Fulton Financial (FULT) 10-Q 6 Nov 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Oct. 31, 2018
Document and Entity Information
Entity Registrant Name	FULTON FINANCIAL CORP
Entity Central Index Key	700,564
Trading Symbol	fult
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		176,096,000

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
ASSETS
Cash and due from banks	$ 90,361	$ 108,291
Interest-bearing deposits with other banks	322,330	293,805
Federal Reserve Bank and Federal Home Loan Bank stock	65,926	60,761
Loans held for sale	27,525	31,530
Available for sale, at estimated fair value	2,008,816
Available for sale investment securities		2,547,956
Held to maturity, at amortized cost	626,597	0
Loans, net of unearned income	15,925,093	15,768,247
Less: Allowance for loan losses	(157,810)	(169,910)
Net Loans	15,767,283	15,598,337
Premises and equipment	231,236	222,802
Accrued interest receivable	58,584	52,910
Goodwill and intangible assets	531,556	531,556
Other assets	634,596	588,957
Total Assets	20,364,810	20,036,905
LIABILITIES
Noninterest-bearing	4,216,064	4,437,294
Interest-bearing	12,032,950	11,360,238
Total Deposits	16,249,014	15,797,532
Short-term borrowings:
Federal funds purchased	50,000	220,000
Other short-term borrowings	435,565	397,524
Total Short-Term Borrowings	485,565	617,524
Accrued interest payable	11,151	9,317
Other liabilities	343,951	344,329
Federal Home Loan Bank advances and other long-term debt	992,115	1,038,346
Total Liabilities	18,081,796	17,807,048
SHAREHOLDERS’ EQUITY
Common stock, $2.50 par value, 600 million shares authorized, 221.7 million shares issued in 2018 and 220.9 million shares issued in 2017	554,208	552,232
Additional paid-in capital	1,487,129	1,478,389
Retained earnings	915,687	821,619
Accumulated other comprehensive loss	(84,640)	(32,974)
Treasury stock, at cost, 45.7 million shares in 2018 and 2017	(589,370)	(589,409)
Total Shareholders’ Equity	2,283,014	2,229,857
Total Liabilities and Shareholders’ Equity	$ 20,364,810	$ 20,036,905

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 2.5	$ 2.5
Common stock, shares authorized (in shares)	600,000,000	600,000,000
Common stock, shares issued (in shares)	221,700,000	220,900,000
Treasury stock, shares (in shares)	45,700,000	45,700,000

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
INTEREST INCOME
Loans, including fees	$ 175,068	$ 155,152	$ 503,029	$ 446,158
Investment securities:
Taxable	13,956	11,423	41,034	34,811
Tax-exempt	3,035	2,920	8,933	8,625
Dividends	0	105	5	343
Loans held for sale	388	243	888	631
Other interest income	1,601	1,667	4,016	3,311
Total Interest Income	194,048	171,510	557,905	493,879
INTEREST EXPENSE
Deposits	23,819	16,023	59,553	40,709
Short-term borrowings	2,002	578	7,079	2,407
Federal Home Loan Bank advances and other long-term debt	8,100	8,100	23,761	24,812
Total Interest Expense	33,921	24,701	90,393	67,928
Net Interest Income	160,127	146,809	467,512	425,951
Provision for credit losses	1,620	5,075	38,707	16,575
Net Interest Income After Provision for Credit Losses	158,507	141,734	428,805	409,376
NON-INTEREST INCOME
Non-interest income before investment securities gains	51,019	47,377	145,965	143,879
Investment securities gains, net	14	4,597	37	7,139
Total Non-Interest Income	51,033	51,974	146,002	151,018
NON-INTEREST EXPENSE
Salaries and employee benefits	76,770	72,894	227,457	216,626
Net occupancy expense	12,578	12,180	38,970	37,159
Data processing and software	10,157	10,301	31,083	28,334
Other outside services	9,122	6,582	24,814	19,836
Amortization of tax credit investments	1,637	3,503	4,911	7,652
Professional fees	3,427	3,388	10,615	9,056
Equipment expense	3,000	3,298	9,968	9,691
FDIC insurance expense	2,814	3,007	8,430	7,431
Taxes, Other	2,707	2,830	7,463	7,730
Marketing	2,692	2,089	7,277	6,309
Other	10,509	12,085	34,431	37,303
Total Non-Interest Expense	135,413	132,157	405,419	387,127
Income Before Income Taxes	74,127	61,551	169,388	173,267
Income taxes	8,494	12,646	19,078	35,515
Net Income	$ 65,633	$ 48,905	$ 150,310	$ 137,752
PER SHARE:
Net Income (Basic) (in dollars per share)	$ 0.37	$ 0.28	$ 0.86	$ 0.79
Net Income (Diluted) (in dollars per share)	0.37	0.28	0.85	0.78
Cash Dividends (in dollars per share)	$ 0.12	$ 0.11	$ 0.36	$ 0.33
Investment management and trust services
NON-INTEREST INCOME
Non-interest income before investment securities gains	$ 13,066	$ 12,157	$ 38,740	$ 36,097
Other service charges and fees
NON-INTEREST INCOME
Non-interest income before investment securities gains	15,433	12,251	40,517	39,030
Service charges on deposit accounts
NON-INTEREST INCOME
Non-interest income before investment securities gains	12,259	13,022	36,491	38,336
Mortgage banking income
NON-INTEREST INCOME
Non-interest income before investment securities gains	4,896	4,805	14,252	15,542
Other
NON-INTEREST INCOME
Non-interest income before investment securities gains	$ 5,365	$ 5,142	$ 15,965	$ 14,874

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Net Income	$ 65,633	$ 48,905	$ 150,310	$ 137,752
Other Comprehensive (Loss) Income, net of tax:
Unrealized (loss) gain on securities	(12,531)	3,320	(46,806)	17,861
Reclassification adjustment for securities gains included in net income	(11)	(2,988)	(30)	(4,639)
Amortization of net unrealized losses on available for sale securities transferred to held to maturity	791	0	791	0
Non-credit related unrealized gain on other-than-temporarily impaired debt securities	0	0	232	0
Amortization of net unrecognized pension and postretirement items	369	340	1,248	1,024
Other Comprehensive (Loss) Income	(11,382)	672	(44,565)	14,246
Total Comprehensive Income	$ 54,251	$ 49,577	$ 105,745	$ 151,998

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands		Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Total	Treasury Stock [Member]
Beginning Balance at Dec. 31, 2016		$ 2,121,115	$ 549,707	$ 1,467,602	$ 732,099	$ (38,449)	$ (589,844)
Beginning Balance (in shares) at Dec. 31, 2016			174,040
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		137,752			137,752
Other comprehensive loss		14,246				14,246
Stock issued, including related tax benefits (in shares)			1,017
Stock issued		7,037	$ 2,446	5,209			(618)
Stock-based compensation awards		3,339		3,339
Common stock cash dividends		(57,703)			(57,703)
Ending Balance at Sep. 30, 2017		2,225,786	$ 552,153	1,476,150	812,148	(24,203)	(590,462)
Ending Balance (in shares) at Sep. 30, 2017			175,057
Beginning Balance at Jun. 30, 2017						(24,875)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		48,905
Other comprehensive loss		672
Ending Balance at Sep. 30, 2017		2,225,786	$ 552,153	1,476,150	812,148	(24,203)	(590,462)
Ending Balance (in shares) at Sep. 30, 2017			175,057
Beginning Balance at Dec. 31, 2017		2,229,857	$ 552,232	1,478,389	821,619	(32,974)	(589,409)
Beginning Balance (in shares) at Dec. 31, 2017			175,170
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		150,310
Other comprehensive loss		(44,565)				(44,565)
Stock issued, including related tax benefits (in shares)			833
Stock issued		4,748	$ 1,936	2,773			39
Stock-based compensation awards (in shares)			16
Stock-based compensation awards		6,007	$ 40	5,967
Reclassification of stranded tax effects	[1]	0			7,101	(7,101)
Common stock cash dividends		(63,343)			(63,343)
Ending Balance at Sep. 30, 2018		2,283,014	$ 554,208	1,487,129	915,687	(84,640)	(589,370)
Ending Balance (in shares) at Sep. 30, 2018			176,019
Beginning Balance at Jun. 30, 2018						(73,258)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		65,633
Other comprehensive loss		(11,382)
Ending Balance at Sep. 30, 2018		$ 2,283,014	$ 554,208	$ 1,487,129	$ 915,687	$ (84,640)	$ (589,370)
Ending Balance (in shares) at Sep. 30, 2018			176,019
[1]	Result of adoption of ASU 2018-02, See Note 1 to Consolidated Financial Statements for further details.

Consolidated Statements of Sh_2

Consolidated Statements of Shareholders' Equity (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Stockholders' Equity [Abstract]
Cash dividends per share	$ 0.12	$ 0.11	$ 0.36	$ 0.33

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income	$ 150,310	$ 137,752
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for credit losses	38,707	16,575
Depreciation and amortization of premises and equipment	21,423	21,013
Amortization of tax credit investments	25,093	28,117
Net amortization of investment securities premiums	6,153	7,412
Investment securities gains, net	(37)	(7,139)
Gain on sales of mortgage loans held for sale	(10,158)	(10,122)
Proceeds from sales of mortgage loans held for sale	608,561	470,927
Originations of mortgage loans held for sale	(594,398)	(455,157)
Amortization of issuance costs and discounts on long-term debt	606	618
Stock-based compensation	6,007	3,339
Increase in accrued interest receivable	(5,674)	(3,788)
(Increase) decrease in other assets	(11,893)	9,991
Increase in accrued interest payable	1,834	936
Decrease in other liabilities	(3,843)	(4,943)
Total adjustments	82,381	77,779
Net cash provided by operating activities	232,691	215,531
CASH FLOWS FROM INVESTING ACTIVITIES:
Proceeds from sales of securities available for sale	54,638	44,485
Proceeds from principal repayments and maturities of securities held to maturity	15,475	0
Proceeds from principal repayments and maturities of securities available for sale	237,624	321,088
Purchase of securities available for sale	(459,799)	(344,569)
Increase in other interest-earning assets	(49,225)	(376,696)
Net increase in loans	(200,526)	(800,778)
Net change in tax credit investments	(29,857)	(24,758)
Net change in tax credit investments	47,096	21,084
Net cash used in investing activities	(478,766)	(1,202,312)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net increase in demand and savings deposits	342,080	1,014,697
Net increase in time deposits	109,402	114,219
Decrease in short-term borrowings	(131,959)	(242,566)
Additions to long-term debt	50,000	223,251
Repayments of long-term debt	(100,122)	(115,114)
Net proceeds from issuance of common stock	4,748	7,037
Dividends paid	(61,539)	(55,855)
Net cash provided by financing activities	212,610	945,669
Net Decrease in Cash and Restricted Cash	(33,465)	(41,112)
Cash and Restricted Cash at Beginning of Period	246,726	236,887
Cash and Restricted Cash at End of Period	213,261	195,775
Cash paid during the period for:
Interest	88,559	66,992
Income taxes	8,178	7,881
Supplemental schedule of certain noncash activities:
Transfer of student loans to loans held for sale	0	28,990
Transfer of available for sale securities to held to maturity securities	641,672	0
Restricted cash	$ 122,900	$ 96,000

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited consolidated financial statements of Fulton Financial Corporation (the "Corporation") have been prepared in conformity with U.S. generally accepted accounting principles ("U.S. GAAP") for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and notes required by U.S. GAAP for complete financial statements. The preparation of financial statements in accordance with U.S. GAAP requires management to make estimates and assumptions that affect the amounts of assets and liabilities as of the date of the financial statements as well as revenues and expenses during the period. Actual results could differ from those estimates. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. These consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the notes thereto included in the Corporation's Annual Report on Form 10-K for the year ended December 31, 2017 . Operating results for the three and nine months ended September 30, 2018 are not necessarily indicative of the results that may be expected for the year ending December 31, 2018 . The Corporation evaluates subsequent events through the date of filing of this Form 10-Q with the U.S. Securities and Exchange Commission ("SEC"). Recently Adopted Accounting Standards In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Codification ("ASC") Update 2014-09, "Revenue from Contracts with Customers." This standards update established a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. The core principle prescribed by this standards update is that an entity recognizes revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The standard applies to all contracts with customers, except those that are within the scope of other topics in the FASB ASC. The Corporation adopted this standard, and all subsequent Accounting Standards Updates ("ASU") that modified the standard, on January 1, 2018 under the modified retrospective approach with no material impact on its consolidated financial statements. The Corporation evaluated the impact of the adoption of ASC Update 2014-09 on its consolidated financial statements and did not identify any significant changes in the timing of revenue recognition as a result of this amended guidance. The sources of revenue for the Corporation are interest income from loans and investments, net of interest expense on deposits and borrowings, and non-interest income. Non-interest income is earned from various banking and financial services that the Corporation offers through its subsidiary banks. Revenue is recognized as earned based on contractual terms, as transactions occur, or as services are provided. Following is further detail of the various types of revenue the Corporation earns and when it is recognized. Interest income : Interest income is recognized on an accrual basis according to loan agreements, securities contracts or other such written contracts and is outside the scope of ASC Update 2014-09. Investment management and trust services: Consists of trust commission income, brokerage income, money market income and insurance commission income. Trust commission income consists of advisory fees that are based on market values of clients' managed portfolios and transaction fees for fiduciary services performed, both of which are recognized as earned. Brokerage income includes advisory fees which are recognized as earned on a monthly basis and transaction fees that are recognized when transactions occur. Money market income is based on the balances held in trust accounts and is recognized monthly. Insurance commission income is earned and recognized when policies are originated. Currently, no investment management and trust service income is based on performance or investment results. Service charges on deposit accounts: Consists of cash management, overdraft, non-sufficient fund fees and other service charges on deposit accounts. Revenue is primarily transactional and recognized when earned, at the time the transactions occur. Other service charges and fees: Consists of branch fees, automated teller machine fees, debit card income and merchant services fees. These fees are primarily transactional, and revenue is recognized when transactions occur. Also included in other service charges and fees are letter of credit fees, foreign exchange income and commercial loan interest rate swap fees, which are outside the scope of ASC Update 2014-09. Mortgage banking income: Consists of gains or losses on the sale of residential mortgage loans and mortgage loan servicing income. These revenues are outside the scope of ASC Update 2014-09. Other Income: Includes credit card income, gains on sales of Small Business Association ("SBA") loans, cash surrender value of life insurance, and other miscellaneous income. These items are either outside the scope of ASC Update 2014-09 or are immaterial. In January 2016, the FASB issued ASC Update 2016-01, "Financial Instruments - Overall: Recognition and Measurement of Financial Assets and Financial Liabilities." ASC Update 2016-01 provides guidance regarding the income statement impact of equity investments held by an entity and the recognition of changes in fair value of financial liabilities when the fair value option is elected. This standard requires equity investments to be measured at fair value, with changes recorded in net income. This ASU also requires the use of the exit price notion when measuring the fair value of financial instruments for disclosure purposes. ASC Update 2016-01 was effective for interim and annual reporting periods beginning after December 15, 2017. The Corporation adopted this standards update effective with its March 31, 2018 quarterly report on Form 10-Q and the adoption of ASC Update 2016-01 did not have a material impact on its consolidated financial statements. In November 2016, the FASB issued ASC Update 2016-18, "Statement of Cash Flows - Restricted Cash." This standards update provides guidance regarding the presentation of restricted cash in the statement of cash flows. The update requires companies to include amounts generally described as restricted cash and restricted cash equivalents, along with cash and cash equivalents, when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. It also requires an entity to disclose the nature of the restrictions on cash and cash equivalents. ASC Update 2016-18 was effective for interim and annual reporting periods beginning after December 15, 2017. The adoption of ASC Update 2016-18 did not have a material impact on its consolidated financial statements; however, in the second quarter of 2018 on the Consolidated Statements of Cash Flows, the Corporation corrected an error related to the adoption of this standards update to include restricted cash along with cash and cash equivalents in the reconciliation of beginning-of-period and end-of-period total amounts. The change had no impact on net income or retained earnings. In addition, the Corporation will revise the Consolidated Statements of Cash Flows for the three months ended March 31, 2018 when the amounts are next presented in the first quarter of 2019 . In February 2018, the FASB issued ASC Update 2018-02, "Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income." This ASU permits a reclassification from accumulated other comprehensive income ("AOCI") to retained earnings of the stranded tax effects resulting from the application of the Tax Cuts and Jobs Act of 2017 ("Tax Act"), which changed the federal corporate income tax rate from 35% to 21%. This ASU is effective for interim and annual reporting periods beginning after December 15, 2018, with early adoption permitted. The Corporation adopted this standards update effective January 1, 2018 and elected to reclassify $7.1 million of stranded tax effects from AOCI to retained earnings at the beginning of the period of adoption. The Corporation's policy for releasing income tax effects from accumulated other comprehensive income is to release them as investments are sold or mature and as pension and post-retirement liabilities are extinguished. Recently Issued Accounting Standards In February 2016, the FASB issued ASC Update 2016-02, "Leases." ASC Update 2016-02 requires a lessee to recognize for all leases with an initial term greater than twelve months: (1) a “right-of-use” asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term; and (2) a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis. ASC Update 2016-02 is effective for interim and annual reporting periods beginning after December 15, 2018. In July 2018, the FASB also issued amendments to ASC Update 2016-02 (ASC Updates 2018-10 and 2018-11), which allow for an alternative transition method that eliminates the requirement to restate the earliest prior period presented in an entity’s financial statements. Entities that elect this transition method still adopt ASC Update 2016-02 using the modified retrospective transition method, but they recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption rather than in the earliest period presented. The Corporation expects to adopt ASC Update 2016-02 in the first quarter of 2019 using this alternative transition method. The Corporation expects to elect to apply the package of practical expedients permitted within the new standard, which, among other things, allows it to carryforward the historical lease classification, initial direct costs for leases that commenced before the effective date, and the ability to use hindsight in evaluating lessee options to extend or terminate a lease or to purchase the underlying asset. Based on preliminary evaluation, the right-of-use asset and corresponding lease obligation liability, which represents substantially all of the Corporation’s operating lease commitments, is expected to be less than 1% of the Corporation's total assets at adoption. The Corporation does not believe the new lease standard will materially affect its consolidated net income. This estimate is based primarily on the present value of the unpaid future minimum lease payments. The final amount recognized may be impacted by assumptions relating to lease renewals and extensions before the effective date, and the interest rate used to discount those future lease obligations. ASC Update 2016-02 requires lessors to classify leases as a sales-type, direct financing or operating lease. Substantially all of the Corporation's leasing activities as lessor are under direct financing leases and it does not expect the new standard to have a material effect on its financial statements related to these leases and does not expect a significant change in its leasing activities between now and time of adoption. In June 2016, the FASB issued ASC Update 2016-13, "Financial Instruments - Credit Losses." The new impairment model prescribed by this standards update is a single impairment model for all financial assets (i.e., loans and held to maturity investments). The recognition of credit losses would be based on an entity’s current estimate of expected losses (referred to as the Current Expected Credit Loss model, or "CECL"), as opposed to recognition of losses only when they are probable under current U.S. GAAP. ASU 2016-13 also requires new disclosures for financial assets measured at amortized cost, loans and available-for-sale debt securities. Entities will apply the standard's provisions as a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is adopted. This adjustment will also be recognized in regulatory capital. ASC Update 2016-13 is effective for interim and annual reporting periods beginning after December 15, 2019. Early adoption is permitted. The Corporation intends to adopt this standards update effective with its March 31, 2020 quarterly report on Form 10-Q. The Corporation is currently evaluating the impact of the adoption of ASC Update 2016-13 on its consolidated financial statements and disclosures. While the Corporation is currently unable to reasonably estimate the impact of adopting ASU 2016-13, it expects that the impact of adoption could be significantly influenced by the composition, characteristics and quality of its loan portfolio as well as the prevailing economic conditions and forecasts as of the adoption date. The Corporation’s steering committee and working group, which are comprised of individuals from various functional areas, are assessing processes, portfolio segmentation, systems requirements and solutions and resources to implement this new accounting standard. Current activities also include data gathering and building loss models. In addition, the Corporation has engaged a third-party consultant to assist with these implementation efforts. In January 2017, the FASB issued ASC Update 2017-04, "Intangibles - Goodwill and Other." This standards update eliminates Step 2 of the goodwill impairment test which measures the impairment amount. Identifying and measuring impairment will take place in a single quantitative step. In addition, no separate qualitative assessment for reporting units with zero or negative carrying amounts is required. Entities must disclose the existence of these reporting units and the amount of goodwill allocated to them. This update should be applied on a prospective basis, and an entity is required to disclose the nature of and reason for the change in accounting principle upon transition. ASC Update 2017-04 is effective for annual or interim goodwill impairment tests in reporting periods beginning after December 15, 2019. Early adoption is permitted. The Corporation intends to adopt this standards update effective with its 2020 goodwill impairment test and does not expect the adoption of ASC Update 2017-04 to have a material impact on its consolidated financial statements. In March 2017, the FASB issued ASC Update 2017-08, "Premium Amortization on Purchased Callable Debt Securities." This standards update requires that a company amortize the premium on callable debt securities to the earliest call date versus current U.S. GAAP which requires amortization over the contractual life of the securities. The amortization period for callable debt securities purchased at a discount would not be impacted by the new accounting standards update. This amendment is to be adopted on a modified retrospective basis with a cumulative effect adjustment to retained earnings as of the beginning of the period of adoption. ASC Update 2017-08 is effective for annual or interim reporting periods beginning after December 15, 2018. Early adoption is permitted. The Corporation intends to adopt this standards update effective with its March 31, 2019 quarterly report on Form 10-Q and does not expect the adoption of ASC Update 2017-08 to have a material impact on its consolidated financial statements. In August 2018, the FASB issued ASC Update 2018-13, "Fair Value Measurement - Disclosure Framework." This standards update changes the fair value measurement disclosure requirements of ASC 820 "Fair Value Measurement." Among other things, the ASU modifies the disclosure objective paragraphs of ASC 820 to eliminate (1) “at a minimum” from the phrase “an entity shall disclose at a minimum” and (2) other similar “open ended” disclosure requirements to promote the appropriate exercise of discretion by entities. ASC Update 2018-13 is effective for annual or interim reporting periods beginning after December 15, 2019. Early adoption is permitted. The Corporation intends to adopt this standards update effective with its March 31, 2020 quarterly report on Form 10-Q. This standard will impact the Corporation's Fair Value Measurement disclosure but the Corporation does not expect the adoption of ASC Update 2018-13 to have a material impact on its consolidated financial statements. In August 2018, the FASB issued ASC Update 2018-14, "Compensation - Retirement Benefits - Defined Benefit Plans - General." This standards update amends ASC 715-20 to add, remove, and clarify disclosure requirements related to defined benefit pension and other postretirement plans. ASC Update 2018-14 is effective for annual reporting periods beginning after December 15, 2020. Early adoption is permitted. The Corporation intends to adopt this standards update effective with its March 31, 2021 quarterly report on Form 10-Q. This standard will impact the Corporation's disclosure relating to employee benefit plans, but the Corporation does not expect the adoption of ASC Update 2018-14 to have a material impact on its consolidated financial statements. In August 2018, the FASB issued ASC Update 2018-15, "Intangibles - Goodwill and Other - Internal-Use Software." This standards update requires a customer in a cloud computing arrangement that is a service contract to follow the internal-use software guidance in ASC 350-40 to determine which implementation costs to capitalize as assets. ASC Update 2018-15 is effective for annual or interim reporting periods beginning after December 15, 2019. Early adoption is permitted. The Corporation intends to adopt this standards update effective with its March 31, 2020 quarterly report on Form 10-Q and does not expect the adoption of ASC Update 2018-15 to have an impact on its consolidated financial statements. Reclassifications Certain amounts in the 2017 consolidated financial statements and notes have been reclassified to conform to the 2018 presentation. On the Consolidated Statements of Cash Flows, the net change in tax credit investments is presented as cash flows from investing activities. Prior to the quarter ended March 31, 2018, these cash flows were presented as cash flows from operating activities, included in the net increase (decrease) in other liabilities. The presentation of the cash flows for the nine months ended September 30, 2017 was changed to conform to this presentation, resulting in a $21.1 million decrease in net cash flows used in investing activities and a corresponding increase in net cash flows provided by operating activities. The change had no impact on net income or retained earnings. In addition, the Corporation will revise the Consolidated Statements of Cash Flows for each of the comparative 2017 periods in future filings.

Net Income Per Share

Net Income Per Share	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Net Income Per Share	Net Income Per Share Basic net income per share is calculated as net income divided by the weighted average number of shares outstanding. Diluted net income per share is calculated as net income divided by the weighted average number of shares outstanding plus the incremental number of shares added as a result of converting common stock equivalents, calculated using the treasury stock method. The Corporation’s common stock equivalents consist of outstanding stock options, restricted stock units ("RSUs") and performance-based restricted stock units ("PSUs"). PSUs are required to be included in weighted average shares outstanding if performance measures, as defined in each PSU award agreement, are met as of the end of the period. A reconciliation of weighted average shares outstanding used to calculate basic net income per share and diluted net income per share follows: Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 (in thousands) Weighted average shares outstanding (basic) 175,942 174,991 175,672 174,582 Impact of common stock equivalents 1,186 1,225 1,176 1,194 Weighted average shares outstanding (diluted) 177,128 176,216 176,848 175,776

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income	9 Months Ended
	Sep. 30, 2018
Equity [Abstract]
Accumulated Other Comprehensive Income	Accumulated Other Comprehensive (Loss) Income The following table presents changes in other comprehensive (loss) income: Before-Tax Amount Tax Effect Net of Tax Amount (in thousands) Three months ended September 30, 2018 Unrealized loss on securities $ (15,865 ) $ 3,334 $ (12,531 ) Reclassification adjustment for securities gains included in net income (1) (14 ) 3 (11 ) Amortization of net unrealized losses on AFS securities transferred to HTM (2) 1,000 (209 ) 791 Amortization of net unrecognized pension and postretirement items (3) 466 (97 ) 369 Total Other Comprehensive Loss $ (14,413 ) $ 3,031 $ (11,382 ) Three months ended September 30, 2017 Unrealized gain on securities $ 5,109 $ (1,789 ) $ 3,320 Reclassification adjustment for securities gains included in net income (1) (4,597 ) 1,609 (2,988 ) Amortization of net unrecognized pension and postretirement items (3) 523 (183 ) 340 Total Other Comprehensive Income $ 1,035 $ (363 ) $ 672 Nine months ended September 30, 2018 Unrealized loss on securities $ (59,250 ) $ 12,444 $ (46,806 ) Reclassification adjustment for securities gains included in net income (1) (37 ) 7 (30 ) Amortization of net unrealized losses on AFS securities transferred to HTM (2) 1,000 (209 ) 791 Non-credit related unrealized gains on other-than-temporarily impaired debt securities 294 (62 ) 232 Amortization of net unrecognized pension and postretirement items (3) 1,580 (332 ) 1,248 Total Other Comprehensive Loss $ (56,413 ) $ 11,848 $ (44,565 ) Nine months ended September 30, 2017 Unrealized gain on securities $ 27,482 $ (9,621 ) $ 17,861 Reclassification adjustment for securities gains included in net income (1) (7,139 ) 2,500 (4,639 ) Amortization of net unrecognized pension and postretirement items (3) 1,575 (551 ) 1,024 Total Other Comprehensive Income $ 21,918 $ (7,672 ) $ 14,246 (1) Amounts reclassified out of accumulated other comprehensive income. Before-tax amounts included in "Investment securities gains, net" on the consolidated statements of income. See Note 4, "Investment Securities," for additional details. (2) Amounts reclassified out of accumulated other comprehensive income. Before-tax amounts included as a reduction to "Interest Income" on the consolidated statements of income. See Note 4, "Investment Securities," for additional details. (3) Amounts reclassified out of accumulated other comprehensive income. Before-tax amounts included in "Salaries and employee benefits" on the consolidated statements of income. See Note 8, "Employee Benefit Plans," for additional details. The following table presents changes in each component of accumulated other comprehensive income (loss), net of tax: Unrealized Gains (Losses) on Investment Securities Not Other-Than-Temporarily Impaired Unrealized Non-Credit Gains (Losses) on Other-Than-Temporarily Impaired Debt Securities Unrecognized Pension and Postretirement Plan Income (Costs) Total (in thousands) Three months ended September 30, 2018 Balance at June 30, 2018 $ (56,690 ) $ 690 $ (17,258 ) $ (73,258 ) Other comprehensive loss before reclassifications (12,531 ) — — (12,531 ) Amounts reclassified from accumulated other comprehensive income (loss) (11 ) — 369 358 Amortization of net unrealized losses on AFS securities transferred to HTM 791 — — 791 Balance at September 30, 2018 $ (68,441 ) $ 690 $ (16,889 ) $ (84,640 ) Three months ended September 30, 2017 Balance at June 30, 2017 $ (10,157 ) $ 273 $ (14,991 ) $ (24,875 ) Other comprehensive income before reclassifications 3,320 — — 3,320 Amounts reclassified from accumulated other comprehensive income (loss) (2,988 ) — 340 (2,648 ) Balance at September 30, 2017 $ (9,825 ) $ 273 $ (14,651 ) $ (24,203 ) Nine months ended September 30, 2018 Balance at December 31, 2017 $ (18,509 ) $ 458 $ (14,923 ) $ (32,974 ) Other comprehensive income before reclassifications (46,806 ) 232 — (46,574 ) Amounts reclassified from accumulated other comprehensive income (loss) (30 ) — 1,248 1,218 Amortization of net unrealized losses on AFS securities transferred to HTM 791 — — 791 Reclassification of stranded tax effects (3,887 ) — (3,214 ) (7,101 ) Balance at September 30, 2018 $ (68,441 ) $ 690 $ (16,889 ) $ (84,640 ) Nine months ended September 30, 2017 Balance at December 31, 2016 $ (23,047 ) $ 273 $ (15,675 ) $ (38,449 ) Other comprehensive income before reclassifications 17,861 — — 17,861 Amounts reclassified from accumulated other comprehensive income (loss) (4,639 ) — 1,024 (3,615 ) Balance at September 30, 2017 $ (9,825 ) $ 273 $ (14,651 ) $ (24,203 )

Investment Securities

Investment Securities	9 Months Ended
	Sep. 30, 2018
Investments, Debt and Equity Securities [Abstract]
Investment Securities	Investment Securities The following table presents the amortized cost and estimated fair values of investment securities: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (in thousands) September 30, 2018 Available for Sale U.S. Government sponsored agency securities $ 31,527 $ 1 $ (437 ) $ 31,091 State and municipal securities 269,582 1,281 (9,723 ) 261,140 Corporate debt securities 93,482 950 (2,142 ) 92,290 Collateralized mortgage obligations 820,150 100 (23,016 ) 797,234 Residential mortgage-backed securities 497,614 1,873 (21,310 ) 478,177 Commercial mortgage-backed securities 251,969 — (6,218 ) 245,751 Auction rate securities 107,410 — (4,277 ) 103,133 Total $ 2,071,734 $ 4,205 $ (67,123 ) $ 2,008,816 September 30, 2018 Held to Maturity State and municipal securities $ 156,267 $ — $ (2,006 ) $ 154,261 Residential mortgage-backed securities 470,330 2 (1,741 ) 468,591 Total $ 626,597 $ 2 $ (3,747 ) $ 622,852 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (in thousands) December 31, 2017 Available for Sale U.S. Government sponsored agency securities $ 5,962 $ 2 $ (26 ) $ 5,938 State and municipal securities 405,860 5,638 (2,549 ) 408,949 Corporate debt securities 96,353 2,832 (1,876 ) 97,309 Collateralized mortgage obligations 611,927 491 (9,795 ) 602,623 Residential mortgage-backed securities 1,132,080 3,957 (15,241 ) 1,120,796 Commercial mortgage-backed securities 215,351 — (2,596 ) 212,755 Auction rate securities 107,410 — (8,742 ) 98,668 Total debt securities 2,574,943 12,920 (40,825 ) 2,547,038 Equity securities 776 142 — 918 Total $ 2,575,719 $ 13,062 $ (40,825 ) $ 2,547,956 On August 1, 2018, the Corporation transferred debt securities with an amortized cost of $665.5 million and an estimated fair value of $641.7 million from the available for sale classification to the held to maturity classification. These securities consisted of residential mortgage-backed securities ( $505.5 million amortized cost and $485.3 million estimated fair value) and state and municipal securities ( $160.0 million amortized cost and $156.4 million estimated fair value) and were transferred as the Corporation has the positive intent and ability to hold these securities to maturity. The transfer of debt securities into the held to maturity category from the available for sale category was recorded at fair value on the date of transfer. The net unrealized gains or losses at the transfer date are included in AOCI and are being amortized over the remaining lives of the securities. This amortization is expected to offset the amortization of the related premium or discount created by the investment securities transfer into the held to maturity classification, with no expected impact on future net income. Securities carried at $1.6 billion at September 30, 2018 and $1.8 billion at December 31, 2017 , were pledged as collateral to secure public and trust deposits and customer repurchase agreements. The amortized cost and estimated fair values of debt securities as of September 30, 2018 , by contractual maturity, are shown in the following table. Actual maturities may differ from contractual maturities as certain investment securities are subject to call or prepayment with or without call or prepayment penalties. Available for Sale Held to Maturity Amortized Estimated Amortized Estimated (in thousands) Due in one year or less $ 5,946 $ 5,949 $ — $ — Due from one year to five years 52,613 52,541 — — Due from five years to ten years 105,838 104,579 — — Due after ten years 337,604 324,585 156,267 154,261 502,001 487,654 156,267 154,261 Residential mortgage-backed securities (1) 497,614 478,177 470,330 468,591 Commercial mortgage-backed securities (1) 251,969 245,751 — — Collateralized mortgage obligations (1) 820,150 797,234 — — Total $ 2,071,734 $ 2,008,816 $ 626,597 $ 622,852 (1) Maturities for mortgage-backed securities and collateralized mortgage obligations are dependent upon the interest rate environment and prepayments on the underlying loans. The following table presents information related to the gross realized gains and losses on the sales of equity and debt securities: Gross Gross Net Gains (Losses) Three months ended September 30, 2018 (in thousands) Equity securities $ — $ — $ — Debt securities 116 (102 ) 14 Total $ 116 $ (102 ) $ 14 Three months ended September 30, 2017 Equity securities $ 4,817 $ — $ 4,817 Debt securities 12 (232 ) (220 ) Total $ 4,829 $ (232 ) $ 4,597 Nine months ended September 30, 2018 Equity securities $ 9 $ — $ 9 Debt securities 1,656 (1,628 ) 28 Total $ 1,665 $ (1,628 ) $ 37 Nine months ended September 30, 2017 Equity securities $ 7,167 $ — $ 7,167 Debt securities 218 (246 ) (28 ) Total $ 7,385 $ (246 ) $ 7,139 The cumulative balance of credit-related other-than-temporary impairment charges, previously recognized as components of earnings, for debt securities held by the Corporation at September 30, 2018 and September 30, 2017 was $ 11.5 million . There were no other-than-temporary impairment charges recognized for the three and nine months ended September 30, 2018 and September 30, 2017. The following table presents the gross unrealized losses and estimated fair values of investments, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, at September 30, 2018 and December 31, 2017: Less than 12 months 12 months or longer Total Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses September 30, 2018 Available for Sale (in thousands) U.S. Government sponsored agency securities $ 30,992 $ (437 ) $ — $ — $ 30,992 $ (437 ) State and municipal securities 112,366 (3,550 ) 73,856 (6,173 ) 186,222 (9,723 ) Corporate debt securities 56,159 (694 ) 22,700 (1,448 ) 78,859 (2,142 ) Collateralized mortgage obligations 620,047 (12,833 ) 168,560 (10,183 ) 788,607 (23,016 ) Residential mortgage-backed securities 105,850 (3,447 ) 329,007 (17,863 ) 434,857 (21,310 ) Commercial mortgage-backed securities 164,993 (3,591 ) 77,302 (2,627 ) 242,295 (6,218 ) Auction rate securities — — 103,133 (4,277 ) 103,133 (4,277 ) Total $ 1,090,407 $ (24,552 ) $ 774,558 $ (42,571 ) $ 1,864,965 $ (67,123 ) September 30, 2018 Held to Maturity State and municipal securities 154,261 (2,006 ) — — 154,261 (2,006 ) Residential mortgage-backed securities 454,544 (1,741 ) — — 454,544 (1,741 ) Total $ 608,805 $ (3,747 ) $ — $ — $ 608,805 $ (3,747 ) Less than 12 months 12 months or longer Total Estimated Unrealized Estimated Unrealized Estimated Unrealized December 31, 2017 Available for Sale (in thousands) U.S. Government sponsored agency securities $ 5,830 $ (26 ) $ — $ — $ 5,830 $ (26 ) State and municipal securities 11,650 (50 ) 118,297 (2,499 ) 129,947 (2,549 ) Corporate debt securities 4,544 (48 ) 32,163 (1,828 ) 36,707 (1,876 ) Collateralized mortgage obligations 303,932 (2,408 ) 187,690 (7,387 ) 491,622 (9,795 ) Residential mortgage-backed securities 511,378 (4,348 ) 500,375 (10,893 ) 1,011,753 (15,241 ) Commercial mortgage-backed securities 190,985 (2,118 ) 21,770 (478 ) 212,755 (2,596 ) Auction rate securities — — 98,668 (8,742 ) 98,668 (8,742 ) Total $ 1,028,319 $ (8,998 ) $ 958,963 $ (31,827 ) $ 1,987,282 $ (40,825 ) The Corporation’s collateralized mortgage obligations and mortgage-backed securities have contractual terms that generally do not permit the issuer to settle the securities at a price less than the amortized cost of the investment. The change in fair value of these securities is attributable to changes in interest rates and not credit quality, and the Corporation does not have the intent to sell and does not believe it will more likely than not be required to sell any of these securities prior to a recovery of their fair value to amortized cost. Therefore, the Corporation does not consider these investments to be other-than-temporarily impaired as of September 30, 2018 . As of September 30, 2018 , all of the auction rate securities (auction rate certificates, or "ARCs"), were rated above investment grade. Based on management’s evaluations, none of the ARCs were subject to any other-than-temporary impairment charges for the three and nine months ended September 30, 2018 . The Corporation does not have the intent to sell and does not believe it will more likely than not be required to sell any of these securities prior to a recovery of their fair value to amortized cost, which may be at maturity. The majority of the Corporation's available for sale corporate debt securities are issued by financial institutions. The following table presents the amortized cost and estimated fair values of corporate debt securities: September 30, 2018 December 31, 2017 Amortized cost Estimated fair value Amortized cost Estimated fair value (in thousands) Single-issuer trust preferred securities $ 20,860 $ 19,596 $ 31,335 $ 30,703 Subordinated debt 56,641 55,774 49,013 49,533 Senior debt 12,025 12,089 12,031 12,392 Pooled trust preferred securities — 875 — 707 Corporate debt securities issued by financial institutions 89,526 88,334 92,379 93,335 Other corporate debt securities 3,956 3,956 3,974 3,974 Available for sale corporate debt securities $ 93,482 $ 92,290 $ 96,353 $ 97,309 Single-issuer trust preferred securities had an unrealized loss of $1.3 million at September 30, 2018 . Two of the 11 single-issuer trust preferred securities, with an amortized cost of $2.0 million and an estimated fair value of $1.9 million at September 30, 2018 , were rated below investment grade by at least one ratings agency. The single-issuer trust preferred securities were rated "Baa2" or "BB+". One single-issuer trust preferred security with an amortized cost of $2.8 million and an estimated fair value of $2.5 million at September 30, 2018 was not rated by any ratings agency. Based on management’s evaluations, no corporate debt securities were subject to any other-than-temporary impairment charges for the three and nine months ended September 30, 2018 . The Corporation does not have the intent to sell and does not believe it will more likely than not be required to sell any of these securities prior to a recovery of their fair value to amortized cost, which may be at maturity.

Loans and Allowance for Credit

Loans and Allowance for Credit Losses	9 Months Ended
	Sep. 30, 2018
Receivables [Abstract]
Loans and Allowance for Credit Losses	Loans and Allowance for Credit Losses Loans, Net of Unearned Income Loans, net of unearned income are summarized as follows: September 30, December 31, 2017 (in thousands) Real-estate - commercial mortgage $ 6,337,984 $ 6,364,804 Commercial - industrial, financial and agricultural 4,288,823 4,300,297 Real-estate - residential mortgage 2,173,548 1,954,711 Real-estate - home equity 1,469,152 1,559,719 Real-estate - construction 979,857 1,006,935 Consumer 390,708 313,783 Leasing and other 312,207 291,556 Overdrafts 2,047 4,113 Loans, gross of unearned income 15,954,326 15,795,918 Unearned income (29,233 ) (27,671 ) Loans, net of unearned income $ 15,925,093 $ 15,768,247 The Corporation segments its loan portfolio by general loan type, or "portfolio segments," as presented in the table under the heading, "Loans, Net of Unearned Income," above. Certain portfolio segments are further disaggregated and evaluated collectively for impairment based on "class segments," which are largely based on the type of collateral underlying each loan. Commercial loans include both secured and unsecured loans. Construction loan class segments include loans secured by commercial real estate, loans to commercial borrowers secured by residential real estate and loans to individuals secured by residential real estate. Consumer loan class segments include direct consumer installment loans and indirect vehicle loans. Allowance for Credit Losses The allowance for credit losses consists of the allowance for loan losses and the reserve for unfunded lending commitments. The allowance for loan losses represents management’s estimate of incurred losses in the loan portfolio as of the balance sheet date and is recorded as a reduction to loans. The reserve for unfunded lending commitments represents management’s estimate of incurred losses in its unfunded loan commitments and letters of credit and is recorded in other liabilities on the consolidated balance sheets. The allowance for credit losses is increased by charges to expense, through the provision for credit losses, and decreased by charge-offs, net of recoveries. The Corporation’s allowance for credit losses includes: (1) specific allowances allocated to loans individually evaluated for impairment (FASB ASC Section 310-10-35); and (2) allowances calculated for pools of loans collectively evaluated for impairment (FASB ASC Subtopic 450-20). The following table presents the components of the allowance for credit losses: September 30, December 31, (in thousands) Allowance for loan losses $ 157,810 $ 169,910 Reserve for unfunded lending commitments 10,016 6,174 Allowance for credit losses $ 167,826 $ 176,084 The following table presents the activity in the allowance for credit losses: Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 (in thousands) Balance at beginning of period $ 169,247 $ 174,998 $ 176,084 $ 171,325 Loans charged off (6,883 ) (7,795 ) (55,440 ) (25,917 ) Recoveries of loans previously charged off 3,842 2,471 8,475 12,766 Net loans charged off (3,041 ) (5,324 ) (46,965 ) (13,151 ) Provision for credit losses 1,620 5,075 38,707 16,575 Balance at end of period $ 167,826 $ 174,749 $ 167,826 $ 174,749 Included in the provision for credit losses for the nine months ended September 30, 2018 was a $36.8 million provision related to a single, large commercial lending relationship (" Commercial Relationship "). In addition, loans charged off for the same period included a $33.9 million charge-off related to the Commercial Relationship . The Corporation had historically maintained an unallocated allowance for credit losses for factors and conditions that existed at the balance sheet date, but were not specifically identifiable, and to recognize the inherent imprecision in estimating and measuring loss exposure. In the second quarter of 2017, enhancements were made to allow for the impact of these factors and conditions to be quantified in the allowance allocation process. Accordingly, an unallocated allowance for credit losses is no longer necessary. The following table presents the activity in the allowance for loan losses by portfolio segment: Real Estate - Commercial Mortgage Commercial - Industrial, Financial and Agricultural Real Estate - Home Equity Real Estate - Residential Mortgage Real Estate - Construction Consumer Leasing, other and overdrafts Unallocated Total (in thousands) Three months ended September 30, 2018 Balance at June 30, 2018 $ 56,583 $ 59,045 $ 16,247 $ 14,504 $ 5,988 $ 1,699 $ 1,984 $ — $ 156,050 Loans charged off (650 ) (3,541 ) (743 ) (483 ) (212 ) (672 ) (582 ) — (6,883 ) Recoveries of loans previously charged off 928 731 217 317 664 390 595 — 3,842 Net loans charged off 278 (2,810 ) (526 ) (166 ) 452 (282 ) 13 — (3,041 ) Provision for loan losses (1) (2,750 ) (301 ) 2,890 3,774 (961 ) 1,429 720 — 4,801 Balance at September 30, 2018 $ 54,111 $ 55,934 $ 18,611 $ 18,112 $ 5,479 $ 2,846 $ 2,717 $ — $ 157,810 Three months ended September 30, 2017 Balance at June 30, 2017 $ 57,372 $ 67,642 $ 17,456 $ 16,439 $ 9,534 $ 1,794 $ 2,105 $ — $ 172,342 Loans charged off (483 ) (2,714 ) (547 ) (195 ) (2,744 ) (373 ) (739 ) — (7,795 ) Recoveries of loans previously charged off 106 665 252 219 629 193 407 — 2,471 Net loans charged off (377 ) (2,049 ) (295 ) 24 (2,115 ) (180 ) (332 ) — (5,324 ) Provision for loan losses (1) (2,008 ) 5,392 1,297 220 (283 ) 383 226 — 5,227 Balance at September 30, 2017 $ 54,987 $ 70,985 $ 18,458 $ 16,683 $ 7,136 $ 1,997 $ 1,999 $ — $ 172,245 Nine months ended September 30, 2018 Balance at December 31, 2017 $ 58,793 $ 66,280 $ 18,127 $ 16,088 $ 6,620 $ 2,045 $ 1,957 $ — $ 169,910 Loans charged off (1,283 ) (46,178 ) (1,967 ) (1,128 ) (976 ) (2,276 ) (1,632 ) — (55,440 ) Recoveries of loans previously charged off 1,528 2,347 694 520 1,414 1,015 957 — 8,475 Net loans charged off 245 (43,831 ) (1,273 ) (608 ) 438 (1,261 ) (675 ) — (46,965 ) Provision for loan losses (1) (4,927 ) 33,485 1,757 2,632 (1,579 ) 2,062 1,435 — 34,865 Balance at September 30, 2018 $ 54,111 $ 55,934 $ 18,611 $ 18,112 $ 5,479 $ 2,846 $ 2,717 $ — $ 157,810 Nine months ended September 30, 2017 Balance at December 31, 2016 $ 46,842 $ 54,353 $ 26,801 $ 22,929 $ 6,455 $ 3,574 $ 3,192 $ 4,533 $ 168,679 Loans charged off (1,949 ) (13,594 ) (1,837 ) (535 ) (3,765 ) (1,659 ) (2,578 ) — (25,917 ) Recoveries of loans previously charged off 1,490 6,830 604 600 1,550 899 793 — 12,766 Net loans charged off (459 ) (6,764 ) (1,233 ) 65 (2,215 ) (760 ) (1,785 ) — (13,151 ) Provision for loan losses (1) 8,604 23,396 (7,110 ) (6,311 ) 2,896 (817 ) 592 (4,533 ) 16,717 Balance at September 30, 2017 $ 54,987 $ 70,985 $ 18,458 $ 16,683 $ 7,136 $ 1,997 $ 1,999 $ — $ 172,245 (1) The provision for loan losses excluded a $3.2 million decrease and a $3.8 million increase in the reserve for unfunded lending commitments for the three and nine months ended September 30, 2018 , respectively, and a $152,000 and a $142,000 increase in the reserve for unfunded lending commitments for the three and nine months ended September 30, 2017, respectively. These amounts were reclassified to other liabilities on the consolidated balance sheets. The following table presents loans, net of unearned income and their related allowance for loan losses, by portfolio segment: Real Estate - Commercial Mortgage Commercial - Industrial, Financial and Agricultural Real Estate - Home Equity Real Estate - Residential Mortgage Real Estate - Construction Consumer Leasing, other and overdrafts Total (in thousands) Allowance for loan losses at September 30, 2018: Loans collectively evaluated for impairment $ 46,812 $ 47,028 $ 7,856 $ 8,369 $ 4,718 $ 2,841 $ 2,717 $ 120,341 Loans individually evaluated for impairment 7,299 8,906 10,755 9,743 761 5 — 37,469 $ 54,111 $ 55,934 $ 18,611 $ 18,112 $ 5,479 $ 2,846 $ 2,717 $ 157,810 Loans, net of unearned income at September 30, 2018: Loans collectively evaluated for impairment $ 6,290,143 $ 4,235,953 $ 1,444,898 $ 2,133,718 $ 971,167 $ 390,700 $ 285,021 $ 15,751,600 Loans individually evaluated for impairment 47,841 52,870 24,254 39,830 8,690 8 — 173,493 $ 6,337,984 $ 4,288,823 $ 1,469,152 $ 2,173,548 $ 979,857 $ 390,708 $ 285,021 $ 15,925,093 Allowance for loan losses at September 30, 2017: Loans collectively evaluated for impairment $ 47,261 $ 55,486 $ 7,632 $ 6,488 $ 5,702 $ 1,976 $ 1,999 $ 126,544 Loans individually evaluated for impairment 7,726 15,499 10,826 10,195 1,434 21 — 45,701 $ 54,987 $ 70,985 $ 18,458 $ 16,683 $ 7,136 $ 1,997 $ 1,999 $ 172,245 Loans, net of unearned income at September 30, 2017: Loans collectively evaluated for impairment $ 6,228,935 $ 4,162,857 $ 1,543,551 $ 1,845,329 $ 959,584 $ 302,415 $ 257,748 $ 15,300,419 Loans individually evaluated for impairment 46,205 60,218 23,922 42,578 13,524 33 — 186,480 $ 6,275,140 $ 4,223,075 $ 1,567,473 $ 1,887,907 $ 973,108 $ 302,448 $ 257,748 $ 15,486,899 Impaired Loans A loan is considered to be impaired if it is probable that all amounts will not be collected according to the contractual terms of the loan agreement. Impaired loans consist of all loans on non-accrual status and accruing troubled debt restructurings ("TDRs"). An allowance for loan losses is established for an impaired loan if its carrying value exceeds its estimated fair value. Impaired loans to borrowers with total commitments greater than or equal to $1.0 million are evaluated individually for impairment. Impaired loans to borrowers with total commitments less than $1.0 million are pooled and measured for impairment collectively. All loans individually evaluated for impairment are measured for losses on a quarterly basis. As of September 30, 2018 and December 31, 2017 , substantially all of the Corporation’s individually evaluated impaired loans with total commitments greater than or equal to $1.0 million were measured based on the estimated fair value of each loan’s collateral. Collateral could be in the form of real estate, in the case of impaired commercial mortgages and construction loans, or business assets, such as accounts receivable or inventory, in the case of commercial and industrial loans. Commercial and industrial loans may also be secured by real estate. As of September 30, 2018 and December 31, 2017 , approximately 93% and 94% , respectively, of impaired loans with principal balances greater than or equal to $1.0 million , whose primary collateral is real estate, were measured at estimated fair value of the collateral using appraisals that had been updated in the preceding 12 months, performed by state certified third-party appraisers. When updated appraisals are not obtained for loans evaluated for impairment that are secured by real estate, fair values are estimated based on the original appraisal values, as long as the original appraisal indicated an acceptable loan-to-value position and, in the opinion of the Corporation's internal credit administration staff, there has not been a significant deterioration in the collateral value since the original appraisal was performed. Original appraisals are typically used only when the estimated collateral value, as adjusted for the age of the appraisal, results in a current loan-to-value ratio that is lower than the Corporation's loan-to-value requirements for new loans (generally less than 70% ). The following table presents total impaired loans by class segment: September 30, 2018 December 31, 2017 Unpaid Principal Balance Recorded Investment Related Allowance Unpaid Principal Balance Recorded Investment Related Allowance (in thousands) With no related allowance recorded: Real estate - commercial mortgage $ 27,298 $ 25,665 $ — $ 26,728 $ 22,886 $ — Commercial 64,150 33,552 — 44,936 39,550 — Real estate - residential mortgage 3,171 3,170 — 4,575 4,575 — Construction 10,146 6,476 — 12,477 8,100 — 104,765 68,863 — 88,716 75,111 — With a related allowance recorded: Real estate - commercial mortgage 28,584 22,176 7,299 33,710 25,895 8,112 Commercial 24,530 19,318 8,906 29,816 24,175 11,406 Real estate - home equity 27,731 24,254 10,755 28,282 24,693 11,124 Real estate - residential mortgage 41,772 36,660 9,743 42,597 37,132 9,895 Construction 5,874 2,214 761 7,308 4,097 967 Consumer 8 8 5 26 26 17 128,499 104,630 37,469 141,739 116,018 41,521 Total $ 233,264 $ 173,493 $ 37,469 $ 230,455 $ 191,129 $ 41,521 As of September 30, 2018 and December 31, 2017 , there were $68.9 million and $75.1 million , respectively, of impaired loans that did not have a related allowance for loan loss. The estimated fair values of the collateral securing these loans exceeded their carrying amount, or the loans were previously charged down to realizable collateral values. Accordingly, no specific valuation allowance was considered to be necessary. The following table presents average impaired loans by class segment: Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 Average Interest Average Interest Average Interest Average Interest (in thousands) With no related allowance recorded: Real estate - commercial mortgage $ 26,051 $ 94 $ 21,698 $ 72 $ 25,702 $ 274 $ 22,770 $ 213 Commercial 30,157 66 33,044 46 35,098 208 29,309 128 Real estate - residential mortgage 3,182 20 4,616 27 3,872 71 4,645 79 Construction 6,845 — 9,042 5 7,408 — 7,043 11 66,235 180 68,400 150 72,080 553 63,767 431 With a related allowance recorded: Real estate - commercial mortgage 23,734 85 25,910 86 24,727 260 27,518 259 Commercial 23,687 51 25,152 34 23,934 149 24,097 97 Real estate - home equity 24,628 202 22,837 150 24,690 581 20,957 362 Real estate - residential mortgage 36,396 227 38,329 225 36,578 671 39,584 680 Construction 2,061 — 6,251 4 2,778 — 6,677 11 Consumer 10 — 34 — 18 — 36 — Leasing, other and overdrafts — — — — — — 356 — 110,516 565 118,513 499 112,725 1,661 119,225 1,409 Total $ 176,751 $ 745 $ 186,913 $ 649 $ 184,805 $ 2,214 $ 182,992 $ 1,840 (1) All impaired loans, excluding accruing TDRs, were non-accrual loans. Interest income recognized for the three and nine months ended September 30, 2018 and 2017 represents amounts earned on accruing TDRs. Credit Quality Indicators and Non-performing Assets The following is a summary of the Corporation's internal risk rating categories: • Pass : These loans do not currently pose undue credit risk and can range from the highest to average quality, depending on the degree of potential risk. • Special Mention : These loans constitute an undue and unwarranted credit risk, but not to a point of justifying a classification of substandard. Loans in this category are currently acceptable, but are nevertheless potentially weak. • Substandard or Lower : These loans are inadequately protected by current sound worth and paying capacity of the borrower. There exists a well-defined weakness or weaknesses that jeopardize the normal repayment of the debt. The risk rating process allows management to identify credits that potentially carry more risk in a timely manner and to allocate resources to managing troubled accounts. The Corporation believes that internal risk ratings are the most relevant credit quality indicator for the class segments presented in the preceding tables. The migration of loans through the various internal risk rating categories is a significant component of the allowance for credit loss methodology, which bases the probability of default on this migration. Assigning risk ratings involves judgment. The Corporation's loan review officers provide an independent assessment of risk rating accuracy. Ratings may be changed based on the ongoing monitoring procedures performed by loan officers or credit administration staff, or if specific loan review activities identify a deterioration or an improvement in the loan. The following table presents internal credit risk ratings for the indicated loan class segments: Pass Special Mention Substandard or Lower Total September 30, 2018 December 31, 2017 September 30, 2018 December 31, 2017 September 30, 2018 December 31, 2017 September 30, 2018 December 31, 2017 (dollars in thousands) Real estate - commercial mortgage $ 6,032,828 $ 6,066,396 $ 170,362 $ 147,604 $ 134,794 $ 150,804 $ 6,337,984 $ 6,364,804 Commercial - secured 3,839,283 3,831,485 150,310 121,842 138,604 179,113 4,128,197 4,132,440 Commercial - unsecured 152,796 159,620 3,898 5,478 3,932 2,759 160,626 167,857 Total commercial - industrial, financial and agricultural 3,992,079 3,991,105 154,208 127,320 142,536 181,872 4,288,823 4,300,297 Construction - commercial residential 120,249 143,759 7,677 5,259 8,379 14,084 136,305 163,102 Construction - commercial 756,477 761,218 552 846 3,616 3,752 760,645 765,816 Total construction (excluding Construction - other) 876,726 904,977 8,229 6,105 11,995 17,836 896,950 928,918 $ 10,901,633 $ 10,962,478 $ 332,799 $ 281,029 $ 289,325 $ 350,512 $ 11,523,757 $ 11,594,019 % of Total 94.6 % 94.6 % 2.9 % 2.4 % 2.5 % 3.0 % 100.0 % 100.0 % The Corporation does not assign internal risk ratings to smaller balance, homogeneous loans, such as home equity, residential mortgage, construction loans to individuals secured by residential real estate, consumer and lease receivables. For these loans, the most relevant credit quality indicator is delinquency status. The migration of loans through the various delinquency status categories is a significant component of the allowance for credit losses methodology for those loans, which bases the probability of default on this migration. The following table presents a summary of performing, delinquent and non-performing loans for the indicated loan class segments: Performing Delinquent (1) Non-performing (2) Total September 30, 2018 December 31, 2017 September 30, 2018 December 31, 2017 September 30, 2018 December 31, 2017 September 30, 2018 December 31, 2017 (dollars in thousands) Real estate - home equity $ 1,447,184 $ 1,535,557 $ 11,886 $ 12,655 $ 10,082 $ 11,507 $ 1,469,152 $ 1,559,719 Real estate - residential mortgage 2,131,239 1,914,888 23,233 18,852 19,076 20,971 2,173,548 1,954,711 Construction - other 82,417 77,403 — 203 490 411 82,907 78,017 Consumer - direct 58,259 54,828 311 315 60 70 58,630 55,213 Consumer - indirect 328,423 254,663 3,435 3,681 220 226 332,078 258,570 Total consumer 386,682 309,491 3,746 3,996 280 296 390,708 313,783 Leasing, other and overdrafts 282,812 267,111 2,119 855 90 32 285,021 267,998 $ 4,330,334 $ 4,104,450 $ 40,984 $ 36,561 $ 30,018 $ 33,217 $ 4,401,336 $ 4,174,228 % of Total 98.4 % 98.3 % 0.9 % 0.9 % 0.7 % 0.8 % 100.0 % 100.0 % (1) Includes all accruing loans 30 days to 89 days past due. (2) Includes all accruing loans 90 days or more past due and all non-accrual loans. The following table presents non-performing assets: September 30, December 31, (in thousands) Non-accrual loans $ 106,433 $ 124,749 Loans 90 days or more past due and still accruing 13,663 10,010 Total non-performing loans 120,096 134,759 Other real estate owned (OREO) 10,684 9,823 Total non-performing assets $ 130,780 $ 144,582 The following tables present past due status and non-accrual loans by portfolio segment and class segment: September 30, 2018 30-59 Days Past Due 60-89 Days Past Due ≥ 90 Days Past Due and Accruing Non- accrual Total ≥ 90 Days Total Past Due Current Total (in thousands) Real estate - commercial mortgage $ 12,129 $ 1,599 $ 5,242 $ 32,151 $ 37,393 $ 51,121 $ 6,286,863 $ 6,337,984 Commercial - secured 6,705 1,218 835 41,327 42,162 50,085 4,078,112 4,128,197 Commercial - unsecured 357 437 29 1,200 1,229 2,023 158,603 160,626 Total commercial - industrial, financial and agricultural 7,062 1,655 864 42,527 43,391 52,108 4,236,715 4,288,823 Real estate - home equity 9,383 2,503 2,037 8,045 10,082 21,968 1,447,184 1,469,152 Real estate - residential mortgage 17,731 5,502 4,056 15,020 19,076 42,309 2,131,239 2,173,548 Construction - commercial residential 157 225 896 8,379 9,275 9,657 126,648 136,305 Construction - commercial — — — 19 19 19 760,626 760,645 Construction - other — — 198 292 490 490 82,417 82,907 Total real estate - construction 157 225 1,094 8,690 9,784 10,166 969,691 979,857 Consumer - direct 225 86 60 — 60 371 58,259 58,630 Consumer - indirect 2,903 532 220 — 220 3,655 328,423 332,078 Total consumer 3,128 618 280 — 280 4,026 386,682 390,708 Leasing, other and overdrafts 1,739 380 90 — 90 2,209 282,812 285,021 Total $ 51,329 $ 12,482 $ 13,663 $ 106,433 $ 120,096 $ 183,907 $ 15,741,186 $ 15,925,093 December 31, 2017 30-59 Days Past Due 60-89 Days Past Due ≥ 90 Days Past Due and Accruing Non- accrual Total ≥ 90 Days Total Past Due Current Total (in thousands) Real estate - commercial mortgage $ 9,456 $ 4,223 $ 625 $ 34,822 $ 35,447 $ 49,126 $ 6,315,678 $ 6,364,804 Commercial - secured 4,778 5,254 1,360 52,255 53,615 63,647 4,068,793 4,132,440 Commercial - unsecured 305 10 45 649 694 1,009 166,848 167,857 Total commercial - industrial, financial and agricultural 5,083 5,264 1,405 52,904 54,309 64,656 4,235,641 4,300,297 Real estate - home equity 9,640 3,015 2,372 9,135 11,507 24,162 1,535,557 1,559,719 Real estate - residential mortgage 11,961 6,891 5,280 15,691 20,971 39,823 1,914,888 1,954,711 Construction - commercial residential — 439 — 11,767 11,767 12,206 150,896 163,102 Construction - commercial 483 — — 19 19 502 765,314 765,816 Construction - other 203 — — 411 411 614 77,403 78,017 Total real estate - construction 686 439 — 12,197 12,197 13,322 993,613 1,006,935 Consumer - direct 260 55 70 — 70 385 54,828 55,213 Consumer - indirect 3,055 626 226 — 226 3,907 254,663 258,570 Total consumer 3,315 681 296 — 296 4,292 309,491 313,783 Leasing, other and overdrafts 568 287 32 — 32 887 267,111 267,998 Total $ 40,709 $ 20,800 $ 10,010 $ 124,749 $ 134,759 $ 196,268 $ 15,571,979 $ 15,768,247 The following table presents TDRs, by class segment: September 30, December 31, (in thousands) Real-estate - residential mortgage $ 24,810 $ 26,016 Real-estate - commercial mortgage 15,690 13,959 Real estate - home equity 16,208 15,558 Commercial 10,342 10,820 Consumer 8 26 Total accruing TDRs 67,058 66,379 Non-accrual TDRs (1) 23,238 29,051 Total TDRs $ 90,296 $ 95,430 (1) Included in non-accrual loans in the preceding table detailing non-performing assets. The following table presents TDRs, by class segment and type of concession for loans that were modified during the three and nine months ended September 30, 2018 and 2017 : Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 Number of Loans Post-Modification Recorded Investment Number of Loans Post-Modification Recorded Investment Number of Loans Post-Modification Recorded Investment Number of Loans Post-Modification Recorded Investment (dollars in thousands) Real estate – residential mortgage: Extend maturity with rate concession 3 $ 330 2 $ 468 3 $ 330 2 $ 468 Extend maturity without rate concession 1 267 2 151 2 344 4 488 Bankruptcy — — — — 1 5 2 335 Real estate - commercial mortgage: Extend maturity without rate concession — — 2 1,247 6 8,261 6 2,228 Bankruptcy — — — — — — 1 12 Real estate - home equity: Extend maturity without rate concession 23 985 14 1,315 63 3,607 47 3,874 Bankruptcy 1 17 6 127 8 438 23 1,643 Commercial: Extend maturity without rate concession 2 913 1 160 7 2,064 9 5,853 Bankruptcy — — — — — — 1 490 Commercial – unsecured: Extend maturity without rate concession — — — — — — 1 33 Construction - commercial residential: Extend maturity without rate concession — — — — — — 1 1,204 Total 30 $ 2,512 27 $ 3,468 90 $ 15,049 97 $ 16,628 The following table presents TDRs, by class segment, as of September 30, 2018 and 2017 that were modified in the previous 12 months and had a post-modification payment default during the nine months ended September 30, 2018 and 2017 . The Corporation defines a payment default as a single missed payment. 2018 2017 Number of Loans Recorded Investment Number of Loans Recorded Investment (dollars in thousands) Real estate - residential mortgage 6 $ 724 5 $ 1,321 Real estate - commercial mortgage 2 452 3 653 Real estate - home equity 25 1,591 27 1,598 Commercial 4 5,042 2 264 Construction — — 2 1,609 Total 37 $ 7,809 39 $ 5,445

Mortgage Servicing Rights

Mortgage Servicing Rights	9 Months Ended
	Sep. 30, 2018
Transfers and Servicing [Abstract]
Mortgage Servicing Rights	Mortgage Servicing Rights The following table summarizes the changes in mortgage servicing rights ("MSRs"), which are included in other assets on the consolidated balance sheets: Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 (in thousands) Amortized cost: Balance at beginning of period $ 37,894 $ 38,180 $ 37,663 $ 38,822 Originations of mortgage servicing rights 2,018 1,333 5,247 3,719 Amortization (1,684 ) (1,639 ) (4,682 ) (4,667 ) Balance at end of period $ 38,228 $ 37,874 $ 38,228 $ 37,874 Valuation allowance: Balance at beginning of period $ — $ — $ — $ (1,291 ) Reductions to valuation allowance — — — 1,291 Balance at end of period $ — $ — $ — $ — Net MSRs at end of period $ 38,228 $ 37,874 $ 38,228 $ 37,874 MSRs represent the economic value of existing contractual rights to service mortgage loans that have been sold. Accordingly, actual and expected prepayments of the underlying mortgage loans can impact the value of MSRs. The Corporation accounts for MSRs at the lower of amortized cost or fair value. The fair value of MSRs is estimated by discounting the estimated cash flows from servicing income, net of expense, over the expected life of the underlying loans at a discount rate commensurate with the risk associated with these assets. Expected life is based on the contractual terms of the loans, as adjusted for prepayment projections. Based on its fair value analysis, the Corporation determined a valuation allowance was not necessary as of September 30, 2018 and September 30, 2017. Reductions and additions to the valuation allowance are recorded as increases and decreases, respectively, to mortgage banking income on the consolidated statements of income.

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Stock-Based Compensation The Corporation grants equity awards to employees, consisting of stock options, restricted stock, RSUs and PSUs under its Amended and Restated Equity and Cash Incentive Compensation Plan ("Employee Equity Plan"). In addition, employees may purchase stock under the Corporation’s Employee Stock Purchase Plan. The fair value of equity awards granted to employees is recognized as compensation expense over the period during which employees are required to provide service in exchange for such awards. Compensation expense for PSUs is also recognized over the period during which employees are required to provide service in exchange for such awards, however, compensation expense may vary based on the expectations for actual performance relative to defined performance measures. The Corporation also grants equity awards to non-employee members of its board of directors under the 2011 Directors’ Equity Participation Plan ("Directors’ Plan"). Under the Directors’ Plan, the Corporation can grant equity awards to non-employee holding company and subsidiary bank directors in the form of stock options, restricted stock or common stock. Equity awards issued under the Employee Equity Plan are generally granted annually and become fully vested over or after a three -year vesting period. The vesting period for non-performance-based awards represents the period during which employees are required to provide service in exchange for such awards. Equity awards under the Directors' Plan generally vest immediately upon grant. Certain events, as defined in the Employee Equity Plan and the Directors' Plan, result in the acceleration of the vesting of equity awards. Fair values for RSUs and a majority of PSUs are based on the trading price of the Corporation’s stock on the date of grant and earn dividend equivalents during the vesting period, which are forfeitable if the awards do not vest. The fair value of certain PSUs are estimated through the use of the Monte Carlo valuation methodology as of the date of grant. As of September 30, 2018 , the Employee Equity Plan had 10.6 million shares reserved for future grants through 2023 , and the Directors’ Plan had approximately 329,000 shares reserved for future grants through 2021 . The following table presents compensation expense and the related tax benefits for equity awards recognized in the consolidated statements of income: Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 (in thousands) Compensation expense $ 1,823 $ 1,570 $ 6,007 $ 3,339 Tax benefit (492 ) (628 ) (2,028 ) (3,312 ) Stock-based compensation expense, net of tax benefit $ 1,331 $ 942 $ 3,979 $ 27 The tax benefit shown in the preceding table does not equal the Corporation's statutory tax rate of 21% of compensation expense in 2018 and 35% of compensation expense in 2017 as a result of excess tax benefits related to stock option exercises and vesting RSUs and PSUs during these periods, which were recorded as reductions to income tax expense.

Employee Benefit Plans

Employee Benefit Plans	9 Months Ended
	Sep. 30, 2018
Retirement Benefits [Abstract]
Employee Benefit Plans	Employee Benefit Plans The net periodic pension cost for the Corporation’s Defined Benefit Pension Plan ("Pension Plan") consisted of the following components: Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 (in thousands) Interest cost $ 763 $ 830 $ 2,290 $ 2,490 Expected return on plan assets (512 ) (451 ) (1,536 ) (1,353 ) Net amortization and deferral 607 663 1,822 1,989 Net periodic pension cost $ 858 $ 1,042 $ 2,576 $ 3,126 The components of the net benefit for the Corporation’s Postretirement Benefits Plan ("Postretirement Plan") consisted of the following components: Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 (in thousands) Interest cost $ 13 $ 17 $ 42 $ 51 Net accretion and deferral (139 ) (141 ) (419 ) (423 ) Net periodic benefit $ (126 ) $ (124 ) $ (377 ) $ (372 ) The Corporation recognizes the funded status of its Pension Plan and Postretirement Plan on the consolidated balance sheets and recognizes the change in that funded status through other comprehensive income.

Derivative Financial Instrument

Derivative Financial Instruments	9 Months Ended
	Sep. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments The Corporation manages its exposure to certain interest rate and foreign currency risks through the use of derivatives. None of the Corporation's outstanding derivative contracts are designated as hedges, and none are entered into for speculative purposes. Derivative instruments are carried at fair value, with changes in fair value recognized in earnings as components of non-interest income or non-interest expense on the consolidated statements of income. Derivative contracts create counterparty credit risk with both the Corporation's customers and with institutional counterparties. The Corporation manages counterparty credit risk through its credit approval processes, monitoring procedures and obtaining adequate collateral, when the Corporation determines it is appropriate to do so and in accordance with counterparty contracts. Mortgage Banking Derivatives In connection with its mortgage banking activities, the Corporation enters into commitments to originate certain fixed-rate residential mortgage loans for customers, also referred to as interest rate locks. In addition, the Corporation enters into forward commitments for the future sales or purchases of mortgage-backed securities to or from third-party counterparties to hedge the effect of changes in interest rates on the values of both the interest rate locks and mortgage loans held for sale. Forward sales commitments may also be in the form of commitments to sell individual mortgage loans at a fixed price at a future date. The amount necessary to settle each interest rate lock is based on the price that secondary market investors would pay for loans with similar characteristics, including interest rate and term, as of the date fair value is measured. Gross derivative assets and liabilities are recorded in other assets and other liabilities, respectively, on the consolidated balance sheets, and changes in fair values during the period are recorded in mortgage banking income on the consolidated statements of income. Interest Rate Swaps The Corporation enters into interest rate swaps with certain qualifying commercial loan customers to meet their interest rate risk management needs. The Corporation simultaneously enters into interest rate swaps with dealer counterparties, with identical notional amounts and terms. The net result of these interest rate swaps is that the customer pays a fixed rate of interest and the Corporation receives a floating rate. These interest rate swaps are derivative financial instruments and the gross fair values are recorded in other assets and other liabilities on the consolidated balance sheets, with changes in fair values during the period recorded in other non-interest expense on the consolidated statements of income. Fulton Bank, N.A. ("Fulton Bank"), the Corporation's largest banking subsidiary, exceeded $10 billion in total assets as of December 31, 2016 and is required to clear all eligible interest rate swap contracts with a central counterparty, effective January 1, 2017. As a result, Fulton Bank is subject to the regulations of the Commodity Futures Trading Commission ("CFTC"). Foreign Exchange Contracts The Corporation enters into foreign exchange contracts to accommodate the needs of its customers. Foreign exchange contracts are commitments to buy or sell foreign currency on a specific date at a contractual price. The Corporation limits its foreign exchange exposure with customers by entering into contracts with institutional counterparties to mitigate its foreign exchange risk. The Corporation also holds certain amounts of foreign currency with international correspondent banks ("Foreign Currency Nostro Accounts"). The Corporation limits the total overnight net foreign currency open positions, which is defined as an aggregate of all outstanding contracts and Foreign Currency Nostro Account balances, to $500,000 . Gross fair values are recorded in other assets and other liabilities on the consolidated balance sheets, with changes in fair values during the period recorded in other service charges and fees on the consolidated statements of income. The following table presents a summary of the notional amounts and fair values of derivative financial instruments: September 30, 2018 December 31, 2017 Notional Asset Notional Asset (in thousands) Interest Rate Locks with Customers Positive fair values $ 143,869 $ 904 $ 129,469 $ 1,059 Negative fair values 11,535 (77 ) 8,957 (59 ) Net interest rate locks with customers 827 1,000 Forward Commitments Positive fair values 122,856 480 3,856 34 Negative fair values — — 100,808 (213 ) Net forward commitments 480 (179 ) Interest Rate Swaps with Customers Positive fair values 548,277 6,922 1,316,548 24,505 Negative fair values 1,882,655 (71,175 ) 716,634 (18,978 ) Net interest rate swaps with customers (64,253 ) 5,527 Interest Rate Swaps with Dealer Counterparties Positive fair values (1) (3) 1,882,655 58,773 716,634 18,941 Negative fair values (2) (3) 548,277 (3,778 ) 1,316,548 (19,764 ) Net interest rate swaps with dealer counterparties 54,995 (823 ) Foreign Exchange Contracts with Customers Positive fair values 8,797 193 4,852 276 Negative fair values 9,176 (277 ) 5,914 (119 ) Net foreign exchange contracts with customers (84 ) 157 Foreign Exchange Contracts with Correspondent Banks Positive fair values 10,506 325 7,960 184 Negative fair values 9,239 (192 ) 6,048 (255 ) Net foreign exchange contracts with correspondent banks 133 (71 ) Net derivative fair value asset $ (7,902 ) $ 5,611 (1) Includes centrally cleared interest rate swaps with a notional amount of $416.1 million and a fair value of $0 as of September 30, 2018 and a notional amount of $24.4 million and a fair value of $0 as of December 31, 2017 . (2) Includes centrally cleared interest rate swaps with a notional amount of $249.7 million and a fair value of $0 as of September 30, 2018 and a notional amount of $377.1 million and a fair value of $0 as of December 31, 2017 . (3) The variation margin posted as collateral on centrally cleared interest rate swaps, which represents the fair value of such swaps, is legally characterized as settlements of the outstanding derivative contracts instead of cash collateral. Accordingly, the fair values of centrally cleared interest rate swaps were offset by variation margins of $9.3 million at September 30, 2018 , increasing the fair value of such swaps to $0 , and $4.6 million at December 31, 2017 , reducing the fair value of such swaps to $0 . The following table presents a summary of the fair value (losses) gains on derivative financial instruments: Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 (in thousands) Interest rate locks with customers $ (533 ) $ (59 ) $ (173 ) $ 631 Forward commitments 974 (48 ) 659 (2,270 ) Interest rate swaps with customers (14,763 ) (47 ) (69,780 ) 12,947 Interest rate swaps with dealer counterparties (1) 11,193 1,248 55,818 (6,582 ) Foreign exchange contracts with customers (225 ) 140 (241 ) (177 ) Foreign exchange contracts with correspondent banks 166 (111 ) 204 219 Net fair value (losses) gains on derivative financial instruments $ (3,188 ) $ 1,123 $ (13,513 ) $ 4,768 (1) Not included is $3.6 million and $13.9 million , respectively, of gains representing the change in the variation margin for the three and nine months ended September 30, 2018 and $1.2 million and $6.3 million , respectively, of losses representing the change in the variation margin for the three and nine months ended September 30, 2017 . Fair Value Option The Corporation has elected to measure mortgage loans held for sale at fair value. Derivative financial instruments related to mortgage banking activities are also recorded at fair value, as noted above. The Corporation determines fair value for its mortgage loans held for sale based on the price that secondary market investors would pay for loans with similar characteristics, including interest rate and term, as of the date fair value is measured. Changes in fair values during the period are recorded as components of mortgage banking income on the consolidated statements of income. The following table presents a summary of the Corporation’s mortgage loans held for sale: September 30, December 31, (in thousands) Cost (1) $ 27,271 $ 31,069 Fair value 27,525 31,530 (1) Cost basis of mortgage loans held for sale represents the unpaid principal balance. For the three and nine months ended September 30, 2018 , losses related to changes in fair values of mortgage loans held for sale were $334,000 and $207,000 , respectively. During the three months ended September 30, 2017 , losses related to changes in fair values of mortgage loans held for sale were $120,000 and during the nine months ended September 30, 2017 , gains related to changes in fair values of mortgage loans held for sale were $445,000 . Balance Sheet Offsetting Although certain financial assets and liabilities may be eligible for offset on the consolidated balance sheets because they are subject to master netting arrangements or similar agreements, the Corporation elects to not offset such qualifying assets and liabilities. The Corporation is a party to interest rate swap transactions with financial institution counterparties and customers, disclosed in detail above. Under these agreements, the Corporation has the right to net-settle multiple contracts with the same counterparty in the event of default on, or termination of, any one contract. Cash collateral is posted by the party with a net liability position in accordance with contract thresholds and can be used to settle the fair value of the interest rate swap agreements in the event of default. A daily settlement occurs through a clearing agent for changes in the fair value of centrally cleared derivatives. As a result, the total fair values of interest rate swap derivative assets and derivative liabilities recognized on the consolidated balance sheet are not equal and offsetting. The Corporation is also a party to foreign currency exchange contracts with financial institution counterparties, under which the Corporation has the right to net-settle multiple contracts with the same counterparty in the event of default on, or termination of, any one contract. As with interest rate swap contracts, collateral is posted by the party with a net liability position in accordance with contract thresholds and can be used to settle the fair value of the foreign currency exchange contracts in the event of default. The Corporation also enters into agreements with customers in which it sells securities subject to an obligation to repurchase the same or similar securities, referred to as repurchase agreements. Under these agreements, the Corporation may transfer legal control over the assets but still maintain effective control through agreements that both entitle and obligate the Corporation to repurchase the assets. Therefore, repurchase agreements are reported as secured borrowings, classified in short-term borrowings on the consolidated balance sheets, while the securities underlying the repurchase agreements remain classified with investment securities on the consolidated balance sheets. The Corporation has no intention of setting off these amounts. Therefore, these repurchase agreements are not eligible for offset. The following table presents the Corporation's financial instruments that are eligible for offset, and the effects of offsetting, on the consolidated balance sheets: Gross Amounts Gross Amounts Not Offset Recognized on the Consolidated on the Balance Sheets Consolidated Financial Cash Net Balance Sheets Instruments (1) Collateral (2) Amount (in thousands) September 30, 2018 Interest rate swap derivative assets $ 65,695 $ (4,662 ) $ (56,630 ) $ 4,403 Foreign exchange derivative assets with correspondent banks 325 (192 ) — 133 Total $ 66,020 $ (4,854 ) $ (56,630 ) $ 4,536 Interest rate swap derivative liabilities $ 74,954 $ (4,662 ) $ (13,628 ) $ 56,664 Foreign exchange derivative liabilities with correspondent banks 192 (192 ) — — Total $ 75,146 $ (4,854 ) $ (13,628 ) $ 56,664 December 31, 2017 Interest rate swap derivative assets $ 43,446 $ (16,844 ) $ — $ 26,602 Foreign exchange derivative assets with correspondent banks 184 (184 ) — — Total $ 43,630 $ (17,028 ) $ — $ 26,602 Interest rate swap derivative liabilities $ 38,742 $ (16,844 ) $ (6,588 ) $ 15,310 Foreign exchange derivative liabilities with correspondent banks 255 (184 ) — 71 Total $ 38,997 $ (17,028 ) $ (6,588 ) $ 15,381 (1) For interest rate swap assets, amounts represent any derivative liability fair values that could be offset in the event of counterparty or customer default. For interest rate swap liabilities, amounts represent any derivative asset fair values that could be offset in the event of counterparty or customer default. (2) Amounts represent cash collateral received from the counterparty or posted by the Corporation on interest rate swap transactions and foreign exchange contracts with financial institution counterparties. Interest rate swaps with customers are collateralized by the same collateral securing the underlying loans to those borrowers. Cash and securities collateral amounts are included in the table only to the extent of the net derivative fair values.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Commitments The Corporation is a party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers. Those financial instruments include commitments to extend credit and letters of credit, which involve, to varying degrees, elements of credit risk and interest rate risk in excess of the amounts recognized on the Corporation’s consolidated balance sheets. Exposure to credit loss in the event of nonperformance by the other party to the financial instrument for commitments to extend credit and letters of credit is represented by the outstanding amount of those instruments. The outstanding amounts of commitments to extend credit and letters of credit were as follows: September 30, December 31, 2017 (in thousands) Commitments to extend credit $ 6,562,515 $ 6,205,029 Standby letters of credit 325,386 326,973 Commercial letters of credit 42,285 41,801 The Corporation records a reserve for unfunded lending commitments, which represents management’s estimate of losses associated with unused commitments to extend credit and letters of credit. See Note 5, "Loans and Allowance for Credit Losses," for additional details. Residential Lending The Corporation originates and sells residential mortgages to secondary market investors. The Corporation provides customary representations and warranties to secondary market investors that specify, among other things, that the loans have been underwritten to the standards of the secondary market investor. The Corporation may be required to repurchase specific loans, or reimburse the investor for a credit loss incurred on a sold loan if it is determined that the representations and warranties have not been met. Under some agreements with secondary market investors, the Corporation may have additional credit exposure beyond customary representations and warranties, based on the specific terms of those agreements. The Corporation maintains a reserve for estimated credit losses related to loans sold to investors. As of September 30, 2018 and December 31, 2017, the total reserve for losses on residential mortgage loans sold was $1.9 million and $2.1 million , respectively, including reserves for both representation and warranty and credit loss exposures. Legal Proceedings The Corporation is involved in various pending and threatened claims and other legal proceedings in the ordinary course of its business activities. The Corporation evaluates the possible impact of these matters, taking into consideration the most recent information available. A loss reserve is established for those matters for which the Corporation believes a loss is both probable and reasonably estimable. Once established, the reserve is adjusted as appropriate to reflect any subsequent developments. Actual losses with respect to any such matter may be more or less than the amount estimated by the Corporation. For matters where a loss is not probable, or the amount of the loss cannot be reasonably estimated by the Corporation, no loss reserve is established. In addition, from time to time, the Corporation is involved in investigations or other forms of regulatory or governmental inquiry covering a range of possible issues and, in some cases, these may be part of similar reviews of the specified activities of other companies. These inquiries or investigations could lead to administrative, civil or criminal proceedings involving the Corporation, and could result in fines, penalties, restitution, other types of sanctions, or the need for the Corporation to alter its business, financial or accounting practices. The Corporation’s practice is to cooperate fully with regulatory and governmental inquiries and investigations. As of the date of this report, the Corporation believes that any liabilities, individually or in the aggregate, which may result from the final outcomes of pending legal proceedings, or regulatory or governmental inquiries or investigations, will not have a material adverse effect on the financial condition of the Corporation. However, legal proceedings, inquiries and investigations are often unpredictable, and it is possible that the ultimate resolution of any such matters, if unfavorable, may be material to the Corporation’s results of operations for any particular period, depending, in part, upon the size of the loss or liability imposed and the operating results for the applicable period, and could have a material adverse effect on the Corporation’s business. In addition, regardless of the ultimate outcome of any such legal proceeding, inquiry or investigation, any such matter could cause the Corporation to incur additional expenses, which could be significant, and possibly material, to the Corporation’s results of operations for any particular period. BSA/AML Enforcement Orders The Corporation and two of its bank subsidiaries, Lafayette Ambassador Bank and The Columbia Bank, are subject to regulatory enforcement orders issued during 2014 by their respective federal and state bank regulatory agencies relating to identified deficiencies in the Corporation’s centralized Bank Secrecy Act and anti-money laundering compliance program (the "BSA/AML Compliance Program"), which was designed to comply with the requirements of the Bank Secrecy Act, the USA Patriot Act of 2001 and related anti-money laundering regulations (collectively, the "BSA/AML Requirements"). The regulatory enforcement orders, which are in the form of consent orders or orders to cease and desist issued upon consent ("Consent Orders"), generally require, among other things, that the Corporation and the affected bank subsidiaries undertake a number of required actions to strengthen and enhance the BSA/AML Compliance Program, and, in some cases, conduct retrospective reviews of past account activity and transactions, as well as certain reports filed in accordance with the BSA/AML Requirements, to determine whether suspicious activity and certain transactions in currency were properly identified and reported in accordance with the BSA/AML Requirements. The Corporation and the affected bank subsidiaries have implemented numerous enhancements to the BSA/AML Compliance Program, completed the retrospective reviews required under the Consent Orders, and continue to strengthen and refine the BSA/AML Compliance Program to achieve a sustainable program in accordance with the BSA/AML Requirements. In addition to requiring strengthening and enhancement of the BSA/AML Compliance Program, while the Consent Orders remain in effect, the Corporation and the affected bank subsidiaries are subject to certain restrictions on expansion activities. Further, any failure to comply with the requirements of any of the Consent Orders involving the Corporation or the affected bank subsidiaries could result in further enforcement actions, the imposition of material restrictions on the activities of the Corporation or its bank subsidiaries, or the assessment of fines or penalties. As previously disclosed in a Current Report on Form 8-K filed with the SEC on August 9, 2018, the Federal Deposit Insurance Corporation and the New Jersey Department of Banking and Insurance terminated the Consent Orders those agencies issued on February 25, 2015 to the Corporation’s bank subsidiary, Fulton Bank of New Jersey, relating to deficiencies in the BSA/AML Compliance Program at that bank subsidiary. Fair Lending Investigation During the second quarter of 2015, Fulton Bank, N.A., the Corporation’s largest bank subsidiary, received a letter from the U.S. Department of Justice (the "Department") indicating that the Department had initiated an investigation regarding potential violations of fair lending laws (specifically, the Equal Credit Opportunity Act and the Fair Housing Act) by Fulton Bank, N.A. in certain geographies. Fulton Bank, N.A. has been and is cooperating with the Department and responding to the Department’s requests for information. During the third quarter of 2016, the Department informed the Corporation, Fulton Bank, N.A., and three of the Corporation’s other bank subsidiaries, Fulton Bank of New Jersey, The Columbia Bank and Lafayette Ambassador Bank, that the Department was expanding its investigation of potential lending discrimination on the basis of race and national origin to encompass additional geographies that were not included in the initial letter from the Department. In addition to requesting information concerning the lending activities of these bank subsidiaries, the Department also requested information concerning the Corporation and the residential mortgage lending activities conducted under the Fulton Mortgage Company brand, the trade name used by all of the Corporation’s bank subsidiaries for residential mortgage lending. The investigation relates to lending activities during the period January 1, 2009 to the present. The Corporation and the identified bank subsidiaries are cooperating with the Department and responding to the Department’s requests for information. The Corporation and its bank subsidiaries are not able at this time to determine the terms on which this investigation will be resolved or the timing of such resolution, or to reliably estimate the amounts of any settlement, fines or other penalties or the cost of any other remedial actions, if enforcement action is taken. In addition, should the investigation result in an enforcement action against the Corporation or its bank subsidiaries, or a settlement with the Department, the ability of the Corporation and its bank subsidiaries to engage in certain expansion or other activities may be restricted. SEC Investigation The Corporation is responding to an investigation by the staff of the Division of Enforcement of the SEC regarding certain accounting determinations that could have impacted the Corporation’s reported earnings per share. The Corporation believes that its financial statements filed with the SEC in Forms 10-K and 10-Q present fairly, in all material respects, its financial condition, results of operations and cash flows as of or for the periods ending on their respective dates. The Corporation is cooperating fully with the SEC and at this time cannot predict when or how the investigation will be resolved.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements FASB ASC Topic 820 establishes a fair value hierarchy for the inputs to valuation techniques used to measure assets and liabilities at fair value using the following three categories (from highest to lowest priority): • Level 1 – Inputs that represent quoted prices for identical instruments in active markets. • Level 2 – Inputs that represent quoted prices for similar instruments in active markets, or quoted prices for identical instruments in non-active markets. Also includes valuation techniques whose inputs are derived principally from observable market data other than quoted prices, such as interest rates or other market-corroborated means. • Level 3 – Inputs that are largely unobservable, as little or no market data exists for the instrument being valued. The Corporation has categorized all assets and liabilities measured at fair value on both a recurring and nonrecurring basis into the above three levels. The following tables present summaries of the Corporation’s assets and liabilities measured at fair value on a recurring basis and reported on the consolidated balance sheets: September 30, 2018 Level 1 Level 2 Level 3 Total (in thousands) Loans held for sale $ — $ 27,525 $ — $ 27,525 Available for sale investment securities: U.S. Government sponsored agency securities — 31,091 — 31,091 State and municipal securities — 261,140 — 261,140 Corporate debt securities — 88,940 3,350 92,290 Collateralized mortgage obligations — 797,234 — 797,234 Residential mortgage-backed securities — 478,177 — 478,177 Commercial mortgage-backed securities — 245,751 — 245,751 Auction rate securities — — 103,133 103,133 Total available for sale investment securities — 1,902,333 106,483 2,008,816 Investments held in Rabbi Trust 20,038 — — 20,038 Other assets 530 67,079 — 67,609 Total assets $ 20,568 $ 1,996,937 $ 106,483 $ 2,123,988 Other liabilities $ 20,509 $ 75,031 $ — $ 95,540 December 31, 2017 Level 1 Level 2 Level 3 Total (in thousands) Loans held for sale $ — $ 31,530 $ — $ 31,530 Available for sale investment securities: Equity securities 918 — — 918 U.S. Government sponsored agency securities — 5,938 — 5,938 State and municipal securities — 408,949 — 408,949 Corporate debt securities — 93,552 3,757 97,309 Collateralized mortgage obligations — 602,623 — 602,623 Residential mortgage-backed securities — 1,120,796 — 1,120,796 Commercial mortgage-backed securities — 212,755 — 212,755 Auction rate securities — — 98,668 98,668 Total available for sale investment securities 918 2,444,613 102,425 2,547,956 Investments held in Rabbi Trust 18,982 — — 18,982 Other assets 469 44,539 — 45,008 Total assets $ 20,369 $ 2,520,682 $ 102,425 $ 2,643,476 Other liabilities $ 19,357 $ 39,014 $ — $ 58,371 The valuation techniques used to measure fair value for the items in the preceding tables are as follows: • Mortgage loans held for sale – This category consists of mortgage loans held for sale that the Corporation has elected to measure at fair value. Fair values as of September 30, 2018 and December 31, 2017 were measured based on the price that secondary market investors were offering for loans with similar characteristics. See Note 9, "Derivative Financial Instruments" for details related to the Corporation’s election to measure assets and liabilities at fair value. • Available for sale investment securities – Included in this asset category are both equity and debt securities. Level 2 available for sale debt securities are valued by a third-party pricing service commonly used in the banking industry. The pricing service uses pricing models that vary based on asset class and incorporate available market information, including quoted prices of investment securities with similar characteristics. Because many fixed income securities do not trade on a daily basis, pricing models use available information, as applicable, through processes such as benchmark yield curves, benchmarking of like securities, sector groupings, and matrix pricing. Standard market inputs include: benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers and reference data, including market research publications. For certain security types, additional inputs may be used, or some of the standard market inputs may not be applicable. Management tests the values provided by the pricing service by obtaining securities prices from an alternative third-party source and comparing the results. This test is performed for at least 80% of the securities valued by the pricing service. Generally, differences by security in excess of 5% are researched to reconcile the difference. • Equity securities – As of September 30, 2018 , the Corporation did not hold any equity securities. Equity securities held as of December 31, 2017 consisted of common stocks of financial institutions and other equity investments. These Level 1 investments were measured at fair value based on quoted prices for identical securities in active markets. • U.S. Government sponsored agency securities/State and municipal securities/Collateralized mortgage obligations/Residential mortgage-backed securities/Commercial mortgage-backed securities – These debt securities are classified as Level 2 investments. Fair values are determined by a third-party pricing service, as detailed above. • Corporate debt securities – This category consists of subordinated debt and senior debt issued by financial institutions ( $67.9 million at September 30, 2018 and $61.9 million at December 31, 2017 ), single-issuer trust preferred securities issued by financial institutions ( $19.6 million at September 30, 2018 and $30.7 million at December 31, 2017 ), pooled trust preferred securities issued by financial institutions ( $875,000 at September 30, 2018 and $707,000 at December 31, 2017 ) and other corporate debt issued by non-financial institutions ( $4.0 million at both September 30, 2018 and December 31, 2017 ). Level 2 investments include the Corporation’s holdings of subordinated debt and senior debt, other corporate debt issued by non-financial institutions and $17.0 million and $27.7 million of single-issuer trust preferred securities held at September 30, 2018 and December 31, 2017 , respectively. The fair values for these corporate debt securities are determined by a third-party pricing service, as detailed above. Level 3 investments include the Corporation’s investments in pooled trust preferred securities ( $875,000 at September 30, 2018 and $707,000 at December 31, 2017 ) and certain single-issuer trust preferred securities ( $2.5 million at September 30, 2018 and $3.1 million at December 31, 2017 ). The fair values of these securities were determined based on quotes provided by third-party brokers who determined fair values based predominantly on internal valuation models which were not indicative prices or binding offers. The Corporation’s third-party pricing service cannot derive fair values for these securities primarily due to inactive markets for similar investments. Level 3 values are tested by management primarily through trend analysis, by comparing current values to those reported at the end of the preceding calendar quarter, and determining if they are reasonable based on price and spread movements for this asset class. • Auction rate securities – Due to their illiquidity, ARCs are classified as Level 3 investments and are valued through the use of an expected cash flows model prepared by a third-party valuation expert. The assumptions used in preparing the expected cash flows model include estimates for coupon rates, time to maturity and market rates of return. The most significant unobservable input to the expected cash flows model is an assumed return to market liquidity sometime in the next five years. If the assumed return to market liquidity was lengthened beyond the next five years, this would result in a decrease in the fair value of these ARCs. The Corporation believes that the trusts underlying the ARCs will self-liquidate as student loans are repaid. Level 3 fair values are tested by management through the performance of a trend analysis of the market price and discount rate. Changes in the price and discount rates are compared to changes in market data, including bond ratings, parity ratios, balances and delinquency levels. Investments held in Rabbi Trust - This category consists of mutual funds that are held in trust for employee deferred compensation plans that the Corporation has elected to measure at fair value. Shares of mutual funds are valued based on net asset value, which represent quoted market prices for the underlying shares held in the mutual funds, and as such, are classified as Level 1 and are included in "other assets" on the consolidated balance sheet. Other assets – Included in this category are the following: • Level 1 assets include the fair value of foreign currency exchange contracts ( $529,000 at September 30, 2018 and $460,000 at December 31, 2017 ). The mutual funds and foreign exchange prices used to measure these items at fair value are based on quoted prices for identical instruments in active markets. • Level 2 assets include the fair value of mortgage banking derivatives in the form of interest rate locks and forward commitments with secondary market investors ( $1.4 million at September 30, 2018 and $1.1 million at December 31, 2017 ) and the fair value of interest rate swaps ( $65.7 million at September 30, 2018 and $43.4 million at December 31, 2017 ). The fair values of the Corporation’s interest rate locks, forward commitments and interest rate swaps represent the amounts that would be required to settle the derivative financial instruments at the balance sheet date. See Note 9, "Derivative Financial Instruments," for additional information. Other liabilities – Included in this category are the following: • Level 1 liabilities include employee deferred compensation liabilities which represent amounts due to employees under deferred compensation plans ( $20.0 million at September 30, 2018 and $19.0 million at December 31, 2017 ) and the fair value of foreign currency exchange contracts ( $471,000 at September 30, 2018 and $374,000 at December 31, 2017 ). The fair value of these liabilities are determined in the same manner as the related assets, as described under the heading "Other assets" above. • Level 2 liabilities include the fair value of mortgage banking derivatives in the form of interest rate locks and forward commitments with secondary market investors ( $77,000 at September 30, 2018 and $272,000 at December 31, 2017 ) and the fair value of interest rate swaps ( $75.0 million at September 30, 2018 and $38.7 million at December 31, 2017 ). The fair values of these liabilities are determined in the same manner as the related assets, as described under the heading "Other assets" above. The following table presents the changes in the Corporation’s available for sale investment securities measured at fair value on a recurring basis using unobservable inputs (Level 3): Pooled Trust Single-issuer ARCs Three months ended September 30, 2018 (in thousands) Balance at June 30, 2018 $ 875 $ 3,200 $ 103,122 Realized adjustment to fair value — 71 — Unrealized adjustment to fair value (1) — 153 11 Settlements - calls — (950 ) — Discount accretion (2) — 1 — Balance at September 30, 2018 $ 875 $ 2,475 $ 103,133 Three months ended September 30, 2017 Balance at June 30, 2017 $ 422 $ 2,775 $ 97,923 Unrealized adjustment to fair value (1) — (28 ) 233 Discount accretion (2) — 3 — Balance at September 30, 2017 $ 422 $ 2,750 $ 98,156 Nine months ended September 30, 2018 Balance at December 31, 2017 $ 707 $ 3,050 $ 98,668 Realized adjustment to fair value 71 Unrealized adjustment to fair value (1) 168 297 4,465 Settlements - calls — (950 ) — Discount accretion (2) — 7 — Balance at September 30, 2018 $ 875 $ 2,475 $ 103,133 Nine months ended September 30, 2017 Balance at December 31, 2017 $ 422 $ 2,450 $ 97,256 Unrealized adjustment to fair value (1) — 291 705 Discount accretion (2) — 9 195 Balance at September 30, 2017 $ 422 $ 2,750 $ 98,156 (1) Pooled trust preferred securities, single-issuer trust preferred securities and ARCs are classified as available for sale investment securities; as such, the unrealized adjustment to fair value was recorded as an unrealized holding gain (loss) and included as a component of "available for sale investment securities" on the consolidated balance sheets. (2) Included as a component of "net interest income" on the consolidated statements of income. Certain assets are not measured at fair value on an ongoing basis, but are subject to fair value measurement in certain circumstances, such as upon their acquisition or when there is evidence of impairment. The following table presents the Corporation’s Level 3 financial assets measured at fair value on a nonrecurring basis and reported on the Corporation’s consolidated balance sheets: September 30, 2018 December 31, 2017 (in thousands) Net loans $ 136,024 $ 149,608 OREO 10,684 9,823 MSRs 38,228 37,663 Total assets $ 184,936 $ 197,094 The valuation techniques used to measure fair value for the items in the table above are as follows: • Net loans – This category consists of loans that were collectively evaluated for impairment and have been classified as Level 3 assets. The amount shown is the balance of impaired loans, net of the related allowance for loan losses. See Note 5, "Loans and Allowance for Credit Losses," for additional details. • OREO – This category includes OREO, classified as Level 3 assets. Fair values for OREO were based on estimated selling prices less estimated selling costs for similar assets in active markets. • MSRs – This category includes MSRs, classified as Level 3 assets. MSRs are initially recorded at fair value upon the sale of residential mortgage loans to secondary market investors. MSRs are amortized as a reduction to servicing income over the estimated lives of the underlying loans. MSRs are stratified and evaluated for impairment by comparing each stratum's carrying amount to its estimated fair value. Fair values are determined at the end of each quarter through a discounted cash flows valuation performed by a third-party valuation expert. Significant inputs to the valuation included expected net servicing income, the discount rate and the expected life of the underlying loans. Expected life is based on the contractual terms of the loans, as adjusted for prepayment projections. The weighted average annual constant prepayment rate and the weighted average discount rate used in the September 30, 2018 valuation were 8.8% and 9.0% , respectively. Management tests the reasonableness of the significant inputs to the third-party valuation in comparison to market data. As required by FASB ASC Section 825-10-50, the following table details the book values and estimated fair values of the Corporation’s financial instruments as of September 30, 2018 and December 31, 2017 . In addition, a general description of the methods and assumptions used to estimate such fair values is also provided. September 30, 2018 Amortized Cost Level 1 Level 2 Level 3 Estimated (in thousands) FINANCIAL ASSETS Cash and due from banks $ 90,361 $ 90,361 $ — $ — $ 90,361 Interest-bearing deposits with other banks 322,330 322,330 — — 322,330 Federal Reserve Bank and Federal Home Loan Bank stock 65,926 — 65,926 — 65,926 Loans held for sale 27,525 — 27,525 — 27,525 Securities held to maturity 626,597 622,852 — — 622,852 Available for sale investment securities 2,008,816 — 1,902,333 106,483 2,008,816 Net Loans 15,767,283 — — 15,124,455 15,124,455 Accrued interest receivable 58,584 58,584 — — 58,584 Other financial assets 242,140 126,148 67,079 48,912 242,139 FINANCIAL LIABILITIES Demand and savings deposits $ 13,384,227 $ 13,384,227 $ — $ — $ 13,384,227 Brokered deposits 164,601 164,601 — — 164,601 Time deposits 2,700,186 — 2,684,783 — 2,684,783 Short-term borrowings 485,565 485,565 — — 485,565 Accrued interest payable 11,151 11,151 — — 11,151 Other financial liabilities 251,460 176,429 75,031 — 251,460 Federal Home Loan Bank advances and long-term debt 992,115 — 960,168 — 960,168 December 31, 2017 Amortized Cost Level 1 Level 2 Level 3 Estimated (in thousands) FINANCIAL ASSETS Cash and due from banks $ 108,291 $ 108,291 $ — $ — $ 108,291 Interest-bearing deposits with other banks 293,805 293,805 — — 293,805 Federal Reserve Bank and Federal Home Loan Bank stock 60,761 — 60,761 — 60,761 Loans held for sale 31,530 — 31,530 — 31,530 Available for sale investment securities 2,547,956 918 2,444,613 102,425 2,547,956 Net Loans 15,598,337 — — 15,380,974 15,380,974 Accrued interest receivable 52,910 52,910 — — 52,910 Other financial assets 215,464 123,439 44,539 47,486 215,464 FINANCIAL LIABILITIES Demand and savings deposits $ 13,042,147 $ 13,042,147 $ — $ — $ 13,042,147 Brokered deposits 90,473 90,473 — — 90,473 Time deposits 2,664,912 — 2,664,912 — 2,664,912 Short-term borrowings 617,524 617,524 — — 617,524 Accrued interest payable 9,317 9,317 — — 9,317 Other financial liabilities 227,569 188,555 39,014 — 227,569 Federal Home Loan Bank advances and long-term debt 1,038,346 — 1,038,346 — 1,038,346 Fair values of financial instruments are significantly affected by the assumptions used, principally the timing of future cash flows and discount rates. Because assumptions are inherently subjective in nature, the estimated fair values cannot be substantiated by comparison to independent market quotes and, in many cases, the estimated fair values could not necessarily be realized in an immediate sale or settlement of the instrument. The aggregate fair value amounts presented do not necessarily represent management’s estimate of the underlying value of the Corporation. For short-term financial instruments, defined as those with remaining maturities of 90 days or less, and excluding those recorded at fair value on the Corporation’s consolidated balance sheets, book value was considered to be a reasonable estimate of fair value. The following instruments are predominantly short-term: Assets Liabilities Cash and due from banks Demand and savings deposits Interest-bearing deposits with other banks Short-term borrowings Accrued interest receivable Accrued interest payable Federal Reserve Bank and Federal Home Loan Bank ("FHLB") stock represent restricted investments and are carried at cost on the consolidated balance sheets. As of September 30, 2018, fair values for loans and time deposits were estimated by discounting future cash flows using the current rates, as adjusted for liquidity considerations, at which similar loans would be made to borrowers and similar deposits would be issued to customers for the same remaining maturities. Fair values of loans also include estimated credit losses that would be assumed in a market transaction. Beginning in 2018, fair values estimated in this manner are considered to represent estimated exit prices, required by ASU 2016-01, "Financial Instruments - Overall: Recognition and Measurement of Financial Assets and Financial Liabilities". As of December 31, 2017, loan fair values do not fully incorporate an exit price approach to fair value. The fair values of FHLB advances and long-term debt were estimated by discounting the remaining contractual cash flows using a rate at which the Corporation could issue debt with similar remaining maturities as of the balance sheet date. These borrowings would be categorized in Level 2 liabilities under FASB ASC Topic 820.

Basis of Presentation Basis of

Basis of Presentation Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited consolidated financial statements of Fulton Financial Corporation (the "Corporation") have been prepared in conformity with U.S. generally accepted accounting principles ("U.S. GAAP") for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and notes required by U.S. GAAP for complete financial statements. The preparation of financial statements in accordance with U.S. GAAP requires management to make estimates and assumptions that affect the amounts of assets and liabilities as of the date of the financial statements as well as revenues and expenses during the period. Actual results could differ from those estimates. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation have been included. These consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the notes thereto included in the Corporation's Annual Report on Form 10-K for the year ended December 31, 2017 . Operating results for the three and nine months ended September 30, 2018 are not necessarily indicative of the results that may be expected for the year ending December 31, 2018 . The Corporation evaluates subsequent events through the date of filing of this Form 10-Q with the U.S. Securities and Exchange Commission ("SEC").
Recently Issued Accounting Standards	Recently Adopted Accounting Standards In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Codification ("ASC") Update 2014-09, "Revenue from Contracts with Customers." This standards update established a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. The core principle prescribed by this standards update is that an entity recognizes revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The standard applies to all contracts with customers, except those that are within the scope of other topics in the FASB ASC. The Corporation adopted this standard, and all subsequent Accounting Standards Updates ("ASU") that modified the standard, on January 1, 2018 under the modified retrospective approach with no material impact on its consolidated financial statements. The Corporation evaluated the impact of the adoption of ASC Update 2014-09 on its consolidated financial statements and did not identify any significant changes in the timing of revenue recognition as a result of this amended guidance. The sources of revenue for the Corporation are interest income from loans and investments, net of interest expense on deposits and borrowings, and non-interest income. Non-interest income is earned from various banking and financial services that the Corporation offers through its subsidiary banks. Revenue is recognized as earned based on contractual terms, as transactions occur, or as services are provided. Following is further detail of the various types of revenue the Corporation earns and when it is recognized. Interest income : Interest income is recognized on an accrual basis according to loan agreements, securities contracts or other such written contracts and is outside the scope of ASC Update 2014-09. Investment management and trust services: Consists of trust commission income, brokerage income, money market income and insurance commission income. Trust commission income consists of advisory fees that are based on market values of clients' managed portfolios and transaction fees for fiduciary services performed, both of which are recognized as earned. Brokerage income includes advisory fees which are recognized as earned on a monthly basis and transaction fees that are recognized when transactions occur. Money market income is based on the balances held in trust accounts and is recognized monthly. Insurance commission income is earned and recognized when policies are originated. Currently, no investment management and trust service income is based on performance or investment results. Service charges on deposit accounts: Consists of cash management, overdraft, non-sufficient fund fees and other service charges on deposit accounts. Revenue is primarily transactional and recognized when earned, at the time the transactions occur. Other service charges and fees: Consists of branch fees, automated teller machine fees, debit card income and merchant services fees. These fees are primarily transactional, and revenue is recognized when transactions occur. Also included in other service charges and fees are letter of credit fees, foreign exchange income and commercial loan interest rate swap fees, which are outside the scope of ASC Update 2014-09. Mortgage banking income: Consists of gains or losses on the sale of residential mortgage loans and mortgage loan servicing income. These revenues are outside the scope of ASC Update 2014-09. Other Income: Includes credit card income, gains on sales of Small Business Association ("SBA") loans, cash surrender value of life insurance, and other miscellaneous income. These items are either outside the scope of ASC Update 2014-09 or are immaterial. In January 2016, the FASB issued ASC Update 2016-01, "Financial Instruments - Overall: Recognition and Measurement of Financial Assets and Financial Liabilities." ASC Update 2016-01 provides guidance regarding the income statement impact of equity investments held by an entity and the recognition of changes in fair value of financial liabilities when the fair value option is elected. This standard requires equity investments to be measured at fair value, with changes recorded in net income. This ASU also requires the use of the exit price notion when measuring the fair value of financial instruments for disclosure purposes. ASC Update 2016-01 was effective for interim and annual reporting periods beginning after December 15, 2017. The Corporation adopted this standards update effective with its March 31, 2018 quarterly report on Form 10-Q and the adoption of ASC Update 2016-01 did not have a material impact on its consolidated financial statements. In November 2016, the FASB issued ASC Update 2016-18, "Statement of Cash Flows - Restricted Cash." This standards update provides guidance regarding the presentation of restricted cash in the statement of cash flows. The update requires companies to include amounts generally described as restricted cash and restricted cash equivalents, along with cash and cash equivalents, when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. It also requires an entity to disclose the nature of the restrictions on cash and cash equivalents. ASC Update 2016-18 was effective for interim and annual reporting periods beginning after December 15, 2017. The adoption of ASC Update 2016-18 did not have a material impact on its consolidated financial statements; however, in the second quarter of 2018 on the Consolidated Statements of Cash Flows, the Corporation corrected an error related to the adoption of this standards update to include restricted cash along with cash and cash equivalents in the reconciliation of beginning-of-period and end-of-period total amounts. The change had no impact on net income or retained earnings. In addition, the Corporation will revise the Consolidated Statements of Cash Flows for the three months ended March 31, 2018 when the amounts are next presented in the first quarter of 2019 . In February 2018, the FASB issued ASC Update 2018-02, "Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income." This ASU permits a reclassification from accumulated other comprehensive income ("AOCI") to retained earnings of the stranded tax effects resulting from the application of the Tax Cuts and Jobs Act of 2017 ("Tax Act"), which changed the federal corporate income tax rate from 35% to 21%. This ASU is effective for interim and annual reporting periods beginning after December 15, 2018, with early adoption permitted. The Corporation adopted this standards update effective January 1, 2018 and elected to reclassify $7.1 million of stranded tax effects from AOCI to retained earnings at the beginning of the period of adoption. The Corporation's policy for releasing income tax effects from accumulated other comprehensive income is to release them as investments are sold or mature and as pension and post-retirement liabilities are extinguished. Recently Issued Accounting Standards In February 2016, the FASB issued ASC Update 2016-02, "Leases." ASC Update 2016-02 requires a lessee to recognize for all leases with an initial term greater than twelve months: (1) a “right-of-use” asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term; and (2) a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis. ASC Update 2016-02 is effective for interim and annual reporting periods beginning after December 15, 2018. In July 2018, the FASB also issued amendments to ASC Update 2016-02 (ASC Updates 2018-10 and 2018-11), which allow for an alternative transition method that eliminates the requirement to restate the earliest prior period presented in an entity’s financial statements. Entities that elect this transition method still adopt ASC Update 2016-02 using the modified retrospective transition method, but they recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption rather than in the earliest period presented. The Corporation expects to adopt ASC Update 2016-02 in the first quarter of 2019 using this alternative transition method. The Corporation expects to elect to apply the package of practical expedients permitted within the new standard, which, among other things, allows it to carryforward the historical lease classification, initial direct costs for leases that commenced before the effective date, and the ability to use hindsight in evaluating lessee options to extend or terminate a lease or to purchase the underlying asset. Based on preliminary evaluation, the right-of-use asset and corresponding lease obligation liability, which represents substantially all of the Corporation’s operating lease commitments, is expected to be less than 1% of the Corporation's total assets at adoption. The Corporation does not believe the new lease standard will materially affect its consolidated net income. This estimate is based primarily on the present value of the unpaid future minimum lease payments. The final amount recognized may be impacted by assumptions relating to lease renewals and extensions before the effective date, and the interest rate used to discount those future lease obligations. ASC Update 2016-02 requires lessors to classify leases as a sales-type, direct financing or operating lease. Substantially all of the Corporation's leasing activities as lessor are under direct financing leases and it does not expect the new standard to have a material effect on its financial statements related to these leases and does not expect a significant change in its leasing activities between now and time of adoption. In June 2016, the FASB issued ASC Update 2016-13, "Financial Instruments - Credit Losses." The new impairment model prescribed by this standards update is a single impairment model for all financial assets (i.e., loans and held to maturity investments). The recognition of credit losses would be based on an entity’s current estimate of expected losses (referred to as the Current Expected Credit Loss model, or "CECL"), as opposed to recognition of losses only when they are probable under current U.S. GAAP. ASU 2016-13 also requires new disclosures for financial assets measured at amortized cost, loans and available-for-sale debt securities. Entities will apply the standard's provisions as a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is adopted. This adjustment will also be recognized in regulatory capital. ASC Update 2016-13 is effective for interim and annual reporting periods beginning after December 15, 2019. Early adoption is permitted. The Corporation intends to adopt this standards update effective with its March 31, 2020 quarterly report on Form 10-Q. The Corporation is currently evaluating the impact of the adoption of ASC Update 2016-13 on its consolidated financial statements and disclosures. While the Corporation is currently unable to reasonably estimate the impact of adopting ASU 2016-13, it expects that the impact of adoption could be significantly influenced by the composition, characteristics and quality of its loan portfolio as well as the prevailing economic conditions and forecasts as of the adoption date. The Corporation’s steering committee and working group, which are comprised of individuals from various functional areas, are assessing processes, portfolio segmentation, systems requirements and solutions and resources to implement this new accounting standard. Current activities also include data gathering and building loss models. In addition, the Corporation has engaged a third-party consultant to assist with these implementation efforts. In January 2017, the FASB issued ASC Update 2017-04, "Intangibles - Goodwill and Other." This standards update eliminates Step 2 of the goodwill impairment test which measures the impairment amount. Identifying and measuring impairment will take place in a single quantitative step. In addition, no separate qualitative assessment for reporting units with zero or negative carrying amounts is required. Entities must disclose the existence of these reporting units and the amount of goodwill allocated to them. This update should be applied on a prospective basis, and an entity is required to disclose the nature of and reason for the change in accounting principle upon transition. ASC Update 2017-04 is effective for annual or interim goodwill impairment tests in reporting periods beginning after December 15, 2019. Early adoption is permitted. The Corporation intends to adopt this standards update effective with its 2020 goodwill impairment test and does not expect the adoption of ASC Update 2017-04 to have a material impact on its consolidated financial statements. In March 2017, the FASB issued ASC Update 2017-08, "Premium Amortization on Purchased Callable Debt Securities." This standards update requires that a company amortize the premium on callable debt securities to the earliest call date versus current U.S. GAAP which requires amortization over the contractual life of the securities. The amortization period for callable debt securities purchased at a discount would not be impacted by the new accounting standards update. This amendment is to be adopted on a modified retrospective basis with a cumulative effect adjustment to retained earnings as of the beginning of the period of adoption. ASC Update 2017-08 is effective for annual or interim reporting periods beginning after December 15, 2018. Early adoption is permitted. The Corporation intends to adopt this standards update effective with its March 31, 2019 quarterly report on Form 10-Q and does not expect the adoption of ASC Update 2017-08 to have a material impact on its consolidated financial statements. In August 2018, the FASB issued ASC Update 2018-13, "Fair Value Measurement - Disclosure Framework." This standards update changes the fair value measurement disclosure requirements of ASC 820 "Fair Value Measurement." Among other things, the ASU modifies the disclosure objective paragraphs of ASC 820 to eliminate (1) “at a minimum” from the phrase “an entity shall disclose at a minimum” and (2) other similar “open ended” disclosure requirements to promote the appropriate exercise of discretion by entities. ASC Update 2018-13 is effective for annual or interim reporting periods beginning after December 15, 2019. Early adoption is permitted. The Corporation intends to adopt this standards update effective with its March 31, 2020 quarterly report on Form 10-Q. This standard will impact the Corporation's Fair Value Measurement disclosure but the Corporation does not expect the adoption of ASC Update 2018-13 to have a material impact on its consolidated financial statements. In August 2018, the FASB issued ASC Update 2018-14, "Compensation - Retirement Benefits - Defined Benefit Plans - General." This standards update amends ASC 715-20 to add, remove, and clarify disclosure requirements related to defined benefit pension and other postretirement plans. ASC Update 2018-14 is effective for annual reporting periods beginning after December 15, 2020. Early adoption is permitted. The Corporation intends to adopt this standards update effective with its March 31, 2021 quarterly report on Form 10-Q. This standard will impact the Corporation's disclosure relating to employee benefit plans, but the Corporation does not expect the adoption of ASC Update 2018-14 to have a material impact on its consolidated financial statements. In August 2018, the FASB issued ASC Update 2018-15, "Intangibles - Goodwill and Other - Internal-Use Software." This standards update requires a customer in a cloud computing arrangement that is a service contract to follow the internal-use software guidance in ASC 350-40 to determine which implementation costs to capitalize as assets. ASC Update 2018-15 is effective for annual or interim reporting periods beginning after December 15, 2019. Early adoption is permitted. The Corporation intends to adopt this standards update effective with its March 31, 2020 quarterly report on Form 10-Q and does not expect the adoption of ASC Update 2018-15 to have an impact on its consolidated financial statements. Reclassifications Certain amounts in the 2017 consolidated financial statements and notes have been reclassified to conform to the 2018 presentation. On the Consolidated Statements of Cash Flows, the net change in tax credit investments is presented as cash flows from investing activities. Prior to the quarter ended March 31, 2018, these cash flows were presented as cash flows from operating activities, included in the net increase (decrease) in other liabilities. The presentation of the cash flows for the nine months ended September 30, 2017 was changed to conform to this presentation, resulting in a $21.1 million decrease in net cash flows used in investing activities and a corresponding increase in net cash flows provided by operating activities. The change had no impact on net income or retained earnings. In addition, the Corporation will revise the Consolidated Statements of Cash Flows for each of the comparative 2017 periods in future filings.

Net Income Per Share (Tables)

Net Income Per Share (Tables)	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Reconciliation of Weighted Average Common Shares Outstanding	A reconciliation of weighted average shares outstanding used to calculate basic net income per share and diluted net income per share follows: Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 (in thousands) Weighted average shares outstanding (basic) 175,942 174,991 175,672 174,582 Impact of common stock equivalents 1,186 1,225 1,176 1,194 Weighted average shares outstanding (diluted) 177,128 176,216 176,848 175,776

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income Accumulated Other Comprehensive Income (Tables)	9 Months Ended
	Sep. 30, 2018
Equity [Abstract]
Changes in other comprehensive income	The following table presents changes in other comprehensive (loss) income: Before-Tax Amount Tax Effect Net of Tax Amount (in thousands) Three months ended September 30, 2018 Unrealized loss on securities $ (15,865 ) $ 3,334 $ (12,531 ) Reclassification adjustment for securities gains included in net income (1) (14 ) 3 (11 ) Amortization of net unrealized losses on AFS securities transferred to HTM (2) 1,000 (209 ) 791 Amortization of net unrecognized pension and postretirement items (3) 466 (97 ) 369 Total Other Comprehensive Loss $ (14,413 ) $ 3,031 $ (11,382 ) Three months ended September 30, 2017 Unrealized gain on securities $ 5,109 $ (1,789 ) $ 3,320 Reclassification adjustment for securities gains included in net income (1) (4,597 ) 1,609 (2,988 ) Amortization of net unrecognized pension and postretirement items (3) 523 (183 ) 340 Total Other Comprehensive Income $ 1,035 $ (363 ) $ 672 Nine months ended September 30, 2018 Unrealized loss on securities $ (59,250 ) $ 12,444 $ (46,806 ) Reclassification adjustment for securities gains included in net income (1) (37 ) 7 (30 ) Amortization of net unrealized losses on AFS securities transferred to HTM (2) 1,000 (209 ) 791 Non-credit related unrealized gains on other-than-temporarily impaired debt securities 294 (62 ) 232 Amortization of net unrecognized pension and postretirement items (3) 1,580 (332 ) 1,248 Total Other Comprehensive Loss $ (56,413 ) $ 11,848 $ (44,565 ) Nine months ended September 30, 2017 Unrealized gain on securities $ 27,482 $ (9,621 ) $ 17,861 Reclassification adjustment for securities gains included in net income (1) (7,139 ) 2,500 (4,639 ) Amortization of net unrecognized pension and postretirement items (3) 1,575 (551 ) 1,024 Total Other Comprehensive Income $ 21,918 $ (7,672 ) $ 14,246 (1) Amounts reclassified out of accumulated other comprehensive income. Before-tax amounts included in "Investment securities gains, net" on the consolidated statements of income. See Note 4, "Investment Securities," for additional details. (2) Amounts reclassified out of accumulated other comprehensive income. Before-tax amounts included as a reduction to "Interest Income" on the consolidated statements of income. See Note 4, "Investment Securities," for additional details. (3) Amounts reclassified out of accumulated other comprehensive income. Before-tax amounts included in "Salaries and employee benefits" on the consolidated statements of income. See Note 8, "Employee Benefit Plans," for additional details.
Changes in each component of accumulated other comprehensive income	The following table presents changes in each component of accumulated other comprehensive income (loss), net of tax: Unrealized Gains (Losses) on Investment Securities Not Other-Than-Temporarily Impaired Unrealized Non-Credit Gains (Losses) on Other-Than-Temporarily Impaired Debt Securities Unrecognized Pension and Postretirement Plan Income (Costs) Total (in thousands) Three months ended September 30, 2018 Balance at June 30, 2018 $ (56,690 ) $ 690 $ (17,258 ) $ (73,258 ) Other comprehensive loss before reclassifications (12,531 ) — — (12,531 ) Amounts reclassified from accumulated other comprehensive income (loss) (11 ) — 369 358 Amortization of net unrealized losses on AFS securities transferred to HTM 791 — — 791 Balance at September 30, 2018 $ (68,441 ) $ 690 $ (16,889 ) $ (84,640 ) Three months ended September 30, 2017 Balance at June 30, 2017 $ (10,157 ) $ 273 $ (14,991 ) $ (24,875 ) Other comprehensive income before reclassifications 3,320 — — 3,320 Amounts reclassified from accumulated other comprehensive income (loss) (2,988 ) — 340 (2,648 ) Balance at September 30, 2017 $ (9,825 ) $ 273 $ (14,651 ) $ (24,203 ) Nine months ended September 30, 2018 Balance at December 31, 2017 $ (18,509 ) $ 458 $ (14,923 ) $ (32,974 ) Other comprehensive income before reclassifications (46,806 ) 232 — (46,574 ) Amounts reclassified from accumulated other comprehensive income (loss) (30 ) — 1,248 1,218 Amortization of net unrealized losses on AFS securities transferred to HTM 791 — — 791 Reclassification of stranded tax effects (3,887 ) — (3,214 ) (7,101 ) Balance at September 30, 2018 $ (68,441 ) $ 690 $ (16,889 ) $ (84,640 ) Nine months ended September 30, 2017 Balance at December 31, 2016 $ (23,047 ) $ 273 $ (15,675 ) $ (38,449 ) Other comprehensive income before reclassifications 17,861 — — 17,861 Amounts reclassified from accumulated other comprehensive income (loss) (4,639 ) — 1,024 (3,615 ) Balance at September 30, 2017 $ (9,825 ) $ 273 $ (14,651 ) $ (24,203 )

Investment Securities (Tables)

Investment Securities (Tables)	9 Months Ended
	Sep. 30, 2018
Investments, Debt and Equity Securities [Abstract]
Schedule of Amortized Cost and Fair Values of Investment Securities	The following table presents the amortized cost and estimated fair values of investment securities: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (in thousands) September 30, 2018 Available for Sale U.S. Government sponsored agency securities $ 31,527 $ 1 $ (437 ) $ 31,091 State and municipal securities 269,582 1,281 (9,723 ) 261,140 Corporate debt securities 93,482 950 (2,142 ) 92,290 Collateralized mortgage obligations 820,150 100 (23,016 ) 797,234 Residential mortgage-backed securities 497,614 1,873 (21,310 ) 478,177 Commercial mortgage-backed securities 251,969 — (6,218 ) 245,751 Auction rate securities 107,410 — (4,277 ) 103,133 Total $ 2,071,734 $ 4,205 $ (67,123 ) $ 2,008,816 September 30, 2018 Held to Maturity State and municipal securities $ 156,267 $ — $ (2,006 ) $ 154,261 Residential mortgage-backed securities 470,330 2 (1,741 ) 468,591 Total $ 626,597 $ 2 $ (3,747 ) $ 622,852 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value (in thousands) December 31, 2017 Available for Sale U.S. Government sponsored agency securities $ 5,962 $ 2 $ (26 ) $ 5,938 State and municipal securities 405,860 5,638 (2,549 ) 408,949 Corporate debt securities 96,353 2,832 (1,876 ) 97,309 Collateralized mortgage obligations 611,927 491 (9,795 ) 602,623 Residential mortgage-backed securities 1,132,080 3,957 (15,241 ) 1,120,796 Commercial mortgage-backed securities 215,351 — (2,596 ) 212,755 Auction rate securities 107,410 — (8,742 ) 98,668 Total debt securities 2,574,943 12,920 (40,825 ) 2,547,038 Equity securities 776 142 — 918 Total $ 2,575,719 $ 13,062 $ (40,825 ) $ 2,547,956
Schedule of Amortized Cost and Fair Values of Debt Securities by Contractual Maturities	The amortized cost and estimated fair values of debt securities as of September 30, 2018 , by contractual maturity, are shown in the following table. Actual maturities may differ from contractual maturities as certain investment securities are subject to call or prepayment with or without call or prepayment penalties. Available for Sale Held to Maturity Amortized Estimated Amortized Estimated (in thousands) Due in one year or less $ 5,946 $ 5,949 $ — $ — Due from one year to five years 52,613 52,541 — — Due from five years to ten years 105,838 104,579 — — Due after ten years 337,604 324,585 156,267 154,261 502,001 487,654 156,267 154,261 Residential mortgage-backed securities (1) 497,614 478,177 470,330 468,591 Commercial mortgage-backed securities (1) 251,969 245,751 — — Collateralized mortgage obligations (1) 820,150 797,234 — — Total $ 2,071,734 $ 2,008,816 $ 626,597 $ 622,852 (1) Maturities for mortgage-backed securities and collateralized mortgage obligations are dependent upon the interest rate environment and prepayments on the underlying loans.
Summary of Gains and Losses from Equity and Debt Securities, and Losses Recognized from Other-than-Temporary Impairment	The following table presents information related to the gross realized gains and losses on the sales of equity and debt securities: Gross Gross Net Gains (Losses) Three months ended September 30, 2018 (in thousands) Equity securities $ — $ — $ — Debt securities 116 (102 ) 14 Total $ 116 $ (102 ) $ 14 Three months ended September 30, 2017 Equity securities $ 4,817 $ — $ 4,817 Debt securities 12 (232 ) (220 ) Total $ 4,829 $ (232 ) $ 4,597 Nine months ended September 30, 2018 Equity securities $ 9 $ — $ 9 Debt securities 1,656 (1,628 ) 28 Total $ 1,665 $ (1,628 ) $ 37 Nine months ended September 30, 2017 Equity securities $ 7,167 $ — $ 7,167 Debt securities 218 (246 ) (28 ) Total $ 7,385 $ (246 ) $ 7,139
Gross Unrealized Losses and Fair Values of Investments by Category and Length of Time in Continuous Unrealized Loss Position	The following table presents the gross unrealized losses and estimated fair values of investments, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, at September 30, 2018 and December 31, 2017: Less than 12 months 12 months or longer Total Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses September 30, 2018 Available for Sale (in thousands) U.S. Government sponsored agency securities $ 30,992 $ (437 ) $ — $ — $ 30,992 $ (437 ) State and municipal securities 112,366 (3,550 ) 73,856 (6,173 ) 186,222 (9,723 ) Corporate debt securities 56,159 (694 ) 22,700 (1,448 ) 78,859 (2,142 ) Collateralized mortgage obligations 620,047 (12,833 ) 168,560 (10,183 ) 788,607 (23,016 ) Residential mortgage-backed securities 105,850 (3,447 ) 329,007 (17,863 ) 434,857 (21,310 ) Commercial mortgage-backed securities 164,993 (3,591 ) 77,302 (2,627 ) 242,295 (6,218 ) Auction rate securities — — 103,133 (4,277 ) 103,133 (4,277 ) Total $ 1,090,407 $ (24,552 ) $ 774,558 $ (42,571 ) $ 1,864,965 $ (67,123 ) September 30, 2018 Held to Maturity State and municipal securities 154,261 (2,006 ) — — 154,261 (2,006 ) Residential mortgage-backed securities 454,544 (1,741 ) — — 454,544 (1,741 ) Total $ 608,805 $ (3,747 ) $ — $ — $ 608,805 $ (3,747 ) Less than 12 months 12 months or longer Total Estimated Unrealized Estimated Unrealized Estimated Unrealized December 31, 2017 Available for Sale (in thousands) U.S. Government sponsored agency securities $ 5,830 $ (26 ) $ — $ — $ 5,830 $ (26 ) State and municipal securities 11,650 (50 ) 118,297 (2,499 ) 129,947 (2,549 ) Corporate debt securities 4,544 (48 ) 32,163 (1,828 ) 36,707 (1,876 ) Collateralized mortgage obligations 303,932 (2,408 ) 187,690 (7,387 ) 491,622 (9,795 ) Residential mortgage-backed securities 511,378 (4,348 ) 500,375 (10,893 ) 1,011,753 (15,241 ) Commercial mortgage-backed securities 190,985 (2,118 ) 21,770 (478 ) 212,755 (2,596 ) Auction rate securities — — 98,668 (8,742 ) 98,668 (8,742 ) Total $ 1,028,319 $ (8,998 ) $ 958,963 $ (31,827 ) $ 1,987,282 $ (40,825 )
Summary of Amortized Cost and Fair Values of Corporate Debt Securities	The following table presents the amortized cost and estimated fair values of corporate debt securities: September 30, 2018 December 31, 2017 Amortized cost Estimated fair value Amortized cost Estimated fair value (in thousands) Single-issuer trust preferred securities $ 20,860 $ 19,596 $ 31,335 $ 30,703 Subordinated debt 56,641 55,774 49,013 49,533 Senior debt 12,025 12,089 12,031 12,392 Pooled trust preferred securities — 875 — 707 Corporate debt securities issued by financial institutions 89,526 88,334 92,379 93,335 Other corporate debt securities 3,956 3,956 3,974 3,974 Available for sale corporate debt securities $ 93,482 $ 92,290 $ 96,353 $ 97,309

Loans and Allowance for Credi_2

Loans and Allowance for Credit Losses (Tables)	9 Months Ended
	Sep. 30, 2018
Receivables [Abstract]
Summary of Gross Loans by Type	Loans, net of unearned income are summarized as follows: September 30, December 31, 2017 (in thousands) Real-estate - commercial mortgage $ 6,337,984 $ 6,364,804 Commercial - industrial, financial and agricultural 4,288,823 4,300,297 Real-estate - residential mortgage 2,173,548 1,954,711 Real-estate - home equity 1,469,152 1,559,719 Real-estate - construction 979,857 1,006,935 Consumer 390,708 313,783 Leasing and other 312,207 291,556 Overdrafts 2,047 4,113 Loans, gross of unearned income 15,954,326 15,795,918 Unearned income (29,233 ) (27,671 ) Loans, net of unearned income $ 15,925,093 $ 15,768,247
Schedule of Allowance for Credit Losses	The following table presents the components of the allowance for credit losses: September 30, December 31, (in thousands) Allowance for loan losses $ 157,810 $ 169,910 Reserve for unfunded lending commitments 10,016 6,174 Allowance for credit losses $ 167,826 $ 176,084
Activity in the Allowance for Credit Losses	The following table presents the activity in the allowance for credit losses: Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 (in thousands) Balance at beginning of period $ 169,247 $ 174,998 $ 176,084 $ 171,325 Loans charged off (6,883 ) (7,795 ) (55,440 ) (25,917 ) Recoveries of loans previously charged off 3,842 2,471 8,475 12,766 Net loans charged off (3,041 ) (5,324 ) (46,965 ) (13,151 ) Provision for credit losses 1,620 5,075 38,707 16,575 Balance at end of period $ 167,826 $ 174,749 $ 167,826 $ 174,749 Included in the provision for credit losses for the nine months ended September 30, 2018 was a $36.8 million provision related to a single, large commercial lending relationship (" Commercial Relationship "). In addition, loans charged off for the same period included a $33.9 million charge-off related to the Commercial Relationship . The Corporation had historically maintained an unallocated allowance for credit losses for factors and conditions that existed at the balance sheet date, but were not specifically identifiable, and to recognize the inherent imprecision in estimating and measuring loss exposure. In the second quarter of 2017, enhancements were made to allow for the impact of these factors and conditions to be quantified in the allowance allocation process. Accordingly, an unallocated allowance for credit losses is no longer necessary. The following table presents the activity in the allowance for loan losses by portfolio segment: Real Estate - Commercial Mortgage Commercial - Industrial, Financial and Agricultural Real Estate - Home Equity Real Estate - Residential Mortgage Real Estate - Construction Consumer Leasing, other and overdrafts Unallocated Total (in thousands) Three months ended September 30, 2018 Balance at June 30, 2018 $ 56,583 $ 59,045 $ 16,247 $ 14,504 $ 5,988 $ 1,699 $ 1,984 $ — $ 156,050 Loans charged off (650 ) (3,541 ) (743 ) (483 ) (212 ) (672 ) (582 ) — (6,883 ) Recoveries of loans previously charged off 928 731 217 317 664 390 595 — 3,842 Net loans charged off 278 (2,810 ) (526 ) (166 ) 452 (282 ) 13 — (3,041 ) Provision for loan losses (1) (2,750 ) (301 ) 2,890 3,774 (961 ) 1,429 720 — 4,801 Balance at September 30, 2018 $ 54,111 $ 55,934 $ 18,611 $ 18,112 $ 5,479 $ 2,846 $ 2,717 $ — $ 157,810 Three months ended September 30, 2017 Balance at June 30, 2017 $ 57,372 $ 67,642 $ 17,456 $ 16,439 $ 9,534 $ 1,794 $ 2,105 $ — $ 172,342 Loans charged off (483 ) (2,714 ) (547 ) (195 ) (2,744 ) (373 ) (739 ) — (7,795 ) Recoveries of loans previously charged off 106 665 252 219 629 193 407 — 2,471 Net loans charged off (377 ) (2,049 ) (295 ) 24 (2,115 ) (180 ) (332 ) — (5,324 ) Provision for loan losses (1) (2,008 ) 5,392 1,297 220 (283 ) 383 226 — 5,227 Balance at September 30, 2017 $ 54,987 $ 70,985 $ 18,458 $ 16,683 $ 7,136 $ 1,997 $ 1,999 $ — $ 172,245 Nine months ended September 30, 2018 Balance at December 31, 2017 $ 58,793 $ 66,280 $ 18,127 $ 16,088 $ 6,620 $ 2,045 $ 1,957 $ — $ 169,910 Loans charged off (1,283 ) (46,178 ) (1,967 ) (1,128 ) (976 ) (2,276 ) (1,632 ) — (55,440 ) Recoveries of loans previously charged off 1,528 2,347 694 520 1,414 1,015 957 — 8,475 Net loans charged off 245 (43,831 ) (1,273 ) (608 ) 438 (1,261 ) (675 ) — (46,965 ) Provision for loan losses (1) (4,927 ) 33,485 1,757 2,632 (1,579 ) 2,062 1,435 — 34,865 Balance at September 30, 2018 $ 54,111 $ 55,934 $ 18,611 $ 18,112 $ 5,479 $ 2,846 $ 2,717 $ — $ 157,810 Nine months ended September 30, 2017 Balance at December 31, 2016 $ 46,842 $ 54,353 $ 26,801 $ 22,929 $ 6,455 $ 3,574 $ 3,192 $ 4,533 $ 168,679 Loans charged off (1,949 ) (13,594 ) (1,837 ) (535 ) (3,765 ) (1,659 ) (2,578 ) — (25,917 ) Recoveries of loans previously charged off 1,490 6,830 604 600 1,550 899 793 — 12,766 Net loans charged off (459 ) (6,764 ) (1,233 ) 65 (2,215 ) (760 ) (1,785 ) — (13,151 ) Provision for loan losses (1) 8,604 23,396 (7,110 ) (6,311 ) 2,896 (817 ) 592 (4,533 ) 16,717 Balance at September 30, 2017 $ 54,987 $ 70,985 $ 18,458 $ 16,683 $ 7,136 $ 1,997 $ 1,999 $ — $ 172,245 (1) The provision for loan losses excluded a $3.2 million decrease and a $3.8 million increase in the reserve for unfunded lending commitments for the three and nine months ended September 30, 2018 , respectively, and a $152,000 and a $142,000 increase in the reserve for unfunded lending commitments for the three and nine months ended September 30, 2017, respectively. These amounts were reclassified to other liabilities on the consolidated balance sheets. The following table presents loans, net of unearned income and their related allowance for loan losses, by portfolio segment: Real Estate - Commercial Mortgage Commercial - Industrial, Financial and Agricultural Real Estate - Home Equity Real Estate - Residential Mortgage Real Estate - Construction Consumer Leasing, other and overdrafts Total (in thousands) Allowance for loan losses at September 30, 2018: Loans collectively evaluated for impairment $ 46,812 $ 47,028 $ 7,856 $ 8,369 $ 4,718 $ 2,841 $ 2,717 $ 120,341 Loans individually evaluated for impairment 7,299 8,906 10,755 9,743 761 5 — 37,469 $ 54,111 $ 55,934 $ 18,611 $ 18,112 $ 5,479 $ 2,846 $ 2,717 $ 157,810 Loans, net of unearned income at September 30, 2018: Loans collectively evaluated for impairment $ 6,290,143 $ 4,235,953 $ 1,444,898 $ 2,133,718 $ 971,167 $ 390,700 $ 285,021 $ 15,751,600 Loans individually evaluated for impairment 47,841 52,870 24,254 39,830 8,690 8 — 173,493 $ 6,337,984 $ 4,288,823 $ 1,469,152 $ 2,173,548 $ 979,857 $ 390,708 $ 285,021 $ 15,925,093 Allowance for loan losses at September 30, 2017: Loans collectively evaluated for impairment $ 47,261 $ 55,486 $ 7,632 $ 6,488 $ 5,702 $ 1,976 $ 1,999 $ 126,544 Loans individually evaluated for impairment 7,726 15,499 10,826 10,195 1,434 21 — 45,701 $ 54,987 $ 70,985 $ 18,458 $ 16,683 $ 7,136 $ 1,997 $ 1,999 $ 172,245 Loans, net of unearned income at September 30, 2017: Loans collectively evaluated for impairment $ 6,228,935 $ 4,162,857 $ 1,543,551 $ 1,845,329 $ 959,584 $ 302,415 $ 257,748 $ 15,300,419 Loans individually evaluated for impairment 46,205 60,218 23,922 42,578 13,524 33 — 186,480 $ 6,275,140 $ 4,223,075 $ 1,567,473 $ 1,887,907 $ 973,108 $ 302,448 $ 257,748 $ 15,486,899
Total Impaired Loans by Class Segment	The following table presents total impaired loans by class segment: September 30, 2018 December 31, 2017 Unpaid Principal Balance Recorded Investment Related Allowance Unpaid Principal Balance Recorded Investment Related Allowance (in thousands) With no related allowance recorded: Real estate - commercial mortgage $ 27,298 $ 25,665 $ — $ 26,728 $ 22,886 $ — Commercial 64,150 33,552 — 44,936 39,550 — Real estate - residential mortgage 3,171 3,170 — 4,575 4,575 — Construction 10,146 6,476 — 12,477 8,100 — 104,765 68,863 — 88,716 75,111 — With a related allowance recorded: Real estate - commercial mortgage 28,584 22,176 7,299 33,710 25,895 8,112 Commercial 24,530 19,318 8,906 29,816 24,175 11,406 Real estate - home equity 27,731 24,254 10,755 28,282 24,693 11,124 Real estate - residential mortgage 41,772 36,660 9,743 42,597 37,132 9,895 Construction 5,874 2,214 761 7,308 4,097 967 Consumer 8 8 5 26 26 17 128,499 104,630 37,469 141,739 116,018 41,521 Total $ 233,264 $ 173,493 $ 37,469 $ 230,455 $ 191,129 $ 41,521 As of September 30, 2018 and December 31, 2017 , there were $68.9 million and $75.1 million , respectively, of impaired loans that did not have a related allowance for loan loss. The estimated fair values of the collateral securing these loans exceeded their carrying amount, or the loans were previously charged down to realizable collateral values. Accordingly, no specific valuation allowance was considered to be necessary. The following table presents average impaired loans by class segment: Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 Average Interest Average Interest Average Interest Average Interest (in thousands) With no related allowance recorded: Real estate - commercial mortgage $ 26,051 $ 94 $ 21,698 $ 72 $ 25,702 $ 274 $ 22,770 $ 213 Commercial 30,157 66 33,044 46 35,098 208 29,309 128 Real estate - residential mortgage 3,182 20 4,616 27 3,872 71 4,645 79 Construction 6,845 — 9,042 5 7,408 — 7,043 11 66,235 180 68,400 150 72,080 553 63,767 431 With a related allowance recorded: Real estate - commercial mortgage 23,734 85 25,910 86 24,727 260 27,518 259 Commercial 23,687 51 25,152 34 23,934 149 24,097 97 Real estate - home equity 24,628 202 22,837 150 24,690 581 20,957 362 Real estate - residential mortgage 36,396 227 38,329 225 36,578 671 39,584 680 Construction 2,061 — 6,251 4 2,778 — 6,677 11 Consumer 10 — 34 — 18 — 36 — Leasing, other and overdrafts — — — — — — 356 — 110,516 565 118,513 499 112,725 1,661 119,225 1,409 Total $ 176,751 $ 745 $ 186,913 $ 649 $ 184,805 $ 2,214 $ 182,992 $ 1,840 (1) All impaired loans, excluding accruing TDRs, were non-accrual loans. Interest income recognized for the three and nine months ended September 30, 2018 and 2017 represents amounts earned on accruing TDRs.
Financing Receivable Credit Quality Indicators	The following table presents a summary of performing, delinquent and non-performing loans for the indicated loan class segments: Performing Delinquent (1) Non-performing (2) Total September 30, 2018 December 31, 2017 September 30, 2018 December 31, 2017 September 30, 2018 December 31, 2017 September 30, 2018 December 31, 2017 (dollars in thousands) Real estate - home equity $ 1,447,184 $ 1,535,557 $ 11,886 $ 12,655 $ 10,082 $ 11,507 $ 1,469,152 $ 1,559,719 Real estate - residential mortgage 2,131,239 1,914,888 23,233 18,852 19,076 20,971 2,173,548 1,954,711 Construction - other 82,417 77,403 — 203 490 411 82,907 78,017 Consumer - direct 58,259 54,828 311 315 60 70 58,630 55,213 Consumer - indirect 328,423 254,663 3,435 3,681 220 226 332,078 258,570 Total consumer 386,682 309,491 3,746 3,996 280 296 390,708 313,783 Leasing, other and overdrafts 282,812 267,111 2,119 855 90 32 285,021 267,998 $ 4,330,334 $ 4,104,450 $ 40,984 $ 36,561 $ 30,018 $ 33,217 $ 4,401,336 $ 4,174,228 % of Total 98.4 % 98.3 % 0.9 % 0.9 % 0.7 % 0.8 % 100.0 % 100.0 % (1) Includes all accruing loans 30 days to 89 days past due. (2) Includes all accruing loans 90 days or more past due and all non-accrual loans. The following table presents internal credit risk ratings for the indicated loan class segments: Pass Special Mention Substandard or Lower Total September 30, 2018 December 31, 2017 September 30, 2018 December 31, 2017 September 30, 2018 December 31, 2017 September 30, 2018 December 31, 2017 (dollars in thousands) Real estate - commercial mortgage $ 6,032,828 $ 6,066,396 $ 170,362 $ 147,604 $ 134,794 $ 150,804 $ 6,337,984 $ 6,364,804 Commercial - secured 3,839,283 3,831,485 150,310 121,842 138,604 179,113 4,128,197 4,132,440 Commercial - unsecured 152,796 159,620 3,898 5,478 3,932 2,759 160,626 167,857 Total commercial - industrial, financial and agricultural 3,992,079 3,991,105 154,208 127,320 142,536 181,872 4,288,823 4,300,297 Construction - commercial residential 120,249 143,759 7,677 5,259 8,379 14,084 136,305 163,102 Construction - commercial 756,477 761,218 552 846 3,616 3,752 760,645 765,816 Total construction (excluding Construction - other) 876,726 904,977 8,229 6,105 11,995 17,836 896,950 928,918 $ 10,901,633 $ 10,962,478 $ 332,799 $ 281,029 $ 289,325 $ 350,512 $ 11,523,757 $ 11,594,019 % of Total 94.6 % 94.6 % 2.9 % 2.4 % 2.5 % 3.0 % 100.0 % 100.0 %
Non-Performing Assets	The following table presents non-performing assets: September 30, December 31, (in thousands) Non-accrual loans $ 106,433 $ 124,749 Loans 90 days or more past due and still accruing 13,663 10,010 Total non-performing loans 120,096 134,759 Other real estate owned (OREO) 10,684 9,823 Total non-performing assets $ 130,780 $ 144,582
Past due Loan Status and Non-Accrual Loans by Portfolio Segment	The following tables present past due status and non-accrual loans by portfolio segment and class segment: September 30, 2018 30-59 Days Past Due 60-89 Days Past Due ≥ 90 Days Past Due and Accruing Non- accrual Total ≥ 90 Days Total Past Due Current Total (in thousands) Real estate - commercial mortgage $ 12,129 $ 1,599 $ 5,242 $ 32,151 $ 37,393 $ 51,121 $ 6,286,863 $ 6,337,984 Commercial - secured 6,705 1,218 835 41,327 42,162 50,085 4,078,112 4,128,197 Commercial - unsecured 357 437 29 1,200 1,229 2,023 158,603 160,626 Total commercial - industrial, financial and agricultural 7,062 1,655 864 42,527 43,391 52,108 4,236,715 4,288,823 Real estate - home equity 9,383 2,503 2,037 8,045 10,082 21,968 1,447,184 1,469,152 Real estate - residential mortgage 17,731 5,502 4,056 15,020 19,076 42,309 2,131,239 2,173,548 Construction - commercial residential 157 225 896 8,379 9,275 9,657 126,648 136,305 Construction - commercial — — — 19 19 19 760,626 760,645 Construction - other — — 198 292 490 490 82,417 82,907 Total real estate - construction 157 225 1,094 8,690 9,784 10,166 969,691 979,857 Consumer - direct 225 86 60 — 60 371 58,259 58,630 Consumer - indirect 2,903 532 220 — 220 3,655 328,423 332,078 Total consumer 3,128 618 280 — 280 4,026 386,682 390,708 Leasing, other and overdrafts 1,739 380 90 — 90 2,209 282,812 285,021 Total $ 51,329 $ 12,482 $ 13,663 $ 106,433 $ 120,096 $ 183,907 $ 15,741,186 $ 15,925,093 December 31, 2017 30-59 Days Past Due 60-89 Days Past Due ≥ 90 Days Past Due and Accruing Non- accrual Total ≥ 90 Days Total Past Due Current Total (in thousands) Real estate - commercial mortgage $ 9,456 $ 4,223 $ 625 $ 34,822 $ 35,447 $ 49,126 $ 6,315,678 $ 6,364,804 Commercial - secured 4,778 5,254 1,360 52,255 53,615 63,647 4,068,793 4,132,440 Commercial - unsecured 305 10 45 649 694 1,009 166,848 167,857 Total commercial - industrial, financial and agricultural 5,083 5,264 1,405 52,904 54,309 64,656 4,235,641 4,300,297 Real estate - home equity 9,640 3,015 2,372 9,135 11,507 24,162 1,535,557 1,559,719 Real estate - residential mortgage 11,961 6,891 5,280 15,691 20,971 39,823 1,914,888 1,954,711 Construction - commercial residential — 439 — 11,767 11,767 12,206 150,896 163,102 Construction - commercial 483 — — 19 19 502 765,314 765,816 Construction - other 203 — — 411 411 614 77,403 78,017 Total real estate - construction 686 439 — 12,197 12,197 13,322 993,613 1,006,935 Consumer - direct 260 55 70 — 70 385 54,828 55,213 Consumer - indirect 3,055 626 226 — 226 3,907 254,663 258,570 Total consumer 3,315 681 296 — 296 4,292 309,491 313,783 Leasing, other and overdrafts 568 287 32 — 32 887 267,111 267,998 Total $ 40,709 $ 20,800 $ 10,010 $ 124,749 $ 134,759 $ 196,268 $ 15,571,979 $ 15,768,247
Troubled Debt Restructurings on Financing Receivables	The following table presents TDRs, by class segment: September 30, December 31, (in thousands) Real-estate - residential mortgage $ 24,810 $ 26,016 Real-estate - commercial mortgage 15,690 13,959 Real estate - home equity 16,208 15,558 Commercial 10,342 10,820 Consumer 8 26 Total accruing TDRs 67,058 66,379 Non-accrual TDRs (1) 23,238 29,051 Total TDRs $ 90,296 $ 95,430 (1) Included in non-accrual loans in the preceding table detailing non-performing assets
Loan Terms Modified Under Troubled Debt Restructurings	The following table presents TDRs, by class segment and type of concession for loans that were modified during the three and nine months ended September 30, 2018 and 2017 : Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 Number of Loans Post-Modification Recorded Investment Number of Loans Post-Modification Recorded Investment Number of Loans Post-Modification Recorded Investment Number of Loans Post-Modification Recorded Investment (dollars in thousands) Real estate – residential mortgage: Extend maturity with rate concession 3 $ 330 2 $ 468 3 $ 330 2 $ 468 Extend maturity without rate concession 1 267 2 151 2 344 4 488 Bankruptcy — — — — 1 5 2 335 Real estate - commercial mortgage: Extend maturity without rate concession — — 2 1,247 6 8,261 6 2,228 Bankruptcy — — — — — — 1 12 Real estate - home equity: Extend maturity without rate concession 23 985 14 1,315 63 3,607 47 3,874 Bankruptcy 1 17 6 127 8 438 23 1,643 Commercial: Extend maturity without rate concession 2 913 1 160 7 2,064 9 5,853 Bankruptcy — — — — — — 1 490 Commercial – unsecured: Extend maturity without rate concession — — — — — — 1 33 Construction - commercial residential: Extend maturity without rate concession — — — — — — 1 1,204 Total 30 $ 2,512 27 $ 3,468 90 $ 15,049 97 $ 16,628 The following table presents TDRs, by class segment, as of September 30, 2018 and 2017 that were modified in the previous 12 months and had a post-modification payment default during the nine months ended September 30, 2018 and 2017 . The Corporation defines a payment default as a single missed payment. 2018 2017 Number of Loans Recorded Investment Number of Loans Recorded Investment (dollars in thousands) Real estate - residential mortgage 6 $ 724 5 $ 1,321 Real estate - commercial mortgage 2 452 3 653 Real estate - home equity 25 1,591 27 1,598 Commercial 4 5,042 2 264 Construction — — 2 1,609 Total 37 $ 7,809 39 $ 5,445

Mortgage Servicing Rights (Tabl

Mortgage Servicing Rights (Tables)	9 Months Ended
	Sep. 30, 2018
Transfers and Servicing [Abstract]
Summary of Changes in Mortgage Servicing Rights	The following table summarizes the changes in mortgage servicing rights ("MSRs"), which are included in other assets on the consolidated balance sheets: Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 (in thousands) Amortized cost: Balance at beginning of period $ 37,894 $ 38,180 $ 37,663 $ 38,822 Originations of mortgage servicing rights 2,018 1,333 5,247 3,719 Amortization (1,684 ) (1,639 ) (4,682 ) (4,667 ) Balance at end of period $ 38,228 $ 37,874 $ 38,228 $ 37,874 Valuation allowance: Balance at beginning of period $ — $ — $ — $ (1,291 ) Reductions to valuation allowance — — — 1,291 Balance at end of period $ — $ — $ — $ — Net MSRs at end of period $ 38,228 $ 37,874 $ 38,228 $ 37,874

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Compensation Expense and Related Tax Benefits	The following table presents compensation expense and the related tax benefits for equity awards recognized in the consolidated statements of income: Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 (in thousands) Compensation expense $ 1,823 $ 1,570 $ 6,007 $ 3,339 Tax benefit (492 ) (628 ) (2,028 ) (3,312 ) Stock-based compensation expense, net of tax benefit $ 1,331 $ 942 $ 3,979 $ 27

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	9 Months Ended
	Sep. 30, 2018
Retirement Benefits [Abstract]
Schedule of Defined Benefit Plans Disclosures	The components of the net benefit for the Corporation’s Postretirement Benefits Plan ("Postretirement Plan") consisted of the following components: Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 (in thousands) Interest cost $ 13 $ 17 $ 42 $ 51 Net accretion and deferral (139 ) (141 ) (419 ) (423 ) Net periodic benefit $ (126 ) $ (124 ) $ (377 ) $ (372 ) The net periodic pension cost for the Corporation’s Defined Benefit Pension Plan ("Pension Plan") consisted of the following components: Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 (in thousands) Interest cost $ 763 $ 830 $ 2,290 $ 2,490 Expected return on plan assets (512 ) (451 ) (1,536 ) (1,353 ) Net amortization and deferral 607 663 1,822 1,989 Net periodic pension cost $ 858 $ 1,042 $ 2,576 $ 3,126

Derivative Financial Instrume_2

Derivative Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Summary of Notional Amounts and Fair Values of Derivative Financial Instruments	The following table presents a summary of the notional amounts and fair values of derivative financial instruments: September 30, 2018 December 31, 2017 Notional Asset Notional Asset (in thousands) Interest Rate Locks with Customers Positive fair values $ 143,869 $ 904 $ 129,469 $ 1,059 Negative fair values 11,535 (77 ) 8,957 (59 ) Net interest rate locks with customers 827 1,000 Forward Commitments Positive fair values 122,856 480 3,856 34 Negative fair values — — 100,808 (213 ) Net forward commitments 480 (179 ) Interest Rate Swaps with Customers Positive fair values 548,277 6,922 1,316,548 24,505 Negative fair values 1,882,655 (71,175 ) 716,634 (18,978 ) Net interest rate swaps with customers (64,253 ) 5,527 Interest Rate Swaps with Dealer Counterparties Positive fair values (1) (3) 1,882,655 58,773 716,634 18,941 Negative fair values (2) (3) 548,277 (3,778 ) 1,316,548 (19,764 ) Net interest rate swaps with dealer counterparties 54,995 (823 ) Foreign Exchange Contracts with Customers Positive fair values 8,797 193 4,852 276 Negative fair values 9,176 (277 ) 5,914 (119 ) Net foreign exchange contracts with customers (84 ) 157 Foreign Exchange Contracts with Correspondent Banks Positive fair values 10,506 325 7,960 184 Negative fair values 9,239 (192 ) 6,048 (255 ) Net foreign exchange contracts with correspondent banks 133 (71 ) Net derivative fair value asset $ (7,902 ) $ 5,611 (1) Includes centrally cleared interest rate swaps with a notional amount of $416.1 million and a fair value of $0 as of September 30, 2018 and a notional amount of $24.4 million and a fair value of $0 as of December 31, 2017 . (2) Includes centrally cleared interest rate swaps with a notional amount of $249.7 million and a fair value of $0 as of September 30, 2018 and a notional amount of $377.1 million and a fair value of $0 as of December 31, 2017 . (3) The variation margin posted as collateral on centrally cleared interest rate swaps, which represents the fair value of such swaps, is legally characterized as settlements of the outstanding derivative contracts instead of cash collateral. Accordingly, the fair values of centrally cleared interest rate swaps were offset by variation margins of $9.3 million at September 30, 2018 , increasing the fair value of such swaps to $0 , and $4.6 million at December 31, 2017 , reducing the fair value of such swaps to $0 .
Summary of Fair Value Gains and Losses on Derivative Financial Instruments	The following table presents a summary of the fair value (losses) gains on derivative financial instruments: Three months ended September 30 Nine months ended September 30 2018 2017 2018 2017 (in thousands) Interest rate locks with customers $ (533 ) $ (59 ) $ (173 ) $ 631 Forward commitments 974 (48 ) 659 (2,270 ) Interest rate swaps with customers (14,763 ) (47 ) (69,780 ) 12,947 Interest rate swaps with dealer counterparties (1) 11,193 1,248 55,818 (6,582 ) Foreign exchange contracts with customers (225 ) 140 (241 ) (177 ) Foreign exchange contracts with correspondent banks 166 (111 ) 204 219 Net fair value (losses) gains on derivative financial instruments $ (3,188 ) $ 1,123 $ (13,513 ) $ 4,768 (1) Not included is $3.6 million and $13.9 million , respectively, of gains representing the change in the variation margin for the three and nine months ended September 30, 2018 and $1.2 million and $6.3 million , respectively, of losses representing the change in the variation margin for the three and nine months ended September 30, 2017 .
Summary of Corporation's Mortgage Loans Held for Sale	The following table presents a summary of the Corporation’s mortgage loans held for sale: September 30, December 31, (in thousands) Cost (1) $ 27,271 $ 31,069 Fair value 27,525 31,530 (1) Cost basis of mortgage loans held for sale represents the unpaid principal balance.
Summary of Offsetting Derivative Assets	The following table presents the Corporation's financial instruments that are eligible for offset, and the effects of offsetting, on the consolidated balance sheets: Gross Amounts Gross Amounts Not Offset Recognized on the Consolidated on the Balance Sheets Consolidated Financial Cash Net Balance Sheets Instruments (1) Collateral (2) Amount (in thousands) September 30, 2018 Interest rate swap derivative assets $ 65,695 $ (4,662 ) $ (56,630 ) $ 4,403 Foreign exchange derivative assets with correspondent banks 325 (192 ) — 133 Total $ 66,020 $ (4,854 ) $ (56,630 ) $ 4,536 Interest rate swap derivative liabilities $ 74,954 $ (4,662 ) $ (13,628 ) $ 56,664 Foreign exchange derivative liabilities with correspondent banks 192 (192 ) — — Total $ 75,146 $ (4,854 ) $ (13,628 ) $ 56,664 December 31, 2017 Interest rate swap derivative assets $ 43,446 $ (16,844 ) $ — $ 26,602 Foreign exchange derivative assets with correspondent banks 184 (184 ) — — Total $ 43,630 $ (17,028 ) $ — $ 26,602 Interest rate swap derivative liabilities $ 38,742 $ (16,844 ) $ (6,588 ) $ 15,310 Foreign exchange derivative liabilities with correspondent banks 255 (184 ) — 71 Total $ 38,997 $ (17,028 ) $ (6,588 ) $ 15,381 (1) For interest rate swap assets, amounts represent any derivative liability fair values that could be offset in the event of counterparty or customer default. For interest rate swap liabilities, amounts represent any derivative asset fair values that could be offset in the event of counterparty or customer default. (2) Amounts represent cash collateral received from the counterparty or posted by the Corporation on interest rate swap transactions and foreign exchange contracts with financial institution counterparties. Interest rate swaps with customers are collateralized by the same collateral securing the underlying loans to those borrowers. Cash and securities collateral amounts are included in the table only to the extent of the net derivative fair values.
Summary of Offsetting Derivative Liabilities	The following table presents the Corporation's financial instruments that are eligible for offset, and the effects of offsetting, on the consolidated balance sheets: Gross Amounts Gross Amounts Not Offset Recognized on the Consolidated on the Balance Sheets Consolidated Financial Cash Net Balance Sheets Instruments (1) Collateral (2) Amount (in thousands) September 30, 2018 Interest rate swap derivative assets $ 65,695 $ (4,662 ) $ (56,630 ) $ 4,403 Foreign exchange derivative assets with correspondent banks 325 (192 ) — 133 Total $ 66,020 $ (4,854 ) $ (56,630 ) $ 4,536 Interest rate swap derivative liabilities $ 74,954 $ (4,662 ) $ (13,628 ) $ 56,664 Foreign exchange derivative liabilities with correspondent banks 192 (192 ) — — Total $ 75,146 $ (4,854 ) $ (13,628 ) $ 56,664 December 31, 2017 Interest rate swap derivative assets $ 43,446 $ (16,844 ) $ — $ 26,602 Foreign exchange derivative assets with correspondent banks 184 (184 ) — — Total $ 43,630 $ (17,028 ) $ — $ 26,602 Interest rate swap derivative liabilities $ 38,742 $ (16,844 ) $ (6,588 ) $ 15,310 Foreign exchange derivative liabilities with correspondent banks 255 (184 ) — 71 Total $ 38,997 $ (17,028 ) $ (6,588 ) $ 15,381 (1) For interest rate swap assets, amounts represent any derivative liability fair values that could be offset in the event of counterparty or customer default. For interest rate swap liabilities, amounts represent any derivative asset fair values that could be offset in the event of counterparty or customer default. (2) Amounts represent cash collateral received from the counterparty or posted by the Corporation on interest rate swap transactions and foreign exchange contracts with financial institution counterparties. Interest rate swaps with customers are collateralized by the same collateral securing the underlying loans to those borrowers. Cash and securities collateral amounts are included in the table only to the extent of the net derivative fair values.

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Summary of Outstanding Commitments to Extend Credit and Letters of Credit	The outstanding amounts of commitments to extend credit and letters of credit were as follows: September 30, December 31, 2017 (in thousands) Commitments to extend credit $ 6,562,515 $ 6,205,029 Standby letters of credit 325,386 326,973 Commercial letters of credit 42,285 41,801

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following tables present summaries of the Corporation’s assets and liabilities measured at fair value on a recurring basis and reported on the consolidated balance sheets: September 30, 2018 Level 1 Level 2 Level 3 Total (in thousands) Loans held for sale $ — $ 27,525 $ — $ 27,525 Available for sale investment securities: U.S. Government sponsored agency securities — 31,091 — 31,091 State and municipal securities — 261,140 — 261,140 Corporate debt securities — 88,940 3,350 92,290 Collateralized mortgage obligations — 797,234 — 797,234 Residential mortgage-backed securities — 478,177 — 478,177 Commercial mortgage-backed securities — 245,751 — 245,751 Auction rate securities — — 103,133 103,133 Total available for sale investment securities — 1,902,333 106,483 2,008,816 Investments held in Rabbi Trust 20,038 — — 20,038 Other assets 530 67,079 — 67,609 Total assets $ 20,568 $ 1,996,937 $ 106,483 $ 2,123,988 Other liabilities $ 20,509 $ 75,031 $ — $ 95,540 December 31, 2017 Level 1 Level 2 Level 3 Total (in thousands) Loans held for sale $ — $ 31,530 $ — $ 31,530 Available for sale investment securities: Equity securities 918 — — 918 U.S. Government sponsored agency securities — 5,938 — 5,938 State and municipal securities — 408,949 — 408,949 Corporate debt securities — 93,552 3,757 97,309 Collateralized mortgage obligations — 602,623 — 602,623 Residential mortgage-backed securities — 1,120,796 — 1,120,796 Commercial mortgage-backed securities — 212,755 — 212,755 Auction rate securities — — 98,668 98,668 Total available for sale investment securities 918 2,444,613 102,425 2,547,956 Investments held in Rabbi Trust 18,982 — — 18,982 Other assets 469 44,539 — 45,008 Total assets $ 20,369 $ 2,520,682 $ 102,425 $ 2,643,476 Other liabilities $ 19,357 $ 39,014 $ — $ 58,371
Schedule of Changes in Assets and Liabilities Measured at Fair Value on a Recurring Basis using Level 3 Inputs	The following table presents the changes in the Corporation’s available for sale investment securities measured at fair value on a recurring basis using unobservable inputs (Level 3): Pooled Trust Single-issuer ARCs Three months ended September 30, 2018 (in thousands) Balance at June 30, 2018 $ 875 $ 3,200 $ 103,122 Realized adjustment to fair value — 71 — Unrealized adjustment to fair value (1) — 153 11 Settlements - calls — (950 ) — Discount accretion (2) — 1 — Balance at September 30, 2018 $ 875 $ 2,475 $ 103,133 Three months ended September 30, 2017 Balance at June 30, 2017 $ 422 $ 2,775 $ 97,923 Unrealized adjustment to fair value (1) — (28 ) 233 Discount accretion (2) — 3 — Balance at September 30, 2017 $ 422 $ 2,750 $ 98,156 Nine months ended September 30, 2018 Balance at December 31, 2017 $ 707 $ 3,050 $ 98,668 Realized adjustment to fair value 71 Unrealized adjustment to fair value (1) 168 297 4,465 Settlements - calls — (950 ) — Discount accretion (2) — 7 — Balance at September 30, 2018 $ 875 $ 2,475 $ 103,133 Nine months ended September 30, 2017 Balance at December 31, 2017 $ 422 $ 2,450 $ 97,256 Unrealized adjustment to fair value (1) — 291 705 Discount accretion (2) — 9 195 Balance at September 30, 2017 $ 422 $ 2,750 $ 98,156 (1) Pooled trust preferred securities, single-issuer trust preferred securities and ARCs are classified as available for sale investment securities; as such, the unrealized adjustment to fair value was recorded as an unrealized holding gain (loss) and included as a component of "available for sale investment securities" on the consolidated balance sheets. (2) Included as a component of "net interest income" on the consolidated statements of income.
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis	The following table presents the Corporation’s Level 3 financial assets measured at fair value on a nonrecurring basis and reported on the Corporation’s consolidated balance sheets: September 30, 2018 December 31, 2017 (in thousands) Net loans $ 136,024 $ 149,608 OREO 10,684 9,823 MSRs 38,228 37,663 Total assets $ 184,936 $ 197,094
Details of Book Value and Fair Value of Financial Instruments	As required by FASB ASC Section 825-10-50, the following table details the book values and estimated fair values of the Corporation’s financial instruments as of September 30, 2018 and December 31, 2017 . In addition, a general description of the methods and assumptions used to estimate such fair values is also provided. September 30, 2018 Amortized Cost Level 1 Level 2 Level 3 Estimated (in thousands) FINANCIAL ASSETS Cash and due from banks $ 90,361 $ 90,361 $ — $ — $ 90,361 Interest-bearing deposits with other banks 322,330 322,330 — — 322,330 Federal Reserve Bank and Federal Home Loan Bank stock 65,926 — 65,926 — 65,926 Loans held for sale 27,525 — 27,525 — 27,525 Securities held to maturity 626,597 622,852 — — 622,852 Available for sale investment securities 2,008,816 — 1,902,333 106,483 2,008,816 Net Loans 15,767,283 — — 15,124,455 15,124,455 Accrued interest receivable 58,584 58,584 — — 58,584 Other financial assets 242,140 126,148 67,079 48,912 242,139 FINANCIAL LIABILITIES Demand and savings deposits $ 13,384,227 $ 13,384,227 $ — $ — $ 13,384,227 Brokered deposits 164,601 164,601 — — 164,601 Time deposits 2,700,186 — 2,684,783 — 2,684,783 Short-term borrowings 485,565 485,565 — — 485,565 Accrued interest payable 11,151 11,151 — — 11,151 Other financial liabilities 251,460 176,429 75,031 — 251,460 Federal Home Loan Bank advances and long-term debt 992,115 — 960,168 — 960,168 December 31, 2017 Amortized Cost Level 1 Level 2 Level 3 Estimated (in thousands) FINANCIAL ASSETS Cash and due from banks $ 108,291 $ 108,291 $ — $ — $ 108,291 Interest-bearing deposits with other banks 293,805 293,805 — — 293,805 Federal Reserve Bank and Federal Home Loan Bank stock 60,761 — 60,761 — 60,761 Loans held for sale 31,530 — 31,530 — 31,530 Available for sale investment securities 2,547,956 918 2,444,613 102,425 2,547,956 Net Loans 15,598,337 — — 15,380,974 15,380,974 Accrued interest receivable 52,910 52,910 — — 52,910 Other financial assets 215,464 123,439 44,539 47,486 215,464 FINANCIAL LIABILITIES Demand and savings deposits $ 13,042,147 $ 13,042,147 $ — $ — $ 13,042,147 Brokered deposits 90,473 90,473 — — 90,473 Time deposits 2,664,912 — 2,664,912 — 2,664,912 Short-term borrowings 617,524 617,524 — — 617,524 Accrued interest payable 9,317 9,317 — — 9,317 Other financial liabilities 227,569 188,555 39,014 — 227,569 Federal Home Loan Bank advances and long-term debt 1,038,346 — 1,038,346 — 1,038,346

Basis of Presentation Narrative

Basis of Presentation Narrative (Details) - USD ($) $ in Thousands		Jan. 01, 2018	Sep. 30, 2018	Sep. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of stranded tax effects	[1]		$ 0
Decrease in net cash flows used in investing activities			478,766	$ 1,202,312
Increase in net cash provided by operating activities			$ 232,691	215,531
Accounting Standards Update 2018-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of stranded tax effects		$ 7,100
Restatement Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase in net cash provided by operating activities				$ 12,700
[1]	Result of adoption of ASU 2018-02, See Note 1 to Consolidated Financial Statements for further details.

Net Income Per Share Reconcilia

Net Income Per Share Reconciliation of Weighted Average Common Shares Outstanding (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Weighted average shares outstanding (basic) (in shares)	175,942	174,991	175,672	174,582
Impact of common stock equivalents (in shares)	1,186	1,225	1,176	1,194
Weighted average shares outstanding (diluted) (in shares)	177,128	176,216	176,848	175,776

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income Changes in Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Equity [Abstract]
Unrealized gain on securities, before tax amount	$ (15,865)	$ 5,109	$ (59,250)	$ 27,482
Unrealized gain on securities, tax effect	3,334	(1,789)	12,444	(9,621)
Unrealized gain on securities, net of tax amount	(12,531)	3,320	(46,806)	17,861
Reclassification adjustment for securities gains included in net income, before tax amount	(14)	(4,597)	(37)	(7,139)
Reclassification adjustment for securities gains included in net income, tax effect	3	1,609	7	2,500
Reclassification adjustment for securities gains included in net income, net of tax amount	(11)	(2,988)	(30)	(4,639)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Investment Transferred from Available-for-sale to Held-to-maturity, before Tax	1,000		1,000
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Investment Transferred from Available-for-sale to Held-to-maturity, Tax	(209)		(209)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Investment Transferred from Available-for-sale to Held-to-maturity, after Tax	791	0	791	0
Non-credit related unrealized gains on other-than-temporarily impaired debt securities, before tax amount			294
Non-credit related unrealized gains on other-than-temporarily impaired debt securities, tax effect			(62)
Non-credit related unrealized gains on other-than-temporarily impaired debt securities, net of tax amount	0	0	(232)	0
Amortization of net unrecognized pension and postretirement items, before tax amount	466	523	1,580	1,575
Amortization of net unrecognized pension and postretirement items, tax effect	(97)	(183)	(332)	(551)
Amortization of net unrecognized pension and postretirement items, net of tax amount	369	340	1,248	1,024
Total Other Comprehensive Income, Before Tax Amount	(14,413)	1,035	(56,413)	21,918
Total Other Comprehensive Income, Tax Effect	3,031	(363)	11,848	(7,672)
Other Comprehensive (Loss) Income	$ (11,382)	$ 672	$ (44,565)	$ 14,246

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Income Components of Other Comprehensive Income (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance				$ 2,229,857	$ 2,121,115
Amortization of net unrealized losses on available for sale securities transferred to held to maturity		$ 791	$ 0	791	0
Reclassification of stranded tax effects	[1]			0
Ending Balance		2,283,014	2,225,786	2,283,014	2,225,786
Unrealized Gains (Losses) on Investment Securities Not Other-Than-Temporarily Impaired
Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance		(56,690)	(10,157)	(18,509)	(23,047)
Other comprehensive loss before reclassifications		(12,531)	3,320	(46,806)	17,861
Amounts reclassified from accumulated other comprehensive income (loss)		(11)	(2,988)	(30)	(4,639)
Amortization of net unrealized losses on available for sale securities transferred to held to maturity		791		791
Reclassification of stranded tax effects				(3,887)
Ending Balance		(68,441)	(9,825)	(68,441)	(9,825)
Unrealized Non-Credit Gains (Losses) on Other-Than-Temporarily Impaired Debt Securities
Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance		690	273	458	273
Other comprehensive loss before reclassifications		0	0	232	0
Amounts reclassified from accumulated other comprehensive income (loss)		0	0	0	0
Amortization of net unrealized losses on available for sale securities transferred to held to maturity		0		0
Reclassification of stranded tax effects				0
Ending Balance		690	273	690	273
Unrecognized Pension and Postretirement Plan Income (Costs)
Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance		(17,258)	(14,991)	(14,923)	(15,675)
Other comprehensive loss before reclassifications		0	0	0	0
Amounts reclassified from accumulated other comprehensive income (loss)		369	340	1,248	1,024
Amortization of net unrealized losses on available for sale securities transferred to held to maturity		0		0
Reclassification of stranded tax effects				(3,214)
Ending Balance		(16,889)	(14,651)	(16,889)	(14,651)
Total
Accumulated Other Comprehensive Income [Roll Forward]
Beginning Balance		(73,258)	(24,875)	(32,974)	(38,449)
Other comprehensive loss before reclassifications		(12,531)	3,320	(46,574)	17,861
Amounts reclassified from accumulated other comprehensive income (loss)		358	(2,648)	1,218	(3,615)
Amortization of net unrealized losses on available for sale securities transferred to held to maturity		791		791
Reclassification of stranded tax effects	[1]			(7,101)
Ending Balance		$ (84,640)	$ (24,203)	$ (84,640)	$ (24,203)
[1]	Result of adoption of ASU 2018-02, See Note 1 to Consolidated Financial Statements for further details.

Investment Securities Schedule

Investment Securities Schedule of Amortized Cost and Fair Values of Investment Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Schedule of Investments [Line Items]
Amortized Cost	$ 2,071,734
Gross Unrealized Gains	4,205
Gross Unrealized Losses	(67,123)
Estimated Fair Value	2,008,816
Amortized Cost, Held to Maturity	626,597	$ 0
Gross Unrealized Gains, Held to Maturity	2
Gross Unrealized Losses, Held to Maturity	(3,747)
Securities held to maturity	622,852
Amortized Cost		2,575,719
Gross Unrealized Gains		13,062
Gross Unrealized Losses		(40,825)
Estimated Fair Value		2,547,956
Pooled Trust Preferred Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	0	0
Estimated Fair Value	875	707
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Credit Losses on Debt Securities Held	11,500		$ 11,500
U.S. Government-Sponsored Agency Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	31,527
Gross Unrealized Gains	1
Gross Unrealized Losses	(437)
Estimated Fair Value	31,091
Amortized Cost		5,962
Gross Unrealized Gains		2
Gross Unrealized Losses		(26)
Estimated Fair Value		5,938
US States and Political Subdivisions Debt Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	269,582
Gross Unrealized Gains	1,281
Gross Unrealized Losses	(9,723)
Estimated Fair Value	261,140
Amortized Cost, Held to Maturity	156,267
Gross Unrealized Gains, Held to Maturity	0
Gross Unrealized Losses, Held to Maturity	(2,006)
Securities held to maturity	154,261
Amortized Cost		405,860
Gross Unrealized Gains		5,638
Gross Unrealized Losses		(2,549)
Estimated Fair Value		408,949
Corporate Debt Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	93,482	96,353
Gross Unrealized Gains	950
Gross Unrealized Losses	(2,142)
Estimated Fair Value	92,290	97,309
Amortized Cost		96,353
Gross Unrealized Gains		2,832
Gross Unrealized Losses		(1,876)
Estimated Fair Value		97,309
Collateralized Mortgage Obligations [Member]
Schedule of Investments [Line Items]
Amortized Cost	820,150
Gross Unrealized Gains	100
Gross Unrealized Losses	(23,016)
Estimated Fair Value	797,234
Amortized Cost		611,927
Gross Unrealized Gains		491
Gross Unrealized Losses		(9,795)
Estimated Fair Value		602,623
Mortgage-Backed Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	497,614
Gross Unrealized Gains	1,873
Gross Unrealized Losses	(21,310)
Estimated Fair Value	478,177
Amortized Cost, Held to Maturity	470,330
Gross Unrealized Gains, Held to Maturity	2
Gross Unrealized Losses, Held to Maturity	(1,741)
Securities held to maturity	468,591
Amortized Cost		1,132,080
Gross Unrealized Gains		3,957
Gross Unrealized Losses		(15,241)
Estimated Fair Value		1,120,796
Commercial Mortgage Backed Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	251,969
Gross Unrealized Gains	0
Gross Unrealized Losses	(6,218)
Estimated Fair Value	245,751
Amortized Cost		215,351
Gross Unrealized Gains		0
Gross Unrealized Losses		(2,596)
Estimated Fair Value		212,755
Auction Rate Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost	107,410
Gross Unrealized Gains	0
Gross Unrealized Losses	(4,277)
Estimated Fair Value	$ 103,133
Amortized Cost		107,410
Gross Unrealized Gains		0
Gross Unrealized Losses		(8,742)
Estimated Fair Value		98,668
Debt Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost		2,574,943
Gross Unrealized Gains		12,920
Gross Unrealized Losses		(40,825)
Estimated Fair Value		2,547,038
Equity Securities [Member]
Schedule of Investments [Line Items]
Amortized Cost		776
Gross Unrealized Gains		142
Gross Unrealized Losses		0
Estimated Fair Value		$ 918

Investment Securities Schedul_2

Investment Securities Schedule of Amortized Cost and Fair Values of Debt Securities by Contractual Maturities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Amortized Cost
Due in one year or less	$ 5,946
Due from one year to five years	52,613
Due from five years to ten years	105,838
Due after ten years	337,604
Amortized cost, before securities without debt maturities	502,001
Amortized Cost	2,071,734
Estimated Fair Value
Due in one year or less	5,949
Due from one year to five years	52,541
Due from five years to ten years	104,579
Due after ten years	324,585
Available for sale securities, debt maturities, before securities without single maturities	487,654
Estimated Fair Value	2,008,816
Amortized Cost
Due in one year or less	0
Due from one year to five years	0
Due from five years to ten years	0
Due after ten years	156,267
Debt securities, held-to-maturity, maturity, allocated and single maturity date, amortized cost, total	156,267
Amortized Cost, Held to Maturity	626,597	$ 0
Estimated Fair Value
Due in one year or less	0
Due from one year to five years	0
Due from five years to ten years	0
Due after ten years	154,261
Debt securities, held-to-maturity, maturity, Allocated and single maturity date, fair value	154,261
Estimated Fair Value, Held to Maturity	622,852
Collateralized Mortgage Obligations [Member]
Amortized Cost
Available-for-sale securities, amortized cost without single maturity date	820,150
Amortized Cost	820,150
Estimated Fair Value
Available-for-sale securities, debt maturities, without single maturity date, fair value	797,234
Estimated Fair Value	797,234
Amortized Cost
Debt securities, held-to-maturity, maturity, without single maturity date, amortized cost	0
Estimated Fair Value
Debt securities, held-to-maturity, maturity, without single maturity date, fair value	0
Commercial Mortgage Backed Securities [Member]
Amortized Cost
Available-for-sale securities, amortized cost without single maturity date	251,969
Amortized Cost	251,969
Estimated Fair Value
Available-for-sale securities, debt maturities, without single maturity date, fair value	245,751
Estimated Fair Value	245,751
Amortized Cost
Debt securities, held-to-maturity, maturity, without single maturity date, amortized cost	0
Estimated Fair Value
Debt securities, held-to-maturity, maturity, without single maturity date, fair value	0
Mortgage-Backed Securities [Member]
Amortized Cost
Available-for-sale securities, amortized cost without single maturity date	497,614
Amortized Cost	497,614
Estimated Fair Value
Available-for-sale securities, debt maturities, without single maturity date, fair value	478,177
Estimated Fair Value	478,177
Amortized Cost
Debt securities, held-to-maturity, maturity, without single maturity date, amortized cost	470,330
Amortized Cost, Held to Maturity	470,330
Estimated Fair Value
Debt securities, held-to-maturity, maturity, without single maturity date, fair value	468,591
Estimated Fair Value, Held to Maturity	$ 468,591

Investment Securities Summary o

Investment Securities Summary of Gains and Losses from Equity and Debt Securities, and Losses from Other-than-Temporary Impairment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Gain (Loss) on Securities [Line Items]
Equity securities, Gross Realized Gains	$ 0		$ 9
Equity securities, Gross Realized Losses	0		0
Equity securities, Net Gains (Losses)	0		9
Debt securities, Gross Realized Gains	116		1,656
Debt securities, Gross Realized Losses	102		1,628
Debt securities, Net Gains (Losses)	14		28
Debt and Equity securities, Gross Realized Gains	116		1,665
Debt and Equity securities, Gross Realized Losses	102		1,628
Debt and Equity securities, Net Gains (Losses)	$ 14		$ 37
Gross Realized Gains		$ 4,829		$ 7,385
Gross Realized Losses		(232)		(246)
Net Gains (Losses)		4,597		7,139
Equity Securities [Member]
Gain (Loss) on Securities [Line Items]
Gross Realized Gains		4,817		7,167
Gross Realized Losses		0		0
Net Gains (Losses)		4,817		7,167
Debt Securities [Member]
Gain (Loss) on Securities [Line Items]
Gross Realized Gains		12		218
Gross Realized Losses		(232)		(246)
Net Gains (Losses)		$ (220)		$ (28)

Investment Securities Gross Unr

Investment Securities Gross Unrealized Losses and Fair Values of Investments by Category and Length of Time in a Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	$ 1,090,407
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(24,552)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	774,558
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	(42,571)
Debt Securities, Available-for-sale, Unrealized Loss Position	1,864,965
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(67,123)
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	608,805
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(3,747)
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	0
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0
Debt Securities, Held-to-maturity, Unrealized Loss Position, Fair Value	608,805
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss	(3,747)
U.S. Government-Sponsored Agency Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	30,992
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(437)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	0
Debt Securities, Available-for-sale, Unrealized Loss Position	30,992
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(437)
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		$ 5,830
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		(26)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		5,830
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		(26)
State and Municipal Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	112,366
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(3,550)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	73,856
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	(6,173)
Debt Securities, Available-for-sale, Unrealized Loss Position	186,222
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(9,723)
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		11,650
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		(50)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		118,297
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		(2,499)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		129,947
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		(2,549)
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	154,261
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(2,006)
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	0
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0
Debt Securities, Held-to-maturity, Unrealized Loss Position, Fair Value	154,261
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss	(2,006)
Corporate Debt Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	56,159
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(694)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	22,700
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	(1,448)
Debt Securities, Available-for-sale, Unrealized Loss Position	78,859
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(2,142)
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		4,544
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		(48)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		32,163
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		(1,828)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		36,707
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		(1,876)
Collateralized Mortgage Obligations [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	620,047
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(12,833)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	168,560
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	(10,183)
Debt Securities, Available-for-sale, Unrealized Loss Position	788,607
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(23,016)
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		303,932
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		(2,408)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		187,690
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		(7,387)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		491,622
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		(9,795)
Residential Mortgage Backed Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	105,850
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(3,447)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	329,007
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	(17,863)
Debt Securities, Available-for-sale, Unrealized Loss Position	434,857
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(21,310)
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		511,378
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		(4,348)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		500,375
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		(10,893)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		1,011,753
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		(15,241)
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value	454,544
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(1,741)
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value	0
Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0
Debt Securities, Held-to-maturity, Unrealized Loss Position, Fair Value	454,544
Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss	(1,741)
Commercial Mortgage Backed Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	164,993
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	(3,591)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	77,302
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	(2,627)
Debt Securities, Available-for-sale, Unrealized Loss Position	242,295
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	(6,218)
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		190,985
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		(2,118)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		21,770
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		(478)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		212,755
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		(2,596)
Auction Rate Securities [Member]
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	103,133
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer	(4,277)
Debt Securities, Available-for-sale, Unrealized Loss Position	103,133
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ (4,277)
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		98,668
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		(8,742)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		98,668
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		(8,742)
Debt Securities [Member]
Schedule of Investments [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		1,028,319
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		(8,998)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		958,963
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		(31,827)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		1,987,282
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss		$ (40,825)

Investment Securities Summary_2

Investment Securities Summary of Amortized Cost and Fair Values of Corporate Debt Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 2,071,734
Estimated Fair Value	2,008,816
Corporate Debt Securities Issued by Financial Institutions [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	89,526	$ 92,379
Estimated Fair Value	88,334	93,335
Single-issuer Trust Preferred Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	20,860	31,335
Estimated Fair Value	19,596	30,703
Subordinated Debt [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	56,641	49,013
Estimated Fair Value	55,774	49,533
Senior Debt Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	12,025	12,031
Estimated Fair Value	12,089	12,392
Pooled Trust Preferred Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	0	0
Estimated Fair Value	875	707
Other Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	3,956	3,974
Estimated Fair Value	3,956	3,974
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	93,482	96,353
Estimated Fair Value	$ 92,290	$ 97,309

Investment Securities Narrative

Investment Securities Narrative (Details) $ in Thousands	Aug. 01, 2018USD ($)	Sep. 30, 2018USD ($)security	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)
Schedule of Investments [Line Items]
Debt securities held-to-maturity, fair value	$ 641,700
Available-for-sale securities, transfers to held-to-maturity, Amortized Cost	665,500
Amortized cost		$ 2,071,734
Available-for-sale Securities, Fair Value Disclosure		2,008,816
Pooled Trust Preferred Securities [Member]
Schedule of Investments [Line Items]
Other than Temporary Impairment, Credit Losses Recognized in Earnings, Credit Losses on Debt Securities Held		11,500		$ 11,500
Amortized cost		0	$ 0
Available-for-sale Securities, Fair Value Disclosure		875	707
Residential Mortgage Backed Securities [Member]
Schedule of Investments [Line Items]
Debt securities held-to-maturity, fair value	485,300
Available-for-sale securities, transfers to held-to-maturity, Amortized Cost	505,500
Amortized cost		497,614
Available-for-sale Securities, Fair Value Disclosure		478,177
US States and Political Subdivisions Debt Securities [Member]
Schedule of Investments [Line Items]
Debt securities held-to-maturity, fair value	156,400
Available-for-sale securities, transfers to held-to-maturity, Amortized Cost	$ 160,000
Amortized cost		269,582
Available-for-sale Securities, Fair Value Disclosure		261,140
Single-issuer Trust Preferred Securities [Member]
Schedule of Investments [Line Items]
Amortized cost		20,860	31,335
Available-for-sale Securities, Fair Value Disclosure		19,596	30,703
Unrealized loss on debt securities		$ 1,264
Number of Trust Preferred Securities | security		11
Single-issuer Trust Preferred Securities [Member] | External Credit Rating, BBB [Member]
Schedule of Investments [Line Items]
Amortized cost		$ 2,800
Available-for-sale Securities, Fair Value Disclosure		$ 2,500
Single-issuer Trust Preferred Securities [Member] | Not Rated By An External Agency [Member]
Schedule of Investments [Line Items]
Number of Trust Preferred Securities | security		1
Single-issuer Trust Preferred Securities [Member] | External Credit Rating, Rated Below Investment Grade [Member]
Schedule of Investments [Line Items]
Amortized cost		$ 2,000
Available-for-sale Securities, Fair Value Disclosure		$ 1,900
Number of Trust Preferred Securities | security		2
Collateral Pledged [Member]
Schedule of Investments [Line Items]
Securities pledged as collateral		$ 1,600,000	$ 1,800,000

Loans and Allowance for Credi_3

Loans and Allowance for Credit Losses Summary Of Gross Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	$ 15,954,326	$ 15,795,918
Unearned income	(29,233)	(27,671)
Loans, net of unearned income	15,925,093	15,768,247	$ 15,486,899
Real-estate - commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	6,337,984	6,364,804
Loans, net of unearned income	6,337,984	6,364,804	6,275,140
Commercial - industrial, financial and agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	4,288,823	4,300,297
Loans, net of unearned income	4,288,823	4,300,297	4,223,075
Real-estate - home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	1,469,152	1,559,719
Loans, net of unearned income	1,469,152	1,559,719	1,567,473
Real estate - residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	2,173,548	1,954,711
Loans, net of unearned income	2,173,548	1,954,711	1,887,907
Real-estate - construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	979,857	1,006,935
Loans, net of unearned income	979,857	1,006,935	973,108
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	390,708	313,783
Loans, net of unearned income	390,708	313,783	$ 302,448
Leasing and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	312,207	291,556
Overdrafts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross of unearned income	$ 2,047	$ 4,113

Loans and Allowance for Credi_4

Loans and Allowance for Credit Losses Allowance for Credit Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Receivables [Abstract]
Allowance for loan losses	$ 157,810	$ 156,050	$ 169,910	$ 172,245	$ 172,342	$ 168,679
Reserve for unfunded lending commitments	10,016		6,174
Allowance for credit losses	$ 167,826	$ 169,247	$ 176,084	$ 174,749	$ 174,998	$ 171,325

Loans and Allowance for Credi_5

Loans and Allowance for Credit Losses Activity in the Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	$ 169,247	$ 174,998	$ 176,084	$ 171,325
Loans charged off	(6,883)	(7,795)	(55,440)	(25,917)
Recoveries of loans previously charged off	3,842	2,471	8,475	12,766
Net loans charged off	(3,041)	(5,324)	(46,965)	(13,151)
Provision for credit losses	1,620	5,075	38,707	16,575
Balance at end of period	$ 167,826	$ 174,749	$ 167,826	$ 174,749

Loans and Allowance for Credi_6

Loans and Allowance for Credit Losses Allowance for Loan Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	$ 156,050	$ 172,342	$ 169,910	$ 168,679
Loans charged off	(6,883)	(7,795)	(55,440)	(25,917)
Recoveries of loans previously charged off	3,842	2,471	8,475	12,766
Net loans charged off	(3,041)	(5,324)	(46,965)	(13,151)
Provision for loan losses	4,801	5,227	34,865	16,717
Ending Balance	157,810	172,245	157,810	172,245
Provision for loan losses gross	3,200	152	3,800	142
Provision for credit losses	1,620	5,075	38,707	16,575
Real-estate - commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	56,583	57,372	58,793	46,842
Loans charged off	(650)	(483)	(1,283)	(1,949)
Recoveries of loans previously charged off	928	106	1,528	1,490
Net loans charged off	278	(377)	245	(459)
Provision for loan losses	(2,750)	(2,008)	(4,927)	8,604
Ending Balance	54,111	54,987	54,111	54,987
Commercial - industrial, financial and agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	59,045	67,642	66,280	54,353
Loans charged off	(3,541)	(2,714)	(46,178)	(13,594)
Recoveries of loans previously charged off	731	665	2,347	6,830
Net loans charged off	(2,810)	(2,049)	(43,831)	(6,764)
Provision for loan losses	(301)	5,392	33,485	23,396
Ending Balance	55,934	70,985	55,934	70,985
Real-estate - home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	16,247	17,456	18,127	26,801
Loans charged off	(743)	(547)	(1,967)	(1,837)
Recoveries of loans previously charged off	217	252	694	604
Net loans charged off	(526)	(295)	(1,273)	(1,233)
Provision for loan losses	2,890	1,297	1,757	(7,110)
Ending Balance	18,611	18,458	18,611	18,458
Real estate - residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	14,504	16,439	16,088	22,929
Loans charged off	(483)	(195)	(1,128)	(535)
Recoveries of loans previously charged off	317	219	520	600
Net loans charged off	(166)	24	(608)	65
Provision for loan losses	3,774	220	2,632	(6,311)
Ending Balance	18,112	16,683	18,112	16,683
Real-estate - construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	5,988	9,534	6,620	6,455
Loans charged off	(212)	(2,744)	(976)	(3,765)
Recoveries of loans previously charged off	664	629	1,414	1,550
Net loans charged off	452	(2,115)	438	(2,215)
Provision for loan losses	(961)	(283)	(1,579)	2,896
Ending Balance	5,479	7,136	5,479	7,136
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	1,699	1,794	2,045	3,574
Loans charged off	(672)	(373)	(2,276)	(1,659)
Recoveries of loans previously charged off	390	193	1,015	899
Net loans charged off	(282)	(180)	(1,261)	(760)
Provision for loan losses	1,429	383	2,062	(817)
Ending Balance	2,846	1,997	2,846	1,997
Leasing, other and overdrafts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	1,984	2,105	1,957	3,192
Loans charged off	(582)	(739)	(1,632)	(2,578)
Recoveries of loans previously charged off	595	407	957	793
Net loans charged off	13	(332)	(675)	(1,785)
Provision for loan losses	720	226	1,435	592
Ending Balance	2,717	1,999	2,717	1,999
Unallocated
Accounts, Notes, Loans and Financing Receivable [Line Items]
Beginning Balance	0	0	0	4,533
Loans charged off	0	0	0	0
Recoveries of loans previously charged off	0	0	0	0
Net loans charged off	0	0	0	0
Provision for loan losses	0	0	0	(4,533)
Ending Balance	$ 0	$ 0	$ 0	$ 0

Loans and Allowance for Credi_7

Loans and Allowance for Credit Losses Present Loans, Net of Unearned Income and Their Related Allowance for Loan Losses, by Portfolio Segment (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans collectively evaluated for impairment	$ 120,341			$ 126,544
Loans individually evaluated for impairment	37,469			45,701
Allowance for loan losses	157,810	$ 156,050	$ 169,910	172,245	$ 172,342	$ 168,679
Loans collectively evaluated for impairment	15,751,600			15,300,419
Loans individually evaluated for impairment	173,493			186,480
Loans, net of unearned income	15,925,093		15,768,247	15,486,899
Real-estate - commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans collectively evaluated for impairment	46,812			47,261
Loans individually evaluated for impairment	7,299			7,726
Allowance for loan losses	54,111	56,583	58,793	54,987	57,372	46,842
Loans collectively evaluated for impairment	6,290,143			6,228,935
Loans individually evaluated for impairment	47,841			46,205
Loans, net of unearned income	6,337,984		6,364,804	6,275,140
Commercial - industrial, financial and agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans collectively evaluated for impairment	47,028			55,486
Loans individually evaluated for impairment	8,906			15,499
Allowance for loan losses	55,934	59,045	66,280	70,985	67,642	54,353
Loans collectively evaluated for impairment	4,235,953			4,162,857
Loans individually evaluated for impairment	52,870			60,218
Loans, net of unearned income	4,288,823		4,300,297	4,223,075
Real-estate - home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans collectively evaluated for impairment	7,856			7,632
Loans individually evaluated for impairment	10,755			10,826
Allowance for loan losses	18,611	16,247	18,127	18,458	17,456	26,801
Loans collectively evaluated for impairment	1,444,898			1,543,551
Loans individually evaluated for impairment	24,254			23,922
Loans, net of unearned income	1,469,152		1,559,719	1,567,473
Real estate - residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans collectively evaluated for impairment	8,369			6,488
Loans individually evaluated for impairment	9,743			10,195
Allowance for loan losses	18,112	14,504	16,088	16,683	16,439	22,929
Loans collectively evaluated for impairment	2,133,718			1,845,329
Loans individually evaluated for impairment	39,830			42,578
Loans, net of unearned income	2,173,548		1,954,711	1,887,907
Real-estate - construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans collectively evaluated for impairment	4,718			5,702
Loans individually evaluated for impairment	761			1,434
Allowance for loan losses	5,479	5,988	6,620	7,136	9,534	6,455
Loans collectively evaluated for impairment	971,167			959,584
Loans individually evaluated for impairment	8,690			13,524
Loans, net of unearned income	979,857		1,006,935	973,108
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans collectively evaluated for impairment	2,841			1,976
Loans individually evaluated for impairment	5			21
Allowance for loan losses	2,846	1,699	2,045	1,997	1,794	3,574
Loans collectively evaluated for impairment	390,700			302,415
Loans individually evaluated for impairment	8			33
Loans, net of unearned income	390,708		313,783	302,448
Leasing, other and overdrafts
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans collectively evaluated for impairment	2,717			1,999
Loans individually evaluated for impairment	0			0
Allowance for loan losses	2,717	1,984	1,957	1,999	2,105	3,192
Loans collectively evaluated for impairment	285,021			257,748
Loans individually evaluated for impairment	0			0
Loans, net of unearned income	285,021		267,998	257,748
Unallocated
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for loan losses	$ 0	$ 0	$ 0	$ 0	$ 0	$ 4,533

Loans and Allowance for Credi_8

Loans and Allowance for Credit Losses Total Impaired Loans by Class Segments (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	$ 104,765	$ 88,716
Unpaid principal balance, with related allowance	128,499	141,739
Unpaid Principal Balance	233,264	230,455
Recorded investment, with no related allowance	68,863	75,111
Recorded investment, with related allowance	104,630	116,018
Recorded Investment	173,493	191,129
Related Allowance	37,469	41,521
Real-estate - commercial mortgage
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	27,298	26,728
Unpaid principal balance, with related allowance	28,584	33,710
Recorded investment, with no related allowance	25,665	22,886
Recorded investment, with related allowance	22,176	25,895
Related Allowance	7,299	8,112
Commercial
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	64,150	44,936
Unpaid principal balance, with related allowance	24,530	29,816
Recorded investment, with no related allowance	33,552	39,550
Recorded investment, with related allowance	19,318	24,175
Related Allowance	8,906	11,406
Real estate - residential mortgage
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	3,171	4,575
Unpaid principal balance, with related allowance	41,772	42,597
Recorded investment, with no related allowance	3,170	4,575
Recorded investment, with related allowance	36,660	37,132
Related Allowance	9,743	9,895
Construction
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with no related allowance	10,146	12,477
Unpaid principal balance, with related allowance	5,874	7,308
Recorded investment, with no related allowance	6,476	8,100
Recorded investment, with related allowance	2,214	4,097
Related Allowance	761	967
Real-estate - home equity
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	27,731	28,282
Recorded investment, with related allowance	24,254	24,693
Related Allowance	10,755	11,124
Consumer
Impaired Financing Receivables [Line Items]
Unpaid principal balance, with related allowance	8	26
Recorded investment, with related allowance	8	26
Related Allowance	$ 5	$ 17

Loans and Allowance for Credi_9

Loans and Allowance for Credit Losses Average Impaired Loans by Class Segment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	$ 66,235	$ 68,400	$ 72,080	$ 63,767
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	180	150	553	431
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	110,516	118,513	112,725	119,225
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	565	499	1,661	1,409
Impaired Financing Receivable, Average Recorded Investment	176,751	186,913	184,805	182,992
Impaired Financing Receivable, Interest Income, Accrual Method	745	649	2,214	1,840
Real-estate - commercial mortgage
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	26,051	21,698	25,702	22,770
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	94	72	274	213
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	23,734	25,910	24,727	27,518
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	85	86	260	259
Commercial
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	30,157	33,044	35,098	29,309
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	66	46	208	128
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	23,687	25,152	23,934	24,097
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	51	34	149	97
Real-estate - home equity
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	24,628	22,837	24,690	20,957
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	202	150	581	362
Real estate - residential mortgage
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	3,182	4,616	3,872	4,645
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	20	27	71	79
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	36,396	38,329	36,578	39,584
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	227	225	671	680
Construction
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment	6,845	9,042	7,408	7,043
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method	0	5	0	11
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	2,061	6,251	2,778	6,677
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	0	4	0	11
Consumer
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	10	34	18	36
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	0	0	0	0
Leasing, other and overdrafts
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment	0	0	0	356
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method	$ 0	$ 0	$ 0	$ 0

Loans and Allowance for Cred_10

Loans and Allowance for Credit Losses Credit Quality Indicators (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	$ 15,954,326	$ 15,795,918
Real-estate - commercial mortgage
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	6,337,984	6,364,804
Real-estate - commercial mortgage | Pass
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	6,032,828	6,066,396
Real-estate - commercial mortgage | Special Mention
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	170,362	147,604
Real-estate - commercial mortgage | December 31, 2017
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	134,794	150,804
Commercial
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	4,128,197	4,132,440
Commercial | Pass
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	3,839,283	3,831,485
Commercial | Special Mention
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	150,310	121,842
Commercial | December 31, 2017
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	138,604	179,113
Commercial - unsecured
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	160,626	167,857
Commercial - unsecured | Pass
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	152,796	159,620
Commercial - unsecured | Special Mention
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	3,898	5,478
Commercial - unsecured | December 31, 2017
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	3,932	2,759
Commercial - industrial, financial and agricultural
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	4,288,823	4,300,297
Commercial - industrial, financial and agricultural | Pass
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	3,992,079	3,991,105
Commercial - industrial, financial and agricultural | Special Mention
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	154,208	127,320
Commercial - industrial, financial and agricultural | December 31, 2017
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	142,536	181,872
Construction
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	136,305	163,102
Construction | Pass
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	120,249	143,759
Construction | Special Mention
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	7,677	5,259
Construction | December 31, 2017
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	8,379	14,084
Construction - commercial
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	760,645	765,816
Construction - commercial | Pass
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	756,477	761,218
Construction - commercial | Special Mention
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	552	846
Construction - commercial | December 31, 2017
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	3,616	3,752
Construction - Commercial and Commercial Residential
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	896,950	928,918
Construction - Commercial and Commercial Residential | Pass
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	876,726	904,977
Construction - Commercial and Commercial Residential | Special Mention
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	8,229	6,105
Construction - Commercial and Commercial Residential | December 31, 2017
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	11,995	17,836
Commercial Loans, Commerical Mortgages, Constructions Loans
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	$ 11,523,757	$ 11,594,019
Percentage of total loans rated	100.00%	100.00%
Commercial Loans, Commerical Mortgages, Constructions Loans | Pass
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	$ 10,901,633	$ 10,962,478
Percentage of total loans rated	94.60%	94.60%
Commercial Loans, Commerical Mortgages, Constructions Loans | Special Mention
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	$ 332,799	$ 281,029
Percentage of total loans rated	2.90%	2.40%
Commercial Loans, Commerical Mortgages, Constructions Loans | December 31, 2017
Internal risk ratings for loans by segment [Line Items]
Loans and Leases Receivable, Gross	$ 289,325	$ 350,512
Percentage of total loans rated	2.50%	3.00%

Loans and Allowance for Cred_11

Loans and Allowance for Credit Losses Summary of Delinquency and Non-Performing Status by Portfolio Segment (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2018USD ($)day	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	$ 15,925,093	$ 15,768,247	$ 15,486,899
Delinquent | Minimum
Financing Receivable, Impaired [Line Items]
Days past due | day	30
Delinquent | Maximum
Financing Receivable, Impaired [Line Items]
Days past due | day	89
Non-performing
Financing Receivable, Impaired [Line Items]
Days past due | day	90
Real-estate - home equity
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	$ 1,469,152	1,559,719	1,567,473
Real-estate - home equity | Performing
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	1,447,184	1,535,557
Real-estate - home equity | Delinquent
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	11,886	12,655
Real-estate - home equity | Non-performing
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	10,082	11,507
Real estate - residential mortgage
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	2,173,548	1,954,711	1,887,907
Real estate - residential mortgage | Performing
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	2,131,239	1,914,888
Real estate - residential mortgage | Delinquent
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	23,233	18,852
Real estate - residential mortgage | Non-performing
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	19,076	20,971
Construction - other
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	82,907	78,017
Construction - other | Performing
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	82,417	77,403
Construction - other | Delinquent
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	0	203
Construction - other | Non-performing
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	490	411
Consumer
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	58,630	55,213
Consumer | Performing
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	58,259	54,828
Consumer | Delinquent
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	311	315
Consumer | Non-performing
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	60	70
Consumer - indirect
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	332,078	258,570
Consumer - indirect | Performing
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	328,423	254,663
Consumer - indirect | Delinquent
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	3,435	3,681
Consumer - indirect | Non-performing
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	220	226
Consumer
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	390,708	313,783	302,448
Consumer | Performing
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	386,682	309,491
Consumer | Delinquent
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	3,746	3,996
Consumer | Non-performing
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	280	296
Leasing, other and overdrafts
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	285,021	267,998	$ 257,748
Leasing, other and overdrafts | Performing
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	282,812	267,111
Leasing, other and overdrafts | Delinquent
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	2,119	855
Leasing, other and overdrafts | Non-performing
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	90	32
Real Estate, Consumer, Leasing And Other Loans [Member] [Member]
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	4,401,336	4,174,228
Real Estate, Consumer, Leasing And Other Loans [Member] [Member] | Performing
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	4,330,334	4,104,450
Real Estate, Consumer, Leasing And Other Loans [Member] [Member] | Delinquent
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	40,984	36,561
Real Estate, Consumer, Leasing And Other Loans [Member] [Member] | Non-performing
Financing Receivable, Impaired [Line Items]
Loans, net of unearned income	$ 30,018	$ 33,217
Commercial Loans, Commerical Mortgages, Constructions Loans
Financing Receivable, Impaired [Line Items]
% of Total	100.00%	100.00%
Commercial Loans, Commerical Mortgages, Constructions Loans | Performing
Financing Receivable, Impaired [Line Items]
% of Total	98.40%	98.30%
Commercial Loans, Commerical Mortgages, Constructions Loans | Delinquent
Financing Receivable, Impaired [Line Items]
% of Total	0.90%	0.90%
Commercial Loans, Commerical Mortgages, Constructions Loans | Non-performing
Financing Receivable, Impaired [Line Items]
% of Total	0.70%	0.80%

Loans and Allowance for Cred_12

Loans and Allowance for Credit Losses Non-Performing Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Receivables [Abstract]
Non-accrual loans	$ 106,433	$ 124,749
Loans 90 days or more past due and still accruing	13,663	10,010
Total non-performing loans	120,096	134,759
Other real estate owned (OREO)	10,684	9,823
Total non-performing assets	$ 130,780	$ 144,582

Loans and Allowance for Cred_13

Loans and Allowance for Credit Losses Past Due Loan Status and Non-Accrual Loans by Portfolio Segment (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 183,907	$ 196,268
≥ 90 Days Past Due and Accruing	13,663	10,010
Non- accrual	106,433	124,749
Current	15,741,186	15,571,979
Loans, net of unearned income	15,925,093	15,768,247	$ 15,486,899
Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	51,329	40,709
Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	12,482	20,800
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	120,096	134,759
Real-estate - commercial mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	51,121	49,126
≥ 90 Days Past Due and Accruing	5,242	625
Non- accrual	32,151	34,822
Current	6,286,863	6,315,678
Loans, net of unearned income	6,337,984	6,364,804	6,275,140
Real-estate - commercial mortgage | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	12,129	9,456
Real-estate - commercial mortgage | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,599	4,223
Real-estate - commercial mortgage | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	37,393	35,447
Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	50,085	63,647
≥ 90 Days Past Due and Accruing	835	1,360
Non- accrual	41,327	52,255
Current	4,078,112	4,068,793
Loans, net of unearned income	4,128,197	4,132,440
Commercial | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	6,705	4,778
Commercial | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,218	5,254
Commercial | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	42,162	53,615
Commercial - unsecured
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,023	1,009
≥ 90 Days Past Due and Accruing	29	45
Non- accrual	1,200	649
Current	158,603	166,848
Loans, net of unearned income	160,626	167,857
Commercial - unsecured | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	357	305
Commercial - unsecured | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	437	10
Commercial - unsecured | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,229	694
Commercial - industrial, financial and agricultural
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	52,108	64,656
≥ 90 Days Past Due and Accruing	864	1,405
Non- accrual	42,527	52,904
Current	4,236,715	4,235,641
Loans, net of unearned income	4,288,823	4,300,297	4,223,075
Commercial - industrial, financial and agricultural | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	7,062	5,083
Commercial - industrial, financial and agricultural | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,655	5,264
Commercial - industrial, financial and agricultural | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	43,391	54,309
Real-estate - home equity
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	21,968	24,162
≥ 90 Days Past Due and Accruing	2,037	2,372
Non- accrual	8,045	9,135
Current	1,447,184	1,535,557
Loans, net of unearned income	1,469,152	1,559,719	1,567,473
Real-estate - home equity | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	9,383	9,640
Real-estate - home equity | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,503	3,015
Real-estate - home equity | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	10,082	11,507
Real estate - residential mortgage
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	42,309	39,823
≥ 90 Days Past Due and Accruing	4,056	5,280
Non- accrual	15,020	15,691
Current	2,131,239	1,914,888
Loans, net of unearned income	2,173,548	1,954,711	1,887,907
Real estate - residential mortgage | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	17,731	11,961
Real estate - residential mortgage | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	5,502	6,891
Real estate - residential mortgage | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	19,076	20,971
Construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	9,657	12,206
≥ 90 Days Past Due and Accruing	896	0
Non- accrual	8,379	11,767
Current	126,648	150,896
Loans, net of unearned income	136,305	163,102
Construction | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	157	0
Construction | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	225	439
Construction | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	9,275	11,767
Construction - commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	19	502
≥ 90 Days Past Due and Accruing	0	0
Non- accrual	19	19
Current	760,626	765,314
Loans, net of unearned income	760,645	765,816
Construction - commercial | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	483
Construction - commercial | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Construction - commercial | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	19	19
Construction - other
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	490	614
≥ 90 Days Past Due and Accruing	198	0
Non- accrual	292	411
Current	82,417	77,403
Loans, net of unearned income	82,907	78,017
Construction - other | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	203
Construction - other | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0	0
Construction - other | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	490	411
Real-estate - construction
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	10,166	13,322
≥ 90 Days Past Due and Accruing	1,094	0
Non- accrual	8,690	12,197
Current	969,691	993,613
Loans, net of unearned income	979,857	1,006,935	973,108
Real-estate - construction | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	157	686
Real-estate - construction | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	225	439
Real-estate - construction | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	9,784	12,197
Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	371	385
≥ 90 Days Past Due and Accruing	60	70
Non- accrual	0	0
Current	58,259	54,828
Loans, net of unearned income	58,630	55,213
Consumer | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	225	260
Consumer | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	86	55
Consumer | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	60	70
Consumer - indirect
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	3,655	3,907
≥ 90 Days Past Due and Accruing	220	226
Non- accrual	0	0
Current	328,423	254,663
Loans, net of unearned income	332,078	258,570
Consumer - indirect | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,903	3,055
Consumer - indirect | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	532	626
Consumer - indirect | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	220	226
Consumer
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	4,026	4,292
≥ 90 Days Past Due and Accruing	280	296
Non- accrual	0	0
Current	386,682	309,491
Loans, net of unearned income	390,708	313,783	302,448
Consumer | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	3,128	3,315
Consumer | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	618	681
Consumer | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	280	296
Leasing, other and overdrafts
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,209	887
≥ 90 Days Past Due and Accruing	90	32
Non- accrual	0	0
Current	282,812	267,111
Loans, net of unearned income	285,021	267,998	$ 257,748
Leasing, other and overdrafts | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,739	568
Leasing, other and overdrafts | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	380	287
Leasing, other and overdrafts | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 90	$ 32

Loans and Allowance for Cred_14

Loans and Allowance for Credit Losses Loans Modified Under Troubled Debt Restructurings (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Financing Receivable, Modifications [Line Items]
Total Accruing Troubled Debt Restructurings	$ 67,058	$ 66,379
Non-accrual TDRs (1)	23,238	29,051
Total TDRs	90,296	95,430
Residential Mortgage [Member]
Financing Receivable, Modifications [Line Items]
Total Accruing Troubled Debt Restructurings	24,810	26,016
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Total Accruing Troubled Debt Restructurings	15,690	13,959
Real-estate - home equity
Financing Receivable, Modifications [Line Items]
Total Accruing Troubled Debt Restructurings	16,208	15,558
Commercial
Financing Receivable, Modifications [Line Items]
Total Accruing Troubled Debt Restructurings	10,342	10,820
Consumer
Financing Receivable, Modifications [Line Items]
Total Accruing Troubled Debt Restructurings	$ 8	$ 26

Loans and Allowance for Cred_15

Loans and Allowance for Credit Losses Troubled Debt Restructuring Modification (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018USD ($)loans	Sep. 30, 2017USD ($)loans	Sep. 30, 2018USD ($)loans	Sep. 30, 2017USD ($)loans
Financing Receivable, Modifications [Line Items]
Number of Loans | loans	30	27	90	97
Post-Modification Recorded Investment | $	$ 2,512	$ 3,468	$ 15,049	$ 16,628
Extend maturity with rate concession | Real estate - residential mortgage
Financing Receivable, Modifications [Line Items]
Number of Loans | loans	3	2	3	2
Post-Modification Recorded Investment | $	$ 330	$ 468	$ 330	$ 468
Extend maturity without rate concession | Commercial
Financing Receivable, Modifications [Line Items]
Number of Loans | loans	2	1	7	9
Post-Modification Recorded Investment | $	$ 913	$ 160	$ 2,064	$ 5,853
Extend maturity without rate concession | Commercial - unsecured
Financing Receivable, Modifications [Line Items]
Number of Loans | loans	0	0	0	1
Post-Modification Recorded Investment | $	$ 0	$ 0	$ 0	$ 33
Extend maturity without rate concession | Real-estate - commercial mortgage
Financing Receivable, Modifications [Line Items]
Number of Loans | loans	0	2	6	6
Post-Modification Recorded Investment | $	$ 0	$ 1,247	$ 8,261	$ 2,228
Extend maturity without rate concession | Real-estate - home equity
Financing Receivable, Modifications [Line Items]
Number of Loans | loans	23	14	63	47
Post-Modification Recorded Investment | $	$ 985	$ 1,315	$ 3,607	$ 3,874
Extend maturity without rate concession | Real estate - residential mortgage
Financing Receivable, Modifications [Line Items]
Number of Loans | loans	1	2	2	4
Post-Modification Recorded Investment | $	$ 267	$ 151	$ 344	$ 488
Extend maturity without rate concession | Construction
Financing Receivable, Modifications [Line Items]
Number of Loans | loans	0	0	0	1
Post-Modification Recorded Investment | $	$ 0	$ 0	$ 0	$ 1,204
Bankruptcy | Commercial
Financing Receivable, Modifications [Line Items]
Number of Loans | loans	0	0	0	1
Post-Modification Recorded Investment | $	$ 0	$ 0	$ 0	$ 490
Bankruptcy | Real-estate - commercial mortgage
Financing Receivable, Modifications [Line Items]
Number of Loans | loans	0	0	0	1
Post-Modification Recorded Investment | $	$ 0	$ 0	$ 0	$ 12
Bankruptcy | Real-estate - home equity
Financing Receivable, Modifications [Line Items]
Number of Loans | loans	1	6	8	23
Post-Modification Recorded Investment | $	$ 17	$ 127	$ 438	$ 1,643
Bankruptcy | Real estate - residential mortgage
Financing Receivable, Modifications [Line Items]
Number of Loans | loans	0	0	1	2
Post-Modification Recorded Investment | $	$ 0	$ 0	$ 5	$ 335

Loans and Allowance for Cred_16

Loans and Allowance for Credit Losses TDRs by Class Segment (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018USD ($)loans	Sep. 30, 2017USD ($)loans	Sep. 30, 2018USD ($)loans	Sep. 30, 2017USD ($)loans
Financing Receivable, Modifications [Line Items]
Post-Modification Recorded Investment	$ 2,512	$ 3,468	$ 15,049	$ 16,628
Number of Loans | loans	30	27	90	97
Number of Loans | loans			37	39
Recorded Investment			$ 7,809	$ 5,445
Real estate - residential mortgage
Financing Receivable, Modifications [Line Items]
Number of Loans | loans			6	5
Recorded Investment			$ 724	$ 1,321
Real-estate - commercial mortgage
Financing Receivable, Modifications [Line Items]
Number of Loans			2	3
Recorded Investment			$ 452	$ 653
Real-estate - home equity
Financing Receivable, Modifications [Line Items]
Number of Loans | loans			25	27
Recorded Investment			$ 1,591	$ 1,598
Commercial
Financing Receivable, Modifications [Line Items]
Number of Loans | loans			4	2
Recorded Investment			$ 5,042	$ 264
Construction - other
Financing Receivable, Modifications [Line Items]
Number of Loans | loans	0	2
Recorded Investment	$ 0	$ 1,609

Loans and Allowance for Cred_17

Loans and Allowance for Credit Losses Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for credit losses	$ 1,620	$ 5,075	$ 38,707	$ 16,575
Loans charged off	$ 6,883	$ 7,795	$ 55,440	$ 25,917
Impaired loans with principal balances approximately in percentage			93.00%		94.00%
Loan to value ratio in the Corporation's policy	70.00%		70.00%
Recorded investment, with no related allowance	$ 68,863		$ 68,863		$ 75,111
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Minimum balance of loans evaluated individually for impairment			1,000
Impaired loans balances, real estate as collateral	1,000		1,000
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Minimum balance of loans evaluated individually for impairment			1,000
Commercial Relationship
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for credit losses	36,800		36,800
Loans charged off	$ 33,900		$ 33,900

Mortgage Servicing Rights Summa

Mortgage Servicing Rights Summary of Changes in Mortgage Servicing Rights (Details) - Residential Mortgage [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Amortized Cost:
Balance at beginning of period	$ 37,894	$ 38,180	$ 37,663	$ 38,822
Originations of mortgage servicing rights	2,018	1,333	5,247	3,719
Amortization	(1,684)	(1,639)	(4,682)	(4,667)
Balance at end of period	38,228	37,874	38,228	37,874
Valuation allowance:
Balance at beginning of period	0	0	0	(1,291)
Balance at end of period	0	0	0	0
Net MSRs at end of period	$ 38,228	$ 37,874	$ 38,228	$ 37,874

Mortgage Servicing Rights - Nar

Mortgage Servicing Rights - Narrative (Details) - Residential Mortgage [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Servicing Asset at Amortized Cost [Line Items]
Valuation Allowance for Impairment of Recognized Servicing Assets, Additions (Deductions) for Expenses (Recoveries)	$ 0	$ 0	$ 0	$ 1,291
Valuation Allowance for Impairment of Recognized Servicing Assets, Balance	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 1,291

Stock-Based Compensation Compen

Stock-Based Compensation Compensation Expense and Related Tax Benefits (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Compensation expense	$ 1,823	$ 1,570	$ 6,007	$ 3,339
Tax benefit	(492)	(628)	(2,028)	(3,312)
Stock-based compensation expense, net of tax benefit	$ 1,331	$ 942	$ 3,979	$ 27

Stock-Based Compensation Narrat

Stock-Based Compensation Narrative (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement [Line Items]
Compensation expense	$ 1,823	$ 1,570	$ 6,007	$ 3,339
Stock-based compensation expense, net of tax benefit	$ 1,331	$ 942	$ 3,979	$ 27
Directors' Plan [Member]
Statement [Line Items]
Shares reserved for future grants under the stock option and compensation plan	329		329
Employee Equity Plan [Member]
Statement [Line Items]
Awards vesting period (in years)			3 years
Shares reserved for future grants under the stock option and compensation plan	10,600		10,600

Employee Benefit Plans Summary

Employee Benefit Plans Summary of Pension Plan and Postretirement Plan Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 763	$ 830	$ 2,290	$ 2,490
Expected return on plan assets	(512)	(451)	(1,536)	(1,353)
Net amortization and deferral	607	663	1,822	1,989
Net periodic benefit	858	1,042	2,576	3,126
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	13	17	42	51
Net accretion and deferral	(139)	(141)	(419)	(423)
Net periodic benefit	$ (126)	$ (124)	$ (377)	$ (372)

Derivative Financial Instrume_3

Derivative Financial Instruments Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Derivative [Line Items]
Assets	$ 20,364,810		$ 20,364,810		$ 20,036,905
Foreign currency open position	500		500
Mortgage Loans Held For Sale [Member]
Derivative [Line Items]
Gain (loss) in fair values of mortgage loans held for sale	$ (334)	$ (120)	$ (207)	$ 445
Fulton Bank Subsidiary [Member]
Derivative [Line Items]
Assets						$ 10,000,000

Derivative Financial Instrume_4

Derivative Financial Instruments Notional Amounts and Fair Values of Derivative Financial Instruments (Details) - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Derivative [Line Items]
Derivative asset, fair value	$ (66,020,000)	$ (43,630,000)
Derivative liability, fair value	(75,146,000)	(38,997,000)
Derivative asset (liability), net	(7,902,000)	5,611,000
Interest Rate Lock Commitments [Member]
Derivative [Line Items]
Derivative asset, notional amount	143,869,000	129,469,000
Derivative liability, notional amount	11,535,000	8,957,000
Derivative asset, fair value	(904,000)	(1,059,000)
Derivative liability, fair value	(77,000)	(59,000)
Derivative asset (liability), net	827,000	1,000,000
Forward Commitments [Member]
Derivative [Line Items]
Derivative asset, notional amount	122,856,000	3,856,000
Derivative liability, notional amount	0	100,808,000
Derivative asset, fair value	(480,000)	(34,000)
Derivative liability, fair value	0	(213,000)
Derivative asset (liability), net	480,000	(179,000)
Interest Rate Swap with Customer [Member]
Derivative [Line Items]
Derivative asset, notional amount	548,277,000	1,316,548,000
Derivative liability, notional amount	1,882,655,000	716,634,000
Derivative asset, fair value	(6,922,000)	(24,505,000)
Derivative liability, fair value	(71,175,000)	(18,978,000)
Derivative asset (liability), net	(64,253,000)	5,527,000
Interest Rate Swap With Counterparty [Member]
Derivative [Line Items]
Derivative asset, notional amount	1,882,655,000	716,634,000
Derivative liability, notional amount	548,277,000	1,316,548,000
Derivative asset, fair value	(58,773,000)	(18,941,000)
Derivative liability, fair value	(3,778,000)	(19,764,000)
Derivative asset (liability), net	54,995,000	(823,000)
Centrally Cleared Interest Rate Swap with Counterparty [Member]
Derivative [Line Items]
Derivative liability, fair value	0	0
Derivative Asset, Collateral, Obligation to Return Cash, Offset	9,300,000
Derivatives variation margin		4,600,000
Centrally Cleared Interest Rate Swap with Counterparty [Member] | Positive Fair Values [Member]
Derivative [Line Items]
Derivative asset, notional amount	416,100,000	24,400,000
Derivative asset, fair value	0	0
Centrally Cleared Interest Rate Swap with Counterparty [Member] | Negative Fair Values [Member]
Derivative [Line Items]
Derivative liability, notional amount	249,700,000	377,100,000
Derivative liability, fair value	0	0
Foreign Exchange Contracts With Customer [Member]
Derivative [Line Items]
Derivative asset, notional amount	8,797,000	4,852,000
Derivative liability, notional amount	9,176,000	5,914,000
Derivative asset, fair value	(193,000)	(276,000)
Derivative liability, fair value	(277,000)	(119,000)
Derivative asset (liability), net	(84,000)	157,000
Foreign Exchange Contracts With Correspondent Banks [Member]
Derivative [Line Items]
Derivative asset, notional amount	10,506,000	7,960,000
Derivative liability, notional amount	9,239,000	6,048,000
Derivative asset, fair value	(325,000)	(184,000)
Derivative liability, fair value	(192,000)	(255,000)
Derivative asset (liability), net	$ 133,000	$ (71,000)

Derivative Financial Instrume_5

Derivative Financial Instruments Fair Value Gains and Losses on Derivative Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Derivative [Line Items]
Net fair value (losses) gains on derivative financial instruments	$ (3,188)	$ 1,123	$ (13,513)	$ 4,768
Interest rate lock with customers [Member]
Derivative [Line Items]
Net fair value (losses) gains on derivative financial instruments	(533)	(59)	(173)	631
Forward Commitments [Member]
Derivative [Line Items]
Net fair value (losses) gains on derivative financial instruments	974	(48)	659	(2,270)
Interest Rate Swap with Customer [Member]
Derivative [Line Items]
Net fair value (losses) gains on derivative financial instruments	(14,763)	(47)	(69,780)	12,947
Interest Rate Swap with Counterparty [Member]
Derivative [Line Items]
Net fair value (losses) gains on derivative financial instruments	11,193	1,248	55,818	(6,582)
Foreign Exchange Contracts With Customer [Member]
Derivative [Line Items]
Net fair value (losses) gains on derivative financial instruments	(225)	140	(241)	(177)
Foreign Exchange Contracts With Correspondent Banks [Member]
Derivative [Line Items]
Net fair value (losses) gains on derivative financial instruments	166	(111)	204	219
Centrally Cleared Interest Rate Swap with Counterparty [Member]
Derivative [Line Items]
Net fair value (losses) gains on derivative financial instruments	$ 3,600	$ 1,200	$ 13,900	$ 6,300

Derivative Financial Instrume_6

Derivative Financial Instruments Summary of Mortgage Loans Held For Sale (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans Held-for-sale, Mortgages	$ 27,525		$ 27,525		$ 31,530
Mortgage Loans Held For Sale [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair Value, Option, Changes in Fair Value, Gain (Loss)	(334)	$ (120)	(207)	$ 445
Cost [Member] | Mortgage Loans Held For Sale [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans Held-for-sale, Mortgages	27,271		27,271		31,069
Fair value [Member] | Mortgage Loans Held For Sale [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans Held-for-sale, Mortgages	$ 27,525		$ 27,525		$ 31,530

Derivative Financial Instrume_7

Derivative Financial Instruments Offsetting Derivative Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Offsetting Assets [Line Items]
Derivative asset, fair value	$ 66,020	$ 43,630
Derivative, Collateral, Obligation to Return Securities	4,854	17,028
Derivative, Collateral, Obligation to Return Cash	(56,630)	0
Net Amount	4,536	26,602
Derivative liability, gross liability	75,146	38,997
Derivative liability, Collateral, Right to Reclaim Securities	(4,854)	(17,028)
Derivative liability, Collateral, Right to Reclaim Cash	(13,628)	(6,588)
Derivative liability, Net Amount	56,664	15,381
Interest Rate Swap [Member]
Offsetting Assets [Line Items]
Derivative asset, fair value	65,695	43,446
Derivative, Collateral, Obligation to Return Securities	4,662	16,844
Derivative, Collateral, Obligation to Return Cash	(56,630)	0
Net Amount	4,403	26,602
Derivative liability, gross liability	74,954	38,742
Derivative liability, Collateral, Right to Reclaim Securities	(4,662)	(16,844)
Derivative liability, Collateral, Right to Reclaim Cash	(13,628)	(6,588)
Derivative liability, Net Amount	56,664	15,310
Foreign Exchange Contract [Member]
Offsetting Assets [Line Items]
Derivative asset, fair value	325	184
Derivative, Collateral, Obligation to Return Securities	192	184
Derivative, Collateral, Obligation to Return Cash	0	0
Net Amount	133	0
Derivative liability, gross liability	192	255
Derivative liability, Collateral, Right to Reclaim Securities	(192)	(184)
Derivative liability, Collateral, Right to Reclaim Cash	0	0
Derivative liability, Net Amount	$ 0	$ 71

Commitments and Contingencies O

Commitments and Contingencies Outstanding Commitments to Extend Credit and Letters of Credit (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Commitments to Extend Credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Valuation allowances and reserves, balance	$ 6,562,515	$ 6,205,029
Standby Letters of Credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Valuation allowances and reserves, balance	325,386	326,973
Commercial Letters of Credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Valuation allowances and reserves, balance	$ 42,285	$ 41,801

Commitments and Contingencies -

Commitments and Contingencies - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Loss Contingencies [Line Items]
Outstanding repurchase request		$ 543
Residential Mortgage [Member]
Loss Contingencies [Line Items]
Valuation allowances and reserves, balance	$ 1,900	$ 2,100

Fair Value Measurements Assets

Fair Value Measurements Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	$ 2,008,816
Available-for-sale Securities, Fair Value Disclosure		$ 2,547,956
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	2,008,816
Mortgages Held-for-sale, Fair Value Disclosure	27,525	31,530
Available-for-sale Securities, Fair Value Disclosure		2,547,956
Investments held in Rabbi Trust	20,038	18,982
Other assets	67,609	45,008
Assets, Fair Value Disclosure	2,123,988	2,643,476
Other liabilities	95,540	58,371
Pooled Trust Preferred Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	875	707
Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		918
Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		918
U.S. Government-Sponsored Agency Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	31,091
Available-for-sale Securities, Fair Value Disclosure		5,938
U.S. Government-Sponsored Agency Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	31,091
Available-for-sale Securities, Fair Value Disclosure		5,938
US States and Political Subdivisions Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	261,140
Available-for-sale Securities, Fair Value Disclosure		408,949
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	261,140
Available-for-sale Securities, Fair Value Disclosure		408,949
Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	92,290	97,309
Available-for-sale Securities, Fair Value Disclosure		97,309
Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	92,290
Available-for-sale Securities, Fair Value Disclosure		97,309
Collateralized Mortgage Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	797,234
Available-for-sale Securities, Fair Value Disclosure		602,623
Collateralized Mortgage Obligations [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	797,234
Available-for-sale Securities, Fair Value Disclosure		602,623
Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	478,177
Available-for-sale Securities, Fair Value Disclosure		1,120,796
Mortgage-Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	478,177
Available-for-sale Securities, Fair Value Disclosure		1,120,796
Commercial Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	245,751
Available-for-sale Securities, Fair Value Disclosure		212,755
Commercial Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	245,751
Available-for-sale Securities, Fair Value Disclosure		212,755
Auction Rate Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	103,133
Available-for-sale Securities, Fair Value Disclosure		98,668
Auction Rate Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	103,133
Available-for-sale Securities, Fair Value Disclosure		98,668
Single-issuer Trust Preferred Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	19,596	30,703
Single-issuer Trust Preferred Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	19,600	30,700
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0
Mortgages Held-for-sale, Fair Value Disclosure	0	0
Available-for-sale Securities, Fair Value Disclosure		918
Investments held in Rabbi Trust	20,038	18,982
Other assets	530	469
Assets, Fair Value Disclosure	20,568	20,369
Other liabilities	20,509	19,357
Fair Value, Inputs, Level 1 [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		918
Fair Value, Inputs, Level 1 [Member] | U.S. Government-Sponsored Agency Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 1 [Member] | US States and Political Subdivisions Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 1 [Member] | Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 1 [Member] | Collateralized Mortgage Obligations [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 1 [Member] | Mortgage-Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 1 [Member] | Commercial Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 1 [Member] | Auction Rate Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	1,902,333
Mortgages Held-for-sale, Fair Value Disclosure	27,525	31,530
Available-for-sale Securities, Fair Value Disclosure		2,444,613
Investments held in Rabbi Trust	0	0
Other assets	67,079	44,539
Assets, Fair Value Disclosure	1,996,937	2,520,682
Other liabilities	75,031	39,014
Fair Value, Inputs, Level 2 [Member] | Other Corporate Debt [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	4,000	4,000
Fair Value, Inputs, Level 2 [Member] | Financial Institutions Subordinated Debt [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	67,900	61,900
Fair Value, Inputs, Level 2 [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 2 [Member] | U.S. Government-Sponsored Agency Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	31,091
Available-for-sale Securities, Fair Value Disclosure		5,938
Fair Value, Inputs, Level 2 [Member] | US States and Political Subdivisions Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	261,140
Available-for-sale Securities, Fair Value Disclosure		408,949
Fair Value, Inputs, Level 2 [Member] | Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	88,940
Available-for-sale Securities, Fair Value Disclosure		93,552
Fair Value, Inputs, Level 2 [Member] | Collateralized Mortgage Obligations [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	797,234
Available-for-sale Securities, Fair Value Disclosure		602,623
Fair Value, Inputs, Level 2 [Member] | Mortgage-Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	478,177
Available-for-sale Securities, Fair Value Disclosure		1,120,796
Fair Value, Inputs, Level 2 [Member] | Commercial Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	245,751
Available-for-sale Securities, Fair Value Disclosure		212,755
Fair Value, Inputs, Level 2 [Member] | Auction Rate Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 2 [Member] | Single-issuer Trust Preferred Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	17,000	27,700
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	106,483
Mortgages Held-for-sale, Fair Value Disclosure	0	0
Available-for-sale Securities, Fair Value Disclosure		102,425
Investments held in Rabbi Trust	0	0
Other assets	0	0
Assets, Fair Value Disclosure	106,483	102,425
Other liabilities	0	0
Fair Value, Inputs, Level 3 [Member] | Pooled Trust Preferred Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	875	707
Fair Value, Inputs, Level 3 [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 3 [Member] | U.S. Government-Sponsored Agency Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 3 [Member] | US States and Political Subdivisions Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 3 [Member] | Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	3,350
Available-for-sale Securities, Fair Value Disclosure		3,757
Fair Value, Inputs, Level 3 [Member] | Collateralized Mortgage Obligations [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 3 [Member] | Mortgage-Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 3 [Member] | Commercial Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	0
Available-for-sale Securities, Fair Value Disclosure		0
Fair Value, Inputs, Level 3 [Member] | Auction Rate Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	103,133
Available-for-sale Securities, Fair Value Disclosure		98,668
Fair Value, Inputs, Level 3 [Member] | Single-issuer Trust Preferred Securities [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated Fair Value	$ 2,500	$ 3,100

Fair Value Measurements Changes

Fair Value Measurements Changes in Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Level 3 Inputs (Details) - Fair Value, Measurements, Recurring [Member] - Fair Value, Inputs, Level 3 [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Pooled Trust Preferred Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$ 875	$ 422	$ 707	$ 422
Realized adjustment to fair value	0
Unrealized adjustment to fair value	0	0	168	0
Settlements - calls	0		0
(Premium amortization) discount accretion	0	0	0	0
Balance, end of period	875	422	875	422
Single-issuer Trust Preferred Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	3,200	2,775	3,050	2,450
Realized adjustment to fair value	71		71
Unrealized adjustment to fair value	153	(28)	297	291
Settlements - calls	950		950
(Premium amortization) discount accretion	1	3	7	9
Balance, end of period	2,475	2,750	2,475	2,750
Auction Rate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	103,122	97,923	98,668	97,256
Realized adjustment to fair value	0
Unrealized adjustment to fair value	11	233	4,465	705
Settlements - calls	0		0
(Premium amortization) discount accretion	0	0	0	195
Balance, end of period	$ 103,133	$ 98,156	$ 103,133	$ 98,156

Fair Value Measurements Asset_2

Fair Value Measurements Assets Measured at Fair Value on a Nonrecurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
OREO	$ 10,684	$ 9,823
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net loans	136,024	149,608
OREO	10,684	9,823
MSRs	38,228	37,663
Assets, Fair Value Disclosure	$ 184,936	$ 197,094

Fair Value Measurements Details

Fair Value Measurements Details of Book Value and Fair Value of Financial Instruments (Details) - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, FinancialStatement Captions[Line Items]
Securities held to maturity	$ 622,852,000
Estimated Fair Value	2,008,816,000
Available for sale investment securities		$ 2,547,956,000
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, FinancialStatement Captions[Line Items]
Cash and due from banks	90,361,000	108,291,000
Interest-bearing deposits with other banks	322,330,000	293,805,000
Federal Reserve Bank and Federal Home Loan Bank stock	65,926,000	60,761,000
Loans held for sale	27,525,000	31,530,000
Securities held to maturity	626,597,000
Estimated Fair Value	2,008,816,000
Available for sale investment securities		2,547,956,000
Net Loans	15,767,283,000	15,598,337,000
Accrued interest receivable	58,584,000	52,910,000
Other financial assets	242,140,000	215,464,000
Demand and savings deposits	13,384,227,000	13,042,147,000
Brokered deposits	164,601,000	90,473,000
Time deposits	2,700,186,000	2,664,912,000
Short-term borrowings	485,565,000	617,524,000
Accrued interest payable	11,151,000	9,317,000
Other financial liabilities	251,460,000	227,569,000
Federal Home Loan Bank advances and long-term debt	992,115,000	1,038,346,000
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, FinancialStatement Captions[Line Items]
Cash and due from banks	90,361,000	108,291,000
Interest-bearing deposits with other banks	322,330,000	293,805,000
Federal Reserve Bank and Federal Home Loan Bank stock	65,926,000	60,761,000
Loans held for sale	27,525,000	31,530,000
Securities held to maturity	622,852,000
Estimated Fair Value	2,008,816,000
Available for sale investment securities		2,547,956,000
Net Loans	15,124,455,000	15,380,974,000
Accrued interest receivable	58,584,000	52,910,000
Other financial assets	242,139,000	215,464,000
Demand and savings deposits	13,384,227,000	13,042,147,000
Brokered deposits	164,601,000	90,473,000
Time deposits	2,684,783,000	2,664,912,000
Short-term borrowings	485,565,000	617,524,000
Accrued interest payable	11,151,000	9,317,000
Other financial liabilities	251,460,000	227,569,000
Federal Home Loan Bank advances and long-term debt	960,168,000	1,038,346,000
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, FinancialStatement Captions[Line Items]
Cash and due from banks	90,361,000	108,291,000
Interest-bearing deposits with other banks	322,330,000	293,805,000
Federal Reserve Bank and Federal Home Loan Bank stock	0	0
Loans held for sale	0	0
Securities held to maturity	622,852,000
Estimated Fair Value	0
Available for sale investment securities		918,000
Net Loans	0	0
Accrued interest receivable	58,584,000	52,910,000
Other financial assets	126,148,000	123,439,000
Demand and savings deposits	13,384,227,000	13,042,147,000
Brokered deposits	164,601,000	90,473,000
Time deposits	0	0
Short-term borrowings	485,565,000	617,524,000
Accrued interest payable	11,151,000	9,317,000
Other financial liabilities	176,429,000	188,555,000
Federal Home Loan Bank advances and long-term debt	0	0
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, FinancialStatement Captions[Line Items]
Cash and due from banks	0	0
Interest-bearing deposits with other banks	0	0
Federal Reserve Bank and Federal Home Loan Bank stock	65,926,000	60,761,000
Loans held for sale	27,525,000	31,530,000
Securities held to maturity	0
Estimated Fair Value	1,902,333,000
Available for sale investment securities		2,444,613,000
Net Loans	0	0
Accrued interest receivable	0	0
Other financial assets	67,079,000	44,539,000
Demand and savings deposits	0	0
Brokered deposits	0	0
Time deposits	2,684,783,000	2,664,912,000
Short-term borrowings	0	0
Accrued interest payable	0	0
Other financial liabilities	75,031,000	39,014,000
Federal Home Loan Bank advances and long-term debt	960,168,000	1,038,346,000
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, FinancialStatement Captions[Line Items]
Cash and due from banks	0	0
Interest-bearing deposits with other banks	0	0
Federal Reserve Bank and Federal Home Loan Bank stock	0	0
Loans held for sale	0	0
Securities held to maturity	0
Estimated Fair Value	106,483,000
Available for sale investment securities		102,425,000
Net Loans	15,124,455,000	15,380,974,000
Accrued interest receivable	0	0
Other financial assets	48,912,000	47,486,000
Demand and savings deposits	0	0
Brokered deposits	0	0
Time deposits	0	0
Short-term borrowings	0	0
Accrued interest payable	0	0
Other financial liabilities	0	0
Federal Home Loan Bank advances and long-term debt	$ 0	$ 0

Fair Value Measurements Narrati

Fair Value Measurements Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2017
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Securities valued by the pricing service	80.00%	80.00%
Researched securities to reconcile the difference	5.00%	5.00%
Available for sale, at estimated fair value	$ 2,008,816	$ 2,008,816
Significant input, assumed market return to liquidity (years)	5 years
Other real estate owned (OREO)	$ 10,684	$ 10,684	$ 9,823
Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Weighted average annual constant prepayment rate		8.80%
Weighted average discount rate		9.00%
Single-issuer Trust Preferred Securities [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available for sale, at estimated fair value	19,596	$ 19,596	30,703
Pooled Trust Preferred Securities [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available for sale, at estimated fair value	875	875	707
Fair Value, Measurements, Recurring [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available for sale, at estimated fair value	2,008,816	2,008,816
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available for sale, at estimated fair value	0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available for sale, at estimated fair value	1,902,333	1,902,333
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available for sale, at estimated fair value	106,483	106,483
Fair Value, Measurements, Recurring [Member] | Financial Institutions Subordinated Debt [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available for sale, at estimated fair value	67,900	67,900	61,900
Fair Value, Measurements, Recurring [Member] | Single-issuer Trust Preferred Securities [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available for sale, at estimated fair value	19,600	19,600	30,700
Fair Value, Measurements, Recurring [Member] | Single-issuer Trust Preferred Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available for sale, at estimated fair value	17,000	17,000	27,700
Fair Value, Measurements, Recurring [Member] | Single-issuer Trust Preferred Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available for sale, at estimated fair value	2,500	2,500	3,100
Fair Value, Measurements, Recurring [Member] | Pooled Trust Preferred Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available for sale, at estimated fair value	875	875	707
Fair Value, Measurements, Recurring [Member] | Other Corporate Debt [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Available for sale, at estimated fair value	4,000	4,000	4,000
Fair Value, Measurements, Recurring [Member] | Trust for Benefit of Employees [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other financial liabilities	20,000	20,000	19,000
Fair Value, Measurements, Recurring [Member] | Foreign Exchange Contract [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other financial liabilities	471	471	374
Foreign Exchange Contract [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other financial assets	529	529	460
Forward Commitments [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other financial assets	1,400	1,400	1,100
Other financial liabilities	77	77	272
Interest Rate Swap [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other financial assets	65,700	65,700	43,400
Other financial liabilities	$ 75,000	$ 75,000	$ 38,700