | Other non-interest income
Derivative [Line Items]
Gain (Loss) Recognized in Income	(4)	5	(5)	39
Mortgage derivatives | Mortgage banking income
Derivative [Line Items]
Gain (Loss) Recognized in Income	$ (451)	$ 674	$ (2,524)	$ 189

Net Income Per Common Share (Sc

Net Income Per Common Share (Schedule Of Basic And Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Basic Earnings (Loss) Per Share
Net income available to common shareholders	$ 95,448	$ 62,686	$ 238,190	$ 170,555
Weighted average common shares outstanding (in shares)	120,900	122,924	121,796	125,076
Net income per common share, basic (in dollars per share)	$ 0.79	$ 0.51	$ 1.96	$ 1.36
Diluted Earnings (Loss) Per Share
Net income available to common shareholders	$ 95,448	$ 62,686	$ 238,190	$ 170,555
Weighted average common shares outstanding (in shares)	120,900	122,924	121,796	125,076
Potentially dilutive shares from outstanding equity-based awards and Earnout Payments (in shares)	914	680	832	636
Weighted average number of diluted common shares (in shares)	121,814	123,604	122,628	125,712
Net income per common share, diluted (in dollars per share)	$ 0.78	$ 0.51	$ 1.94	$ 1.36

Net Income Per Common Share (Na

Net Income Per Common Share (Narrative) (Details) - shares shares in Millions	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Earnings Per Share [Abstract]
Potentially dilutive shares	2.2	2.5

Share-based Compensation (Detai

Share-based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 3.7	$ 3.4	$ 10.6	$ 10.2
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other equity compensation, shares granted (in shares)			0
Options outstanding (in options)	809,000		809,000
Weighted-average exercise price, options (in dollars per share)	$ 17.82		$ 17.82
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)			3 years
Other equity compensation, shares granted (in shares)			235,000
Weighted-average exercise price, shares granted during period (in dollars per share)			$ 41.95
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other equity compensation, shares granted (in shares)			73,000
Weighted-average exercise price, shares granted during period (in dollars per share)			$ 41.95
Market Restricted Stock Units (MRSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)			3 years
Other equity compensation, shares granted (in shares)			73,000
Weighted-average exercise price, shares granted during period (in dollars per share)			$ 41.95
Non-Vested Synovus Shares And Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other equity compensation, non-vested shares outstanding (in shares)	973,000		973,000
Weighted-average exercise price, non-vested shares outstanding (in dollars per share)	$ 32.91		$ 32.91
Minimum | Market Restricted Stock Units (MRSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range based on shareholder return	75.00%		75.00%
Minimum | Performance Share Units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range based on return on average assets (ROAA)	0.00%		0.00%
Maximum | Market Restricted Stock Units (MRSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range based on shareholder return	125.00%		125.00%
Maximum | Performance Share Units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range based on return on average assets (ROAA)	150.00%		150.00%
2013 Omnibus Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equivalents authorized (in shares)	5,700,000		5,700,000
Shares of authorized but unissued common stock reserved for future grants (in shares)	8,600,000		8,600,000
Contractual term (years)			10 years
2013 Omnibus Plan | Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share equivalents ratio (in shares)	1		1
2013 Omnibus Plan | Value Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share equivalents ratio (in shares)	2		2
2013 Omnibus Plan | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)			3 years
2013 Omnibus Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)			5 years

Commitments and Contingencies67

Commitments and Contingencies (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Loss Contingencies [Line Items]
Contractual amount net of risk participations	$ 63,000	$ 83,000
Guarantee obligations
Loss Contingencies [Line Items]
Total unfunded lending commitments and letters of credit	9,256,449	8,845,199
Letters of credit
Loss Contingencies [Line Items]
Total unfunded lending commitments and letters of credit	152,082	150,948
Commitments to fund commercial real estate, construction, and land development loans
Loss Contingencies [Line Items]
Total unfunded lending commitments and letters of credit	1,309,144	1,394,162
Unused credit card lines
Loss Contingencies [Line Items]
Total unfunded lending commitments and letters of credit	1,170,429	1,103,431
Commitments under home equity lines of credit
Loss Contingencies [Line Items]
Total unfunded lending commitments and letters of credit	1,133,569	1,096,052
Commitments to fund commercial and industrial loans
Loss Contingencies [Line Items]
Total unfunded lending commitments and letters of credit	5,164,553	4,792,834
Other loan commitments
Loss Contingencies [Line Items]
Total unfunded lending commitments and letters of credit	$ 326,672	$ 307,772

Legal Proceedings (Details)

Legal Proceedings (Details)	Sep. 30, 2017USD ($)
Minimum
Loss Contingencies [Line Items]
Total unfunded lending commitments and letters of credit	$ 0
Maximum
Loss Contingencies [Line Items]
Total unfunded lending commitments and letters of credit	$ 10,000,000

Subsequent Events (Details)

Subsequent Events (Details) - USD ($)	3 Months Ended			9 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Nov. 01, 2017	Sep. 25, 2017
Subsequent Event [Line Items]
Loss on early extinguishment of debt, net		$ 0	$ 0	$ 0	$ 4,735,000
7.875% Senior Notes due 2019
Subsequent Event [Line Items]
Repurchased face amount							$ 300,000,000
Interest rate							7.875%
7.875% Senior Notes due 2019 | Forecast
Subsequent Event [Line Items]
Loss on early extinguishment of debt, net	$ 24,000,000
3.125% Senior Notes due 2022 | Subsequent Event
Subsequent Event [Line Items]
Interest rate						3.125%
Face amount of debt						$ 300,000,000