WesBanco (WSBC) 10-K 27 Feb 18 2017 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2017	Feb. 20, 2018	Jun. 30, 2017
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Trading Symbol	WSBC
Entity Registrant Name	WESBANCO INC
Entity Central Index Key	203,596
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		44,053,332
Entity Public Float			$ 1,630,100,029

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
ASSETS
Cash and due from banks, including interest bearing amounts of $19,826 and $21,913, respectively	$ 117,572	$ 128,170
Securities:
Trading securities, at fair value	7,844	7,071
Available-for-sale, at fair value	1,267,478	1,241,176
Held-to-maturity (fair values of $1,023,784 and $1,076,790, respectively)	1,009,500	1,067,967
Total securities	2,284,822	2,316,214
Loans held for sale	20,320	17,315
Portfolio loans, net of unearned income	6,341,441	6,249,436
Allowance for loan losses	(45,284)	(43,674)
Net portfolio loans	6,296,157	6,205,762
Premises and equipment, net	130,722	133,297
Accrued interest receivable	29,728	28,299
Goodwill and other intangible assets, net	589,264	593,187
Bank-owned life insurance	192,589	188,145
Other assets	155,004	180,488
Total Assets	9,816,178	9,790,877
Deposits:
Non-interest bearing demand	1,846,748	1,789,522
Interest bearing demand	1,625,015	1,546,890
Money market	1,024,856	995,477
Savings deposits	1,269,912	1,213,168
Certificates of deposit	1,277,057	1,495,822
Total deposits	7,043,588	7,040,879
Federal Home Loan Bank borrowings	948,203	968,946
Other short-term borrowings	184,805	199,376
Subordinated debt and junior subordinated debt	164,327	163,598
Total borrowings	1,297,335	1,331,920
Accrued interest payable	3,178	2,204
Other liabilities	76,756	74,466
Total Liabilities	8,420,857	8,449,469
SHAREHOLDERS' EQUITY
Preferred Stock, no par value; 1,000,000 shares authorized; none outstanding
Common stock, $2.0833 par value; 100,000,000 shares authorized; 44,043,244 and 43,931,715 shares issued in 2017 and 2016, respectively; 44,043,244 and 43,931,715 shares outstanding in 2017 and 2016, respectively	91,756	91,524
Capital surplus	684,730	680,507
Retained earnings	651,357	597,071
Treasury stock (0 shares in 2017 and 2016, respectively, at cost)	0	0
Accumulated other comprehensive loss	(31,495)	(27,126)
Deferred benefits for directors	(1,027)	(568)
Total Shareholders' Equity	1,395,321	1,341,408
Total Liabilities and Shareholders' Equity	$ 9,816,178	$ 9,790,877

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Interest bearing deposits, banks	$ 19,826	$ 21,913
Held-to-maturity securities, fair values	$ 1,023,784	$ 1,076,790
Preferred stock, no par value
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 2.0833	$ 2.0833
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	44,043,244	43,931,715
Common stock, shares outstanding	44,043,244	43,931,715
Treasury stock, shares	0	0

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
INTEREST AND DIVIDEND INCOME
Loans, including fees	$ 272,007	$ 226,993	$ 203,993
Interest and dividends on securities:
Taxable	38,631	38,490	39,314
Tax-exempt	19,489	18,390	16,764
Total interest and dividends on securities	58,120	56,880	56,078
Other interest income	2,297	2,224	1,641
Total interest and dividend income	332,424	286,097	261,712
INTEREST EXPENSE
Interest bearing demand deposits	6,452	2,817	1,943
Money market deposits	2,775	1,860	1,914
Savings deposits	745	696	640
Certificates of deposit	10,108	10,419	11,033
Total interest expense on deposits	20,080	15,792	15,530
Federal Home Loan Bank borrowings	13,290	11,985	5,510
Other short-term borrowings	1,442	478	370
Subordinated debt and junior subordinated debt	7,317	4,512	3,315
Total interest expense	42,129	32,767	24,725
NET INTEREST INCOME	290,295	253,330	236,987
Provision for credit losses	9,986	8,478	8,353
Net interest income after provision for credit losses	280,309	244,852	228,634
NON-INTEREST INCOME
Trust fees	22,740	21,630	21,900
Service charges on deposits	20,532	18,333	16,743
Electronic banking fees	19,183	15,596	14,361
Net securities brokerage revenue	6,672	6,449	7,692
Bank-owned life insurance	4,794	4,064	4,863
Mortgage banking income	5,053	2,529	2,071
Net securities gains	567	2,357	948
Net gain on other real estate owned and other assets	658	790	356
Other income	8,641	9,751	5,532
Total non-interest income	88,840	81,499	74,466
NON-INTEREST EXPENSE
Salaries and wages	97,361	84,281	77,340
Employee benefits	29,933	27,952	26,896
Net occupancy	17,101	14,664	13,635
Equipment	16,026	14,543	13,194
Marketing	5,720	5,391	5,646
FDIC insurance	3,504	3,990	4,107
Amortization of intangible assets	4,940	3,598	3,136
Restructuring and merger-related expense	945	13,261	11,082
Other operating expenses	45,330	41,000	38,887
Total non-interest expense	220,860	208,680	193,923
Income before provision for income taxes	148,289	117,671	109,177
Provision for income taxes	53,807	31,036	28,415
NET INCOME	$ 94,482	$ 86,635	$ 80,762
EARNINGS PER COMMON SHARE
Basic	$ 2.15	$ 2.16	$ 2.15
Diluted	$ 2.14	$ 2.16	$ 2.15
AVERAGE COMMON SHARES OUTSTANDING
Basic	44,003,208	40,100,320	37,488,331
Diluted	44,075,293	40,127,076	37,547,127
DIVIDENDS DECLARED PER COMMON SHARE	$ 1.04	$ 0.96	$ 0.92

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 94,482	$ 86,635	$ 80,762
Securities available-for-sale:
Net change in unrealized (losses) on securities available-for-sale	(1,702)	(6,761)	(10,552)
Related income tax benefit	717	2,461	3,875
Net securities gains reclassified into earnings	(42)	(2,251)	(596)
Related income tax expense	15	823	219
Net effect on other comprehensive income for the period	(1,012)	(5,728)	(7,054)
Securities held-to-maturity:
Amortization of unrealized gain transferred from available-for-sale	(326)	(357)	(494)
Related income tax expense	117	132	182
Net effect on other comprehensive income for the period	(209)	(225)	(312)
Defined benefit pension plan:
Amortization of net loss and prior service costs	3,247	3,046	3,205
Related income tax benefit	(1,053)	(1,153)	(1,201)
Recognition of unrealized gain (loss)	380	(3,329)	5,106
Related income tax (expense) benefit	(141)	1,217	(1,873)
Net effect on other comprehensive income for the period	2,433	(219)	5,237
Total other comprehensive gain (loss)	1,212	(6,172)	(2,129)
Comprehensive income	$ 95,694	$ 80,463	$ 78,633

Consolidated Statements of Chan

Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Capital Surplus [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Loss [Member]	Deferred Benefits for Directors [Member]
Beginning Balance at Dec. 31, 2014	$ 788,190	$ 61,182	$ 244,661	$ 504,578	$ (2,151)	$ (18,825)	$ (1,255)
Beginning Balance, shares at Dec. 31, 2014		29,298,188
Net income	80,762			80,762
Other comprehensive gain (loss)	(2,129)					(2,129)
Comprehensive income	78,633
Common dividends declared ($0.92, $0.96, and $1.04 per share for the year ended Dec. 31, 2015, 2016, and 2017 respectively)	(35,419)			(35,419)
Shares issued for acquisition	293,629	$ 19,122	274,507
Shares issued for acquisition, shares		9,178,531
Stock options exercised	1,601		(324)		1,925
Stock options exercised, shares		60,275
Restricted stock granted			(1,558)		1,558
Restricted stock granted, Shares		49,550
Repurchase of stock warrant	(2,247)		(2,247)
Treasury shares acquired	(3,921)		51		(3,972)
Treasury shares acquired, shares		(126,909)
Stock compensation expense	1,666		1,666
Deferred benefits for directors - net			(462)				462
Ending Balance at Dec. 31, 2015	1,122,132	$ 80,304	516,294	549,921	(2,640)	(20,954)	(793)
Ending Balance, shares at Dec. 31, 2015		38,459,635
Net income	86,635			86,635
Other comprehensive gain (loss)	(6,172)					(6,172)
Comprehensive income	80,463
Common dividends declared ($0.92, $0.96, and $1.04 per share for the year ended Dec. 31, 2015, 2016, and 2017 respectively)	(39,485)			(39,485)
Shares issued for acquisition	177,149	$ 11,071	162,934		3,144
Shares issued for acquisition, shares		5,423,348
Stock options exercised	2,920	$ 139	1,707		1,074
Stock options exercised, shares		101,190
Restricted stock granted		$ 10	(2,281)		2,271
Restricted stock granted, Shares		81,220
Treasury shares acquired	(3,793)		56		(3,849)
Treasury shares acquired, shares		(133,678)
Stock compensation expense	2,022		2,022
Deferred benefits for directors - net			(225)				225
Ending Balance at Dec. 31, 2016	1,341,408	$ 91,524	680,507	597,071		(27,126)	(568)
Ending Balance, shares at Dec. 31, 2016		43,931,715
Net income	94,482			94,482
Other comprehensive gain (loss)	1,212					1,212
Comprehensive income	95,694
Common dividends declared ($0.92, $0.96, and $1.04 per share for the year ended Dec. 31, 2015, 2016, and 2017 respectively)	(45,777)			(45,777)
Adoption of accounting standard				5,581		(5,581)
Stock options exercised	$ 1,529	$ 78	794		657
Stock options exercised, shares	53,584	54,584
Restricted stock granted		$ 154	(154)
Restricted stock granted, Shares		74,023
Treasury shares acquired	$ (489)		168		$ (657)
Treasury shares acquired, shares		(17,078)
Stock compensation expense	2,956		2,956
Deferred benefits for directors - net			459				(459)
Ending Balance at Dec. 31, 2017	$ 1,395,321	$ 91,756	$ 684,730	$ 651,357		$ (31,495)	$ (1,027)
Ending Balance, shares at Dec. 31, 2017		44,043,244

Consolidated Statements of Cha7

Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Stockholders' Equity [Abstract]
Common dividends declared, per share	$ 1.04	$ 0.96	$ 0.92

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
OPERATING ACTIVITIES
Net income	$ 94,482	$ 86,635	$ 80,762
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of premises and equipment	10,441	9,242	8,122
Other net amortization	8,871	8,768	6,460
Provision for credit losses	9,986	8,478	8,353
Net securities gains	(567)	(2,357)	(948)
Net gains on sales of mortgage loans	(5,053)	(2,529)	(2,071)
Stock compensation expense	2,956	2,022	1,666
Decrease in deferred income tax assets, net	27,112	10,824	10,665
Increase in cash surrender value of bank-owned life insurance	(4,794)	(4,064)	(4,863)
Contribution to pension plan	(5,000)	(5,750)	(7,500)
Loans originated for sale	(216,744)	(167,370)	(135,892)
Proceeds from the sale of loans originated for sale	213,610	159,831	135,928
Increase in trading securities	(773)	(620)	(263)
Net change in: accrued interest receivable and other assets	4,593	13,137	(4,293)
Net change in: accrued interest payable and other liabilities	2,944	7,404	(7,988)
Other-net	(438)	(574)	248
Net cash provided by operating activities	141,626	123,077	88,386
INVESTING ACTIVITIES
Net increase in loans held for investment	(90,225)	(174,952)	(293,306)
Securities available-for-sale:
Proceeds from sales	7,760	277,225	635,609
Proceeds from maturities, prepayments and calls	211,383	285,318	319,370
Purchases of securities	(252,314)	(213,894)	(526,502)
Securities held-to-maturity:
Proceeds from maturities, prepayments and calls	118,180	110,954	75,295
Purchases of securities	(66,473)	(93,444)	(390,471)
Net cash received (paid) to acquire a business		4,863	(28,551)
Proceeds from bank-owned life insurance	349	19	7,803
Purchases of premises and equipment-net	(6,035)	(2,061)	(9,575)
Sale of portfolio loans-net		560
Net cash (used in) provided by investing activities	(77,375)	194,588	(210,328)
FINANCING ACTIVITIES
Increase (decrease) in deposits	4,262	(216,785)	(233,684)
Proceeds from Federal Home Loan Bank borrowings	680,000	140,000	941,910
Repayment of Federal Home Loan Bank borrowings	(700,716)	(233,988)	(515,388)
Increase (decrease) in other short-term borrowings	18,429	15,711	(4,334)
(Decrease) increase in federal funds purchased	(33,000)	58,000
Repayment of junior subordinated debt			(36,083)
Repurchase of common stock warrant			(2,247)
Dividends paid to common shareholders	(44,864)	(37,805)	(33,007)
Issuance of common stock	1,040	1,713
Treasury shares purchased-net		(3,026)	(2,542)
Net cash (used in) provided by financing activities	(74,849)	(276,180)	114,625
Net (decrease) increase in cash and cash equivalents	(10,598)	41,485	(7,317)
Cash and cash equivalents at beginning of the year	128,170	86,685	94,002
Cash and cash equivalents at end of the year	117,572	128,170	86,685
SUPPLEMENTAL DISCLOSURES
Interest paid on deposits and other borrowings	42,534	34,028	27,969
Income taxes paid	22,875	22,075	15,855
Transfers of loans to other real estate owned	$ 635	4,757	1,501
Transfers of portfolio loans to loans held for sale		560
Non-cash transactions related to YCB and ESB acquisitions		$ 177,149	$ 301,933

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	NOTE 1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Nature of Operations— Use of Estimates— Principles of Consolidation— WesBanco determines whether it has a controlling financial interest in an entity by first evaluating whether the entity is a voting interest entity or a variable interest entity. A voting interest entity is an entity in which the total equity investment at risk is sufficient to enable the entity to finance itself independently and provides the equity holders with the obligation to absorb losses, the right to receive residual returns and the right to make financial and operating decisions. WesBanco consolidates voting interest entities in which it owns all, or at least a majority (generally, greater than 50%) of the voting interest. Variable Interest Entities— A controlling financial interest in a VIE is present when an enterprise has both the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and the obligation to absorb losses of the VIE that could potentially be significant to the VIE or the right to receive benefits of the VIE that could potentially be significant to the VIE. A VIE often holds financial assets, including loans or receivables, real estate or other property. The company with a controlling financial interest, known as the primary beneficiary, is required to consolidate the VIE. WesBanco has twelve wholly-owned trust subsidiaries (collectively, the “Trusts”), for which it does not absorb a majority of expected losses or receive a majority of the expected residual returns. Accordingly, the Trusts and their net assets are not included in the Consolidated Financial Statements. However, the junior subordinated deferrable interest debentures issued by WesBanco to the Trusts (refer to Note 11, “Subordinated Debt and Junior Subordinated Debt”) and the common stock issued by the Trusts is included in the Consolidated Balance Sheets. WesBanco also owns non-controlling variable interests in certain limited partnerships for which it does not absorb a majority of expected losses or receive a majority of expected residual returns. These VIEs are not consolidated into WesBanco’s financial statements because WesBanco is not considered the primary beneficiary. These investments are accounted for using the equity method of accounting and are included in other assets in the Consolidated Balance Sheets. Refer to Note 8, “Investments in Limited Partnerships” for further detail. Revenue Recognition— Cash and Cash Equivalents— Securities— Trading securities: Available-for-sale securities: Held-to-maturity securities: Cost method investments: Securities acquired in acquisitions are recorded at fair value with the premium or discount derived from the fair market value adjustment recognized into interest income on a level yield basis over the remaining life of the security. Gains and losses: Amortization and accretion: Other-than-temporary impairment losses: Loans and Loans Held for Sale— Performing loans acquired in acquisitions are recorded at fair value with no carryover of related allowance for credit losses. The premium or discount derived from the fair market value adjustment is recognized into interest income using a level yield method over the remaining expected life of the loan. Refer to the “Acquired Loans” policy below for additional detail. Loan origination fees and direct costs are deferred and accreted or amortized into interest income, as an adjustment to the yield, over the life of the loan using the level yield method. When a loan is paid off, the remaining unaccreted or unamortized net origination fees or costs are immediately recognized into income. Loans are generally placed on non-accrual when they are 90 days past due, unless the loan is well-secured and in the process of collection. Loans may be returned to accrual status when a borrower has resumed paying principal and interest for a sustained period of at least six months and the Bank is reasonably assured of collecting the remaining contractual principal and interest. Loans are returned to accrual status at an amount equal to the principal balance of the loan at the time of non-accrual status less any payments applied to principal during the non-accrual period. Loans are reported as a troubled debt restructuring when WesBanco for economic or legal reasons related to a borrower’s financial difficulties grants a concession to the borrower that it would not otherwise consider. Refer to the “Troubled Debt Restructuring” policy below for additional detail. A loan is considered impaired, based on current information and events, if it is probable that WesBanco will be unable to collect the payments of principal and interest when due according to the contractual terms of the loan agreement. Impaired loans include all non-accrual loans and troubled debt restructurings. WesBanco recognizes interest income on non-accrual loans on the cash basis only if recovery of principal is reasonably assured. Consumer loans are charged down to the net realizable value at 120 days past due for closed-end loans and 180 days past due for open-end revolving lines of credit. Residential real estate loans are charged down to the net realizable value of the collateral at 180 days past due. Commercial loans are charged down to the net realizable value when it is determined that WesBanco will be unable to collect the principal amount in full. Loans are reclassified to other assets at the net realizable value when foreclosure or repossession of the collateral occurs. Refer to the “Other Real Estate Owned and Repossessed Assets” policy below for additional detail. Troubled Debt Restructurings (“TDR”)— When determining whether a debtor is experiencing financial difficulties, consideration is given to any known default on any of its debt or whether it is probable that the debtor would be in payment default in the foreseeable future without the modification. Other indicators of financial difficulty include whether the debtor has declared or is in the process of declaring bankruptcy, the debtor’s ability to continue as a going concern, or the debtor’s projected cash flow to service its debt (including principal & interest) in accordance with the contractual terms for the foreseeable future, without a modification. If the payment of principal at original maturity is primarily dependent on the value of collateral, the current value of that collateral is considered in determining whether the principal will be paid. The restructuring of a loan does not have a material effect on the allowance or provision for credit losses as the internal risk grade of a loan has more influence on the allowance than the classification of a loan as a TDR. The internal risk rating is the primary factor for establishing the allowance for commercial loans, including commercial real estate except for loans that are individually evaluated for impairment, in which case a specific reserve is established pursuant to GAAP. Portfolio segment loss history is the primary factor for establishing the allowance for residential real estate, home equity and consumer loans. Non-accrual loans that are restructured remain on non-accrual, but may move to accrual status after they have performed according to the restructured terms for a period of time. TDRs on accrual status generally remain on accrual as long as they continue to perform in accordance with their modified terms. TDRs may also be placed on non-accrual if they do not perform in accordance with the restructured terms. Loans may be removed from TDR status after they have performed according to the renegotiated terms for a period of time if the interest rate under the modified terms is at or above market, or if the loan returns to its original terms. Acquired Loans Acquired loans that meet the criteria for non-accrual of interest prior to acquisition are considered to be performing upon acquisition, regardless of whether the customer is contractually delinquent, if WesBanco can reasonably estimate the timing and amount of expected cash flows on such loans. Accordingly, WesBanco does not consider acquired contractually delinquent loans to be non-accrual or non-performing and continues to recognize interest income on these loans using the accretion method. Loans acquired with deteriorated credit quality are accounted for in accordance with Accounting Standards Codification (“ASC”) 310-30, Loans and Debt Securities Acquired with Deteriorated Credit Quality (ASC 310-30) if, at acquisition, the loans have evidence of credit quality deterioration since origination and it is probable that all contractually required payments will not be collected. At acquisition, WesBanco considers several factors as indicators that an acquired loan has evidence of deterioration in credit quality. These factors include loans 90 days or more past due, loans with an internal risk grade of substandard or below, loans classified as non-accrual by the acquired institution, and loans that have been previously modified in a troubled debt restructuring. Under the ASC 310-30 model, the excess of cash flows expected to be collected at acquisition over recorded fair value is referred to as the accretable yield and is the interest component of expected cash flow. The accretable yield is recognized into income over the remaining life of the loan if the timing and/or amount of cash flows expected to be collected can be reasonably estimated (the accretion method). If the timing or amount of cash flows expected to be collected cannot be reasonably estimated, the cost recovery method of income recognition is used. The difference between the loan’s total scheduled principal and interest payments over all cash flows expected to be collected at acquisition, considering the impact of prepayments, is referred to as the non-accretable difference. The non-accretable difference represents contractually required principal and interest payments which WesBanco does not expect to collect. Over the life of the loan, management continues to estimate cash flows expected to be collected for ASC 310-30 loans. Decreases in expected cash flows are recognized as impairments through a charge to the provision for loan losses resulting in an increase in the allowance for loan losses. Subsequent improvements in cash flows result in first, reversal of existing valuation allowances recognized subsequent to acquisition, if any, and next, an increase in the amount of accretable yield to be subsequently recognized in interest income on a prospective basis over the loan’s remaining life. Acquired loans that were not individually determined to be purchased with deteriorated credit quality are accounted for in accordance with ASC 310-20, Nonrefundable Fees and Other Costs (ASC 310-20), whereby the premium or discount derived from the fair market value adjustment, on a loan-by-loan or pooled basis, is recognized into interest income on a level yield basis over the remaining expected life of the loan or pool. Allowance for Credit Losses— The evaluation includes an assessment of quantitative factors such as actual loss experience within each category of loans and testing of certain commercial loans for impairment. The evaluation also considers qualitative factors such as economic trends and conditions, which includes levels of unemployment, real estate values and the impact on specific industries and geographical markets, changes in lending policies and underwriting standards, delinquency and other credit quality trends, concentrations of credit risk, if any, the results of internal loan reviews and examinations by bank regulatory agencies, the volatility of historical loss rates and the velocity of changes in historical loss rates pertaining to the allowance for credit losses. Management relies on observable data from internal and external sources to the extent it is available to evaluate each of these factors and adjusts the actual historical loss rates to reflect the impact these factors may have on probable losses in the portfolio. Commercial real estate and commercial and industrial loans greater than $1 million that are reported as non-accrual or as a troubled debt restructuring are tested individually for impairment. Specific reserves are established when appropriate for such loans based on the present value of expected future cash flows of the loan or the estimated realizable value of the collateral, if any. General reserves are established for loans that are not individually tested for impairment based on historical loss rates adjusted for the impact of the qualitative factors discussed above. Historical loss rates for commercial real estate and commercial and industrial loans are determined for each internal risk grade or group of pass grades using a migration analysis. Residential real estate, home equity and consumer loans are not risk graded, so historical loss rates are utilized to determine the total of each category of loans. Historical loss rates for deposit account overdrafts are based on actual losses in relation to average overdrafts for the period. Management may also adjust its assumptions to account for differences between estimated and actual incurred losses from period to period. The variability of management’s assumptions could alter the level of the allowance for credit losses and may have a material impact on future results of operations and financial condition. The loss estimation models and methods used to determine the allowance for credit losses are continually refined and enhanced; however, there have been no material substantive changes compared to prior periods. Premises and Equipment— Other Real Estate Owned and Repossessed Assets— Goodwill and Other Intangible Assets— Goodwill is not amortized but is evaluated for impairment annually, or more often if events or circumstances indicate it may be impaired. Finite-lived intangible assets, which consist primarily of core deposit and customer list intangibles (long-term customer-relationship intangible assets) are amortized using straight-line and accelerated methods over their weighted-average estimated useful lives, ranging from ten to sixteen years in total, and are tested for impairment whenever events or circumstances indicate that their carrying amount may not be recoverable. Non-compete agreements are recognized in other assets on the balance sheet and are amortized on a straight-line basis over the life of the respective agreements, ranging from one to four years. Goodwill is evaluated for impairment by either assessing qualitative factors to determine whether it is necessary to perform the goodwill impairment test, or WesBanco may elect to perform the goodwill impairment test. Under the qualitative assessment, WesBanco assesses qualitative factors to determine whether it is more likely than not that the fair value of its reporting units are less than their carrying amounts, including goodwill. If it is more likely than not, the goodwill impairment test is used to identify potential goodwill impairment and measure the amount of a goodwill impairment loss to be recognized, if any. The estimated fair value of each reporting unit is compared to its carrying value, including goodwill. If the estimated fair value of a reporting unit exceeds its carrying amount, the goodwill of that reporting unit is not considered impaired, and no impairment loss is recognized. However, if the carrying amount of the reporting unit exceeds its fair value, an impairment loss is recognized based on the excess of a reporting unit’s carrying value over its fair value. Intangible assets with finite useful lives are evaluated for impairment whenever events or changes in circumstances indicate that their carrying amount may not be recoverable. An impairment loss is recognized when the carrying amount of an intangible asset with a finite useful life is not recoverable from its undiscounted cash flows and is measured as the difference between the carrying amount and the fair value of the asset. WesBanco does not have any indefinite-lived intangible assets. Bank-Owned Life Insurance— Interest Rate Lock Commitments— A mortgage loan sold on a mandatory basis is sold to the secondary market when the mortgage loan is funded. WesBanco enters into TBA contracts in order to control interest rate risk during the period between the IRLC and the sale of the mortgage loan. The IRLC is executed between the mortgagee and WesBanco, and the forward TBA contract is executed between WesBanco and a counterparty. Both the IRLC and the forward TBA contract is considered a derivative. Both types of derivatives are recorded at fair value and are not designated in a qualified hedged accounting program. The changes in fair value are recorded in current earnings within mortgage banking income in the Consolidated Statements of Income. The fair value of IRLC is the gain or loss that would be realized on the underlying loans assuming exercise of the commitments under current market rates versus the rate incorporated in the commitments, taking into consideration fallout. The fair value of forward TBA contracts is based on quoted market prices. Since loans typically close before receipt of funding from an investor, they are accounted for at fair value as “Loans Held for Sale” in the Consolidated Balance Sheets. A mortgage loan sold on a best efforts basis is locked into a forward sales contract on the same day as the IRLC to control interest rate risk during the period between the IRLC and the sale of the mortgage loan. The IRLC is executed between the mortgagee and WesBanco, and the forward sales contract is executed between WesBanco and a counterparty. Both the IRLC and the forward sales contract are considered a derivative. Both types of derivatives are recorded at fair value and are not designated in a qualified hedged accounting program. The changes in fair value are recorded in current earnings within mortgage banking income in the Consolidated Statements of Income. The fair value of IRLC is the gain or loss that would be realized on the underlying loans assuming exercise of the commitments under current market rates versus the rate incorporated in the commitments, taking into consideration fallout. The fair value of forward sales contracts is based on quoted market prices. Since loans typically close before receipt of funding from an investor, they are accounted for at fair value as “Loans Held for Sale” in the Consolidated Balance Sheets. Derivative Instruments and Hedging Activities— Income Taxes— Fair Value— Level 1—Quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; Level 2—Quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, or model-based valuation techniques where all significant assumptions are observable, either directly or indirectly, in the market; Level 3—Valuation is generated from model-based techniques where one or more significant assumptions are not observable, either directly or indirectly, in the market. These unobservable assumptions reflect our own estimates of assumptions that market participants would use in pricing the asset or liability. Valuation techniques may include use of discounted cash flow models and similar techniques. A financial instrument’s level within the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement. Earnings Per Common Share— Trust Assets— Stock-Based Compensation— Defined Benefit Pension Plan Recent accounting pronouncements— In August 2017, the FASB issued ASU No. 2017-12, Targeted Improvements to Accounting for Hedging Activities.” The new guidance will make more financial and nonfinancial hedging strategies eligible for hedge accounting. It also amends the presentation and disclosure requirements and changes how companies assess effectiveness. It is intended to more closely align hedge accounting with companies’ risk management strategies, simplify the application of hedge accounting, and increase transparency as to the scope and results of hedging programs. The guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption is permitted, including adoption in an interim period. WesBanco is assessing the impact of ASU 2017-12 and does not expect it to have a material impact on WesBanco’s Consolidated Financial Statements. In May 2017, the FASB issued ASU No. 2017-09 that provides guidance on determining which changes to the terms and conditions of share-based payment awards require an entity to apply modification accounting under Topic 718. The guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017. Early adoption is permitted, including adoption in an interim period. The amendments should be applied on a prospective basis to an award modified on or after the adoption date. The adoption of this pronouncement did not have a material impact on WesBanco’s Consolidated Financial Statements. In March 2017, FASB issued ASU 2017-08 that shortens the amortization period of certain callable debt securities held at a premium. The premium is required to be amortized to the earliest call date. Securities held at a discount continue to be amortized to maturity. Public business entities must apply the new requirements for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, which for WesBanco will be effective for the fiscal year beginning January 1, 2019. Early adoption is permitted. The adoption of this pronouncement did not have a material impact on WesBanco’s Consolidated Financial Statements. In March 2017, the FASB issued ASU 2017-07 that changes how an employer presents the net periodic benefit cost in the income statement for an employer-sponsored defined benefit pension and/or other postretirement benefit plans. Employers will present the service cost component of net periodic benefit cost in the same income statement line item as other employee compensation costs arising from services rendered during the period. Only the service cost component will be eligible for capitalization in assets. Employers will present the other components of the net periodic benefit cost separately from the line items that includes the service cost outside of any subtotal of operating income, if one is presented. These components will not be eligible for capitalization in assets. For public business entities, the amendments in this update are effective for annual reporting periods beginning after December 15, 2017, including interim reporting periods within those annual reporting periods. Early adoption is permitted as of the beginning of an annual period (i.e., only in the first interim period). For WesBanco, this update will be effective for the fiscal year beginning January 1, 2018. Upon adoption, WesBanco will reclassify the service cost component from employee benefits to salaries and wages, which are both components of non-interest expense. The service cost component for the twelve months ending December 31, 2017 was $2.6 million. In January 2017, the FASB issued ASU 2017-04 that eliminated the requirement to calculate the implied fair value of goodwill to measure a goodwill impairment charge. Instead, entities will record an impairment charge based on the excess of a reporting unit’s carrying amount over its fair value. Public business entities that are a U.S. Securities and Exchange Commission (“SEC”) filer should adopt this update for its annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019, which for WesBanco will be effective for the fiscal year beginning January 1, 2020. Early adoption is permitted. The adoption of this pronouncement did not have a material impact on WesBanco’s Consolidated Financial Statements. In January 2017, the FASB issued ASU No. 2017-01, which clarifies the definition of a business with the objective of adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. ASU 2017-01 will be effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017, which for WesBanco will be effective for the fiscal year beginning January 1, 2018. WesBanco is currently evaluating the potential impact of ASU 2017-01 but it is not expected that the adoption of this new standard will have a material impact on WesBanco’s Consolidated Financial Statements. In October 2016, the FASB issued ASU 2016-16 that provides the recognition of income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. Current guidance prohibits the recognition of current and deferred income taxes for an intra-entity asset transfer until the asset has been sold to an outside party. This prohibition on recognition is an exception to the principle of comprehensive recognition of current and deferred income taxes in generally accepted accounting principles. The exception has led to diversity in practice and is a source of complexity in financial reporting. FASB decided that an entity should recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. Consequently, the amendments in this update eliminate the exception for an intra-entity transfer of an asset other than inventory. The amendments in this update do not include new disclosure requirements; however, existing disclosure requirements might be applicable when accounting for the current and deferred income taxes for an intra-entity transfer of an asset other than inventory. For public business entities, the amendments in this update are effective for annual reporting periods beginning after December 15, 2017, including interim reporting periods within those annual reporting periods, which for WesBanco will be effective for the fiscal year beginning January 1, 2018. The amendments in this update should be applied on a modified retrospective basis through a cumulative-effect adjustment directly to retained earnings as of the beginning of the period of adoption. The adoption of this pronouncement is not expected to have a material impact on WesBanco’s Consolidated Financial Statements. In August 2016, the FASB issued ASU 2016-15 that provides guidance for the classification of cash flows related to (1) debt prepayment or extinguishment costs, (2) settlement of zero-coupon debt instruments or other debt instruments with coupon rates that are insignificant in relation to the effective interest rate on the borrowing, (3) contingent consideration payments made after a business combination, (4) proceeds from the settlement of insurance claims, (5) proceeds from the settlement of corporate-owned life insurance policies, (6) distributions received from equity method investees, (7) beneficial interests in securitization transactions and (8) separately identifiable cash flows and application of the predominance principle. Public business entities must apply the new requirements for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years, which for WesBanco will be effective for the fiscal year beginning January 1, 2018. Early adoption is permitted. The adoption of this pronouncement is not expected to have a material impact on WesBanco’s Consolidated Financial Statements. In June 2016, the FASB issued ASU 2016-13 that will require entities to use a new forward-looking “expected loss” model on trade and other receivables, held-to-maturity debt securities, loans and other instruments that generally will result in the earlier recognition of allowances for credit losses. For available-for-sale debt securities with unrealized losses, entities will measure credit losses in a manner similar to what they do today, except that the losses will be recognized as allowances rather than reductions in the amortized cost of the securities. Entities will have to disclose significantly more information, including information they use to track credit quality by year of origination for most financing receivables. Public business entities must apply the new requirements for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, which for WesBanco will be effective for the fiscal year beginning January 1, 2020. Early adoption is permitted for fiscal years beginning after December 15, 2018. WesBanco is currently evaluating the impact of the adoption of this pronouncement on WesBanco’s Consolidated Financial Statements. In March 2016, the FASB issued ASU 2016-09 that will require all excess income tax benefits or tax deficiencies of stock awards to be recognized in the income statement when the awards vest or are settled. It also will allow an employer to repurchase more of an employee’s shares than it can today for tax withholding purposes without triggering liability accounting and to make a policy election to account for forfeitures as they occur. Public business entities must apply the new requirements for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. WesBanco made a policy election to account for forfeitures as they occur rather than estimating them over the life of the award. The adoption of this pronouncement did not have a material impact on WesBanco’s Consolidated Financial Statements. In March 2016, the FASB issued ASU 2016-07 that eliminates the requirement to retrospectively apply the equity method in previous periods when an investor initially obtains significant influence over an investee. The update is effective for interim and annual reporting periods in fiscal years beginning after December 15, 2016, and requires prospective adoption. Early adoption is permitted. The adoption of this pronouncement did not have a material impact on WesBanco’s Consolidated Financial Statements. In February 2016, the FASB issued ASU 2016-02 that will require entities to recognize lease assets and lease liabilities on the balance sheet and disclose key information about leasing arrangements. The principal difference from previous guidance is that the lease assets and lease liabilities arising from operating leases were not previously recognized in the balance sheet. Public business entities must apply the new requirements for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted. While we are currently assessing the impact of the adoption of this pronouncement, we expect the primary impact to our consolidated financial position upon adoption will be the recognition, on a discounted basis, of our minimum commitments under non-cancellable operating leases on our consolidated Balance Sheets resulting in the recording of right of use assets and lease obligations. Our current minimum commitments under non-cancellable operating leases are disclosed in Note 6, “Premises and Equipment”. In January 2016, the FASB issued ASU 2016-01 that will require entities to measure equity investments that do not result in consolidation and are not accounted for under the equity method at fair value and recognize any changes in fair value in net income unless the investments qualify for the new practicability exception. The standard does not change the guidance for classifying and measuring investments in debt securities and loans. Entities will have to record changes in instrument-specific credit risk for financial liabilities measured under the fair value option in other comprehensive income. Public business entities must apply the new requirements for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. Early adoption is permitted. The adoption of this pronouncement is not expected to have a material impact on WesBanco’s Consolidated Financial Statements. In May 2014, the FASB issued ASU 2014-09 related to the recognition of revenue from contracts with customers. The new revenue pronouncement creates a single source of revenue guidance for all companies in all industries and is more principles-based than current revenue guidance. The pronouncement provides a five-step model for a company to recognize revenue when it transfers control of goods or services to customers at an amount that reflects the consi

Mergers and Acquisitions

Mergers and Acquisitions	12 Months Ended
	Dec. 31, 2017
Business Combinations [Abstract]
Mergers and Acquisitions	NOTE 2. MERGERS AND ACQUISITIONS On November 13, 2017, WesBanco and First Sentry Bancshares, Inc. (“FTSB”), a bank holding company headquartered in Huntington, West Virginia which, as of September 30, 2017, had approximately $658.2 million in assets excluding goodwill, $527.6 million in total deposits, $402.4 million in total loans and five branches in West Virginia, entered into a definitive Agreement and Plan of Merger. The transaction will enhance WesBanco’s position in the Huntington, West Virginia Metropolitan Statisical Area. The transaction, valued approximately at $101.4 million, is scheduled to close early in April 2018. The acquisition was subject to approval by the appropriate banking regulatory authorities and the shareholders of FTSB, and such approvals were obtained in February 2018. On September 9, 2016, WesBanco completed its acquisition of Your Community Bankshares, Inc. (“YCB”), and its wholly-owned banking subsidiary, Your Community Bank (“YCB Bank”), an Indiana state-chartered commercial bank headquartered in New Albany, Indiana. The transaction expanded WesBanco’s franchise into Kentucky and southern Indiana. On the acquisition date, YCB had $1.5 billion in total assets, excluding goodwill, including $1.0 billion in loans and $173.2 million in securities. The YCB acquisition was valued at $220.5 million, based on WesBanco’s closing stock price on September 9, 2016 of $32.62, and resulted in WesBanco issuing 5,423,348 shares of its common stock and $43.3 million in cash in exchange for all of the outstanding shares of YCB common stock. The assets and liabilities of YCB were recorded on WesBanco’s balance sheet at their fair value as of September 9, 2016, the acquisition date, and YCB’s results of operations have been included in WesBanco’s Consolidated Statements of Income since that date. Based on the final purchase price allocation, WesBanco recorded $93.0 million in goodwill and $12.0 million in core deposit intangibles in its Community Banking segment, representing the principal change in goodwill and intangibles in 2016. None of the goodwill is deductible for income tax purposes, as the acquisition is accounted for as a tax-free exchange for tax purposes. For the years ended December 31, 2017 and 2016, WesBanco recorded merger-related expenses of $0.5 million and $13.3 million, respectively, associated with the YCB acquisition. The final purchase price of the YCB acquisition and resulting goodwill is summarized as follows: (in thousands) September 9, 2016 Purchase Price: Fair value of WesBanco shares issued $ 177,149 Cash consideration for outstanding YCB shares 43,349 Total purchase price $ 220,498 Fair value of: Tangible assets acquired $ 1,398,183 Core deposit and other intangible assets acquired 11,957 Liabilities assumed (1,330,887 ) Net cash received in the acquisition 48,212 Fair value of net assets acquired $ 127,465 Goodwill recognized $ 93,033 The following table presents the allocation of the purchase price of the assets acquired and the liabilities assumed at the date of acquisition. (in thousands) September 9, 2016 Assets acquired Cash and due from banks $ 48,212 Securities 173,223 Loans 1,012,410 Goodwill and other intangible assets 104,990 Accrued income and other assets (1) 212,550 Total assets acquired $ 1,551,385 Liabilities assumed Deposits $ 1,193,010 Borrowings 123,001 Accrued expenses and other liabilities 14,876 Total liabilities assumed 1,330,887 Net assets acquired $ 220,498 (1) Includes receivables of $105.8 million from the sale of available-for-sale securities prior to the acquisition date. The following table presents the changes in the allocation of the purchase price of the assets acquired and the liabilities assumed at the date of the acquisition previously reported as of December 31, 2016: (in thousands) September 9, 2016 Goodwill recognized as of December 31, 2016 $ 92,889 Change in fair value of net assets acquired: Assets Loans (1,156 ) Accrued income and other assets 743 Liabilities Borrowings — Accrued expenses and other liabilities 269 Fair value of net assets acquired $ (144 ) Increase in goodwill recognized 144 Goodwill recognized as of December 31, 2017 $ 93,033

Earnings Per Common Share

Earnings Per Common Share	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Earnings Per Common Share	NOTE 3. EARNINGS PER COMMON SHARE Earnings per common share are calculated as follows: For the years ended December 31, (in thousands, except shares and per share amounts) 2017 2016 2015 Numerator for both basic and diluted earnings per common share: Net income $ 94,482 $ 86,635 $ 80,762 Denominator: Total average basic common shares outstanding 44,003,208 40,100,320 37,488,331 Effect of dilutive stock options and other stock compensation 72,085 26,756 58,796 Total diluted average common shares outstanding 44,075,293 40,127,076 37,547,127 Earnings per common share—basic $ 2.15 $ 2.16 $ 2.15 Earnings per common share—diluted 2.14 2.16 2.15 All options to purchase shares were included in the diluted shares computation for the year ended December 31, 2017 while 95,700 shares were not included in the computation for the year ended December 31, 2016 because the exercise price was greater than the average market price of the common shares and, therefore, the effect would be antidilutive. All options to purchase shares were included in the year ended December 31, 2015 computation of net income per diluted share. Market and performance-based restricted stock, totaling 24,675 shares, were not included in the computation of net income per diluted share for the year ended December 31, 2017 because the effect would be antidilutive. Market-based restricted stock, totaling 24,000 and 12,000 shares were not included in the computation of net income per diluted share for the years ended December 31, 2016 or 2015, respectively, because the effect would be antidilutive. On September 9, 2016, WesBanco issued 5,423,348 shares of common stock (109,257 of which shares were treasury stock) to complete its acquisition of YCB. These shares are included in average shares outstanding beginning on that date. For additional information relating to the YCB acquisition, refer to Note 2, “Mergers and Acquisitions.”

Securities

Securities	12 Months Ended
	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Securities	NOTE 4. SECURITIES The following table shows the amortized cost and fair values of available-for-sale and held-to-maturity securities: December 31, 2017 December 31, 2016 (in thousands) Amortized Gross Gross Estimated Amortized Gross Gross Estimated Available-for-sale U.S. Government sponsored entities and agencies $ 72,425 $ 24 $ (606 ) $ 71,843 $ 54,803 $ 3 $ (763 ) $ 54,043 Residential mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 954,115 214 (19,407 ) 934,922 953,475 884 (16,070 ) 938,289 Commercial mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 116,448 4 (1,585 ) 114,867 98,922 27 (2,139 ) 96,810 Obligations of states and political subdivisions 102,363 2,927 (460 ) 104,830 110,208 3,114 (1,659 ) 111,663 Corporate debt securities 35,234 228 (59 ) 35,403 35,292 117 (108 ) 35,301 Total debt securities $ 1,280,585 $ 3,397 $ (22,117 ) $ 1,261,865 $ 1,252,700 $ 4,145 $ (20,739 ) $ 1,236,106 Equity securities 4,223 1,390 — 5,613 4,062 1,032 (24 ) 5,070 Total available-for-sale securities $ 1,284,808 $ 4,787 $ (22,117 ) $ 1,267,478 $ 1,256,762 $ 5,177 $ (20,763 ) $ 1,241,176 Held-to-maturity U.S. Government sponsored entities and agencies $ 11,465 $ — $ (325 ) $ 11,140 $ 13,394 $ — $ (414 ) $ 12,980 Residential mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 170,025 544 (2,609 ) 167,960 215,141 1,279 (2,563 ) 213,857 Obligations of states and political subdivisions 794,655 17,364 (1,609 ) 810,410 805,019 15,652 (5,529 ) 815,142 Corporate debt securities 33,355 919 — 34,274 34,413 418 (20 ) 34,811 Total held-to-maturity securities $ 1,009,500 $ 18,827 $ (4,543 ) $ 1,023,784 $ 1,067,967 $ 17,349 $ (8,526 ) $ 1,076,790 Total $ 2,294,308 $ 23,614 $ (26,660 ) $ 2,291,262 $ 2,324,729 $ 22,526 $ (29,289 ) $ 2,317,966 Trading securities, which consist of investments in various mutual funds held in grantor trusts formed in connection with the Company’s deferred compensation plan, are recorded at fair value and totaled $7.8 million and $7.1 million, at December 31, 2017 and 2016, respectively. At December 31, 2017 and 2016, there were no holdings of any one issuer, other than U.S. government sponsored entities and its agencies, in an amount greater than 10% of WesBanco’s shareholders’ equity. The following table presents the fair value of available-for-sale and held-to-maturity securities by contractual maturity at December 31, 2017. In many instances, the issuers may have the right to call or prepay obligations without penalty prior to the contractual maturity date. December 31, 2017 (in thousands) One Year One to Five to After Ten Mortgage-backed Total Available-for-sale U.S. Government sponsored entities and agencies $ 9,938 $ 1,990 $ 16,837 $ 6,888 $ 36,190 $ 71,843 Residential mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies (1) — — — — 934,922 934,922 Commercial mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies (1) — — — — 114,867 114,867 Obligations of states and political subdivisions 3,964 18,827 39,020 43,019 — 104,830 Corporate debt securities 3,990 26,431 4,982 — — 35,403 Equity securities (2) — — — — 5,613 5,613 Total available-for-sale securities $ 17,892 $ 47,248 $ 60,839 $ 49,907 $ 1,091,592 $ 1,267,478 Held-to-maturity (3) U.S. Government sponsored entities and agencies $ — $ — $ — $ — $ 11,140 $ 11,140 Residential mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies (1) — — — — 167,960 167,960 Obligations of states and political subdivisions 4,855 106,502 406,338 292,715 — 810,410 Corporate debt securities — 7,721 26,553 — — 34,274 Total held-to-maturity securities $ 4,855 $ 114,223 $ 432,891 $ 292,715 $ 179,100 $ 1,023,784 Total $ 22,747 $ 161,471 $ 493,730 $ 342,622 $ 1,270,692 $ 2,291,262 (1) Mortgage-backed and collateralized mortgage securities, which have prepayment provisions, are not assigned to maturity categories due to fluctuations in their prepayment speeds. (2) Equity securities, which have no stated maturity, are not assigned a maturity category. (3) The held-to-maturity portfolio is carried at an amortized cost of $1.0 billion. Securities with aggregate fair values of $1.4 billion and $1.2 billion at December 31, 2017 and 2016, respectively, were pledged as security for public and trust funds, and securities sold under agreements to repurchase. Proceeds from the sale of available-for-sale securities were $7.8 million, $277.2 million and $635.6 million for the years ended December 31, 2017, 2016 and 2015, respectively. Net unrealized losses on available-for-sale securities included in accumulated other comprehensive income net of tax, as of December 31, 2017, 2016 and 2015 were $13.3 million, $9.9 million and $4.2 million, respectively. The following table presents the gross realized gains and losses on sales and calls of available-for-sale and held-to-maturity securities for the years ended December 31, 2017, 2016 and 2015, respectively. For the Years Ended (in thousands) 2017 2016 2015 Gross realized gains $ 675 $ 2,638 $ 1,029 Gross realized losses (108 ) (281 ) (81 ) Net realized gains $ 567 $ 2,357 $ 948 The following tables provide information on unrealized losses on investment securities that have been in an unrealized loss position for less than twelve months and twelve months or more as of December 31, 2017 and 2016: December 31, 2017 Less than 12 months 12 months or more Total (dollars in thousands) Fair Unrealized # of Fair Unrealized # of Fair Unrealized # of U.S. Government sponsored entities and agencies $ 24,776 $ (160 ) 4 $ 42,248 $ (771 ) 8 $ 67,024 $ (931 ) 12 Residential mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 423,794 (5,039 ) 87 637,461 (16,977 ) 193 1,061,255 (22,016 ) 280 Commercial mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 79,061 (1,089 ) 10 27,852 (496 ) 6 106,913 (1,585 ) 16 Obligations of states and political subdivisions 132,831 (852 ) 210 77,554 (1,217 ) 160 210,385 (2,069 ) 370 Corporate debt securities 4,015 (19 ) 1 1,948 (40 ) 1 5,963 (59 ) 2 Equity securities — — — — — — — — — Total temporarily impaired securities $ 664,477 $ (7,159 ) 312 $ 787,063 $ (19,501 ) 368 $ 1,451,540 $ (26,660 ) 680 December 31, 2016 Less than 12 months 12 months or more Total (dollars in thousands) Fair Unrealized # of Fair Unrealized # of Fair Unrealized # of U.S. Government sponsored entities and agencies $ 58,108 $ (1,177) 11 $ — $ — — $ 58,108 $ (1,177) 11 Residential mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 969,174 (16,436 ) 232 58,839 (2,197 ) 14 1,028,013 (18,633 ) 246 Commercial mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 88,169 (2,122 ) 14 679 (17 ) 2 88,848 (2,139 ) 16 Obligations of states and political subdivisions 364,583 (7,121 ) 604 2,047 (67 ) 3 366,630 (7,188 ) 607 Corporate debt securities 10,011 (78 ) 3 5,973 (50 ) 2 15,984 (128 ) 5 Equity securities 2,938 (24 ) 2 — — — 2,938 (24 ) 2 Total temporarily impaired securities $ 1,492,983 $ (26,958 ) 866 $ 67,538 $ (2,331 ) 21 $ 1,560,521 $ (29,289 ) 887 Unrealized losses on debt securities in the tables represent temporary fluctuations resulting from changes in market rates in relation to fixed yields. Unrealized losses in the available-for-sale portfolio are accounted for as an adjustment, net of taxes, to other comprehensive income in shareholders’ equity. WesBanco does not believe the securities presented above are impaired due to reasons of credit quality, as substantially all debt securities are rated above investment grade and all are paying principal and interest according to their contractual terms. WesBanco does not intend to sell, nor is it more likely than not that it will be required to sell, loss position securities prior to recovery of their cost, and therefore, management believes the unrealized losses detailed above are temporary and no impairment loss relating to these securities has been recognized. Securities that do not have readily determinable fair values and for which WesBanco does not exercise significant influence are carried at cost. Cost method investments consist primarily of FHLB of Pittsburgh, Cincinnati and Indianapolis stock totaling $45.9 million and $46.4 million at December 31, 2017 and 2016, respectively, and are included in other assets in the Consolidated Balance Sheets. Cost method investments are evaluated for impairment whenever events or circumstances suggest that their carrying value may not be recoverable.

Loans and the Allowance for Cre

Loans and the Allowance for Credit Losses	12 Months Ended
	Dec. 31, 2017
Receivables [Abstract]
Loans and the Allowance for Credit Losses	NOTE 5. LOANS AND THE ALLOWANCE FOR CREDIT LOSSES The recorded investment in loans is presented in the Consolidated Balance Sheets net of deferred loan fees and costs, and discounts on purchased loans. The deferred loan (costs) and fees were $(1.6) million and $0.3 million at December 31, 2017 and 2016, respectively. The unamortized discount on purchased loans from acquisitions was $21.9 million, including $10.5 million related to YCB, and $24.1 million at December 31, 2017 and 2016, respectively. December 31, December 31, (in thousands) 2017 2016 Commercial real estate: Land and construction $ 392,597 $ 496,539 Improved property 2,601,851 2,376,972 Total commercial real estate 2,994,448 2,873,511 Commercial and industrial 1,125,327 1,088,118 Residential real estate 1,353,301 1,383,390 Home equity 529,196 508,359 Consumer 339,169 396,058 Total portfolio loans 6,341,441 6,249,436 Loans held for sale 20,320 17,315 Total loans $ 6,361,761 $ 6,266,751 The following tables summarize changes in the allowance for credit losses applicable to each category of the loan portfolio: For the Year Ended December 31, 2017 (in thousands) Commercial Commercial Real Estate- Property Commercial Residential Home Consumer Deposit Total Balance at beginning of year: Allowance for loan losses $ 4,348 $ 18,628 $ 8,412 $ 4,106 $ 3,422 $ 3,998 $ 760 $ 43,674 Allowance for loan commitments 151 17 188 9 162 44 — 571 Total beginning allowance for credit losses 4,499 18,645 8,600 4,115 3,584 4,042 760 44,245 Provision for credit losses: Provision for loan losses (1,259 ) 4,386 2,733 (175 ) 2,066 1,231 1,001 9,983 Provision for loan commitments (32 ) 9 (15 ) (2 ) 50 (7 ) — 3 Total provision for credit losses (1,291 ) 4,395 2,718 (177 ) 2,116 1,224 1,001 9,986 Charge-offs (72 ) (2,381 ) (2,669 ) (1,064 ) (1,221 ) (3,989 ) (1,293 ) (12,689 ) Recoveries 100 533 938 339 230 1,823 353 4,316 Net charge-offs 28 (1,848 ) (1,731 ) (725 ) (991 ) (2,166 ) (940 ) (8,373 ) Balance at end of period: Allowance for loan losses 3,117 21,166 9,414 3,206 4,497 3,063 821 45,284 Allowance for loan commitments 119 26 173 7 212 37 — 574 Total ending allowance for credit losses $ 3,236 $ 21,192 $ 9,587 $ 3,213 $ 4,709 $ 3,100 $ 821 $ 45,858 For the Year Ended December 31, 2016 (in thousands) Commercial Commercial Commercial Residential Home Consumer Deposit Total Balance at beginning of year: Allowance for loan losses $ 4,390 $ 14,748 $ 10,002 $ 4,582 $ 2,883 $ 4,763 $ 342 $ 41,710 Allowance for loan commitments 157 26 260 7 117 46 — 613 Total beginning allowance for credit losses 4,547 14,774 10,262 4,589 3,000 4,809 342 42,323 Provision for credit losses: Provision for loan losses 26 4,223 1,160 16 662 1,356 1,077 8,520 Provision for loan commitments (6 ) (9 ) (72 ) 2 45 (2 ) — (42 ) Total provision for credit losses 20 4,214 1,088 18 707 1,354 1,077 8,478 Charge-offs (73 ) (1,886 ) (3,070 ) (937 ) (397 ) (3,606 ) (884 ) (10,853 ) Recoveries 5 1,543 320 445 274 1,485 225 4,297 Net charge-offs (68 ) (343 ) (2,750 ) (492 ) (123 ) (2,121 ) (659 ) (6,556 ) Balance at end of period: Allowance for loan losses 4,348 18,628 8,412 4,106 3,422 3,998 760 43,674 Allowance for loan commitments 151 17 188 9 162 44 — 571 Total ending allowance for credit losses $ 4,499 $ 18,645 $ 8,600 $ 4,115 $ 3,584 $ 4,042 $ 760 $ 44,245 For the Year Ended December 31, 2015 (in thousands) Commercial Commercial Commercial Residential Home Consumer Deposit Total Balance at beginning of year: Allowance for loan losses $ 5,654 $ 17,573 $ 9,063 $ 5,382 $ 2,329 $ 4,078 $ 575 $ 44,654 Allowance for loan commitments 194 10 112 9 90 40 — 455 Total beginning allowance for credit losses 5,848 17,583 9,175 5,391 2,419 4,118 575 45,109 Provision for credit losses: Provision for loan losses (1,265 ) 1,250 3,289 399 1,794 2,337 391 8,195 Provision for loan commitments (37 ) 16 148 (2 ) 27 6 — 158 Total provision for credit losses (1,302 ) 1,266 3,437 397 1,821 2,343 391 8,353 Charge-offs — (4,915 ) (2,785 ) (1,803 ) (1,502 ) (2,892 ) (846 ) (14,743 ) Recoveries 1 840 435 604 262 1,240 222 3,604 Net charge-offs 1 (4,075 ) (2,350 ) (1,199 ) (1,240 ) (1,652 ) (624 ) (11,139 ) Balance at end of period: Allowance for loan losses 4,390 14,748 10,002 4,582 2,883 4,763 342 41,710 Allowance for loan commitments 157 26 260 7 117 46 — 613 Total ending allowance for credit losses $ 4,547 $ 14,774 $ 10,262 $ 4,589 $ 3,000 $ 4,809 $ 342 $ 42,323 The following tables present the allowance for credit losses and recorded investments in loans by category: Allowance for Credit Losses and Recorded Investment in Loans (in thousands) Commercial Commercial Commercial Residential Home Consumer Deposit Total December 31, 2017 Allowance for credit losses: Allowance for loans individually evaluated for impairment $ — $ 388 $ — $ — $ — $ — $ — $ 388 Allowance for loans collectively evaluated for impairment 3,117 20,778 9,414 3,206 4,497 3,063 821 44,896 Allowance for loan commitments 119 26 173 7 212 37 — 574 Total allowance for credit losses $ 3,236 $ 21,192 $ 9,587 $ 3,213 $ 4,709 $ 3,100 $ 821 $ 45,858 Portfolio loans: Individually evaluated for impairment (1) $ — $ 3,344 $ — $ — $ — $ — $ — $ 3,344 Collectively evaluated for impairment 391,140 2,593,393 1,124,544 1,352,587 529,196 339,163 — 6,330,023 Acquired with deteriorated credit quality 1,457 5,114 783 714 — 6 — 8,074 Total portfolio loans $ 392,597 $ 2,601,851 $ 1,125,327 $ 1,353,301 $ 529,196 $ 339,169 $ — $ 6,341,441 December 31, 2016 Allowance for credit losses: Allowance for loans individually evaluated for impairment $ — $ 470 $ 407 $ — $ — $ — $ — $ 877 Allowance for loans collectively evaluated for impairment 4,348 18,158 8,005 4,106 3,422 3,998 760 42,797 Allowance for loan commitments 151 17 188 9 162 44 — 571 Total allowance for credit losses $ 4,499 $ 18,645 $ 8,600 $ 4,115 $ 3,584 $ 4,042 $ 760 $ 44,245 Portfolio loans: Individually evaluated for impairment (1) $ — $ 3,012 $ 1,270 $ — $ — $ — $ — $ 4,282 Collectively evaluated for impairment 494,928 2,364,067 1,086,445 1,382,447 508,359 396,049 — 6,232,295 Acquired with deteriorated credit quality 1,611 9,893 403 943 — 9 — 12,859 Total portfolio loans $ 496,539 $ 2,376,972 $ 1,088,118 $ 1,383,390 $ 508,359 $ 396,058 $ — $ 6,249,436 (1) Commercial loans greater than $1 million that are reported as non-accrual or as a TDR are individually evaluated for impairment. WesBanco maintains an internal loan grading system to reflect the credit quality of commercial loans. Commercial loan risk grades are determined based on an evaluation of the relevant characteristics of each loan, assigned at the inception of each loan and adjusted thereafter at any time to reflect changes in the risk profile throughout the life of each loan. The primary factors used to determine the risk grade are the reliability and sustainability of the primary source of repayment and overall financial strength of the borrower. This includes an analysis of cash flow available to repay debt, profitability, liquidity, leverage, and overall financial trends. Other factors include management, industry or property type risks, an assessment of secondary sources of repayment such as collateral or guarantees, other terms and conditions of the loan that may increase or reduce its risk, and economic conditions and other external factors that may influence repayment capacity and financial condition. Commercial real estate—land and construction consists of loans to finance investments in vacant land, land development, construction of residential housing, and construction of commercial buildings. Commercial real estate—improved property consists of loans for the purchase or refinance of all types of improved owner-occupied and investment properties. Factors that are considered in assigning the risk grade vary depending on the type of property financed. The risk grade assigned to construction and development loans is based on the overall viability of the project, the experience and financial capacity of the developer or builder to successfully complete the project, project specific and market absorption rates and comparable property values, and the amount of pre-sales for residential housing construction or pre-leases for commercial investment property. The risk grade assigned to commercial investment property loans is based primarily on the adequacy of net rental income generated by the property to service the debt, the type, quality, industry and mix of tenants, and the terms of leases, but also considers the overall financial capacity of the investors and their experience in owning and managing investment property. The risk grade assigned to owner-occupied commercial real estate and commercial and industrial loans is based primarily on historical and projected earnings, the adequacy of operating cash flow to service all of the business’ debt, and the capital resources, liquidity and leverage of the business, but also considers the industry in which the business operates, the business’ specific competitive advantages or disadvantages, the quality and experience of management, and external influences on the business such as economic conditions. Commercial and industrial loans consist of revolving lines of credit to finance accounts receivable, inventory and other general business purposes; term loans to finance fixed assets other than real estate, and letters of credit to support trade, insurance or governmental requirements for a variety of businesses. Most C&I borrowers are privately-held companies with annual sales up to $100 million. Factors that are considered for commercial and industrial loans include the type, quality and marketability of non-real estate collateral and whether the structure of the loan increases or reduces its risk. The type, age, condition, location and any environmental risks associated with a property are also considered for all types of commercial real estate. The overall financial condition and repayment capacity of any guarantors is also evaluated to determine the extent to which they mitigate other risks of the loan. The following paragraphs provide descriptions of risk grades that are applicable to commercial real estate and commercial and industrial loans. Pass loans are those that exhibit a history of positive financial results that are at least comparable to the average for their industry or type of real estate. The primary source of repayment is acceptable and these loans are expected to perform satisfactorily during most economic cycles. Pass loans typically have no significant external factors that are expected to adversely affect these borrowers more than others in the same industry or property type. Any minor unfavorable characteristics of these loans are outweighed or mitigated by other positive factors including but not limited to adequate secondary or tertiary sources of repayment. Criticized or compromised loans are currently protected but have weaknesses, which, if not corrected, may be inadequately protected at some future date. These loans represent an unwarranted credit risk and would generally not be extended in the normal course of lending. Specific issues which may warrant this grade include declining financial results, increased reliance on secondary sources of repayment or guarantor support and adverse external influences that may negatively impact the business or property. Substandard and doubtful loans are equivalent to the classifications used by banking regulators. Substandard loans are inadequately protected by the current repayment capacity and equity of the borrower or collateral pledged, if any. Substandard loans have one or more well-defined weaknesses that jeopardize their repayment or collection in full. These loans may or may not be reported as non-accrual. Doubtful loans have all the weaknesses inherent to a substandard loan with the added characteristic that full repayment is highly questionable or improbable on the basis of currently existing facts, conditions and collateral values. However, recognition of loss may be deferred if there are reasonably specific pending factors that will reduce the risk if they occur. The following tables summarize commercial loans by their assigned risk grade: Commerical Loans by Internally Assigned Risk Grade (in thousands) Commercial Commercial Commercial Total As of December 31, 2017 Pass $ 386,753 $ 2,548,805 $ 1,110,267 $ 4,045,825 Criticized—compromised 2,984 25,673 7,435 36,092 Classified—substandard 2,860 27,373 7,625 37,858 Classified—doubtful — — — — Total $ 392,597 $ 2,601,851 $ 1,125,327 $ 4,119,775 As of December 31, 2016 Pass $ 489,380 $ 2,324,755 $ 1,072,751 $ 3,886,886 Criticized—compromised 4,405 15,295 5,078 24,778 Classified—substandard 2,754 36,922 10,289 49,965 Classified—doubtful — — — — Total $ 496,539 $ 2,376,972 $ 1,088,118 $ 3,961,629 Residential real estate, home equity and consumer loans are not assigned internal risk grades other than as required by regulatory guidelines that are based primarily on the age of past due loans. WesBanco primarily evaluates the credit quality of residential real estate, home equity and consumer loans based on repayment performance and historical loss rates. The aggregate amount of residential real estate, home equity and consumer loans classified as substandard in accordance with regulatory guidelines were $22.8 million at December 31, 2017 and $20.6 million at December 31, 2016, of which $2.5 and $3.4 million were accruing, for each period, respectively. The aggregate amount of residential real estate, home equity and consumer loans classified as substandard are not included in the tables above. Acquired YCB Loans Acquired ESB Loans The following table provides changes in accretable yield for all loans acquired with deteriorated credit quality: For the Years Ended (in thousands) December 31, December 31, Balance at beginning of period $ 1,717 $ 1,206 Acquisitions — 837 Reduction due to change in projected cash flows — (484 ) Reclass from non-accretable difference 1,719 1,065 Transfers (216 ) (328 ) Accretion (1,496 ) (579 ) Balance at end of period $ 1,724 $ 1,717 The following tables summarize the age analysis of all categories of loans. Age Analysis of Loans (in thousands) Current 30-59 Days 60-89 Days 90 Days Total Total 90 Days As of December 31, 2017 Commercial real estate: Land and construction $ 392,189 $ — $ 172 $ 236 $ 408 $ 392,597 $ — Improved property 2,589,704 374 1,200 10,573 12,147 2,601,851 243 Total commercial real estate 2,981,893 374 1,372 10,809 12,555 2,994,448 243 Commercial and industrial 1,121,957 572 196 2,602 3,370 1,125,327 20 Residential real estate 1,338,240 4,487 2,376 8,198 15,061 1,353,301 1,113 Home equity 522,584 2,135 683 3,794 6,612 529,196 742 Consumer 334,723 2,466 842 1,138 4,446 339,169 608 Total portfolio loans 6,299,397 10,034 5,469 26,541 42,044 6,341,441 2,726 Loans held for sale 20,320 — — — — 20,320 — Total loans $ 6,319,717 $ 10,034 $ 5,469 $ 26,541 $ 42,044 $ 6,361,761 $ 2,726 Impaired loans included above are as follows: Non-accrual loans $ 9,195 $ 1,782 $ 2,033 $ 23,815 27,630 $ 36,825 TDRs accruing interest (1) 6,055 348 168 — 516 6,571 Total impaired $ 15,250 $ 2,130 $ 2,201 $ 23,815 $ 28,146 $ 43,396 As of December 31, 2016 Commercial real estate: Land and construction $ 496,245 $ — $ — $ 294 $ 294 $ 496,539 $ — Improved property 2,367,790 1,154 363 7,665 9,182 2,376,972 318 Total commercial real estate 2,864,035 1,154 363 7,959 9,476 2,873,511 318 Commercial and industrial 1,082,390 2,508 1,011 2,209 5,728 1,088,118 229 Residential real estate 1,365,956 6,701 1,043 9,690 17,434 1,383,390 1,922 Home equity 502,087 2,358 862 3,052 6,272 508,359 626 Consumer 390,354 3,674 1,149 881 5,704 396,058 644 Total portfolio loans 6,204,822 16,395 4,428 23,791 44,614 6,249,436 3,739 Loans held for sale 17,315 — — — — 17,315 — Total loans $ 6,222,137 $ 16,395 $ 4,428 $ 23,791 $ 44,614 $ 6,266,751 $ 3,739 Impaired loans included above are as follows: Non-accrual loans $ 7,570 $ 3,479 $ 923 $ 19,812 24,214 $ 31,784 TDRs accruing interest (1) 7,014 342 50 240 632 7,646 Total impaired $ 14,584 $ 3,821 $ 973 $ 20,052 $ 24,846 $ 39,430 (1) Loans 90 days or more past due and accruing interest exclude TDRs 90 days or more past due and accruing interest. The following tables summarize impaired loans: Impaired Loans December 31, 2017 December 31, 2016 (in thousands) Unpaid Recorded Related Unpaid Recorded Related With no related specific allowance recorded: Commercial real estate: Land and construction $ 412 $ 239 $ — $ 1,212 $ 766 $ — Improved property 18,229 12,863 — 9,826 8,141 — Commercial and industrial 3,745 3,086 — 4,456 3,181 — Residential real estate 20,821 18,982 — 20,152 18,305 — Home equity 5,833 5,169 — 4,589 4,011 — Consumer 1,084 952 — 884 744 — Total impaired loans without a specific allowance 50,124 41,291 — 41,119 35,148 — With a specific allowance recorded: Commercial real estate: Land and construction — — — — — — Improved property 2,105 2,105 388 3,012 3,012 470 Commercial and industrial — — — 4,875 1,270 407 Total impaired loans with a specific allowance 2,105 2,105 388 7,887 4,282 877 Total impaired loans $ 52,229 $ 43,396 $ 388 $ 49,006 $ 39,430 $ 877 (1) The difference between the unpaid principal balance and the recorded investment generally reflects amounts that have been previously charged-off and fair market value adjustments on acquired impaired loans. Impaired Loans For the Year Ended For the Year Ended For the Year Ended (in thousands) Average Interest Average Interest Average Interest With no related specific allowance recorded: Commercial real estate: Land and construction $ 460 $ — $ 993 $ — $ 2,156 $ 41 Improved property 10,790 436 9,128 115 17,192 437 Commercial and industrial 3,577 8 3,188 9 2,979 170 Residential real estate 17,991 252 17,021 308 17,876 862 Home equity 4,599 19 3,502 20 2,924 90 Consumer 787 7 909 8 1,199 105 Total impaired loans without a specific allowance 38,204 722 34,741 460 44,326 1,705 With a specific allowance recorded: Commercial real estate: Land and construction — — — — — — Improved property 4,446 — 3,012 — 5,896 — Commercial and industrial 254 — 3,214 — 3,579 292 Total impaired loans with a specific allowance 4,700 — 6,226 — 9,475 292 Total impaired loans $ 42,904 $ 722 $ 40,967 $ 460 $ 53,801 $ 1,997 The following tables present the recorded investment in non-accrual loans and TDRs: Non-accrual Loans (1) (in thousands) December 31, December 31, Commercial real estate: Land and construction $ 239 $ 766 Improved property 13,318 9,535 Total commercial real estate 13,557 10,301 Commercial and industrial 2,958 4,299 Residential real estate 14,661 12,994 Home equity 4,762 3,538 Consumer 887 652 Total $ 36,825 $ 31,784 (1) At December 31, 2017, there were three borrowers with loans greater than $1.0 million totaling $6.8 million, as compared to two borrowers with loans greater than $1.0 million totaling $4.3 million at December 31, 2016. Total non-accrual loans include loans that are also restructured. Such loans are also set forth in the following table as non-accrual TDRs. TDRs December 31, 2017 December 31, 2016 (in thousands) Accruing Non-Accrual Total Accruing Non-Accrual Total Commercial real estate: Land and construction $ — $ 3 $ 3 $ — $ 8 $ 8 Improved property 1,650 428 2,078 1,618 688 2,306 Total commercial real estate 1,650 431 2,081 1,618 696 2,314 Commercial and industrial 128 97 225 152 151 303 Residential real estate 4,321 1,880 6,201 5,311 2,212 7,523 Home equity 407 337 744 473 297 770 Consumer 65 120 185 92 190 282 Total $ 6,571 $ 2,865 $ 9,436 $ 7,646 $ 3,546 $ 11,192 As of December 31, 2017 and December 31, 2016, there were no TDRs greater than $1.0 million. The concessions granted in the majority of loans reported as accruing and non-accrual TDRs are extensions of the maturity date or the amortization period, reductions in the interest rate below the prevailing market rate for loans with comparable characteristics, and/or permitting interest-only payments for longer than three months. WesBanco had unfunded commitments to debtors whose loans were classified as impaired of $0.1 million and $0 as of December 31, 2017 and 2016, respectively. The following table presents details related to loans identified as TDRs during the years ended December 31, 2017 and 2016: For the Year Ended December 31, 2017 For the Year Ended December 31, 2016 (dollars in thousands) Number of Pre- Post- Number of Pre- Post- Commercial real estate: Land and construction — $ — $ — — $ — $ — Improved property 2 345 331 — — — Total commercial real estate 2 345 331 — — — Commercial and industrial 1 64 58 2 125 120 Residential real estate 3 144 137 4 178 166 Home equity 2 68 61 1 44 40 Consumer 5 43 30 14 98 74 Total 13 $ 664 $ 617 21 $ 445 $ 400 (1) Excludes loans that were either paid off or charged-off by period end. The pre-modification balance represents the balance outstanding at the beginning of the period. The post-modification balance represents the outstanding balance at period end. The following table summarizes TDRs which defaulted (defined as past due 90 days) during the years ended December 31, 2017 and 2016 that were restructured within the last twelve months prior to December 31, 2017 and 2016: Defaulted TDRs (1) For the Year Ended Defaulted TDRs (1) For the Year Ended (dollars in thousands) Number of Recorded Number of Recorded Commercial real estate: Land and construction — $ — — $ — Improved property — — — — Total commercial real estate — — — — Commercial and industrial — — — — Residential real estate 2 128 — — Home equity 1 7 — — Consumer — — 1 16 Total 3 $ 135 1 $ 16 (1) Excludes loans that were either charged-off or cured by period end. The recorded investment is as of December 31, 2017 and 2016. TDRs that default are placed on non-accrual status unless they are both well-secured and in the process of collection. The loans in the table above were not accruing interest. The following table summarizes the recognition of interest income on impaired loans: For the years ended December 31, (in thousands) 2017 2016 2015 Average impaired loans $ 42,904 $ 40,967 $ 53,801 Amount of contractual interest income on impaired loans 3,089 2,747 3,061 Amount of interest income recognized on impaired loans 722 460 1,997 The following table summarizes other real estate owned and repossessed assets included in other assets: December 31, (in thousands) 2017 2016 Other real estate owned $ 5,195 $ 8,206 Repossessed assets 102 140 Total other real estate owned and repossessed assets $ 5,297 $ 8,346 At December 31, 2017, other real estate owned included $0.4 million from the YCB acquisition. Residential real estate included in other real estate owned at December 31, 2017 and December 31, 2016 was $1.5 million and $1.6 million, respectively. At December 31, 2017, formal foreclosure proceedings were in process on residential real estate loans totaling $3.5 million.

Premises and Equipment

Premises and Equipment	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Premises and Equipment	NOTE 6. PREMISES AND EQUIPMENT Premises and equipment include: December 31, (in thousands) 2017 2016 Land and improvements $ 41,209 $ 43,059 Buildings and improvements 141,960 136,546 Furniture and equipment 75,816 72,050 Total cost 258,985 251,655 Accumulated depreciation and amortization (128,263 ) (118,358 ) Total premises and equipment, net $ 130,722 $ 133,297 Depreciation and amortization expense of premises and equipment charged to operations for the years ended December 31, 2017, 2016 and 2015 was $10.4 million, $9.2 million and $8.1 million, respectively. WesBanco leases certain premises and equipment under non-cancellable operating leases. Certain leases contain renewal options and rent escalation clauses calling for rent increases over the term of the lease. All leases which contain a rent escalation clause are accounted for on a straight-line basis. Rent expense under leases was $4.2 million, $3.5 million and $3.1 million for the years ended December 31, 2017, 2016 and 2015, respectively. Future minimum lease payments under non-cancellable leases with initial or remaining lease terms in excess of one year at December 31, 2017 are as follows ( in thousands Year Amount 2018 $ 4,240 2019 3,713 2020 3,548 2021 3,089 2022 2,294 2023 and thereafter 13,690 Total $ 30,574

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	NOTE 7. GOODWILL AND OTHER INTANGIBLE ASSETS WesBanco’s Consolidated Balance Sheets include goodwill of $573.9 million and $573.8 million at December 31, 2017 and 2016, respectively all of which relates to the Community Banking segment. WesBanco’s other intangible assets of $15.3 million and $19.4 million at December 31, 2017 and 2016, respectively, primarily consist of core deposit and other customer list intangibles which have finite lives and are amortized using straight line and accelerated methods. WesBanco recognized $93.0 million in goodwill and $12.0 million in core deposit intangibles in connection with the YCB acquisition. Other intangible assets are being amortized over estimated useful lives ranging from ten to sixteen years. Amortization of core deposit and customer list intangible assets totaled $4.1 million, $2.9 million and $2.4 million for the years ended December 31, 2017, 2016 and 2015, respectively. WesBanco completed its annual goodwill impairment evaluation as of November 30, 2017 and determined that goodwill was not impaired as of December 31, 2017 as there were no significant changes in market conditions, consolidated operating results, or forecasted future results from November 30, 2017. Additionally, there were no events or changes in circumstances indicating impairment of intangible assets as of December 31, 2017. The following table shows WesBanco’s capitalized other intangible assets and related accumulated amortization: December 31, (in thousands) 2017 2016 Other intangible assets: Gross carrying amount $ 37,725 $ 37,725 Accumulated amortization (22,407 ) (18,341 ) Net carrying amount of other intangible assets $ 15,318 $ 19,384 The following table shows the amortization on WesBanco’s other intangible assets for each of the next five years ( in thousands Year Amount 2018 $ 3,543 2019 3,037 2020 2,564 2021 2,122 2022 1,701 As part of the YCB and ESB acquisitions, WesBanco entered into non-compete agreements with former YCB and ESB executives with terms ranging from one to four years. The non-compete agreements are recognized in other assets on the balance sheet with the amortization expense recognized in amortization of intangible assets on the income statement. Amortization expense of non-compete agreements totaled $0.9 million and $0.7 million in 2017 and 2016, respectively and is expected to be $0.6 million, $0.2 million and $0 million in the next three years, respectively.

Investments in Limited Partners

Investments in Limited Partnerships	12 Months Ended
	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Investments in Limited Partnerships	NOTE 8. INVESTMENTS IN LIMITED PARTNERSHIPS WesBanco is a limited partner in several tax-advantaged limited partnerships whose purpose is to invest in approved low-income housing investment tax credit projects. These investments are accounted for using the equity method of accounting and are included in other assets in the Consolidated Balance Sheets. The limited partnerships are considered to be VIEs as they generally do not have equity investors with voting rights or have equity investors that do not provide sufficient financial resources to support their activities. The VIEs have not been consolidated because WesBanco is not considered the primary beneficiary. All of WesBanco’s investments in limited partnerships are privately held, and their market values are not readily available. At December 31, 2017 and 2016, WesBanco had $15.6 million and $14.3 million, respectively, invested in these partnerships. WesBanco also recognizes the unconditional unfunded equity commitments of $10.7 million and $8.2 million at December 31, 2017 and 2016, respectively, in other liabilities. For the years ended December 31, 2016 and 2015, WesBanco included in operations under the equity method of accounting its share of the partnerships’ losses and impairment of $0.9 million, and $0.6 million, respectively. WesBanco made an accounting policy election to adopt ASU No. 2014-01 in the first quarter of 2017. With the adoption of this pronouncement, WesBanco now classifies the amortization of the investment as a component of income tax expense (benefit) and is proportionally amortized over the tax credit period. The amount for the year ended December 31, 2017 was $1.5 million, which is included in income tax expense within WesBanco’s Consolidated Financial Statements. Tax benefits attributed to these partnerships include low-income housing and historic tax credits which totaled $1.6 million, $0.8 million and $0.5 million for the years ended December 31, 2017, 2016 and 2015, respectively. WesBanco is also a limited partner in seven other limited partnerships which provide seed money and capital to startup companies, and financing to low-income housing projects. At December 31, 2017 and 2016, WesBanco had $5.4 million and $5.2 million, respectively, invested in these partnerships, which are recorded in other assets using the equity method. WesBanco included in operations under the equity method of accounting its share of the partnerships’ net income of $47 thousand, net income of $19 thousand and net loss of $1 thousand for the years ended December 31, 2017, 2016 and 2015, respectively.

Certificates of Deposit

Certificates of Deposit	12 Months Ended
	Dec. 31, 2017
Banking and Thrift [Abstract]
Certificates of Deposit	NOTE 9. CERTIFICATES OF DEPOSIT Certificates of deposit in denominations of $100 thousand or more were $581.6 million and $681.5 million as of December 31, 2017 and 2016, respectively. Interest expense on certificates of deposit of $100 thousand or more was $4.4 million, $5.0 million and $4.9 million for the years ended December 31, 2017, 2016 and 2015, respectively. At December 31, 2017, the scheduled maturities of total certificates of deposit are as follows (in thousands) Year Amount 2018 $ 736,435 2019 218,392 2020 154,186 2021 83,079 2022 49,564 2023 and thereafter 35,401 Total $ 1,277,057

FHLB and Other Short-Term Borro

FHLB and Other Short-Term Borrowings	12 Months Ended
	Dec. 31, 2017
Text Block [Abstract]
FHLB and Other Short-Term Borrowings	NOTE 10. FHLB AND OTHER SHORT-TERM BORROWINGS WesBanco is a member of the FHLB system. WesBanco’s FHLB borrowings, which consist of borrowings from both the FHLB of Pittsburgh and the FHLB of Cincinnati, are secured by a blanket lien by the FHLB on certain residential mortgages and other loan types or securities with a market value in excess of the outstanding balances of the borrowings. At December 31, 2017 and 2016, WesBanco had FHLB borrowings of $948.2 million and $968.9 million, respectively, with a remaining weighted-average interest rate of 1.57% and 1.19%, respectively. The terms of the security agreement with the FHLB include a specific assignment of collateral that requires the maintenance of qualifying mortgage and other types of loans as pledged collateral with unpaid principal amounts in excess of the FHLB advances, when discounted at certain pre-established percentages of the loans’ unpaid principal balances. FHLB stock owned by WesBanco totaling $45.9 million and $46.4 million at December 31, 2017 and 2016, respectively, is also pledged as collateral on these advances. The remaining maximum borrowing capacity by WesBanco with the FHLB at December 31, 2017 and 2016 was estimated to be approximately $1.8 billion and $1.7 billion, respectively. The following table presents the aggregate annual maturities and weighted-average interest rates of FHLB borrowings at December 31, 2017 based on their contractual maturity dates and interest rates (dollars in thousands) Year Scheduled Weighted 2018 $ 540,770 1.40 % 2019 334,104 1.78 % 2020 71,064 1.96 % 2021 294 5.22 % 2022 — 0.00 % 2023 and thereafter 1,971 1.42 % Total $ 948,203 1.57 % Other short-term borrowings of $184.8 million and $199.4 million at December 31, 2017 and 2016, respectively, consist of securities sold under agreements to repurchase, federal funds purchased, and outstanding borrowings on a revolving line of credit. At December 31, 2017 and 2016, securities sold under agreements to repurchase were $159.8 million and $141.4 million, respectively, with a weighted average interest rate during the year of 0.67% and 0.38%, respectively. There were $25 million and $58.0 million, respectively, in outstanding balances of fed funds purchased at December 31, 2017 and 2016 with interest rates of 1.60% and 0.85%, respectively. In September 2017, WesBanco renewed a revolving line of credit, which is a senior obligation of the parent company with another financial institution. This line of credit, which accrues interest at an adjusted LIBOR rate, provides for aggregate unsecured borrowings of up to $25.0 million. There were no outstanding balances as of December 31, 2017 or 2016.

Subordinated Debt and Junior Su

Subordinated Debt and Junior Subordinated Debt	12 Months Ended
	Dec. 31, 2017
Text Block [Abstract]
Subordinated Debt and Junior Subordinated Debt	NOTE 11. SUBORDINATED DEBT AND JUNIOR SUBORDINATED DEBT WesBanco had $25.8 million of subordinated debt outstanding at December 31, 2017 that was issued by the former YCB, acquired by WesBanco in 2016. These notes have a fixed rate of 6.25%, mature on December 15, 2025, and are callable on December 15, 2020. The interest rate will become a variable rate equal to 3-month LIBOR plus 4.59% on the call date. The subordinated debt is considered Tier 2 regulatory capital for WesBanco and WesBanco Bank. The Trusts, consisting of WesBanco Capital Trust II, WesBanco Capital Statutory Trust III, WesBanco Capital Trusts IV, V and VI, Oak Hill Capital Trusts 2, 3 and 4, Community Bank Shares Statutory Trusts I and II, and First Federal Statutory Trusts II and III are all wholly-owned trust subsidiaries of WesBanco formed for the purpose of issuing Trust Preferred Securities (“Trust Preferred Securities”) into a pool of other financial services entity trust preferred securities, and lending the proceeds to WesBanco. The Trust Preferred Securities were issued and sold in private placement offerings. The proceeds from the sale of the securities and the issuance of common stock by the Trusts were invested in Junior Subordinated Deferrable Interest Debentures (“Junior Subordinated Debt”) issued by WesBanco, the former Oak Hill Financial, Inc., acquired by WesBanco in 2007, and the former YCB, acquired by WesBanco in 2016, which are the sole assets of the Trusts. The Trusts pay dividends on the Trust Preferred Securities at the same rate as the distributions paid by WesBanco on the Junior Subordinated Debt held by the Trusts. The Trusts provide WesBanco with the option to defer payment of interest on the Junior Subordinated Debt for an aggregate of 20 consecutive quarterly periods. Should any of these options be utilized, WesBanco may not declare or pay dividends on its common stock during any such period. Undertakings made by WesBanco with respect to the Trust Preferred Securities for the Trusts constitute a full and unconditional guarantee by WesBanco of the obligations of these Trust Preferred Securities. WesBanco organized Trusts II and III in June 2003, Trusts IV and V in June 2004 and Trust VI in March 2005. The Oak Hill Trusts 2 and 3 were organized in 2004 and Trust 4 was organized in 2005. The Community Bank Trust I was organized in 2004, and Trust II was organized in 2006. The First Federal Trust II was organized in 2007, and Trust III was organized in 2008. The Junior Subordinated Debt is presented as a separate category of long-term debt on the Consolidated Balance Sheets. For regulatory purposes, the Federal Reserve Board has allowed bank holding companies to include trust preferred securities in Tier 1 capital up to a certain limit. Provisions in the Dodd-Frank Act require the Federal Reserve Board to generally exclude trust preferred securities from Tier 1 capital, but a grandfather provision will permit bank holding companies with consolidated assets of less than $15 billion, such as WesBanco, to continue counting existing trust preferred securities as Tier 1 capital until they mature. All of the Trust Preferred Securities qualified under the current rules as Tier 1 instruments at December 31, 2017, but no such securities issued in the future will count as Tier 1 capital. The Trust Preferred Securities provide the issuer with a unique capital instrument that has a tax deductible interest feature not normally associated with the equity of a corporation. The following table shows WesBanco’s trust subsidiaries with outstanding Trust Preferred Securities as of December 31, 2017: (in thousands) Trust Common Junior Stated Optional WesBanco Capital Trust II (1) $ 13,000 $ 410 $ 13,410 6/30/2033 6/30/2008 WesBanco Capital Statutory Trust III (2) 17,000 526 17,526 6/26/2033 6/26/2008 WesBanco Capital Trust IV (3) 20,000 619 20,619 6/17/2034 6/17/2009 WesBanco Capital Trust V (3) 20,000 619 20,619 6/17/2034 6/17/2009 WesBanco Capital Trust VI (4) 15,000 464 15,464 3/17/2035 3/17/2010 Oak Hill Capital Trust 2 (5) 5,000 155 5,155 10/18/2034 10/18/2009 Oak Hill Capital Trust 3 (6) 8,000 248 8,248 10/18/2034 10/18/2009 Oak Hill Capital Trust 4 (7) 5,000 155 5,155 6/30/2035 6/30/2015 Community Bank Shares Statutory Trust I (3) 6,252 217 6,469 6/17/2034 6/17/2014 Community Bank Shares Statutory Trust II (8) 8,476 310 8,786 6/15/2036 6/15/2016 First Federal Statutory Trust II (9) 8,419 310 8,729 3/22/2037 3/15/2017 First Federal Statutory Trust III (10) 8,144 240 8,384 6/24/2038 6/24/2018 Total $ 134,291 $ 4,273 $ 138,564 (1) Variable rate based on the three-month LIBOR plus 3.15% with a current rate of 4.84% through March 30, 2018, adjustable quarterly. (2) Variable rate based on the three-month LIBOR plus 3.10% with a current rate of 4.77% through March 26, 2018, adjustable quarterly. (3) Variable rate based on the three-month LIBOR plus 2.65% with a current rate of 4.25% through March 17, 2018, adjustable quarterly. (4) Variable rate based on the three-month LIBOR plus 1.77% with a current rate of 3.37% through March 17, 2018, adjustable quarterly. (5) Variable rate based on the three-month LIBOR plus 2.40% with a current rate of 3.75% through January 18, 2018, adjustable quarterly. (6) Variable rate based on the three-month LIBOR plus 2.30% with a current rate of 3.65% through January 18, 2018, adjustable quarterly. (7) Variable rate based on the three-month LIBOR plus 1.60% with a current rate of 3.29% through March 30, 2018, adjustable quarterly. (8) Variable rate based on the three-month LIBOR plus 1.70% with a current rate of 3.29% through March 15, 2018, adjustable quarterly. (9) Variable rate based on the three-month LIBOR plus 1.60% with a current rate of 3.19% through March 15, 2018, adjustable quarterly. (10) Fixed rate of 8.00% through maturity, callable June 24, 2018 and thereafter at par.

Derivatives and Hedging Activit

Derivatives and Hedging Activities	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives and Hedging Activities	NOTE 12. DERIVATIVES AND HEDGING ACTIVITIES Risk Management Objective of Using Derivatives WesBanco is exposed to certain risks arising from both its business operations and economic conditions. WesBanco principally manages its exposures to a wide variety of business and operational risks through management of its core business activities. WesBanco manages economic risks, including interest rate, liquidity, and credit risk, primarily by managing the amount, sources, and duration of its assets and liabilities. WesBanco’s existing interest rate derivatives result from a service provided to certain qualifying customers and, therefore, are not used to manage interest rate risk in WesBanco’s assets or liabilities. WesBanco manages a matched book with respect to its derivative instruments in order to minimize its net risk exposure resulting from such transactions. A matched book is when the Bank’s assets and liabilities are equally distributed but also have similar maturities. Loan Swaps WesBanco executes interest rate swaps with commercial banking customers to facilitate their respective risk management strategies. Those interest rate swaps are simultaneously hedged by offsetting interest rate swaps that WesBanco executes with a third party, such that WesBanco minimizes its net risk exposure resulting from such transactions. As the interest rate swaps associated with this program do not meet the strict hedge accounting requirements of FASB ASC 815, changes in the fair value of both the customer swaps and the offsetting third-party swaps are recognized directly in earnings. As of December 31, 2017 and 2016, WesBanco had 39 and 24, respectively, interest rate swaps with an aggregate notional amount of $298.2 and $206.9 million, respectively, related to this program. During the years ended December 31, 2017, 2016, and 2015, WesBanco recognized (net loss) net gains of $(0.4) million, $0.5 million and $3 thousand, respectively, related to the changes in fair value of these swaps. Additionally, WesBanco recognized $2.3 million, $2.5 million and $0.2 million income for the related swap fees for the years ended December 31, 2017, 2016, and 2015, respectively. Mortgage Loans Held for Sale and Loan Commitments Certain residential mortgage loans are originated for sale in the secondary mortgage loan market. These loans are classified as held for sale and carried at fair value as WesBanco has elected the fair value option. Fair value is determined based on rates obtained from the secondary market for loans with similar characteristics. WesBanco sells loans to the secondary market on a mandatory or best efforts basis. The loans sold on a mandatory basis are not committed to an investor until the loan is closed with the borrower. WesBanco enters into forward TBA contracts to manage the interest rate risk between the loan commitment and the closing of the loan. The loans sold on a best efforts basis are committed to an investor simultaneous to the interest rate commitment with the borrower. Fair Values of Derivative Instruments on the Balance Sheet All derivatives are carried on the consolidated balance sheet at fair value. Derivative assets are classified in the consolidated balance sheet under other assets, and derivative liabilities are classified in the consolidated balance sheet under other liabilities. Changes in fair value are recognized in earnings. None of WesBanco’s derivatives are designated in qualifying hedging relationships under FASB ASC 815. The table below presents the fair value of WesBanco’s derivative financial instruments as well as their classification on the Balance Sheet as of December 31, 2017 and December 31, 2016: December 31, 2017 December 31, 2016 (in thousands) Notional or Asset Liability Notional or Asset Liability Derivatives Loan Swaps: Interest rate swaps $ 298,223 $ 7,351 $ 7,345 $ 206,923 $ 5,596 $ 5,199 Other contracts: Interest rate loan commitments 20,319 49 — 19,453 — 123 Best efforts forward delivery commitments 2,905 — 6 19,453 79 — Forward TBA contracts 31,750 — 23 — — — Total derivatives $ 7,400 $ 7,374 $ 5,675 $ 5,322 Effect of Derivative Instruments on the Income Statement The table below presents the change in the fair value of the Company’s derivative financial instruments reflected within the other non-interest income line item of the consolidated income statement for the years ended December 31, 2017, 2016 and 2015, respectively. For the Years Ended (in thousands) Location of Gain/(Loss) 2017 2016 2015 Interest rate swaps Other income $ (391 ) $ 495 $ 3 Interest rate loan commitments Mortgage banking income 49 (123 ) 15 Best efforts forward sales contracts Mortgage banking income (6 ) 79 5 Forward TBA contracts Mortgage banking income (23 ) — — Total $ (371 ) $ 451 $ 23 Credit-risk-related Contingent Features WesBanco has agreements with its derivative counterparties that contain a provision where if WesBanco defaults on any of its indebtedness, including default where repayment of the indebtedness has not been accelerated by the lender, then WesBanco could also be declared in default on its derivative obligations. WesBanco also has agreements with certain of its derivative counterparties that contain a provision where if WesBanco fails to maintain its status as either a well or adequately capitalized institution, then the counterparty could terminate the derivative positions and WesBanco would be required to settle its obligations under the agreements. WesBanco has minimum collateral posting thresholds with certain of its derivative counterparties and has posted collateral with a market value of $3.0 million as of December 31, 2017. If WesBanco had breached any of these provisions at December 31, 2017, it could have been required to settle its obligations under the agreements at the termination value and would have been required to pay any additional amounts due in excess of amounts previously posted as collateral with the respective counterparty.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2017
Retirement Benefits [Abstract]
Employee Benefit Plans	NOTE 13. EMPLOYEE BENEFIT PLANS Defined Benefit Pension Plan— The benefit obligations and funded status of the Plan are as follows: December 31, (dollars in thousands) 2017 2016 Accumulated benefit obligation at end of year $ 119,559 $ 104,775 Change in projected benefit obligation: Projected benefit obligation at beginning of year $ 115,458 $ 109,400 Service cost 2,578 2,799 Interest cost 4,393 5,094 Actuarial (gain) loss 12,172 2,569 Acquisition — 1,392 Benefits paid (4,294 ) (5,796 ) Projected benefit obligation at end of year $ 130,307 $ 115,458 Change in fair value of plan assets: Fair value of plan assets at beginning of year $ 121,597 $ 113,292 Actual return on plan assets 20,119 7,125 Employer contribution 5,000 5,750 Acquisition — 1,226 Benefits paid (4,294 ) (5,796 ) Fair value of plan assets at end of year $ 142,422 $ 121,597 Amounts recognized in the statement of financial position: Funded status $ 12,115 $ 6,139 Net amounts recognized as receivable pension costs in the consolidated balance sheets $ 12,115 $ 6,139 Amounts recognized in accumulated other comprehensive income consist of: Unrecognized prior service cost $ 104 $ 130 Unrecognized net loss 24,336 27,857 Net amounts recognized in accumulated other comprehensive income (before tax) $ 24,440 $ 27,987 Weighted average assumptions used to determine benefit obligations: Discount rate 3.81 % 4.46 % Rate of compensation increase 3.70 % 3.74 % Expected long-term return on assets 6.30 % 6.30 % The components of and weighted-average assumptions used to determine net periodic benefit costs are as follows: For the years ended (dollars in thousands) 2017 2016 2015 Components of net periodic benefit cost: Service cost—benefits earned during year $ 2,578 $ 2,799 $ 3,355 Interest cost on projected benefit obligation 4,393 5,094 4,870 Expected return on plan assets (7,647 ) (7,719 ) (7,735 ) Amortization of prior service cost 26 26 26 Amortization of net loss 3,221 3,020 3,179 Net periodic pension cost $ 2,571 $ 3,220 $ 3,695 Other changes in plan assets and benefit obligations recognized in other comprehensive income: Net (gain) loss for period $ (300 ) $ 3,329 $ (5,106 ) Amortization of prior service cost (26 ) (26 ) (26 ) Amortization of net loss (3,221 ) (3,020 ) (3,179 ) Total recognized in other comprehensive income $ (3,547 ) $ 283 $ (8,311 ) Total recognized in net periodic pension cost and other comprehensive income $ (976 ) $ 3,503 $ (4,616 ) Weighted-average assumptions used to determine net periodic pension cost: Discount rate 4.46 % 4.74 % 4.33 % Rate of compensation increase 3.74 % 3.82 % 3.77 % Expected long-term return on assets 6.30 % 6.79 % 7.00 % On December 31, 2016, WesBanco changed the method used to estimate the service and interest components of net periodic benefit cost for pension benefits. This change compared to the previous method resulted in a decrease in the service and interest components for pension cost. Historically, WesBanco estimated these service and interest cost components utilizing a single weighted-average discount rate derived from the yield curve used to measure the benefit obligation at the beginning of the period. WesBanco has elected to utilize a full yield curve approach in the estimation of these components by applying the specific spot rates along the yield curve used in the determination of the benefit obligation to the relevant projected cash flows. The change has been made to provide a more precise measurement of service and interest costs by improving the correlation between projected benefit cash flows to the corresponding spot yield curve rates. This change does not affect the measurement of the plan’s total benefit obligations as the change in the service and interest costs is completely offset in the actuarial (gain) loss reported. The service cost and interest cost for the plan was reduced by approximately $1.0 million in 2017 as a result of this change. WesBanco accounted for this change as a change in accounting estimate that is inseparable from a change in accounting principle and accordingly accounted for it prospectively. The estimated net loss and prior service credit for the Plan that will be amortized from accumulated other comprehensive income into the net periodic pension cost over the next fiscal year are $2.8 million and $26 thousand, respectively. Unrecognized prior service cost and unrecognized net losses are amortized on a straight-line basis. All unrecognized net losses are being amortized over the average remaining service period of approximately 9 years. The expected long-term rate of return for the Plan’s total assets is based on the expected return of each of the Plan asset categories, weighted based on the median of the target allocation for each class. Pension Plan Investment Policy and Strategy — A maximum of 5% may be invested in any one stock. Foreign stocks may be included, either through direct investment or by the purchase of mutual funds which invest in foreign stock. WesBanco common stock can represent up to 5% of the total market value. Corporate bonds selected for purchase must be rated Baa1 by Moody’s or BBB+ by Standard and Poor’s or higher. No more than 5% shall be invested in bonds or notes issued by the same corporation with a maximum term of twenty years. There is no limit on the holdings of U.S. Treasury or Federal Agency Securities. At December 31, 2017 and 2016, the Plan’s equity securities included 55,300 shares of WesBanco common stock with a fair market value of $2.2 million and $2.4 million, respectively. The following table sets forth the Plan’s weighted-average asset allocations by asset category: Target Allocation for 2017 December 31, 2017 2016 Asset Category: Equity securities 55-75 % 64 % 62 % Debt securities 25-55 % 32 % 35 % Cash and cash equivalents 0-5 % 4 % 3 % Total 100 % 100 % The fair values of WesBanco’s pension plan assets at December 31, 2017 and 2016, by asset category are as follows: December 31, 2017 Fair Value Measurements Using: (in thousands) Assets at Fair Quoted Prices in Significant Significant (Level 3) Defined benefit pension plan assets: Registered investment companies $ 39,799 $ 39,799 $ — $ — Equity securities 64,128 64,128 — — Corporate debt securities 16,147 — 16,147 — Municipal obligations 3,004 — 3,004 — Residential mortgage-backed securities and collateralized mortgage obligations of government agencies 19,322 — 19,322 — Total defined benefit pension plan assets (1) $ 142,400 $ 103,927 $ 38,473 $ — (1) The defined benefit pension plan statement of net assets also includes cash, accrued interest and dividends, and due to/from brokers resulting in net assets available for benefits of $142.4 million. December 31, 2016 Fair Value Measurements Using: (in thousands) Assets at Fair Quoted Prices in Significant Significant (Level 3) Defined benefit pension plan assets: Registered investment companies $ 21,935 $ 21,935 $ — $ — Equity securities 60,144 60,144 — — Corporate debt securities 18,110 — 18,110 — Municipal obligations 2,998 — 2,998 — Residential mortgage-backed securities and collateralized mortgage obligations of government agencies 17,176 — 17,176 — Total defined benefit pension plan assets (1) $ 120,363 $ 82,079 $ 38,284 $ — (1) The defined benefit pension plan statement of net assets also includes cash, accrued interest and dividends, and due to/from brokers resulting in net assets available for benefits of $121.6 million. Registered investment companies and equity securities Corporate debt securities, municipal obligations, and U.S. government agency securities Cash Flows— The following table presents estimated benefits to be paid in each of the next five years and in the aggregate for the five years thereafter ( in thousands Year Amount 2018 $ 4,014 2019 4,524 2020 4,839 2021 5,277 2022 5,599 2023 to 2027 33,631 WesBanco assumed YCB’s obligation for a predecessor bank’s participation in the Pentegra Defined Benefit Plan for Financial Institutions (“Pentegra Plan”). The participating employer plan has been frozen to new participants since 2002. WesBanco spun off the assets from the Pentegra Plan, contributing approximately $2.8 million to satisfy the estimated final costs to do so. This spin off had no impact on earnings as the liability was included in YCB’s balance sheet as of the acquisition date. The distributed assets from the Pentegra Plan were transferred to a plan providing substantially the same benefits to the participants. At December 31, 2017, this plan’s accumulated benefit obligation totaled $9.4 million, and the fair value of plan assets totaled $8.7 million. The net periodic benefit income was $85 thousand, which was calculated using a 3.71% discount rate and a 5.62% expected long-term rate of return. WesBanco had no required minimum contribution to the plan for fiscal 2018; however, WesBanco expects to make a voluntary contribution of $0.2 million. Employee Stock Ownership and 401(k) Plan (“KSOP”)— As of December 31, 2017, the KSOP held 495,090 shares of WesBanco common stock of which all shares were allocated to specific employee accounts. Dividends on shares are either distributed to employee accounts or paid in cash to the participant. Total expense for the KSOP was $3.3 million, $2.8 million, and $2.5 million in 2017, 2016 and 2015, respectively. WesBanco had 415,052 and 445,978 shares registered on Form S-8 remaining for future issuance under the KSOP plan at December 31, 2017 and 2016, respectively. Incentive Bonus, Option and Restricted Stock Plan— Annual Bonus Compensation expense for the Annual Bonus was $1.8 million, $1.6 million and $1.3 million for 2017, 2016, and 2015, respectively. Stock Options On May 16, 2017, WesBanco granted 117,550 stock options to selected participants, including certain named executive officers at an exercise price of $38.88 per share. The options granted in 2017 are service-based and vest in two equal installments on December 31, 2017 and December 31, 2018, and expire seven years from the date of grant. Compensation expense for the stock option component of the Incentive Plan was $0.6 million, $0.5 million and $0.5 million for 2017, 2016 and 2015, respectively. At December 31, 2017, the total unrecognized compensation expense related to non-vested stock option grants totaled $0.4 million with an expense recognition period of one year remaining. The maximum term of options granted under WesBanco’s stock option plan is ten years from the original grant date; however, options granted in 2017 had a term of seven years. The total intrinsic value of options exercised was $0.7 million and $1.2 million for the years ended December 31, 2017 and 2016, respectively. The cash received and related tax benefit realized from stock options exercised was $1.5 million and $0.3 million in 2017 and was $2.5 million and $0.4 million in 2016. Shares issued in connection with options exercised are issued from treasury shares acquired under WesBanco’s share repurchase plans or from issuance of authorized but unissued shares, subject to prior SEC registration. The fair value of stock options granted is estimated at the date of grant using the Black-Scholes option-pricing model. This model requires the input of highly subjective assumptions, changes to which can materially affect the fair value estimate. Additionally, there may be other factors that might otherwise have a significant effect on the value of stock options granted that are not considered by the model. The following table sets forth the significant assumptions used in calculating the fair value of the grants: For the years ended December 31, 2017 2016 2015 Weighted-average life 5.2 years 5.1 years 4.9 years Risk-free interest rate 1.91 % 1.43 % 1.54 % Dividend yield 2.67 % 2.97 % 2.91 % Volatility factor 21.47 % 23.92 % 26.27 % Fair value of the grants $ 6.02 $ 5.09 $ 5.57 The weighted-average life assumption is an estimate of the length of time that an employee might hold an option before option exercise, option expiration or employment termination. The weighted-average life assumption was developed using historical experience. WesBanco used a weighted historical volatility of its common stock price over the weighted average life prior to each issuance as the volatility factor assumption, adjusted for abnormal volatility during certain periods, and current and future dividend payment expectations for the dividend assumption. The following table shows the activity for the Stock Option component of the Incentive Plan: For the year ended Number Weighted Outstanding at beginning of the year 276,122 $ 29.71 Granted during the year 117,550 38.88 Exercised during the year (53,584 ) 27.96 Forfeited or expired during the year (3,400 ) 28.83 Outstanding at end of the year 336,688 $ 33.20 Exercisable at year end 277,913 $ 31.99 The aggregate intrinsic value of the outstanding shares and the shares exercisable at year-end was $2.5 million and $2.4 million, respectively. The following table shows the average remaining life of the stock options at December 31, 2017: Year Issued Exercisable Exercise Options Weighted Weighted Avg. 2011 2,750 $ 19.76 2,750 $ 19.76 0.38 2012 6,750 20.02 6,750 20.02 1.37 2013 24,000 25.00 24,000 25.00 2.37 2014 40,550 28.79 40,550 28.79 3.39 2015 59,488 31.58 59,488 31.58 4.42 2016 85,600 32.37 85,600 32.37 5.40 2017 58,775 38.88 117,550 38.88 6.35 Total 277,913 $ 19.76 to $38.88 336,688 $ 33.20 4.98 Restricted Stock During 2017, WesBanco granted 70,321 shares of restricted stock to certain officers. The restricted shares are service-based and cliff vest 36 months from the date of grant. The weighted average fair value of the restricted stock granted was $38.88 per share. The restricted stock grant provides the recipient with voting rights from the date of issuance. Dividends paid on the restricted shares during the restriction period are converted into additional shares of restricted stock on the date the cash dividend would have otherwise been paid, but do not vest until the related grant of the restricted shares complete their vesting. The Compensation Committee has discretion to elect to pay such dividends to participants. WesBanco also granted 9,003 shares of performance-based restricted stock to select officers. These shares have a three-year performance period, beginning January 1, 2018, based on WesBanco’s return on average assets and return on average tangible common equity measured for each year, compared to a national peer group of financial institutions with total assets between approximately $9 billion and $15 billion. Earned performance-based restricted shares are subject to additional service-based vesting with 50% vesting on May 16, 2021 after the completion of the three-year performance period and the final 50% vesting on May 16, 2022. Dividends paid on the restricted shares during the restriction period are converted into additional shares of restricted stock on the date the cash dividend would have otherwise been paid, but do not vest until the related grant of the restricted shares complete their vesting. The Compensation Committee has discretion to elect to pay such dividends to participants. Compensation expense relating to all restricted stock was $2.1 million, $1.4 million, and $1.2 million in 2017, 2016 and 2015, respectively. At December 31, 2017, the total unrecognized compensation expense related to non-vested restricted stock grants totaled $3.9 million with a weighted average expense recognition period of 1.5 years remaining. The following table shows the activity for the Restricted Stock component of the Incentive Plan: For the year ended December 31, 2017 Restricted Weighted Non-vested at January 1, 2017 170,482 $ 31.40 Granted during the year 79,324 38.88 Vested during the year (42,029 ) 29.13 Forfeited or expired during the year (4,068 ) 31.34 Dividend reinvestment 4,681 40.65 Non-vested at end of the year 208,390 $ 34.91 Total Shareholder Return Plan On November 18, 2015, WesBanco’s Compensation Committee adopted Administrative Rules for a Total Shareholder Return Plan (“TSRP”). The TSRP measures the TSR on WesBanco common stock over a three-year measurement period relative to the return of an established peer group of publicly traded companies over the same performance period. The award is determined at the end of the three-year period if the TSR of WesBanco common stock is equal to or greater than the 50 th percentile of the TSR of the peer group. The number of shares to be earned by the participant shall be 200% of the grant-date award if the TSR of WesBanco common stock is equal to or greater than the 75 th percentile of the TSR of the peer group. Upon achieving the market-based metric, shares determined to be earned by the participant become service-based and vest in three equal annual installments. WesBanco granted 12,000 TSRP shares in 2017 for the performance period beginning January 1, 2017 and ending December 31, 2019 to certain executive officers. While no TSRP shares were granted during 2016, in late 2015 WesBanco granted 12,000 TSRP shares for the performance period beginning January 1, 2016 and ending December 31, 2018 to certain executive officers. The fair value of the market-based awards is based on a Monte-Carlo Simulation valuation of our common stock and our peers’ common stock as of the grant date. Compensation expense relating to the TSR plan was $0.2 million, $0.1 million, and $0 in 2017, 2016 and 2015, respectively. The grant date fair value of the 2017 TSR award was $32.90 per share. At December 31, 2017, the total unrecognized compensation expense related to non-vested TSR awards totaled $0.5 million with a weighted average expense recognition period of 3.0 years remaining.

Other Operating Expenses

Other Operating Expenses	12 Months Ended
	Dec. 31, 2017
Other Income and Expenses [Abstract]
Other Operating Expenses	NOTE 14. OTHER OPERATING EXPENSES Other operating expenses consist of miscellaneous taxes, consulting fees, ATM expenses, postage, supplies, legal fees, communications, other real estate owned and foreclosure expenses, and other expenses. Other operating expenses are presented below: For the years ended December 31, (in thousands) 2017 2016 2015 Franchise and other miscellaneous taxes $ 8,423 $ 6,825 $ 5,924 Consulting, regulatory and advisory fees 6,857 6,270 4,959 ATM and electronic banking interchange expenses 4,510 4,297 4,463 Postage and courier expenses 3,879 3,306 3,720 Supplies 3,033 2,919 2,841 Legal fees 2,781 2,406 2,418 Communications 2,487 1,800 1,537 Other real estate owned and foreclosure expenses 1,097 1,210 546 Other 12,263 11,967 12,479 Total other operating expenses $ 45,330 $ 41,000 $ 38,887

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	NOTE 15. INCOME TAXES On December 22, 2017, H.R.1, commonly known as the Tax Cuts and Jobs Act (the “Act”) was signed into law. The Act reduces WesBanco’s corporate federal rate from 35% to 21% effective January 1, 2018. As a result, WesBanco is required to remeasure deferred tax assets and liabilities using the enacted rate at which WesBanco expects them to be recovered or settled. The effect of this remeasurement is recorded to income tax expense in the year the tax law is enacted. For 2017, the remeasurement of WesBanco’s net deferred tax asset resulted in additional income tax expense of $12.8 million. WesBanco recorded the remeasurement in accordance with SEC Staff Accounting Bulletin No. 118, which provides SEC staff guidance for the application of ASC Topic 740, Income Taxes, in the reporting period in which the 2017 Tax Act was signed into law. As such, the company’s financial results reflect the income tax effects of the 2017 Tax Act for which the accounting under ASC Topic 740 is complete and provisional amounts for those specific income tax effects of the 2017 Tax Act for which the accounting under ASC Topic 740 is incomplete but a reasonable estimate could be determined. The company did not identify items for which the income tax effects of the 2017 Tax Act have not been completed and a reasonable estimate could not be determined as of December 31, 2017. Reconciliation from the federal statutory income tax rate to the effective tax rate is as follows: For the years ended December 31, 2017 2016 2015 Federal statutory tax rate 35.0 % 35.0 % 35.0 % Tax reform remeasurement 8.6 % 0.0 % 0.0 % Net tax-exempt (6.0 %) (7.0 %) (6.8 %) State income taxes, net of federal tax effect 1.3 % 1.4 % 1.6 % Bank-owned life insurance (1.1 %) (1.2 %) (1.6 %) General business credits (1.7 %) (2.1 %) (2.1 %) All other—net 0.2 % 0.3 % (0.1 %) Effective tax rate 36.3 % 26.4 % 26.0 % The provision for income taxes applicable to income before taxes consists of the following: For the years ended December 31, (in thousands) 2017 2016 2015 Current: Federal $ 24,634 $ 18,053 $ 15,661 State 2,061 2,159 2,089 Deferred: Tax reform remeasurement 12,765 — — Federal 13,329 10,519 10,047 State 1,018 305 618 Total $ 53,807 $ 31,036 $ 28,415 The following income tax amounts were recorded in shareholders’ equity as elements of other comprehensive income: For the years ended December 31, (in thousands) 2017 2016 2015 Securities and defined benefit pension plan unrecognized items $ 345 $ (3,480 ) $ (1,202 ) Deferred tax assets and liabilities consist of the following: December 31, (in thousands) 2017 2016 2015 Deferred tax assets: Allowance for loan losses $ 10,389 $ 16,198 $ 15,246 Compensation and benefits 2,536 5,444 6,114 Security gains and losses 821 2,854 2,964 Purchase accounting adjustments 1,565 — 1,275 Partnership adjustments — — 1,921 Non-accrual 1,389 2,392 2,254 Tax credit carryforwards 5,204 12,744 13,580 Net operating loss carryforwards 6,062 12,020 — Fair value adjustments on securities available-for-sale 3,962 5,394 1,979 Other 1,118 5,194 2,264 Gross deferred tax assets 33,046 62,240 47,597 Deferred tax liabilities: Depreciation and amortization (1,883 ) (3,448 ) (1,530 ) Accretion on securities (266 ) (421 ) (2 ) Deferred fees and costs (2,989 ) — — Purchase accounting adjustments — (149 ) — Partnership adjustments (674 ) (1,128 ) — Other (120 ) (2,519 ) (1,511 ) Gross deferred tax liabilities (5,932 ) (7,665 ) (3,043 ) Net deferred tax assets $ 27,114 $ 54,575 $ 44,554 At December 31, 2017 and 2016, WesBanco has a $0.1 million valuation allowance on certain capital loss carryforwards. No valuation allowance was established for the remaining deferred tax assets since management believes that deferred tax assets are likely to be realized through future reversals of existing taxable temporary differences and future taxable income. Under the provisions of the Internal Revenue Code, WesBanco has approximately $5.2 million of alternative minimum tax credits that may be carried forward indefinitely. As a result of the acquisition of YCB, WesBanco has federal net operating loss carryforwards of $25.9 million, which expire between 2030 and 2036; and Indiana net operating loss carryforwards of $20.8 million, which expire between 2031 and 2036. As a result of the previous acquisitions of YCB, ESB, Fidelity, Western Ohio Financial Corporation, Winton Financial Corporation and Oak Hill Financial, Inc., retained earnings at December 31, 2017 and 2016 includes $45.9 million of qualifying and non-qualifying Federal and state income taxes applicable to securities transactions totaled $0.2 million, $0.9 million, and $0.3 million for the years ended December 31, 2017, 2016 and 2015, respectively. At December 31, 2017 and 2016, WesBanco had approximately $0.5 million and $0.4 million, respectively, of unrecognized tax benefits and interest. As of December 31, 2017, $0.5 million of these tax benefits would affect the effective tax rate if recognized. At December 31, 2017 and December 31, 2016, accrued interest related to uncertain tax positions was $23 thousand and $22 thousand, respectively, net of the related federal tax benefit. WesBanco provides for interest and penalties related to uncertain tax positions as part of its provision for federal and state income taxes. WesBanco is subject to U.S. federal income tax as well as to tax in various state income tax jurisdictions. WesBanco, ESB and YCB are no longer subject to any income tax examinations for years prior to 2014. Unrecognized Tax Benefits A reconciliation of the beginning and ending amount of unrecognized tax benefits (excluding interest and the federal income tax benefit of unrecognized state tax benefits) is as follows: For the years ended (in thousands) 2017 2016 2015 Balance at beginning of year $ 436 $ 326 $ 701 Additions based on tax positions related to the current year 101 110 104 Reductions for tax positions of prior years — — (100 ) Reductions due to the statute of limitations (70 ) — (379 ) Settlements — — — Balance at end of year $ 467 $ 436 $ 326

Fair Value Measurement

Fair Value Measurement	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurement	NOTE 16. FAIR VALUE MEASUREMENT Fair value estimates are based on quoted market prices, if available, quoted market prices of similar assets or liabilities, or the present value of expected future cash flows and other valuation techniques. These valuations are significantly affected by discount rates, cash flow assumptions, and risk assumptions used. Therefore, fair value estimates may not be substantiated by comparison to independent markets and are not intended to reflect the proceeds that may be realizable in an immediate settlement of the instruments. Fair value is determined at one point in time and is not representative of future value. These amounts do not reflect the total value of a going concern organization. Management does not have the intention to dispose of a significant portion of its assets and liabilities and therefore, the unrealized gains or losses should not be interpreted as a forecast of future earnings and cash flows. The following is a discussion of assets and liabilities measured at fair value on a recurring basis and valuation techniques applied: Investment securities: Derivatives: WesBanco enters into forward TBA contracts to manage the interest rate risk between the loan commitments to the customer and the closing of the loan for loans that will be sold on a mandatory basis to secondary market investors. The forward TBA contract is reported at fair value in other assets and other liabilities on the consolidated balance sheet with any resulting gain or loss recorded in current periods earnings as mortgage banking income. WesBanco determines the fair value for derivatives using widely accepted valuation techniques including discounted cash flow analysis on the expected cash flows of each derivative. This analysis reflects contractual terms of the derivative, including the period to maturity, and uses observable market based inputs, including interest rate curves and implied volatilities. WesBanco incorporates credit valuation adjustments to appropriately reflect both its own non-performance non-performance We may be required from time to time to measure certain assets and liabilities at fair value on a nonrecurring basis in accordance with GAAP. These adjustments to fair value usually result from the application of lower of cost or market accounting or write-downs of individual assets and liabilities. Impaired loans: Other real estate owned and repossessed assets: Loans held for sale: Certain investments that are measured at fair value using the net asset value per share (or its equivalent) practical expedient have not been categorized in the fair value hierarchy. The fair value amounts presented in the table below are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the statement of financial position. The following tables set forth WesBanco’s financial assets and liabilities that were accounted for at fair value on a recurring and nonrecurring basis by level within the fair value hierarchy as of December 31, 2017 and 2016: December 31, 2017 Fair Value Measurements Using: (in thousands) December 31, Quoted Prices in Significant Significant Investments Recurring fair value measurements Trading securities $ 7,844 $ 5,778 $ — $ — $ 2,066 Securities—available-for-sale U.S. Government sponsored entities and agencies 71,843 — 71,843 — — Residential mortgage-backed securities and collateralized mortgage obligations of government agencies 934,922 — 934,922 — — Commercial mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 114,867 — 114,867 — — Obligations of state and political subdivisions 104,830 — 104,830 — — Corporate debt securities 35,403 — 35,403 — — Equity securities 5,613 5,613 — — — Total securities—available-for-sale $ 1,267,478 $ 5,613 $ 1,261,865 $ — $ — Loans held for sale $ 20,320 $ — $ 20,320 $ — $ — Other assets—interest rate derivatives agreements $ 7,351 $ — $ 7,351 $ — $ — Total assets recurring fair value measurements $ 1,302,993 $ 11,391 $ 1,289,536 $ — $ 2,066 Other liabilities—interest rate derivatives agreements $ 7,345 $ — $ 7,345 $ — $ — Total liabilities recurring fair value measurements $ 7,345 $ — $ 7,345 $ — $ — Nonrecurring fair value measurements Impaired loans $ 1,717 $ — $ — $ 1,717 $ — Other real estate owned and repossessed assets 5,297 — — 5,297 — Total nonrecurring fair value measurements $ 7,014 $ — $ — $ 7,014 $ — December 31, 2016 Fair Value Measurements Using: (in thousands) December 31, Quoted Prices in (level 1) Significant Significant Investments Recurring fair value measurements Trading securities $ 7,071 $ 5,633 $ — $ — $ 1,438 Securities—available-for-sale U.S. Government sponsored entities and agencies 54,043 — 54,043 — — Residential mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 938,289 — 938,289 — — Commercial mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 96,810 — 96,810 — — Obligations of state and political subdivisions 111,663 — 111,663 — — Corporate debt securities 35,301 — 35,301 — — Equity securities 5,070 2,938 2,132 — — Total securities—available-for-sale $ 1,241,176 $ 2,938 $ 1,238,238 $ — $ — Other assets—interest rate derivatives agreements $ 5,596 $ — $ 5,596 $ — $ — Total assets recurring fair value measurements $ 1,253,843 $ 8,571 $ 1,243,834 $ — $ 1,438 Other liabilities—interest rate derivatives agreements $ 5,199 — $ 5,199 — — Total liabilities recurring fair value measurements $ 5,199 $ — $ 5,199 $ — $ — Nonrecurring fair value measurements Impaired loans $ 3,405 $ — $ — $ 3,405 $ — Other real estate owned and repossessed assets 8,346 — — 8,346 — Loans held for sale 17,315 — 17,315 — — Total nonrecurring fair value measurements $ 29,066 $ — $ 17,315 $ 11,751 $ — WesBanco’s policy is to recognize transfers between levels as of the actual date of the event or change in circumstances that caused the transfer. There were no significant transfers between levels 1, 2, or 3 for the years ended December 31, 2017 and 2016. The following table presents additional quantitative information about assets measured at fair value on a nonrecurring basis and for which WesBanco has utilized level 3 inputs to determine fair value: Quantitative Information about Level 3 Fair Value Measurements (in thousands) Fair Value Valuation Techniques Unobservable Input Range / Weighted Average December 31, 2017: Impaired loans $ 1,717 Appraisal of collateral (1) Appraisal adjustments (2) (4.8%) /(4.8%) Liquidation expenses (2) (7.6%) /(7.6%) Other real estate owned and repossessed assets 5,297 Appraisal of collateral (1)(3) December 31, 2016: Impaired loans $ 3,405 Appraisal of collateral (1) Appraisal adjustments (2) 0% to (70.0%) /(36.6%) Liquidation expenses (2) (1.5%) to (8.0%) /(4.6%) Other real estate owned and repossessed assets 8,346 Appraisal of collateral (1)(3) (1) Fair value is generally determined through independent appraisals of the underlying collateral, which generally include various level 3 inputs which are not identifiable. (2) Appraisals may be adjusted by management for qualitative factors such as economic conditions and estimated liquidation expenses. The range and weighted average of appraisal adjustments and liquidation expenses are presented as a percent of the appraisal. (3) Includes estimated liquidation expenses and numerous dissimilar qualitative adjustments by management which are not identifiable. The estimated fair values of WesBanco’s financial instruments are summarized below: Carrying Fair Value Fair Value Measurements at December 31, 2017 (in thousands) Quoted Prices in (level 1) Significant (level 2) Significant (level 3) Investments Financial Assets Cash and due from banks $ 117,572 $ 117,572 $ 117,572 $ — $ — $ — Trading securities 7,844 7,844 5,778 — — 2,066 Securities available-for-sale 1,267,478 1,267,478 5,613 1,261,865 — — Securities held-to-maturity 1,009,500 1,023,784 — 1,023,191 593 — Net loans 6,296,157 6,212,823 — — 6,212,823 — Loans held for sale 20,320 20,320 — 20,320 — — Other assets—interest rate derivatives 7,351 7,351 — 7,351 — — Accrued interest receivable 29,728 29,728 29,728 — — — Financial Liabilities Deposits 7,043,588 7,053,536 5,766,531 1,287,005 — — Federal Home Loan Bank borrowings 948,203 944,706 — 944,706 — — Other borrowings 184,805 184,814 182,785 2,029 — — Subordinated debt and junior subordinated debt 164,327 146,484 — 146,484 — — Other liabilities—interest rate derivatives 7,345 7,345 — 7,345 — — Accrued interest payable 3,178 3,178 3,178 — — — Carrying Fair Value Fair Value Measurements at December 31, 2016 (in thousands) Quoted Significant Significant Investments Financial Assets Cash and due from banks $ 128,170 $ 128,170 $ 128,170 $ — $ — $ — Trading securities 7,071 7,071 5,633 — — 1,438 Securities available-for-sale 1,241,176 1,241,176 2,938 1,238,238 — — Securities held-to-maturity 1,067,967 1,076,790 — 1,076,189 601 — Net loans 6,205,762 6,073,558 — — 6,073,558 — Loans held for sale 17,315 17,315 — 17,315 — — Other assets—interest rate derivatives 5,596 5,596 — 5,596 — — Accrued interest receivable 28,299 28,299 28,299 — — — Financial Liabilities Deposits 7,040,879 7,052,501 5,545,057 1,507,444 — — Federal Home Loan Bank borrowings 968,946 974,430 — 974,430 — — Other borrowings 199,376 199,385 197,164 2,221 — — Subordinated debt and junior subordinated debt 163,598 134,859 — 134,859 — — Other liabilities—interest rate derivatives 5,199 5,199 — 5,199 — — Accrued interest payable 2,204 2,204 2,204 — — — The following methods and assumptions were used to measure the fair value of financial instruments recorded at cost on WesBanco’s consolidated balance sheets: Cash and due from banks: Securities held-to-maturity: held-to-maturity Net loans: Accrued interest receivable: . Deposits: Federal Home Loan Bank borrowings: Other borrowings: Subordinated debt and junior subordinated debt: Accrued interest payable: Off-balance Off-balance

Comprehensive Income_(Loss)

Comprehensive Income/(Loss)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Comprehensive Income/(Loss)	NOTE 17. COMPREHENSIVE INCOME/(LOSS) The activity in accumulated other comprehensive income/(loss) for the years ended December 31, 2017, 2016 and 2015 is as follows: Accumulated Other Comprehensive Income/(Loss) (1) (in thousands) Defined Unrealized Gains Available-for-Sale Unrealized Gains Available-for-Sale to Held-to-Maturity Total Balance at December 31, 2016 $ (17,758 ) $ (9,890 ) $ 522 $ (27,126 ) Other comprehensive income/(loss) before reclassifications 239 (985 ) — (746 ) Amounts reclassified from accumulated other comprehensive income/(loss) 2,194 (27 ) (209 ) 1,958 Period change 2,433 (1,012 ) (209 ) 1,212 Adoption of accounting standard ASU 2018-02 (3,301 ) (2,348 ) 68 (5,581 ) Balance at December 31, 2017 $ (18,626 ) $ (13,250 ) $ 381 $ (31,495 ) Balance at December 31, 2015 $ (17,539 ) $ (4,162 ) $ 747 $ (20,954 ) Other comprehensive income/(loss) before reclassifications (2,112 ) (4,300 ) — (6,412 ) Amounts reclassified from accumulated other comprehensive income/(loss) 1,893 (1,428 ) (225 ) 240 Period change (219 ) (5,728 ) (225 ) (6,172 ) Balance at December 31, 2016 $ (17,758 ) $ (9,890 ) $ 522 $ (27,126 ) Balance at December 31, 2014 $ (22,776 ) $ 2,892 $ 1,059 $ (18,825 ) Other comprehensive income/(loss) before reclassifications 3,233 (6,677 ) — (3,444 ) Amounts reclassified from accumulated other comprehensive income/(loss) 2,004 (377 ) (312 ) 1,315 Period change 5,237 (7,054 ) (312 ) (2,129 ) Balance at December 31, 2015 $ (17,539 ) $ (4,162 ) $ 747 $ (20,954 ) (1) All amounts are net of tax. Related income tax expense or benefit is calculated using a combined Federal and State income tax rate approximating 37%. Details about Accumulated Other Comprehensive Amounts Reclassified from Affected Line Item in the Statement of Net (in thousands) 2017 2016 2015 Securities available-for-sale Net securities gains reclassified into earnings $ (42 ) $ (2,251 ) $ (596 ) Net securities gains (Non-interest Related income tax expense 15 823 219 Provision for income taxes Net effect on accumulated other comprehensive income/(loss) for the period (27 ) (1,428 ) (377 ) Securities held-to-maturity Amortization of unrealized gain transferred from available-for-sale (326 ) (357 ) (494 ) Interest and dividends on securities (Interest and dividend income) Related income tax expense 117 132 182 Provision for income taxes Net effect on accumulated other comprehensive income/(loss) for the period (209 ) (225 ) (312 ) Defined benefit pension plan (2): Amortization of net loss and prior service costs 3,247 3,046 3,205 Employee benefits (Non-interest Related income tax benefit (1,053 ) (1,153 ) (1,201 ) Provision for income taxes Net effect on accumulated other comprehensive income/(loss) for the period 2,194 1,893 2,004 Total reclassifications for the period $ 1,958 $ 240 $ 1,315 (1) For additional detail related to unrealized gains on securities and related amounts reclassified from accumulated other comprehensive income/(loss) see Note 4, “Securities.” (2) Included in the computation of net periodic pension cost. See Note 13, “Employee Benefit Plans” for additional detail.

Commitments and Contingent Liab

Commitments and Contingent Liabilities	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingent Liabilities	NOTE 18. COMMITMENTS AND CONTINGENT LIABILITIES Commitments— off-balance non-performance Letters of credit are conditional commitments issued by banks to guarantee the performance of a customer to a third party. Those guarantees are primarily issued to support public and private borrowing arrangements, including normal business activities, bond financing and similar transactions. Letters of credit are considered guarantees. The liability associated with letters of credit was $0.2 million as of December 31, 2017 and 2016. Contingent obligations to purchase loans funded by other entities include affordable housing plan guarantees, andcredit card guarantees. Affordable housing plan guarantees are performance guarantees for various building project loans. The guarantee amortizes as the loan balances decrease. Credit card guarantees are credit card balances not owned by WesBanco, whereby the Bank guarantees the performance of the cardholder. The following table presents total commitments to extend credit, guarantees and various letters of credit outstanding: December 31, (in thousands) 2017 2016 Lines of credit $ 1,452,697 $ 1,418,329 Loans approved but not closed 245,644 185,254 Overdraft limits 126,671 126,517 Letters of credit 31,951 32,907 Contingent obligations to purchase loans funded by other entities 6,700 13,036 Contingent Liabilities—

Wesbanco Bank Community Develop

Wesbanco Bank Community Development Corporation	12 Months Ended
	Dec. 31, 2017
Text Block [Abstract]
Wesbanco Bank Community Development Corporation	NOTE 19. WESBANCO BANK COMMUNITY DEVELOPMENT CORPORATION WesBanco Bank Community Development Corporation (“WBCDC”), a consolidated subsidiary of WesBanco Bank, is a Certified Development Entity (“CDE”) with $60.0 million of New Markets Tax Credits (“NMTC”) all of which had been invested in WBCDC at December 31, 2017. The NMTC program is administered by the Community Development Financial Institutions Fund of the U.S. Treasury and is aimed at stimulating economic and community development and job creation in low-income low-income The credit provided to the investor totals 39% of each QEI in a CDE and is claimed over a seven-year credit allowance period. In each of the first three years, the investor receives a credit equal to 5% of the total amount the investor paid to the CDE for each QEI. For each of the remaining four years, the investor receives a credit equal to 6% of the total amount the investor paid to the CDE for each QEI. As of December 31, 2017, WesBanco has received $22.4 million in tax credits over the seven-year credit allowance periods for its $60.0 million NMTC authority invested in WBCDC. WesBanco is eligible to receive an additional $1.0 million in tax credits as set forth in the following table with respect to aggregate QEI amounts invested with a remaining seven-year credit allowance period. WesBanco Bank recognized $1.0 million, $1.8 million and $1.9 million in NMTC in its income tax provision for the years ended December 31, 2017, 2016 and 2015, respectively. These tax credits are subject to certain general business tax credit limitations, as well as the alternative minimum tax, and are therefore limited in deductibility currently due to the applicability of alternative minimum tax on WesBanco’s federal income tax return. No NMTC have been carried forward to future tax years. ( in thousands ) Aggregate QEI New Markets Tax Credit Year 2018 2019 2012 $ 6,000 $ 360 $ — 2013 5,000 300 300 Total $ 11,000 $ 660 $ 300 (1) The seven-year credit allowance period has expired for $49.0 million in QEI investments in WBCDC. The NMTC claimed by WesBanco Bank with respect to each QEI remain subject to recapture over each QEI’s credit allowance period upon the occurrence of any of the following: • if less than substantially all (generally defined as 85%) of the QEI proceeds are not used by WBCDC to make qualified low income community investments; • WBCDC ceases to be a CDE; or • WBCDC redeems its QEI investment prior to the end of the current credit allowance periods. At December 31, 2017, 2016 and 2015, none of the above recapture events had occurred, nor in the opinion of management are such events anticipated to occur in the foreseeable future. The following condensed financial statements summarize the financial position of WBCDC as of December 31, 2017, and the results of its operations and cash flows for the year ended December 31, 2017: BALANCE SHEET (in thousands) December 31, Assets Cash and due from banks $ 36,533 Loans, net of allowance for loan losses of $254 35,218 Investments 820 Other assets 195 Total Assets $ 72,766 Liabilities $ 354 Shareholder Equity 72,412 Total Liabilities and Shareholder Equity $ 72,766 STATEMENT OF INCOME (in thousands) For the year ended Interest income Loans $ 1,282 Total interest income 1,282 Provision for loan losses 5 Net interest income after provision for loan losses 1,277 Loss on investments (148 ) Non-interest 235 Income before provision for income taxes 894 Provision for income taxes 354 Net income $ 540 STATEMENT OF CASH FLOWS (in thousands) For the year ended Operating Activities Net income $ 540 Provision for loan losses 5 Loss on investments 148 Net change in other assets 91 Net change in other liabilities 80 Net cash provided by operating activities 864 Investing Activities Decrease in loans 4,366 Net cash provided by investing activities 4,366 Financing Activities Qualified equity investment by parent company — Net cash provided by financing activities — Net increase in cash and cash equivalents 5,230 Cash and cash equivalents at beginning of year 31,303 Cash and cash equivalents at end of year $ 36,533

Transactions with Related Parti

Transactions with Related Parties	12 Months Ended
	Dec. 31, 2017
Related Party Transactions [Abstract]
Transactions with Related Parties	NOTE 20. TRANSACTIONS WITH RELATED PARTIES Certain directors and officers (including their affiliates, families and entities in which they are principal owners) of WesBanco and its subsidiaries are customers of, or suppliers to, those subsidiaries and have had, and are expected to have, transactions with the subsidiaries in the ordinary course of business. In addition, certain directors are also directors or officers of corporations that are customers of, or suppliers to, the Bank and have had, and are expected to have, transactions with the Bank in the ordinary course of business. In the opinion of management, such transactions are consistent with prudent banking practices and are within applicable banking regulations. Indebtedness of related parties aggregated approximately $16.7 million, $18.7 million and $9.6 million as of December 31, 2017, 2016, and 2015, respectively. During 2017, $4.3 million in related party loans were funded and $6.3 million were repaid or no longer related. At December 31, 2017, 2016 and 2015, none of the outstanding related party loans were past due 90 days or more, on non-accrual,

Regulatory Matters

Regulatory Matters	12 Months Ended
	Dec. 31, 2017
Banking and Thrift [Abstract]
Regulatory Matters	NOTE 21. REGULATORY MATTERS The Federal Reserve Bank is the primary regulator for the parent company, WesBanco. WesBanco Bank is a state non-member WesBanco and WesBanco Bank are also required to maintain non-interest Additionally, WesBanco and WesBanco Bank are subject to various regulatory capital requirements (risk-based capital ratios) administered by federal banking agencies. Failure to meet minimum capital requirements can initiate certain mandatory and possibly additional discretionary actions by the regulators that, if undertaken, could have a material adverse effect on WesBanco’s financial results. All bank holding companies and banking subsidiaries are required to have common equity Tier 1 (“CET1”) of at least 4.5%, core capital (“Tier 1”) of at least 6% of risk-weighted assets, total capital of at least 8% of risk-weighted assets, and a minimum Tier 1 leverage ratio of 4%. Tier 1 capital consists principally of shareholders’ equity; excluding items recorded in accumulated other comprehensive income, less goodwill and other intangibles. Total capital consists of Tier 1 capital plus the allowance for loan losses subject to limitation. The regulations also define “well-capitalized” levels of CET1, Tier 1 risk-based capital, total risk-based capital, and Tier 1 leverage capital as 6.5%, 8%, 10%, and 5%, respectively. WesBanco and WesBanco Bank were categorized as “well-capitalized” under the Federal Deposit Insurance Corporation Improvement Act at December 31, 2017 and 2016. There are no conditions or events since December 31, 2017 that management believes have changed WesBanco’s “well-capitalized” category. The Basel III capital standards, effective January 1, 2015 with a phase-in WesBanco currently has $138.6 million in junior subordinated debt in its Consolidated Balance Sheets presented as a separate category of long-term debt. For regulatory purposes, trust preferred securities totaling $138.0 million, issued by unconsolidated trust subsidiaries of WesBanco underlying such junior subordinated debt, are considered Tier 1 capital in accordance with current regulatory reporting requirements. The following table summarizes risk-based capital amounts and ratios for WesBanco and the Bank: December 31, 2017 December 31, 2016 (dollars in thousands) Minimum Well Amount Ratio Minimum Amount Ratio Minimum WesBanco, Inc. Tier 1 leverage 4.00 % 5.00 % $ 970,425 10.39 % $ 373,566 $ 901,873 9.81 % $ 367,843 Common equity Tier 1 4.50 % 6.50 % 834,554 12.14 % 309,298 773,306 11.28 % 308,462 Tier 1 capital to risk-weighted assets 6.00 % 8.00 % 970,425 14.12 % 412,397 901,873 13.16 % 411,283 Total capital to risk-weighted assets 8.00 % 10.00 % 1,042,124 15.16 % 549,863 971,762 14.18 % 548,378 WesBanco Bank, Inc. Tier 1 leverage 4.00 % 5.00 % $ 869,227 9.32 % $ 372,900 $ 827,173 9.02 % $ 366,903 Common equity Tier 1 4.50 % 6.50 % 869,227 12.66 % 308,900 827,173 12.10 % 307,728 Tier 1 capital to risk-weighted assets 6.00 % 8.00 % 869,227 12.66 % 411,866 827,173 12.10 % 410,305 Total capital to risk-weighted assets 8.00 % 10.00 % 940,303 13.70 % 549,155 896,598 13.11 % 547,073 (1) Minimum requirements to remain adequately capitalized. (2) Well capitalized under prompt corrective action regulations.

Condensed Parent Company Financ

Condensed Parent Company Financial Statements	12 Months Ended
	Dec. 31, 2017
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Parent Company Financial Statements	NOTE 22. CONDENSED PARENT COMPANY FINANCIAL STATEMENTS Presented below are the Condensed Balance Sheets, Statements of Income and Statements of Cash Flows for the parent company: BALANCE SHEETS December 31, (in thousands) 2017 2016 ASSETS Cash and short-term investments $ 75,911 $ 47,035 Investment in subsidiaries—Bank 1,431,021 1,404,565 Investment in subsidiaries—Nonbank 7,755 8,228 Securities available-for-sale, 2,687 2,133 Other assets 28,614 28,602 Total Assets $ 1,545,988 $ 1,490,563 LIABILITIES Junior subordinated debt owed to unconsolidated subsidiary trusts $ 138,564 $ 137,559 Dividends payable and other liabilities 12,103 11,596 Total Liabilities 150,667 149,155 SHAREHOLDERS’ EQUITY 1,395,321 1,341,408 Total Liabilities and Shareholders’ Equity $ 1,545,988 $ 1,490,563 STATEMENTS OF INCOME For the years ended December 31, (in thousands) 2017 2016 2015 Dividends from subsidiaries—Bank $ 72,000 $ 85,000 $ 60,000 Dividends from subsidiaries—Nonbank 2,520 800 500 Income from securities 73 75 75 Other income 203 147 104 Total income 74,796 86,022 60,679 Interest expense 6,032 4,136 3,315 Other expense 4,004 5,628 5,547 Total expense 10,036 9,764 8,862 Income before income tax benefit and undistributed net income of subsidiaries 64,760 76,258 51,817 Income tax benefit (4,726 ) (3,149 ) (2,971 ) Income before undistributed net income of subsidiaries 69,486 79,407 54,788 Equity in undistributed net income of subsidiaries 24,996 7,228 25,974 NET INCOME $ 94,482 $ 86,635 $ 80,762 The details of other comprehensive income and accumulated other comprehensive income are included in the consolidated financial statements. STATEMENTS OF CASH FLOWS For the years ended December 31, (in thousands) 2017 2016 2015 OPERATING ACTIVITIES Net income $ 94,482 $ 86,635 $ 80,762 Adjustments to reconcile net income to net cash provided by operating activities: Equity in undistributed net income (24,996 ) (7,228 ) (25,974 ) Decrease in other assets 566 14,679 199 Other—net 2,848 2,094 1,657 Net cash provided by operating activities 72,900 96,180 56,644 INVESTING ACTIVITIES Proceed from sales —securities available-for-sale — — 210 Purchase of securities —securities available-for-sale (200 ) — — Acquisitions and additional capitalization of subsidiaries, net of cash (paid) acquired — (43,199 ) 1,465 Net cash (used in) provided by investing activities (200 ) (43,199 ) 1,675 FINANCING ACTIVITIES Repayment of junior subordinated debt — — (36,083 ) Repayment of other borrowings — — (13,000 ) Issuance of common stock 1,040 1,713 — Repurchase of common stock warrant — — (2,247 ) Treasury shares (purchased) sold—net — (3,026 ) (2,542 ) Dividends paid to common and preferred shareholders (44,864 ) (37,805 ) (33,007 ) Net cash used in financing activities (43,824 ) (39,118 ) (86,879 ) Net increase (decrease) in cash and cash equivalents 28,876 13,863 (28,560 ) Cash and short-term investments at beginning of year 47,035 33,172 61,732 Cash and short-term investments at end of year $ 75,911 $ 47,035 $ 33,172

Business Segments

Business Segments	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Business Segments	NOTE 23. BUSINESS SEGMENTS WesBanco operates two reportable segments: (i) Community Banking and (ii) Trust and Investment Services. WesBanco’s community banking segment offers services traditionally offered by full-service commercial banks, including commercial demand, individual demand and time deposit accounts, as well as commercial, mortgage and individual installment loans, and certain non-traditional Condensed financial information by business segment is presented below: (in thousands) Community Trust and Consolidated For the year ended December 31, 2017: Interest and dividend income $ 332,424 $ — 332,424 Interest expense 42,129 — 42,129 Net interest income 290,295 — 290,295 Provision for credit losses 9,986 — 9,986 Net interest income after provision for credit losses 280,309 — 280,309 Non-interest 66,100 22,740 88,840 Non-interest 207,441 13,419 220,860 Income before provision for income taxes 138,968 9,321 148,289 Provision for income taxes 50,079 3,728 53,807 Net income $ 88,889 $ 5,593 $ 94,482 For the year ended December 31, 2016: Interest and dividend income $ 286,097 $ — $ 286,097 Interest expense 32,767 — 32,767 Net interest income 253,330 — 253,330 Provision for credit losses 8,478 — 8,478 Net interest income after provision for credit losses 244,852 — 244,852 Non-interest 59,869 21,630 81,499 Non-interest 196,784 11,896 208,680 Income before provision for income taxes 107,937 9,734 117,671 Provision for income taxes 27,142 3,894 31,036 Net income $ 80,795 $ 5,840 $ 86,635 For the year ended December 31, 2015: Interest and dividend income $ 261,712 $ — $ 261,712 Interest expense 24,725 — 24,725 Net interest income 236,987 — 236,987 Provision for credit losses 8,353 — 8,353 Net interest income after provision for credit losses 228,634 — 228,634 Non-interest 52,566 21,900 74,466 Non-interest 181,821 12,102 193,923 Income before provision for income taxes 99,379 9,798 109,177 Provision for income taxes 24,496 3,919 28,415 Net income $ 74,883 $ 5,879 $ 80,762 Total non-fiduciary

Condensed Quarterly Statements

Condensed Quarterly Statements of Income (Unaudited)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Condensed Quarterly Statements of Income (Unaudited)	NOTE 24. CONDENSED QUARTERLY STATEMENTS OF INCOME (UNAUDITED) The following tables set forth unaudited consolidated selected quarterly statements of income for the years ended December 31, 2017 and 2016. 2017 Quarter ended (dollars in thousands, except per share amounts) March 31, June 30, September 30, December 31, Annual Total Interest and dividend income $ 79,924 $ 82,160 $ 85,489 $ 84,851 $ 332,424 Interest expense 9,205 10,021 11,235 11,669 42,129 Net interest income 70,719 72,139 74,254 73,182 290,295 Provision for credit losses 2,711 2,383 2,516 2,376 9,986 Net interest income after provision for credit losses 68,008 69,756 71,738 70,806 280,309 Non-interest 22,872 21,628 20,893 22,878 88,273 Net securities gains 12 494 6 56 567 Non-interest 54,384 55,884 55,754 54,837 220,860 Income before provision for income taxes 36,508 35,994 36,883 38,903 148,289 Provision for income taxes 10,622 9,653 10,527 23,006 53,807 Net income $ 25,886 $ 26,341 $ 26,356 $ 15,897 $ 94,482 Earnings per common share—basic $ 0.59 $ 0.60 $ 0.60 $ 0.36 $ 2.15 Earnings per common share—diluted $ 0.59 $ 0.60 $ 0.60 $ 0.36 $ 2.14 2016 Quarter ended (dollars in thousands, except per share amounts) March 31, June 30, September 30, December 31, Annual Interest and dividend income $ 67,601 $ 67,585 $ 70,092 $ 80,819 $ 286,097 Interest expense 7,759 7,811 8,066 9,131 32,767 Net interest income 59,842 59,774 62,026 71,688 253,330 Provision for credit losses 2,324 1,811 2,214 2,128 8,478 Net interest income after provision for credit losses 57,518 57,963 59,812 69,560 244,852 Non-interest 18,282 19,006 20,419 21,357 79,142 Net securities gains 1,111 585 598 63 2,357 Non-interest 45,343 47,360 57,601 58,298 208,680 Income before provision for income taxes 31,568 30,194 23,228 32,682 117,671 Provision for income taxes 8,694 8,085 5,793 8,464 31,036 Net income $ 22,874 $ 22,109 $ 17,435 $ 24,218 $ 86,635 Earnings per common share—basic $ 0.60 $ 0.58 $ 0.44 $ 0.55 $ 2.16 Earnings per common share—diluted $ 0.60 $ 0.58 $ 0.44 $ 0.55 $ 2.16

Summary of Significant Accoun33

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Nature of Operations	Nature of Operations—
Use of Estimates	Use of Estimates—
Principles of Consolidation	Principles of Consolidation— WesBanco determines whether it has a controlling financial interest in an entity by first evaluating whether the entity is a voting interest entity or a variable interest entity. A voting interest entity is an entity in which the total equity investment at risk is sufficient to enable the entity to finance itself independently and provides the equity holders with the obligation to absorb losses, the right to receive residual returns and the right to make financial and operating decisions. WesBanco consolidates voting interest entities in which it owns all, or at least a majority (generally, greater than 50%) of the voting interest.
Variable Interest Entities	Variable Interest Entities— A controlling financial interest in a VIE is present when an enterprise has both the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and the obligation to absorb losses of the VIE that could potentially be significant to the VIE or the right to receive benefits of the VIE that could potentially be significant to the VIE. A VIE often holds financial assets, including loans or receivables, real estate or other property. The company with a controlling financial interest, known as the primary beneficiary, is required to consolidate the VIE. WesBanco has twelve wholly-owned trust subsidiaries (collectively, the “Trusts”), for which it does not absorb a majority of expected losses or receive a majority of the expected residual returns. Accordingly, the Trusts and their net assets are not included in the Consolidated Financial Statements. However, the junior subordinated deferrable interest debentures issued by WesBanco to the Trusts (refer to Note 11, “Subordinated Debt and Junior Subordinated Debt”) and the common stock issued by the Trusts is included in the Consolidated Balance Sheets. WesBanco also owns non-controlling variable interests in certain limited partnerships for which it does not absorb a majority of expected losses or receive a majority of expected residual returns. These VIEs are not consolidated into WesBanco’s financial statements because WesBanco is not considered the primary beneficiary. These investments are accounted for using the equity method of accounting and are included in other assets in the Consolidated Balance Sheets. Refer to Note 8, “Investments in Limited Partnerships” for further detail.
Revenue Recognition	Revenue Recognition—
Cash and Cash Equivalents	Cash and Cash Equivalents—
Securities	Securities— Trading securities: Available-for-sale securities: Held-to-maturity securities: Cost method investments: Securities acquired in acquisitions are recorded at fair value with the premium or discount derived from the fair market value adjustment recognized into interest income on a level yield basis over the remaining life of the security. Gains and losses: Amortization and accretion: Other-than-temporary impairment losses:
Loans and Loans Held for Sale	Loans and Loans Held for Sale— Performing loans acquired in acquisitions are recorded at fair value with no carryover of related allowance for credit losses. The premium or discount derived from the fair market value adjustment is recognized into interest income using a level yield method over the remaining expected life of the loan. Refer to the “Acquired Loans” policy below for additional detail. Loan origination fees and direct costs are deferred and accreted or amortized into interest income, as an adjustment to the yield, over the life of the loan using the level yield method. When a loan is paid off, the remaining unaccreted or unamortized net origination fees or costs are immediately recognized into income. Loans are generally placed on non-accrual when they are 90 days past due, unless the loan is well-secured and in the process of collection. Loans may be returned to accrual status when a borrower has resumed paying principal and interest for a sustained period of at least six months and the Bank is reasonably assured of collecting the remaining contractual principal and interest. Loans are returned to accrual status at an amount equal to the principal balance of the loan at the time of non-accrual status less any payments applied to principal during the non-accrual period. Loans are reported as a troubled debt restructuring when WesBanco for economic or legal reasons related to a borrower’s financial difficulties grants a concession to the borrower that it would not otherwise consider. Refer to the “Troubled Debt Restructuring” policy below for additional detail. A loan is considered impaired, based on current information and events, if it is probable that WesBanco will be unable to collect the payments of principal and interest when due according to the contractual terms of the loan agreement. Impaired loans include all non-accrual loans and troubled debt restructurings. WesBanco recognizes interest income on non-accrual loans on the cash basis only if recovery of principal is reasonably assured. Consumer loans are charged down to the net realizable value at 120 days past due for closed-end loans and 180 days past due for open-end revolving lines of credit. Residential real estate loans are charged down to the net realizable value of the collateral at 180 days past due. Commercial loans are charged down to the net realizable value when it is determined that WesBanco will be unable to collect the principal amount in full. Loans are reclassified to other assets at the net realizable value when foreclosure or repossession of the collateral occurs. Refer to the “Other Real Estate Owned and Repossessed Assets” policy below for additional detail.
Troubled Debt Restructurings ("TDR")	Troubled Debt Restructurings (“TDR”)— When determining whether a debtor is experiencing financial difficulties, consideration is given to any known default on any of its debt or whether it is probable that the debtor would be in payment default in the foreseeable future without the modification. Other indicators of financial difficulty include whether the debtor has declared or is in the process of declaring bankruptcy, the debtor’s ability to continue as a going concern, or the debtor’s projected cash flow to service its debt (including principal & interest) in accordance with the contractual terms for the foreseeable future, without a modification. If the payment of principal at original maturity is primarily dependent on the value of collateral, the current value of that collateral is considered in determining whether the principal will be paid. The restructuring of a loan does not have a material effect on the allowance or provision for credit losses as the internal risk grade of a loan has more influence on the allowance than the classification of a loan as a TDR. The internal risk rating is the primary factor for establishing the allowance for commercial loans, including commercial real estate except for loans that are individually evaluated for impairment, in which case a specific reserve is established pursuant to GAAP. Portfolio segment loss history is the primary factor for establishing the allowance for residential real estate, home equity and consumer loans. Non-accrual loans that are restructured remain on non-accrual, but may move to accrual status after they have performed according to the restructured terms for a period of time. TDRs on accrual status generally remain on accrual as long as they continue to perform in accordance with their modified terms. TDRs may also be placed on non-accrual if they do not perform in accordance with the restructured terms. Loans may be removed from TDR status after they have performed according to the renegotiated terms for a period of time if the interest rate under the modified terms is at or above market, or if the loan returns to its original terms.
Acquired Loans	Acquired Loans Acquired loans that meet the criteria for non-accrual of interest prior to acquisition are considered to be performing upon acquisition, regardless of whether the customer is contractually delinquent, if WesBanco can reasonably estimate the timing and amount of expected cash flows on such loans. Accordingly, WesBanco does not consider acquired contractually delinquent loans to be non-accrual or non-performing and continues to recognize interest income on these loans using the accretion method. Loans acquired with deteriorated credit quality are accounted for in accordance with Accounting Standards Codification (“ASC”) 310-30, Loans and Debt Securities Acquired with Deteriorated Credit Quality (ASC 310-30) if, at acquisition, the loans have evidence of credit quality deterioration since origination and it is probable that all contractually required payments will not be collected. At acquisition, WesBanco considers several factors as indicators that an acquired loan has evidence of deterioration in credit quality. These factors include loans 90 days or more past due, loans with an internal risk grade of substandard or below, loans classified as non-accrual by the acquired institution, and loans that have been previously modified in a troubled debt restructuring. Under the ASC 310-30 model, the excess of cash flows expected to be collected at acquisition over recorded fair value is referred to as the accretable yield and is the interest component of expected cash flow. The accretable yield is recognized into income over the remaining life of the loan if the timing and/or amount of cash flows expected to be collected can be reasonably estimated (the accretion method). If the timing or amount of cash flows expected to be collected cannot be reasonably estimated, the cost recovery method of income recognition is used. The difference between the loan’s total scheduled principal and interest payments over all cash flows expected to be collected at acquisition, considering the impact of prepayments, is referred to as the non-accretable difference. The non-accretable difference represents contractually required principal and interest payments which WesBanco does not expect to collect. Over the life of the loan, management continues to estimate cash flows expected to be collected for ASC 310-30 loans. Decreases in expected cash flows are recognized as impairments through a charge to the provision for loan losses resulting in an increase in the allowance for loan losses. Subsequent improvements in cash flows result in first, reversal of existing valuation allowances recognized subsequent to acquisition, if any, and next, an increase in the amount of accretable yield to be subsequently recognized in interest income on a prospective basis over the loan’s remaining life. Acquired loans that were not individually determined to be purchased with deteriorated credit quality are accounted for in accordance with ASC 310-20, Nonrefundable Fees and Other Costs (ASC 310-20), whereby the premium or discount derived from the fair market value adjustment, on a loan-by-loan or pooled basis, is recognized into interest income on a level yield basis over the remaining expected life of the loan or pool.
Allowance for Credit Losses	Allowance for Credit Losses— The evaluation includes an assessment of quantitative factors such as actual loss experience within each category of loans and testing of certain commercial loans for impairment. The evaluation also considers qualitative factors such as economic trends and conditions, which includes levels of unemployment, real estate values and the impact on specific industries and geographical markets, changes in lending policies and underwriting standards, delinquency and other credit quality trends, concentrations of credit risk, if any, the results of internal loan reviews and examinations by bank regulatory agencies, the volatility of historical loss rates and the velocity of changes in historical loss rates pertaining to the allowance for credit losses. Management relies on observable data from internal and external sources to the extent it is available to evaluate each of these factors and adjusts the actual historical loss rates to reflect the impact these factors may have on probable losses in the portfolio. Commercial real estate and commercial and industrial loans greater than $1 million that are reported as non-accrual or as a troubled debt restructuring are tested individually for impairment. Specific reserves are established when appropriate for such loans based on the present value of expected future cash flows of the loan or the estimated realizable value of the collateral, if any. General reserves are established for loans that are not individually tested for impairment based on historical loss rates adjusted for the impact of the qualitative factors discussed above. Historical loss rates for commercial real estate and commercial and industrial loans are determined for each internal risk grade or group of pass grades using a migration analysis. Residential real estate, home equity and consumer loans are not risk graded, so historical loss rates are utilized to determine the total of each category of loans. Historical loss rates for deposit account overdrafts are based on actual losses in relation to average overdrafts for the period. Management may also adjust its assumptions to account for differences between estimated and actual incurred losses from period to period. The variability of management’s assumptions could alter the level of the allowance for credit losses and may have a material impact on future results of operations and financial condition. The loss estimation models and methods used to determine the allowance for credit losses are continually refined and enhanced; however, there have been no material substantive changes compared to prior periods.
Premises and Equipment	Premises and Equipment—
Other Real Estate Owned and Repossessed Assets	Other Real Estate Owned and Repossessed Assets—
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets— Goodwill is not amortized but is evaluated for impairment annually, or more often if events or circumstances indicate it may be impaired. Finite-lived intangible assets, which consist primarily of core deposit and customer list intangibles (long-term customer-relationship intangible assets) are amortized using straight-line and accelerated methods over their weighted-average estimated useful lives, ranging from ten to sixteen years in total, and are tested for impairment whenever events or circumstances indicate that their carrying amount may not be recoverable. Non-compete agreements are recognized in other assets on the balance sheet and are amortized on a straight-line basis over the life of the respective agreements, ranging from one to four years. Goodwill is evaluated for impairment by either assessing qualitative factors to determine whether it is necessary to perform the goodwill impairment test, or WesBanco may elect to perform the goodwill impairment test. Under the qualitative assessment, WesBanco assesses qualitative factors to determine whether it is more likely than not that the fair value of its reporting units are less than their carrying amounts, including goodwill. If it is more likely than not, the goodwill impairment test is used to identify potential goodwill impairment and measure the amount of a goodwill impairment loss to be recognized, if any. The estimated fair value of each reporting unit is compared to its carrying value, including goodwill. If the estimated fair value of a reporting unit exceeds its carrying amount, the goodwill of that reporting unit is not considered impaired, and no impairment loss is recognized. However, if the carrying amount of the reporting unit exceeds its fair value, an impairment loss is recognized based on the excess of a reporting unit’s carrying value over its fair value. Intangible assets with finite useful lives are evaluated for impairment whenever events or changes in circumstances indicate that their carrying amount may not be recoverable. An impairment loss is recognized when the carrying amount of an intangible asset with a finite useful life is not recoverable from its undiscounted cash flows and is measured as the difference between the carrying amount and the fair value of the asset. WesBanco does not have any indefinite-lived intangible assets.
Bank-Owned Life Insurance	Bank-Owned Life Insurance—
Interest Rate Lock Commitments	Interest Rate Lock Commitments— A mortgage loan sold on a mandatory basis is sold to the secondary market when the mortgage loan is funded. WesBanco enters into TBA contracts in order to control interest rate risk during the period between the IRLC and the sale of the mortgage loan. The IRLC is executed between the mortgagee and WesBanco, and the forward TBA contract is executed between WesBanco and a counterparty. Both the IRLC and the forward TBA contract is considered a derivative. Both types of derivatives are recorded at fair value and are not designated in a qualified hedged accounting program. The changes in fair value are recorded in current earnings within mortgage banking income in the Consolidated Statements of Income. The fair value of IRLC is the gain or loss that would be realized on the underlying loans assuming exercise of the commitments under current market rates versus the rate incorporated in the commitments, taking into consideration fallout. The fair value of forward TBA contracts is based on quoted market prices. Since loans typically close before receipt of funding from an investor, they are accounted for at fair value as “Loans Held for Sale” in the Consolidated Balance Sheets. A mortgage loan sold on a best efforts basis is locked into a forward sales contract on the same day as the IRLC to control interest rate risk during the period between the IRLC and the sale of the mortgage loan. The IRLC is executed between the mortgagee and WesBanco, and the forward sales contract is executed between WesBanco and a counterparty. Both the IRLC and the forward sales contract are considered a derivative. Both types of derivatives are recorded at fair value and are not designated in a qualified hedged accounting program. The changes in fair value are recorded in current earnings within mortgage banking income in the Consolidated Statements of Income. The fair value of IRLC is the gain or loss that would be realized on the underlying loans assuming exercise of the commitments under current market rates versus the rate incorporated in the commitments, taking into consideration fallout. The fair value of forward sales contracts is based on quoted market prices. Since loans typically close before receipt of funding from an investor, they are accounted for at fair value as “Loans Held for Sale” in the Consolidated Balance Sheets.
Derivative Instruments and Hedging Activities	Derivative Instruments and Hedging Activities—
Income Taxes	Income Taxes—
Fair Value	Fair Value— Level 1—Quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; Level 2—Quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, or model-based valuation techniques where all significant assumptions are observable, either directly or indirectly, in the market; Level 3—Valuation is generated from model-based techniques where one or more significant assumptions are not observable, either directly or indirectly, in the market. These unobservable assumptions reflect our own estimates of assumptions that market participants would use in pricing the asset or liability. Valuation techniques may include use of discounted cash flow models and similar techniques. A financial instrument’s level within the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement.
Earnings Per Common Share	Earnings Per Common Share—
Trust Assets	Trust Assets—
Stock-Based Compensation	Stock-Based Compensation—
Defined Benefit Pension Plan	Defined Benefit Pension Plan
Recent accounting pronouncements	Recent accounting pronouncements— In August 2017, the FASB issued ASU No. 2017-12, Targeted Improvements to Accounting for Hedging Activities.” The new guidance will make more financial and nonfinancial hedging strategies eligible for hedge accounting. It also amends the presentation and disclosure requirements and changes how companies assess effectiveness. It is intended to more closely align hedge accounting with companies’ risk management strategies, simplify the application of hedge accounting, and increase transparency as to the scope and results of hedging programs. The guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption is permitted, including adoption in an interim period. WesBanco is assessing the impact of ASU 2017-12 and does not expect it to have a material impact on WesBanco’s Consolidated Financial Statements. In May 2017, the FASB issued ASU No. 2017-09 that provides guidance on determining which changes to the terms and conditions of share-based payment awards require an entity to apply modification accounting under Topic 718. The guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017. Early adoption is permitted, including adoption in an interim period. The amendments should be applied on a prospective basis to an award modified on or after the adoption date. The adoption of this pronouncement did not have a material impact on WesBanco’s Consolidated Financial Statements. In March 2017, FASB issued ASU 2017-08 that shortens the amortization period of certain callable debt securities held at a premium. The premium is required to be amortized to the earliest call date. Securities held at a discount continue to be amortized to maturity. Public business entities must apply the new requirements for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, which for WesBanco will be effective for the fiscal year beginning January 1, 2019. Early adoption is permitted. The adoption of this pronouncement did not have a material impact on WesBanco’s Consolidated Financial Statements. In March 2017, the FASB issued ASU 2017-07 that changes how an employer presents the net periodic benefit cost in the income statement for an employer-sponsored defined benefit pension and/or other postretirement benefit plans. Employers will present the service cost component of net periodic benefit cost in the same income statement line item as other employee compensation costs arising from services rendered during the period. Only the service cost component will be eligible for capitalization in assets. Employers will present the other components of the net periodic benefit cost separately from the line items that includes the service cost outside of any subtotal of operating income, if one is presented. These components will not be eligible for capitalization in assets. For public business entities, the amendments in this update are effective for annual reporting periods beginning after December 15, 2017, including interim reporting periods within those annual reporting periods. Early adoption is permitted as of the beginning of an annual period (i.e., only in the first interim period). For WesBanco, this update will be effective for the fiscal year beginning January 1, 2018. Upon adoption, WesBanco will reclassify the service cost component from employee benefits to salaries and wages, which are both components of non-interest expense. The service cost component for the twelve months ending December 31, 2017 was $2.6 million. In January 2017, the FASB issued ASU 2017-04 that eliminated the requirement to calculate the implied fair value of goodwill to measure a goodwill impairment charge. Instead, entities will record an impairment charge based on the excess of a reporting unit’s carrying amount over its fair value. Public business entities that are a U.S. Securities and Exchange Commission (“SEC”) filer should adopt this update for its annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019, which for WesBanco will be effective for the fiscal year beginning January 1, 2020. Early adoption is permitted. The adoption of this pronouncement did not have a material impact on WesBanco’s Consolidated Financial Statements. In January 2017, the FASB issued ASU No. 2017-01, which clarifies the definition of a business with the objective of adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. ASU 2017-01 will be effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017, which for WesBanco will be effective for the fiscal year beginning January 1, 2018. WesBanco is currently evaluating the potential impact of ASU 2017-01 but it is not expected that the adoption of this new standard will have a material impact on WesBanco’s Consolidated Financial Statements. In October 2016, the FASB issued ASU 2016-16 that provides the recognition of income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. Current guidance prohibits the recognition of current and deferred income taxes for an intra-entity asset transfer until the asset has been sold to an outside party. This prohibition on recognition is an exception to the principle of comprehensive recognition of current and deferred income taxes in generally accepted accounting principles. The exception has led to diversity in practice and is a source of complexity in financial reporting. FASB decided that an entity should recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. Consequently, the amendments in this update eliminate the exception for an intra-entity transfer of an asset other than inventory. The amendments in this update do not include new disclosure requirements; however, existing disclosure requirements might be applicable when accounting for the current and deferred income taxes for an intra-entity transfer of an asset other than inventory. For public business entities, the amendments in this update are effective for annual reporting periods beginning after December 15, 2017, including interim reporting periods within those annual reporting periods, which for WesBanco will be effective for the fiscal year beginning January 1, 2018. The amendments in this update should be applied on a modified retrospective basis through a cumulative-effect adjustment directly to retained earnings as of the beginning of the period of adoption. The adoption of this pronouncement is not expected to have a material impact on WesBanco’s Consolidated Financial Statements. In August 2016, the FASB issued ASU 2016-15 that provides guidance for the classification of cash flows related to (1) debt prepayment or extinguishment costs, (2) settlement of zero-coupon debt instruments or other debt instruments with coupon rates that are insignificant in relation to the effective interest rate on the borrowing, (3) contingent consideration payments made after a business combination, (4) proceeds from the settlement of insurance claims, (5) proceeds from the settlement of corporate-owned life insurance policies, (6) distributions received from equity method investees, (7) beneficial interests in securitization transactions and (8) separately identifiable cash flows and application of the predominance principle. Public business entities must apply the new requirements for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years, which for WesBanco will be effective for the fiscal year beginning January 1, 2018. Early adoption is permitted. The adoption of this pronouncement is not expected to have a material impact on WesBanco’s Consolidated Financial Statements. In June 2016, the FASB issued ASU 2016-13 that will require entities to use a new forward-looking “expected loss” model on trade and other receivables, held-to-maturity debt securities, loans and other instruments that generally will result in the earlier recognition of allowances for credit losses. For available-for-sale debt securities with unrealized losses, entities will measure credit losses in a manner similar to what they do today, except that the losses will be recognized as allowances rather than reductions in the amortized cost of the securities. Entities will have to disclose significantly more information, including information they use to track credit quality by year of origination for most financing receivables. Public business entities must apply the new requirements for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years, which for WesBanco will be effective for the fiscal year beginning January 1, 2020. Early adoption is permitted for fiscal years beginning after December 15, 2018. WesBanco is currently evaluating the impact of the adoption of this pronouncement on WesBanco’s Consolidated Financial Statements. In March 2016, the FASB issued ASU 2016-09 that will require all excess income tax benefits or tax deficiencies of stock awards to be recognized in the income statement when the awards vest or are settled. It also will allow an employer to repurchase more of an employee’s shares than it can today for tax withholding purposes without triggering liability accounting and to make a policy election to account for forfeitures as they occur. Public business entities must apply the new requirements for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. WesBanco made a policy election to account for forfeitures as they occur rather than estimating them over the life of the award. The adoption of this pronouncement did not have a material impact on WesBanco’s Consolidated Financial Statements. In March 2016, the FASB issued ASU 2016-07 that eliminates the requirement to retrospectively apply the equity method in previous periods when an investor initially obtains significant influence over an investee. The update is effective for interim and annual reporting periods in fiscal years beginning after December 15, 2016, and requires prospective adoption. Early adoption is permitted. The adoption of this pronouncement did not have a material impact on WesBanco’s Consolidated Financial Statements. In February 2016, the FASB issued ASU 2016-02 that will require entities to recognize lease assets and lease liabilities on the balance sheet and disclose key information about leasing arrangements. The principal difference from previous guidance is that the lease assets and lease liabilities arising from operating leases were not previously recognized in the balance sheet. Public business entities must apply the new requirements for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted. While we are currently assessing the impact of the adoption of this pronouncement, we expect the primary impact to our consolidated financial position upon adoption will be the recognition, on a discounted basis, of our minimum commitments under non-cancellable operating leases on our consolidated Balance Sheets resulting in the recording of right of use assets and lease obligations. Our current minimum commitments under non-cancellable operating leases are disclosed in Note 6, “Premises and Equipment”. In January 2016, the FASB issued ASU 2016-01 that will require entities to measure equity investments that do not result in consolidation and are not accounted for under the equity method at fair value and recognize any changes in fair value in net income unless the investments qualify for the new practicability exception. The standard does not change the guidance for classifying and measuring investments in debt securities and loans. Entities will have to record changes in instrument-specific credit risk for financial liabilities measured under the fair value option in other comprehensive income. Public business entities must apply the new requirements for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. Early adoption is permitted. The adoption of this pronouncement is not expected to have a material impact on WesBanco’s Consolidated Financial Statements. In May 2014, the FASB issued ASU 2014-09 related to the recognition of revenue from contracts with customers. The new revenue pronouncement creates a single source of revenue guidance for all companies in all industries and is more principles-based than current revenue guidance. The pronouncement provides a five-step model for a company to recognize revenue when it transfers control of goods or services to customers at an amount that reflects the consideration to which it expects to be entitled in exchange for those goods or services. The five steps are, (1) identify the contract with the customer, (2) identify the separate performance obligations in the contract, (3) determine the transaction price, (4) allocate the transaction price to the separate performance obligations and (5) recognize revenue when each performance obligation is satisfied. On July 9, 2015, the FASB approved a one-year deferral of the effective date of the update. The update is effective for interim and annual reporting periods in fiscal years beginning after December 15, 2017. Early adoption is now permitted as of the original effective date for interim and annual reporting periods in fiscal years beginning after December 15, 2016. In March 2016, the FASB issued ASU 2016-08, which amends the principle versus agent guidance in the revenue standard. In April 2016, the FASB issued ASU 2016-10, which clarifies when promised goods or services are separately identifiable in the revenue standard. In May 2016, FASB issued ASU 2016-12, which provides narrow-scope improvements and practical expedients to the revenue standard. WesBanco has completed the evaluation of the impact of this standard on individual customer contracts and determined this standard will not have a material impact on its Consolidated Financial Statements because revenue related to financial instruments, including loans and investment securities are not in scope of these updates. Loan interest income, investment interest income, insurance services revenue and bank-owned life insurance are accounted for under other U.S. GAAP standards and are therefore, out of scope of the ASC 606 revenue standard. Trust fees, service charges on deposits, electronic banking fees, net securities brokerage revenue, net gains on sales of mortgage loans, and net gain on other real estate owned and other assets are in scope of the ASC 606 revenue standard. Management has completed evaluating revenue contracts, as well as identifying WesBanco’s customers, performance obligations and material revenue streams. For the Company’s revenue streams, no material changes have been identified as to the timing of revenue recognition. The Company plans to adopt the revenue recognition standard under the modified retrospective approach as of January 1, 2018. In January 2014, the FASB issued ASU No. 2014-01, which applies to all reporting entities that invest in qualified affordable housing projects through limited liability entities. The pronouncement permits reporting entities to make an accounting policy election to account for these investments using the proportional amortization method if certain conditions exist. The pronouncement also requires disclosure that enables users of its financial statements to understand the nature of these investments in proportion to the tax credits and other tax benefits received and recognizes the net investment performance in the income statement as a component of income tax expense (benefit). The pronouncement is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2014. WesBanco made an accounting policy election to adopt the ASU in the first quarter of 2017. With the adoption of this pronouncement, WesBanco now classifies the amortization of the investment as a component of income tax expense (benefit). The amount for the three and twelve months ending December 31, 2017 was $0.3 million and $1.5 million, respectively, which is included in income tax expense within WesBanco’s Consolidated Financial Statements.

Mergers and Acquisitions (Table

Mergers and Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2017
Allocation of Purchase Price of Assets Acquired and Liabilities Assumed	The following table presents the allocation of the purchase price of the assets acquired and the liabilities assumed at the date of acquisition. (in thousands) September 9, 2016 Assets acquired Cash and due from banks $ 48,212 Securities 173,223 Loans 1,012,410 Goodwill and other intangible assets 104,990 Accrued income and other assets (1) 212,550 Total assets acquired $ 1,551,385 Liabilities assumed Deposits $ 1,193,010 Borrowings 123,001 Accrued expenses and other liabilities 14,876 Total liabilities assumed 1,330,887 Net assets acquired $ 220,498 (1) Includes receivables of $105.8 million from the sale of available-for-sale securities prior to the acquisition date.
Your Community Bankshares, Inc [Member]
Summary of Purchase Price of Acquisition and Resulting Goodwill	The final purchase price of the YCB acquisition and resulting goodwill is summarized as follows: (in thousands) September 9, 2016 Purchase Price: Fair value of WesBanco shares issued $ 177,149 Cash consideration for outstanding YCB shares 43,349 Total purchase price $ 220,498 Fair value of: Tangible assets acquired $ 1,398,183 Core deposit and other intangible assets acquired 11,957 Liabilities assumed (1,330,887 ) Net cash received in the acquisition 48,212 Fair value of net assets acquired $ 127,465 Goodwill recognized $ 93,033
Purchase Price Allocation Adjustment [Member]
Allocation of Purchase Price of Assets Acquired and Liabilities Assumed	The following table presents the changes in the allocation of the purchase price of the assets acquired and the liabilities assumed at the date of the acquisition previously reported as of December 31, 2016: (in thousands) September 9, 2016 Goodwill recognized as of December 31, 2016 $ 92,889 Change in fair value of net assets acquired: Assets Loans (1,156 ) Accrued income and other assets 743 Liabilities Borrowings — Accrued expenses and other liabilities 269 Fair value of net assets acquired $ (144 ) Increase in goodwill recognized 144 Goodwill recognized as of December 31, 2017 $ 93,033

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Summary of Earnings Per Common Share	Earnings per common share are calculated as follows: For the years ended December 31, (in thousands, except shares and per share amounts) 2017 2016 2015 Numerator for both basic and diluted earnings per common share: Net income $ 94,482 $ 86,635 $ 80,762 Denominator: Total average basic common shares outstanding 44,003,208 40,100,320 37,488,331 Effect of dilutive stock options and other stock compensation 72,085 26,756 58,796 Total diluted average common shares outstanding 44,075,293 40,127,076 37,547,127 Earnings per common share—basic $ 2.15 $ 2.16 $ 2.15 Earnings per common share—diluted 2.14 2.16 2.15

Securities (Tables)

Securities (Tables)	12 Months Ended
	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Schedule of Amortized Cost and Fair Value of Available-for-sale and Held-to-maturity Securities	The following table shows the amortized cost and fair values of available-for-sale and held-to-maturity securities: December 31, 2017 December 31, 2016 (in thousands) Amortized Gross Gross Estimated Amortized Gross Gross Estimated Available-for-sale U.S. Government sponsored entities and agencies $ 72,425 $ 24 $ (606 ) $ 71,843 $ 54,803 $ 3 $ (763 ) $ 54,043 Residential mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 954,115 214 (19,407 ) 934,922 953,475 884 (16,070 ) 938,289 Commercial mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 116,448 4 (1,585 ) 114,867 98,922 27 (2,139 ) 96,810 Obligations of states and political subdivisions 102,363 2,927 (460 ) 104,830 110,208 3,114 (1,659 ) 111,663 Corporate debt securities 35,234 228 (59 ) 35,403 35,292 117 (108 ) 35,301 Total debt securities $ 1,280,585 $ 3,397 $ (22,117 ) $ 1,261,865 $ 1,252,700 $ 4,145 $ (20,739 ) $ 1,236,106 Equity securities 4,223 1,390 — 5,613 4,062 1,032 (24 ) 5,070 Total available-for-sale securities $ 1,284,808 $ 4,787 $ (22,117 ) $ 1,267,478 $ 1,256,762 $ 5,177 $ (20,763 ) $ 1,241,176 Held-to-maturity U.S. Government sponsored entities and agencies $ 11,465 $ — $ (325 ) $ 11,140 $ 13,394 $ — $ (414 ) $ 12,980 Residential mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 170,025 544 (2,609 ) 167,960 215,141 1,279 (2,563 ) 213,857 Obligations of states and political subdivisions 794,655 17,364 (1,609 ) 810,410 805,019 15,652 (5,529 ) 815,142 Corporate debt securities 33,355 919 — 34,274 34,413 418 (20 ) 34,811 Total held-to-maturity securities $ 1,009,500 $ 18,827 $ (4,543 ) $ 1,023,784 $ 1,067,967 $ 17,349 $ (8,526 ) $ 1,076,790 Total $ 2,294,308 $ 23,614 $ (26,660 ) $ 2,291,262 $ 2,324,729 $ 22,526 $ (29,289 ) $ 2,317,966
Schedule of Fair Value of Available-for-sale and Held-to-maturity Securities by Contractual Maturity	The following table presents the fair value of available-for-sale and held-to-maturity securities by contractual maturity at December 31, 2017. In many instances, the issuers may have the right to call or prepay obligations without penalty prior to the contractual maturity date. December 31, 2017 (in thousands) One Year One to Five to After Ten Mortgage-backed Total Available-for-sale U.S. Government sponsored entities and agencies $ 9,938 $ 1,990 $ 16,837 $ 6,888 $ 36,190 $ 71,843 Residential mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies (1) — — — — 934,922 934,922 Commercial mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies (1) — — — — 114,867 114,867 Obligations of states and political subdivisions 3,964 18,827 39,020 43,019 — 104,830 Corporate debt securities 3,990 26,431 4,982 — — 35,403 Equity securities (2) — — — — 5,613 5,613 Total available-for-sale securities $ 17,892 $ 47,248 $ 60,839 $ 49,907 $ 1,091,592 $ 1,267,478 Held-to-maturity (3) U.S. Government sponsored entities and agencies $ — $ — $ — $ — $ 11,140 $ 11,140 Residential mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies (1) — — — — 167,960 167,960 Obligations of states and political subdivisions 4,855 106,502 406,338 292,715 — 810,410 Corporate debt securities — 7,721 26,553 — — 34,274 Total held-to-maturity securities $ 4,855 $ 114,223 $ 432,891 $ 292,715 $ 179,100 $ 1,023,784 Total $ 22,747 $ 161,471 $ 493,730 $ 342,622 $ 1,270,692 $ 2,291,262 (1) Mortgage-backed and collateralized mortgage securities, which have prepayment provisions, are not assigned to maturity categories due to fluctuations in their prepayment speeds. (2) Equity securities, which have no stated maturity, are not assigned a maturity category. (3) The held-to-maturity portfolio is carried at an amortized cost of $1.0 billion.
Schedule of Gross Realized Gains and Losses on the Sales and Calls of Securities	The following table presents the gross realized gains and losses on sales and calls of available-for-sale and held-to-maturity securities for the years ended December 31, 2017, 2016 and 2015, respectively. For the Years Ended (in thousands) 2017 2016 2015 Gross realized gains $ 675 $ 2,638 $ 1,029 Gross realized losses (108 ) (281 ) (81 ) Net realized gains $ 567 $ 2,357 $ 948
Schedule of Unrealized Losses on Investment Securities	The following tables provide information on unrealized losses on investment securities that have been in an unrealized loss position for less than twelve months and twelve months or more as of December 31, 2017 and 2016: December 31, 2017 Less than 12 months 12 months or more Total (dollars in thousands) Fair Unrealized # of Fair Unrealized # of Fair Unrealized # of U.S. Government sponsored entities and agencies $ 24,776 $ (160 ) 4 $ 42,248 $ (771 ) 8 $ 67,024 $ (931 ) 12 Residential mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 423,794 (5,039 ) 87 637,461 (16,977 ) 193 1,061,255 (22,016 ) 280 Commercial mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 79,061 (1,089 ) 10 27,852 (496 ) 6 106,913 (1,585 ) 16 Obligations of states and political subdivisions 132,831 (852 ) 210 77,554 (1,217 ) 160 210,385 (2,069 ) 370 Corporate debt securities 4,015 (19 ) 1 1,948 (40 ) 1 5,963 (59 ) 2 Equity securities — — — — — — — — — Total temporarily impaired securities $ 664,477 $ (7,159 ) 312 $ 787,063 $ (19,501 ) 368 $ 1,451,540 $ (26,660 ) 680 December 31, 2016 Less than 12 months 12 months or more Total (dollars in thousands) Fair Unrealized # of Fair Unrealized # of Fair Unrealized # of U.S. Government sponsored entities and agencies $ 58,108 $ (1,177) 11 $ — $ — — $ 58,108 $ (1,177) 11 Residential mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 969,174 (16,436 ) 232 58,839 (2,197 ) 14 1,028,013 (18,633 ) 246 Commercial mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 88,169 (2,122 ) 14 679 (17 ) 2 88,848 (2,139 ) 16 Obligations of states and political subdivisions 364,583 (7,121 ) 604 2,047 (67 ) 3 366,630 (7,188 ) 607 Corporate debt securities 10,011 (78 ) 3 5,973 (50 ) 2 15,984 (128 ) 5 Equity securities 2,938 (24 ) 2 — — — 2,938 (24 ) 2 Total temporarily impaired securities $ 1,492,983 $ (26,958 ) 866 $ 67,538 $ (2,331 ) 21 $ 1,560,521 $ (29,289 ) 887

Loans and the Allowance for C37

Loans and the Allowance for Credit Losses (Tables)	12 Months Ended
	Dec. 31, 2017
Receivables [Abstract]
Schedule of Recorded Investment in Loans by Category	The recorded investment in loans is presented in the Consolidated Balance Sheets net of deferred loan fees and costs, and discounts on purchased loans. The deferred loan (costs) and fees were $(1.6) million and $0.3 million at December 31, 2017 and 2016, respectively. The unamortized discount on purchased loans from acquisitions was $21.9 million, including $10.5 million related to YCB, and $24.1 million at December 31, 2017 and 2016, respectively. December 31, December 31, (in thousands) 2017 2016 Commercial real estate: Land and construction $ 392,597 $ 496,539 Improved property 2,601,851 2,376,972 Total commercial real estate 2,994,448 2,873,511 Commercial and industrial 1,125,327 1,088,118 Residential real estate 1,353,301 1,383,390 Home equity 529,196 508,359 Consumer 339,169 396,058 Total portfolio loans 6,341,441 6,249,436 Loans held for sale 20,320 17,315 Total loans $ 6,361,761 $ 6,266,751
Summary of Changes in Allowance for Credit Losses	The following tables summarize changes in the allowance for credit losses applicable to each category of the loan portfolio: For the Year Ended December 31, 2017 (in thousands) Commercial Commercial Real Estate- Property Commercial Residential Home Consumer Deposit Total Balance at beginning of year: Allowance for loan losses $ 4,348 $ 18,628 $ 8,412 $ 4,106 $ 3,422 $ 3,998 $ 760 $ 43,674 Allowance for loan commitments 151 17 188 9 162 44 — 571 Total beginning allowance for credit losses 4,499 18,645 8,600 4,115 3,584 4,042 760 44,245 Provision for credit losses: Provision for loan losses (1,259 ) 4,386 2,733 (175 ) 2,066 1,231 1,001 9,983 Provision for loan commitments (32 ) 9 (15 ) (2 ) 50 (7 ) — 3 Total provision for credit losses (1,291 ) 4,395 2,718 (177 ) 2,116 1,224 1,001 9,986 Charge-offs (72 ) (2,381 ) (2,669 ) (1,064 ) (1,221 ) (3,989 ) (1,293 ) (12,689 ) Recoveries 100 533 938 339 230 1,823 353 4,316 Net charge-offs 28 (1,848 ) (1,731 ) (725 ) (991 ) (2,166 ) (940 ) (8,373 ) Balance at end of period: Allowance for loan losses 3,117 21,166 9,414 3,206 4,497 3,063 821 45,284 Allowance for loan commitments 119 26 173 7 212 37 — 574 Total ending allowance for credit losses $ 3,236 $ 21,192 $ 9,587 $ 3,213 $ 4,709 $ 3,100 $ 821 $ 45,858 For the Year Ended December 31, 2016 (in thousands) Commercial Commercial Commercial Residential Home Consumer Deposit Total Balance at beginning of year: Allowance for loan losses $ 4,390 $ 14,748 $ 10,002 $ 4,582 $ 2,883 $ 4,763 $ 342 $ 41,710 Allowance for loan commitments 157 26 260 7 117 46 — 613 Total beginning allowance for credit losses 4,547 14,774 10,262 4,589 3,000 4,809 342 42,323 Provision for credit losses: Provision for loan losses 26 4,223 1,160 16 662 1,356 1,077 8,520 Provision for loan commitments (6 ) (9 ) (72 ) 2 45 (2 ) — (42 ) Total provision for credit losses 20 4,214 1,088 18 707 1,354 1,077 8,478 Charge-offs (73 ) (1,886 ) (3,070 ) (937 ) (397 ) (3,606 ) (884 ) (10,853 ) Recoveries 5 1,543 320 445 274 1,485 225 4,297 Net charge-offs (68 ) (343 ) (2,750 ) (492 ) (123 ) (2,121 ) (659 ) (6,556 ) Balance at end of period: Allowance for loan losses 4,348 18,628 8,412 4,106 3,422 3,998 760 43,674 Allowance for loan commitments 151 17 188 9 162 44 — 571 Total ending allowance for credit losses $ 4,499 $ 18,645 $ 8,600 $ 4,115 $ 3,584 $ 4,042 $ 760 $ 44,245 For the Year Ended December 31, 2015 (in thousands) Commercial Commercial Commercial Residential Home Consumer Deposit Total Balance at beginning of year: Allowance for loan losses $ 5,654 $ 17,573 $ 9,063 $ 5,382 $ 2,329 $ 4,078 $ 575 $ 44,654 Allowance for loan commitments 194 10 112 9 90 40 — 455 Total beginning allowance for credit losses 5,848 17,583 9,175 5,391 2,419 4,118 575 45,109 Provision for credit losses: Provision for loan losses (1,265 ) 1,250 3,289 399 1,794 2,337 391 8,195 Provision for loan commitments (37 ) 16 148 (2 ) 27 6 — 158 Total provision for credit losses (1,302 ) 1,266 3,437 397 1,821 2,343 391 8,353 Charge-offs — (4,915 ) (2,785 ) (1,803 ) (1,502 ) (2,892 ) (846 ) (14,743 ) Recoveries 1 840 435 604 262 1,240 222 3,604 Net charge-offs 1 (4,075 ) (2,350 ) (1,199 ) (1,240 ) (1,652 ) (624 ) (11,139 ) Balance at end of period: Allowance for loan losses 4,390 14,748 10,002 4,582 2,883 4,763 342 41,710 Allowance for loan commitments 157 26 260 7 117 46 — 613 Total ending allowance for credit losses $ 4,547 $ 14,774 $ 10,262 $ 4,589 $ 3,000 $ 4,809 $ 342 $ 42,323
Allowance for Credit Losses and Recorded Investments in Loans	The following tables present the allowance for credit losses and recorded investments in loans by category: Allowance for Credit Losses and Recorded Investment in Loans (in thousands) Commercial Commercial Commercial Residential Home Consumer Deposit Total December 31, 2017 Allowance for credit losses: Allowance for loans individually evaluated for impairment $ — $ 388 $ — $ — $ — $ — $ — $ 388 Allowance for loans collectively evaluated for impairment 3,117 20,778 9,414 3,206 4,497 3,063 821 44,896 Allowance for loan commitments 119 26 173 7 212 37 — 574 Total allowance for credit losses $ 3,236 $ 21,192 $ 9,587 $ 3,213 $ 4,709 $ 3,100 $ 821 $ 45,858 Portfolio loans: Individually evaluated for impairment (1) $ — $ 3,344 $ — $ — $ — $ — $ — $ 3,344 Collectively evaluated for impairment 391,140 2,593,393 1,124,544 1,352,587 529,196 339,163 — 6,330,023 Acquired with deteriorated credit quality 1,457 5,114 783 714 — 6 — 8,074 Total portfolio loans $ 392,597 $ 2,601,851 $ 1,125,327 $ 1,353,301 $ 529,196 $ 339,169 $ — $ 6,341,441 December 31, 2016 Allowance for credit losses: Allowance for loans individually evaluated for impairment $ — $ 470 $ 407 $ — $ — $ — $ — $ 877 Allowance for loans collectively evaluated for impairment 4,348 18,158 8,005 4,106 3,422 3,998 760 42,797 Allowance for loan commitments 151 17 188 9 162 44 — 571 Total allowance for credit losses $ 4,499 $ 18,645 $ 8,600 $ 4,115 $ 3,584 $ 4,042 $ 760 $ 44,245 Portfolio loans: Individually evaluated for impairment (1) $ — $ 3,012 $ 1,270 $ — $ — $ — $ — $ 4,282 Collectively evaluated for impairment 494,928 2,364,067 1,086,445 1,382,447 508,359 396,049 — 6,232,295 Acquired with deteriorated credit quality 1,611 9,893 403 943 — 9 — 12,859 Total portfolio loans $ 496,539 $ 2,376,972 $ 1,088,118 $ 1,383,390 $ 508,359 $ 396,058 $ — $ 6,249,436 (1) Commercial loans greater than $1 million that are reported as non-accrual or as a TDR are individually evaluated for impairment.
Summary of Commercial Loans by Risk Grade	The following tables summarize commercial loans by their assigned risk grade: Commerical Loans by Internally Assigned Risk Grade (in thousands) Commercial Commercial Commercial Total As of December 31, 2017 Pass $ 386,753 $ 2,548,805 $ 1,110,267 $ 4,045,825 Criticized—compromised 2,984 25,673 7,435 36,092 Classified—substandard 2,860 27,373 7,625 37,858 Classified—doubtful — — — — Total $ 392,597 $ 2,601,851 $ 1,125,327 $ 4,119,775 As of December 31, 2016 Pass $ 489,380 $ 2,324,755 $ 1,072,751 $ 3,886,886 Criticized—compromised 4,405 15,295 5,078 24,778 Classified—substandard 2,754 36,922 10,289 49,965 Classified—doubtful — — — — Total $ 496,539 $ 2,376,972 $ 1,088,118 $ 3,961,629
Summary of Changes in Accretable Yield for Loans Acquired with Deteriorated Credit Quality	The following table provides changes in accretable yield for all loans acquired with deteriorated credit quality: For the Years Ended (in thousands) December 31, December 31, Balance at beginning of period $ 1,717 $ 1,206 Acquisitions — 837 Reduction due to change in projected cash flows — (484 ) Reclass from non-accretable difference 1,719 1,065 Transfers (216 ) (328 ) Accretion (1,496 ) (579 ) Balance at end of period $ 1,724 $ 1,717
Summary of Age Analysis of Loan Categories	The following tables summarize the age analysis of all categories of loans. Age Analysis of Loans (in thousands) Current 30-59 Days 60-89 Days 90 Days Total Total 90 Days As of December 31, 2017 Commercial real estate: Land and construction $ 392,189 $ — $ 172 $ 236 $ 408 $ 392,597 $ — Improved property 2,589,704 374 1,200 10,573 12,147 2,601,851 243 Total commercial real estate 2,981,893 374 1,372 10,809 12,555 2,994,448 243 Commercial and industrial 1,121,957 572 196 2,602 3,370 1,125,327 20 Residential real estate 1,338,240 4,487 2,376 8,198 15,061 1,353,301 1,113 Home equity 522,584 2,135 683 3,794 6,612 529,196 742 Consumer 334,723 2,466 842 1,138 4,446 339,169 608 Total portfolio loans 6,299,397 10,034 5,469 26,541 42,044 6,341,441 2,726 Loans held for sale 20,320 — — — — 20,320 — Total loans $ 6,319,717 $ 10,034 $ 5,469 $ 26,541 $ 42,044 $ 6,361,761 $ 2,726 Impaired loans included above are as follows: Non-accrual loans $ 9,195 $ 1,782 $ 2,033 $ 23,815 27,630 $ 36,825 TDRs accruing interest (1) 6,055 348 168 — 516 6,571 Total impaired $ 15,250 $ 2,130 $ 2,201 $ 23,815 $ 28,146 $ 43,396 As of December 31, 2016 Commercial real estate: Land and construction $ 496,245 $ — $ — $ 294 $ 294 $ 496,539 $ — Improved property 2,367,790 1,154 363 7,665 9,182 2,376,972 318 Total commercial real estate 2,864,035 1,154 363 7,959 9,476 2,873,511 318 Commercial and industrial 1,082,390 2,508 1,011 2,209 5,728 1,088,118 229 Residential real estate 1,365,956 6,701 1,043 9,690 17,434 1,383,390 1,922 Home equity 502,087 2,358 862 3,052 6,272 508,359 626 Consumer 390,354 3,674 1,149 881 5,704 396,058 644 Total portfolio loans 6,204,822 16,395 4,428 23,791 44,614 6,249,436 3,739 Loans held for sale 17,315 — — — — 17,315 — Total loans $ 6,222,137 $ 16,395 $ 4,428 $ 23,791 $ 44,614 $ 6,266,751 $ 3,739 Impaired loans included above are as follows: Non-accrual loans $ 7,570 $ 3,479 $ 923 $ 19,812 24,214 $ 31,784 TDRs accruing interest (1) 7,014 342 50 240 632 7,646 Total impaired $ 14,584 $ 3,821 $ 973 $ 20,052 $ 24,846 $ 39,430 (1) Loans 90 days or more past due and accruing interest exclude TDRs 90 days or more past due and accruing interest.
Summary of Impaired Loans	The following tables summarize impaired loans: Impaired Loans December 31, 2017 December 31, 2016 (in thousands) Unpaid Recorded Related Unpaid Recorded Related With no related specific allowance recorded: Commercial real estate: Land and construction $ 412 $ 239 $ — $ 1,212 $ 766 $ — Improved property 18,229 12,863 — 9,826 8,141 — Commercial and industrial 3,745 3,086 — 4,456 3,181 — Residential real estate 20,821 18,982 — 20,152 18,305 — Home equity 5,833 5,169 — 4,589 4,011 — Consumer 1,084 952 — 884 744 — Total impaired loans without a specific allowance 50,124 41,291 — 41,119 35,148 — With a specific allowance recorded: Commercial real estate: Land and construction — — — — — — Improved property 2,105 2,105 388 3,012 3,012 470 Commercial and industrial — — — 4,875 1,270 407 Total impaired loans with a specific allowance 2,105 2,105 388 7,887 4,282 877 Total impaired loans $ 52,229 $ 43,396 $ 388 $ 49,006 $ 39,430 $ 877 (1) The difference between the unpaid principal balance and the recorded investment generally reflects amounts that have been previously charged-off and fair market value adjustments on acquired impaired loans. Impaired Loans For the Year Ended For the Year Ended For the Year Ended (in thousands) Average Interest Average Interest Average Interest With no related specific allowance recorded: Commercial real estate: Land and construction $ 460 $ — $ 993 $ — $ 2,156 $ 41 Improved property 10,790 436 9,128 115 17,192 437 Commercial and industrial 3,577 8 3,188 9 2,979 170 Residential real estate 17,991 252 17,021 308 17,876 862 Home equity 4,599 19 3,502 20 2,924 90 Consumer 787 7 909 8 1,199 105 Total impaired loans without a specific allowance 38,204 722 34,741 460 44,326 1,705 With a specific allowance recorded: Commercial real estate: Land and construction — — — — — — Improved property 4,446 — 3,012 — 5,896 — Commercial and industrial 254 — 3,214 — 3,579 292 Total impaired loans with a specific allowance 4,700 — 6,226 — 9,475 292 Total impaired loans $ 42,904 $ 722 $ 40,967 $ 460 $ 53,801 $ 1,997
Recorded Investment in Non-Accrual Loans and TDRs	The following tables present the recorded investment in non-accrual loans and TDRs: Non-accrual Loans (1) (in thousands) December 31, December 31, Commercial real estate: Land and construction $ 239 $ 766 Improved property 13,318 9,535 Total commercial real estate 13,557 10,301 Commercial and industrial 2,958 4,299 Residential real estate 14,661 12,994 Home equity 4,762 3,538 Consumer 887 652 Total $ 36,825 $ 31,784 (1) At December 31, 2017, there were three borrowers with loans greater than $1.0 million totaling $6.8 million, as compared to two borrowers with loans greater than $1.0 million totaling $4.3 million at December 31, 2016. Total non-accrual loans include loans that are also restructured. Such loans are also set forth in the following table as non-accrual TDRs. TDRs December 31, 2017 December 31, 2016 (in thousands) Accruing Non-Accrual Total Accruing Non-Accrual Total Commercial real estate: Land and construction $ — $ 3 $ 3 $ — $ 8 $ 8 Improved property 1,650 428 2,078 1,618 688 2,306 Total commercial real estate 1,650 431 2,081 1,618 696 2,314 Commercial and industrial 128 97 225 152 151 303 Residential real estate 4,321 1,880 6,201 5,311 2,212 7,523 Home equity 407 337 744 473 297 770 Consumer 65 120 185 92 190 282 Total $ 6,571 $ 2,865 $ 9,436 $ 7,646 $ 3,546 $ 11,192 As of December 31, 2017 and December 31, 2016, there were no TDRs greater than $1.0 million. The concessions granted in the majority of loans reported as accruing and non-accrual TDRs are extensions of the maturity date or the amortization period, reductions in the interest rate below the prevailing market rate for loans with comparable characteristics, and/or permitting interest-only payments for longer than three months. WesBanco had unfunded commitments to debtors whose loans were classified as impaired of $0.1 million and $0 as of December 31, 2017 and 2016, respectively.
Loans Identified as TDRs	The following table presents details related to loans identified as TDRs during the years ended December 31, 2017 and 2016: For the Year Ended December 31, 2017 For the Year Ended December 31, 2016 (dollars in thousands) Number of Pre- Post- Number of Pre- Post- Commercial real estate: Land and construction — $ — $ — — $ — $ — Improved property 2 345 331 — — — Total commercial real estate 2 345 331 — — — Commercial and industrial 1 64 58 2 125 120 Residential real estate 3 144 137 4 178 166 Home equity 2 68 61 1 44 40 Consumer 5 43 30 14 98 74 Total 13 $ 664 $ 617 21 $ 445 $ 400 (1) Excludes loans that were either paid off or charged-off by period end. The pre-modification balance represents the balance outstanding at the beginning of the period. The post-modification balance represents the outstanding balance at period end. The following table summarizes TDRs which defaulted (defined as past due 90 days) during the years ended December 31, 2017 and 2016 that were restructured within the last twelve months prior to December 31, 2017 and 2016: Defaulted TDRs (1) For the Year Ended Defaulted TDRs (1) For the Year Ended (dollars in thousands) Number of Recorded Number of Recorded Commercial real estate: Land and construction — $ — — $ — Improved property — — — — Total commercial real estate — — — — Commercial and industrial — — — — Residential real estate 2 128 — — Home equity 1 7 — — Consumer — — 1 16 Total 3 $ 135 1 $ 16 (1) Excludes loans that were either charged-off or cured by period end. The recorded investment is as of December 31, 2017 and 2016. TDRs that default are placed on non-accrual status unless they are both well-secured and in the process of collection. The loans in the table above were not accruing interest.
Recognition of Interest Income on Impaired Loans	The following table summarizes the recognition of interest income on impaired loans: For the years ended December 31, (in thousands) 2017 2016 2015 Average impaired loans $ 42,904 $ 40,967 $ 53,801 Amount of contractual interest income on impaired loans 3,089 2,747 3,061 Amount of interest income recognized on impaired loans 722 460 1,997
Summary of Other Real Estate Owned and Repossessed Assets	The following table summarizes other real estate owned and repossessed assets included in other assets: December 31, (in thousands) 2017 2016 Other real estate owned $ 5,195 $ 8,206 Repossessed assets 102 140 Total other real estate owned and repossessed assets $ 5,297 $ 8,346

Premises and Equipment (Tables)

Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Schedule of Premises and Equipment	Premises and equipment include: December 31, (in thousands) 2017 2016 Land and improvements $ 41,209 $ 43,059 Buildings and improvements 141,960 136,546 Furniture and equipment 75,816 72,050 Total cost 258,985 251,655 Accumulated depreciation and amortization (128,263 ) (118,358 ) Total premises and equipment, net $ 130,722 $ 133,297
Future Minimum Lease Payments Under Non-cancellable Leases	Future minimum lease payments under non-cancellable leases with initial or remaining lease terms in excess of one year at December 31, 2017 are as follows ( in thousands Year Amount 2018 $ 4,240 2019 3,713 2020 3,548 2021 3,089 2022 2,294 2023 and thereafter 13,690 Total $ 30,574

Goodwill and Other Intangible39

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
WesBanco's Capitalized Other Intangible Assets and Related Accumulated Amortization	The following table shows WesBanco’s capitalized other intangible assets and related accumulated amortization: December 31, (in thousands) 2017 2016 Other intangible assets: Gross carrying amount $ 37,725 $ 37,725 Accumulated amortization (22,407 ) (18,341 ) Net carrying amount of other intangible assets $ 15,318 $ 19,384
Schedule of Future Amortization on Intangible Assets	The following table shows the amortization on WesBanco’s other intangible assets for each of the next five years ( in thousands Year Amount 2018 $ 3,543 2019 3,037 2020 2,564 2021 2,122 2022 1,701

Certificates of Deposit (Tables

Certificates of Deposit (Tables)	12 Months Ended
	Dec. 31, 2017
Banking and Thrift [Abstract]
Schedule of Maturities of Total Certificates of Deposit	At December 31, 2017, the scheduled maturities of total certificates of deposit are as follows (in thousands) Year Amount 2018 $ 736,435 2019 218,392 2020 154,186 2021 83,079 2022 49,564 2023 and thereafter 35,401 Total $ 1,277,057

FHLB and Other Short-Term Bor41

FHLB and Other Short-Term Borrowings (Tables)	12 Months Ended
	Dec. 31, 2017
Text Block [Abstract]
Schedule of Aggregate Annual Maturities and Weighted-Average Interest Rates of FHLB Borrowing	The following table presents the aggregate annual maturities and weighted-average interest rates of FHLB borrowings at December 31, 2017 based on their contractual maturity dates and interest rates (dollars in thousands) Year Scheduled Weighted 2018 $ 540,770 1.40 % 2019 334,104 1.78 % 2020 71,064 1.96 % 2021 294 5.22 % 2022 — 0.00 % 2023 and thereafter 1,971 1.42 % Total $ 948,203 1.57 %

Subordinated Debt and Junior 42

Subordinated Debt and Junior Subordinated Debt (Tables)	12 Months Ended
	Dec. 31, 2017
Text Block [Abstract]
Schedule of Junior Subordinated Debt by Trust	The following table shows WesBanco’s trust subsidiaries with outstanding Trust Preferred Securities as of December 31, 2017: (in thousands) Trust Common Junior Stated Optional WesBanco Capital Trust II (1) $ 13,000 $ 410 $ 13,410 6/30/2033 6/30/2008 WesBanco Capital Statutory Trust III (2) 17,000 526 17,526 6/26/2033 6/26/2008 WesBanco Capital Trust IV (3) 20,000 619 20,619 6/17/2034 6/17/2009 WesBanco Capital Trust V (3) 20,000 619 20,619 6/17/2034 6/17/2009 WesBanco Capital Trust VI (4) 15,000 464 15,464 3/17/2035 3/17/2010 Oak Hill Capital Trust 2 (5) 5,000 155 5,155 10/18/2034 10/18/2009 Oak Hill Capital Trust 3 (6) 8,000 248 8,248 10/18/2034 10/18/2009 Oak Hill Capital Trust 4 (7) 5,000 155 5,155 6/30/2035 6/30/2015 Community Bank Shares Statutory Trust I (3) 6,252 217 6,469 6/17/2034 6/17/2014 Community Bank Shares Statutory Trust II (8) 8,476 310 8,786 6/15/2036 6/15/2016 First Federal Statutory Trust II (9) 8,419 310 8,729 3/22/2037 3/15/2017 First Federal Statutory Trust III (10) 8,144 240 8,384 6/24/2038 6/24/2018 Total $ 134,291 $ 4,273 $ 138,564 (1) Variable rate based on the three-month LIBOR plus 3.15% with a current rate of 4.84% through March 30, 2018, adjustable quarterly. (2) Variable rate based on the three-month LIBOR plus 3.10% with a current rate of 4.77% through March 26, 2018, adjustable quarterly. (3) Variable rate based on the three-month LIBOR plus 2.65% with a current rate of 4.25% through March 17, 2018, adjustable quarterly. (4) Variable rate based on the three-month LIBOR plus 1.77% with a current rate of 3.37% through March 17, 2018, adjustable quarterly. (5) Variable rate based on the three-month LIBOR plus 2.40% with a current rate of 3.75% through January 18, 2018, adjustable quarterly. (6) Variable rate based on the three-month LIBOR plus 2.30% with a current rate of 3.65% through January 18, 2018, adjustable quarterly. (7) Variable rate based on the three-month LIBOR plus 1.60% with a current rate of 3.29% through March 30, 2018, adjustable quarterly. (8) Variable rate based on the three-month LIBOR plus 1.70% with a current rate of 3.29% through March 15, 2018, adjustable quarterly. (9) Variable rate based on the three-month LIBOR plus 1.60% with a current rate of 3.19% through March 15, 2018, adjustable quarterly. (10) Fixed rate of 8.00% through maturity, callable June 24, 2018 and thereafter at par.

Derivatives and Hedging Activ43

Derivatives and Hedging Activities (Tables)	12 Months Ended
	Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Summary of Fair Values of Derivative Instruments on Balance Sheets	The table below presents the fair value of WesBanco’s derivative financial instruments as well as their classification on the Balance Sheet as of December 31, 2017 and December 31, 2016: December 31, 2017 December 31, 2016 (in thousands) Notional or Asset Liability Notional or Asset Liability Derivatives Loan Swaps: Interest rate swaps $ 298,223 $ 7,351 $ 7,345 $ 206,923 $ 5,596 $ 5,199 Other contracts: Interest rate loan commitments 20,319 49 — 19,453 — 123 Best efforts forward delivery commitments 2,905 — 6 19,453 79 — Forward TBA contracts 31,750 — 23 — — — Total derivatives $ 7,400 $ 7,374 $ 5,675 $ 5,322
Summary of Effect of Derivative Instruments on Income Statement	The table below presents the change in the fair value of the Company’s derivative financial instruments reflected within the other non-interest income line item of the consolidated income statement for the years ended December 31, 2017, 2016 and 2015, respectively. For the Years Ended (in thousands) Location of Gain/(Loss) 2017 2016 2015 Interest rate swaps Other income $ (391 ) $ 495 $ 3 Interest rate loan commitments Mortgage banking income 49 (123 ) 15 Best efforts forward sales contracts Mortgage banking income (6 ) 79 5 Forward TBA contracts Mortgage banking income (23 ) — — Total $ (371 ) $ 451 $ 23

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2017
Retirement Benefits [Abstract]
Summary of Benefit Obligations and Funded Status of the Plan	The benefit obligations and funded status of the Plan are as follows: December 31, (dollars in thousands) 2017 2016 Accumulated benefit obligation at end of year $ 119,559 $ 104,775 Change in projected benefit obligation: Projected benefit obligation at beginning of year $ 115,458 $ 109,400 Service cost 2,578 2,799 Interest cost 4,393 5,094 Actuarial (gain) loss 12,172 2,569 Acquisition — 1,392 Benefits paid (4,294 ) (5,796 ) Projected benefit obligation at end of year $ 130,307 $ 115,458 Change in fair value of plan assets: Fair value of plan assets at beginning of year $ 121,597 $ 113,292 Actual return on plan assets 20,119 7,125 Employer contribution 5,000 5,750 Acquisition — 1,226 Benefits paid (4,294 ) (5,796 ) Fair value of plan assets at end of year $ 142,422 $ 121,597 Amounts recognized in the statement of financial position: Funded status $ 12,115 $ 6,139 Net amounts recognized as receivable pension costs in the consolidated balance sheets $ 12,115 $ 6,139 Amounts recognized in accumulated other comprehensive income consist of: Unrecognized prior service cost $ 104 $ 130 Unrecognized net loss 24,336 27,857 Net amounts recognized in accumulated other comprehensive income (before tax) $ 24,440 $ 27,987 Weighted average assumptions used to determine benefit obligations: Discount rate 3.81 % 4.46 % Rate of compensation increase 3.70 % 3.74 % Expected long-term return on assets 6.30 % 6.30 %
Components of and Weighted-Average Assumptions Used in Determining Net Periodic Benefit Costs	The components of and weighted-average assumptions used to determine net periodic benefit costs are as follows: For the years ended (dollars in thousands) 2017 2016 2015 Components of net periodic benefit cost: Service cost—benefits earned during year $ 2,578 $ 2,799 $ 3,355 Interest cost on projected benefit obligation 4,393 5,094 4,870 Expected return on plan assets (7,647 ) (7,719 ) (7,735 ) Amortization of prior service cost 26 26 26 Amortization of net loss 3,221 3,020 3,179 Net periodic pension cost $ 2,571 $ 3,220 $ 3,695 Other changes in plan assets and benefit obligations recognized in other comprehensive income: Net (gain) loss for period $ (300 ) $ 3,329 $ (5,106 ) Amortization of prior service cost (26 ) (26 ) (26 ) Amortization of net loss (3,221 ) (3,020 ) (3,179 ) Total recognized in other comprehensive income $ (3,547 ) $ 283 $ (8,311 ) Total recognized in net periodic pension cost and other comprehensive income $ (976 ) $ 3,503 $ (4,616 ) Weighted-average assumptions used to determine net periodic pension cost: Discount rate 4.46 % 4.74 % 4.33 % Rate of compensation increase 3.74 % 3.82 % 3.77 % Expected long-term return on assets 6.30 % 6.79 % 7.00 %
Summary of Weighted-Average Asset Allocations by Asset Category	The following table sets forth the Plan’s weighted-average asset allocations by asset category: Target Allocation for 2017 December 31, 2017 2016 Asset Category: Equity securities 55-75 % 64 % 62 % Debt securities 25-55 % 32 % 35 % Cash and cash equivalents 0-5 % 4 % 3 % Total 100 % 100 %
Fair Values of the WesBanco's Pension Plan Assets	The fair values of WesBanco’s pension plan assets at December 31, 2017 and 2016, by asset category are as follows: December 31, 2017 Fair Value Measurements Using: (in thousands) Assets at Fair Quoted Prices in Significant Significant (Level 3) Defined benefit pension plan assets: Registered investment companies $ 39,799 $ 39,799 $ — $ — Equity securities 64,128 64,128 — — Corporate debt securities 16,147 — 16,147 — Municipal obligations 3,004 — 3,004 — Residential mortgage-backed securities and collateralized mortgage obligations of government agencies 19,322 — 19,322 — Total defined benefit pension plan assets (1) $ 142,400 $ 103,927 $ 38,473 $ — (1) The defined benefit pension plan statement of net assets also includes cash, accrued interest and dividends, and due to/from brokers resulting in net assets available for benefits of $142.4 million. December 31, 2016 Fair Value Measurements Using: (in thousands) Assets at Fair Quoted Prices in Significant Significant (Level 3) Defined benefit pension plan assets: Registered investment companies $ 21,935 $ 21,935 $ — $ — Equity securities 60,144 60,144 — — Corporate debt securities 18,110 — 18,110 — Municipal obligations 2,998 — 2,998 — Residential mortgage-backed securities and collateralized mortgage obligations of government agencies 17,176 — 17,176 — Total defined benefit pension plan assets (1) $ 120,363 $ 82,079 $ 38,284 $ — (1) The defined benefit pension plan statement of net assets also includes cash, accrued interest and dividends, and due to/from brokers resulting in net assets available for benefits of $121.6 million.
Estimated Benefits to be Paid in Each of Next Five Years and in the Aggregate for the Five Years Thereafter	The following table presents estimated benefits to be paid in each of the next five years and in the aggregate for the five years thereafter ( in thousands Year Amount 2018 $ 4,014 2019 4,524 2020 4,839 2021 5,277 2022 5,599 2023 to 2027 33,631
Significant Assumptions Used in Calculating the Fair Value of the Grants	The following table sets forth the significant assumptions used in calculating the fair value of the grants: For the years ended December 31, 2017 2016 2015 Weighted-average life 5.2 years 5.1 years 4.9 years Risk-free interest rate 1.91 % 1.43 % 1.54 % Dividend yield 2.67 % 2.97 % 2.91 % Volatility factor 21.47 % 23.92 % 26.27 % Fair value of the grants $ 6.02 $ 5.09 $ 5.57
Summary of Activity for the Stock Option Component of the Incentive Plan	The following table shows the activity for the Stock Option component of the Incentive Plan: For the year ended Number Weighted Outstanding at beginning of the year 276,122 $ 29.71 Granted during the year 117,550 38.88 Exercised during the year (53,584 ) 27.96 Forfeited or expired during the year (3,400 ) 28.83 Outstanding at end of the year 336,688 $ 33.20 Exercisable at year end 277,913 $ 31.99
Summary of Average Remaining Life of the Stock Options	The following table shows the average remaining life of the stock options at December 31, 2017: Year Issued Exercisable Exercise Options Weighted Weighted Avg. 2011 2,750 $ 19.76 2,750 $ 19.76 0.38 2012 6,750 20.02 6,750 20.02 1.37 2013 24,000 25.00 24,000 25.00 2.37 2014 40,550 28.79 40,550 28.79 3.39 2015 59,488 31.58 59,488 31.58 4.42 2016 85,600 32.37 85,600 32.37 5.40 2017 58,775 38.88 117,550 38.88 6.35 Total 277,913 $ 19.76 to $38.88 336,688 $ 33.20 4.98
Schedule of Activity for the Restricted Stock Component of the Plan	The following table shows the activity for the Restricted Stock component of the Incentive Plan: For the year ended December 31, 2017 Restricted Weighted Non-vested at January 1, 2017 170,482 $ 31.40 Granted during the year 79,324 38.88 Vested during the year (42,029 ) 29.13 Forfeited or expired during the year (4,068 ) 31.34 Dividend reinvestment 4,681 40.65 Non-vested at end of the year 208,390 $ 34.91

Other Operating Expenses (Table

Other Operating Expenses (Tables)	12 Months Ended
	Dec. 31, 2017
Other Income and Expenses [Abstract]
Schedule of Other Operating Expenses	Other operating expenses consist of miscellaneous taxes, consulting fees, ATM expenses, postage, supplies, legal fees, communications, other real estate owned and foreclosure expenses, and other expenses. Other operating expenses are presented below: For the years ended December 31, (in thousands) 2017 2016 2015 Franchise and other miscellaneous taxes $ 8,423 $ 6,825 $ 5,924 Consulting, regulatory and advisory fees 6,857 6,270 4,959 ATM and electronic banking interchange expenses 4,510 4,297 4,463 Postage and courier expenses 3,879 3,306 3,720 Supplies 3,033 2,919 2,841 Legal fees 2,781 2,406 2,418 Communications 2,487 1,800 1,537 Other real estate owned and foreclosure expenses 1,097 1,210 546 Other 12,263 11,967 12,479 Total other operating expenses $ 45,330 $ 41,000 $ 38,887

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Reconciliation from Federal Statutory Income Tax Rate to Effective Tax Rate	Reconciliation from the federal statutory income tax rate to the effective tax rate is as follows: For the years ended December 31, 2017 2016 2015 Federal statutory tax rate 35.0 % 35.0 % 35.0 % Tax reform remeasurement 8.6 % 0.0 % 0.0 % Net tax-exempt (6.0 %) (7.0 %) (6.8 %) State income taxes, net of federal tax effect 1.3 % 1.4 % 1.6 % Bank-owned life insurance (1.1 %) (1.2 %) (1.6 %) General business credits (1.7 %) (2.1 %) (2.1 %) All other—net 0.2 % 0.3 % (0.1 %) Effective tax rate 36.3 % 26.4 % 26.0 %
Provision for Income Taxes Applicable to Income Before Taxes	The provision for income taxes applicable to income before taxes consists of the following: For the years ended December 31, (in thousands) 2017 2016 2015 Current: Federal $ 24,634 $ 18,053 $ 15,661 State 2,061 2,159 2,089 Deferred: Tax reform remeasurement 12,765 — — Federal 13,329 10,519 10,047 State 1,018 305 618 Total $ 53,807 $ 31,036 $ 28,415
Schedule of Income Tax Amounts were Recorded in Shareholder's Equity as Elements of Other Comprehensive Income	The following income tax amounts were recorded in shareholders’ equity as elements of other comprehensive income: For the years ended December 31, (in thousands) 2017 2016 2015 Securities and defined benefit pension plan unrecognized items $ 345 $ (3,480 ) $ (1,202 )
Schedule of Deferred Tax Assets and Liabilities	Deferred tax assets and liabilities consist of the following: December 31, (in thousands) 2017 2016 2015 Deferred tax assets: Allowance for loan losses $ 10,389 $ 16,198 $ 15,246 Compensation and benefits 2,536 5,444 6,114 Security gains and losses 821 2,854 2,964 Purchase accounting adjustments 1,565 — 1,275 Partnership adjustments — — 1,921 Non-accrual 1,389 2,392 2,254 Tax credit carryforwards 5,204 12,744 13,580 Net operating loss carryforwards 6,062 12,020 — Fair value adjustments on securities available-for-sale 3,962 5,394 1,979 Other 1,118 5,194 2,264 Gross deferred tax assets 33,046 62,240 47,597 Deferred tax liabilities: Depreciation and amortization (1,883 ) (3,448 ) (1,530 ) Accretion on securities (266 ) (421 ) (2 ) Deferred fees and costs (2,989 ) — — Purchase accounting adjustments — (149 ) — Partnership adjustments (674 ) (1,128 ) — Other (120 ) (2,519 ) (1,511 ) Gross deferred tax liabilities (5,932 ) (7,665 ) (3,043 ) Net deferred tax assets $ 27,114 $ 54,575 $ 44,554
Schedule of Unrecognized Tax Benefits (Excluding Interest and Federal Income Tax Benefit of Unrecognized State Tax Benefits)	A reconciliation of the beginning and ending amount of unrecognized tax benefits (excluding interest and the federal income tax benefit of unrecognized state tax benefits) is as follows: For the years ended (in thousands) 2017 2016 2015 Balance at beginning of year $ 436 $ 326 $ 701 Additions based on tax positions related to the current year 101 110 104 Reductions for tax positions of prior years — — (100 ) Reductions due to the statute of limitations (70 ) — (379 ) Settlements — — — Balance at end of year $ 467 $ 436 $ 326

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Assets and Liabilities Measured on Recurring and Nonrecurring Basis	The following tables set forth WesBanco’s financial assets and liabilities that were accounted for at fair value on a recurring and nonrecurring basis by level within the fair value hierarchy as of December 31, 2017 and 2016: December 31, 2017 Fair Value Measurements Using: (in thousands) December 31, Quoted Prices in Significant Significant Investments Recurring fair value measurements Trading securities $ 7,844 $ 5,778 $ — $ — $ 2,066 Securities—available-for-sale U.S. Government sponsored entities and agencies 71,843 — 71,843 — — Residential mortgage-backed securities and collateralized mortgage obligations of government agencies 934,922 — 934,922 — — Commercial mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 114,867 — 114,867 — — Obligations of state and political subdivisions 104,830 — 104,830 — — Corporate debt securities 35,403 — 35,403 — — Equity securities 5,613 5,613 — — — Total securities—available-for-sale $ 1,267,478 $ 5,613 $ 1,261,865 $ — $ — Loans held for sale $ 20,320 $ — $ 20,320 $ — $ — Other assets—interest rate derivatives agreements $ 7,351 $ — $ 7,351 $ — $ — Total assets recurring fair value measurements $ 1,302,993 $ 11,391 $ 1,289,536 $ — $ 2,066 Other liabilities—interest rate derivatives agreements $ 7,345 $ — $ 7,345 $ — $ — Total liabilities recurring fair value measurements $ 7,345 $ — $ 7,345 $ — $ — Nonrecurring fair value measurements Impaired loans $ 1,717 $ — $ — $ 1,717 $ — Other real estate owned and repossessed assets 5,297 — — 5,297 — Total nonrecurring fair value measurements $ 7,014 $ — $ — $ 7,014 $ — December 31, 2016 Fair Value Measurements Using: (in thousands) December 31, Quoted Prices in (level 1) Significant Significant Investments Recurring fair value measurements Trading securities $ 7,071 $ 5,633 $ — $ — $ 1,438 Securities—available-for-sale U.S. Government sponsored entities and agencies 54,043 — 54,043 — — Residential mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 938,289 — 938,289 — — Commercial mortgage-backed securities and collateralized mortgage obligations of government sponsored entities and agencies 96,810 — 96,810 — — Obligations of state and political subdivisions 111,663 — 111,663 — — Corporate debt securities 35,301 — 35,301 — — Equity securities 5,070 2,938 2,132 — — Total securities—available-for-sale $ 1,241,176 $ 2,938 $ 1,238,238 $ — $ — Other assets—interest rate derivatives agreements $ 5,596 $ — $ 5,596 $ — $ — Total assets recurring fair value measurements $ 1,253,843 $ 8,571 $ 1,243,834 $ — $ 1,438 Other liabilities—interest rate derivatives agreements $ 5,199 — $ 5,199 — — Total liabilities recurring fair value measurements $ 5,199 $ — $ 5,199 $ — $ — Nonrecurring fair value measurements Impaired loans $ 3,405 $ — $ — $ 3,405 $ — Other real estate owned and repossessed assets 8,346 — — 8,346 — Loans held for sale 17,315 — 17,315 — — Total nonrecurring fair value measurements $ 29,066 $ — $ 17,315 $ 11,751 $ —
Schedule of Assets Measured at Fair Value on Nonrecurring Basis	The following table presents additional quantitative information about assets measured at fair value on a nonrecurring basis and for which WesBanco has utilized level 3 inputs to determine fair value: Quantitative Information about Level 3 Fair Value Measurements (in thousands) Fair Value Valuation Techniques Unobservable Input Range / Weighted Average December 31, 2017: Impaired loans $ 1,717 Appraisal of collateral (1) Appraisal adjustments (2) (4.8%) /(4.8%) Liquidation expenses (2) (7.6%) /(7.6%) Other real estate owned and repossessed assets 5,297 Appraisal of collateral (1)(3) December 31, 2016: Impaired loans $ 3,405 Appraisal of collateral (1) Appraisal adjustments (2) 0% to (70.0%) /(36.6%) Liquidation expenses (2) (1.5%) to (8.0%) /(4.6%) Other real estate owned and repossessed assets 8,346 Appraisal of collateral (1)(3) (1) Fair value is generally determined through independent appraisals of the underlying collateral, which generally include various level 3 inputs which are not identifiable. (2) Appraisals may be adjusted by management for qualitative factors such as economic conditions and estimated liquidation expenses. The range and weighted average of appraisal adjustments and liquidation expenses are presented as a percent of the appraisal. (3) Includes estimated liquidation expenses and numerous dissimilar qualitative adjustments by management which are not identifiable.
Estimates Fair Values of Financial Instruments	The estimated fair values of WesBanco’s financial instruments are summarized below: Carrying Fair Value Fair Value Measurements at December 31, 2017 (in thousands) Quoted Prices in (level 1) Significant (level 2) Significant (level 3) Investments Financial Assets Cash and due from banks $ 117,572 $ 117,572 $ 117,572 $ — $ — $ — Trading securities 7,844 7,844 5,778 — — 2,066 Securities available-for-sale 1,267,478 1,267,478 5,613 1,261,865 — — Securities held-to-maturity 1,009,500 1,023,784 — 1,023,191 593 — Net loans 6,296,157 6,212,823 — — 6,212,823 — Loans held for sale 20,320 20,320 — 20,320 — — Other assets—interest rate derivatives 7,351 7,351 — 7,351 — — Accrued interest receivable 29,728 29,728 29,728 — — — Financial Liabilities Deposits 7,043,588 7,053,536 5,766,531 1,287,005 — — Federal Home Loan Bank borrowings 948,203 944,706 — 944,706 — — Other borrowings 184,805 184,814 182,785 2,029 — — Subordinated debt and junior subordinated debt 164,327 146,484 — 146,484 — — Other liabilities—interest rate derivatives 7,345 7,345 — 7,345 — — Accrued interest payable 3,178 3,178 3,178 — — — Carrying Fair Value Fair Value Measurements at December 31, 2016 (in thousands) Quoted Significant Significant Investments Financial Assets Cash and due from banks $ 128,170 $ 128,170 $ 128,170 $ — $ — $ — Trading securities 7,071 7,071 5,633 — — 1,438 Securities available-for-sale 1,241,176 1,241,176 2,938 1,238,238 — — Securities held-to-maturity 1,067,967 1,076,790 — 1,076,189 601 — Net loans 6,205,762 6,073,558 — — 6,073,558 — Loans held for sale 17,315 17,315 — 17,315 — — Other assets—interest rate derivatives 5,596 5,596 — 5,596 — — Accrued interest receivable 28,299 28,299 28,299 — — — Financial Liabilities Deposits 7,040,879 7,052,501 5,545,057 1,507,444 — — Federal Home Loan Bank borrowings 968,946 974,430 — 974,430 — — Other borrowings 199,376 199,385 197,164 2,221 — — Subordinated debt and junior subordinated debt 163,598 134,859 — 134,859 — — Other liabilities—interest rate derivatives 5,199 5,199 — 5,199 — — Accrued interest payable 2,204 2,204 2,204 — — —

Comprehensive Income_(Loss) (Ta

Comprehensive Income/(Loss) (Tables)	12 Months Ended
	Dec. 31, 2017
Equity [Abstract]
Components of Accumulated Other Comprehensive Income/(Loss)	The activity in accumulated other comprehensive income/(loss) for the years ended December 31, 2017, 2016 and 2015 is as follows: Accumulated Other Comprehensive Income/(Loss) (1) (in thousands) Defined Unrealized Gains Available-for-Sale Unrealized Gains Available-for-Sale to Held-to-Maturity Total Balance at December 31, 2016 $ (17,758 ) $ (9,890 ) $ 522 $ (27,126 ) Other comprehensive income/(loss) before reclassifications 239 (985 ) — (746 ) Amounts reclassified from accumulated other comprehensive income/(loss) 2,194 (27 ) (209 ) 1,958 Period change 2,433 (1,012 ) (209 ) 1,212 Adoption of accounting standard ASU 2018-02 (3,301 ) (2,348 ) 68 (5,581 ) Balance at December 31, 2017 $ (18,626 ) $ (13,250 ) $ 381 $ (31,495 ) Balance at December 31, 2015 $ (17,539 ) $ (4,162 ) $ 747 $ (20,954 ) Other comprehensive income/(loss) before reclassifications (2,112 ) (4,300 ) — (6,412 ) Amounts reclassified from accumulated other comprehensive income/(loss) 1,893 (1,428 ) (225 ) 240 Period change (219 ) (5,728 ) (225 ) (6,172 ) Balance at December 31, 2016 $ (17,758 ) $ (9,890 ) $ 522 $ (27,126 ) Balance at December 31, 2014 $ (22,776 ) $ 2,892 $ 1,059 $ (18,825 ) Other comprehensive income/(loss) before reclassifications 3,233 (6,677 ) — (3,444 ) Amounts reclassified from accumulated other comprehensive income/(loss) 2,004 (377 ) (312 ) 1,315 Period change 5,237 (7,054 ) (312 ) (2,129 ) Balance at December 31, 2015 $ (17,539 ) $ (4,162 ) $ 747 $ (20,954 ) (1) All amounts are net of tax. Related income tax expense or benefit is calculated using a combined Federal and State income tax rate approximating 37%.
Schedule of Amounts Reclassified from Accumulated Other Comprehensive Income/(Loss)	Details about Accumulated Other Comprehensive Amounts Reclassified from Affected Line Item in the Statement of Net (in thousands) 2017 2016 2015 Securities available-for-sale Net securities gains reclassified into earnings $ (42 ) $ (2,251 ) $ (596 ) Net securities gains (Non-interest Related income tax expense 15 823 219 Provision for income taxes Net effect on accumulated other comprehensive income/(loss) for the period (27 ) (1,428 ) (377 ) Securities held-to-maturity Amortization of unrealized gain transferred from available-for-sale (326 ) (357 ) (494 ) Interest and dividends on securities (Interest and dividend income) Related income tax expense 117 132 182 Provision for income taxes Net effect on accumulated other comprehensive income/(loss) for the period (209 ) (225 ) (312 ) Defined benefit pension plan (2): Amortization of net loss and prior service costs 3,247 3,046 3,205 Employee benefits (Non-interest Related income tax benefit (1,053 ) (1,153 ) (1,201 ) Provision for income taxes Net effect on accumulated other comprehensive income/(loss) for the period 2,194 1,893 2,004 Total reclassifications for the period $ 1,958 $ 240 $ 1,315 (1) For additional detail related to unrealized gains on securities and related amounts reclassified from accumulated other comprehensive income/(loss) see Note 4, “Securities.” (2) Included in the computation of net periodic pension cost. See Note 13, “Employee Benefit Plans” for additional detail.

Commitments and Contingent Li49

Commitments and Contingent Liabilities (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments to Extend Credit, Guarantees and Various Letters of Credit Outstanding	The following table presents total commitments to extend credit, guarantees and various letters of credit outstanding: December 31, (in thousands) 2017 2016 Lines of credit $ 1,452,697 $ 1,418,329 Loans approved but not closed 245,644 185,254 Overdraft limits 126,671 126,517 Letters of credit 31,951 32,907 Contingent obligations to purchase loans funded by other entities 6,700 13,036

Wesbanco Bank Community Devel50

Wesbanco Bank Community Development Corporation (Tables)	12 Months Ended
	Dec. 31, 2017
Text Block [Abstract]
Summary of New Market Tax Credit Carry Forward	( in thousands ) Aggregate QEI New Markets Tax Credit Year 2018 2019 2012 $ 6,000 $ 360 $ — 2013 5,000 300 300 Total $ 11,000 $ 660 $ 300 (1) The seven-year credit allowance period has expired for $49.0 million in QEI investments in WBCDC.

Condensed Parent Company Fina51

Condensed Parent Company Financial Statements (Tables)	12 Months Ended
	Dec. 31, 2017
WBCDC [Member]
Schedule of Condensed Balance Sheet	BALANCE SHEET (in thousands) December 31, Assets Cash and due from banks $ 36,533 Loans, net of allowance for loan losses of $254 35,218 Investments 820 Other assets 195 Total Assets $ 72,766 Liabilities $ 354 Shareholder Equity 72,412 Total Liabilities and Shareholder Equity $ 72,766
Schedule of Condensed Income Statement	STATEMENT OF INCOME (in thousands) For the year ended Interest income Loans $ 1,282 Total interest income 1,282 Provision for loan losses 5 Net interest income after provision for loan losses 1,277 Loss on investments (148 ) Non-interest 235 Income before provision for income taxes 894 Provision for income taxes 354 Net income $ 540
Schedule of Condensed Cash Flow Statement	STATEMENT OF CASH FLOWS (in thousands) For the year ended Operating Activities Net income $ 540 Provision for loan losses 5 Loss on investments 148 Net change in other assets 91 Net change in other liabilities 80 Net cash provided by operating activities 864 Investing Activities Decrease in loans 4,366 Net cash provided by investing activities 4,366 Financing Activities Qualified equity investment by parent company — Net cash provided by financing activities — Net increase in cash and cash equivalents 5,230 Cash and cash equivalents at beginning of year 31,303 Cash and cash equivalents at end of year $ 36,533
Parent Company [Member]
Schedule of Condensed Balance Sheet	BALANCE SHEETS December 31, (in thousands) 2017 2016 ASSETS Cash and short-term investments $ 75,911 $ 47,035 Investment in subsidiaries—Bank 1,431,021 1,404,565 Investment in subsidiaries—Nonbank 7,755 8,228 Securities available-for-sale, 2,687 2,133 Other assets 28,614 28,602 Total Assets $ 1,545,988 $ 1,490,563 LIABILITIES Junior subordinated debt owed to unconsolidated subsidiary trusts $ 138,564 $ 137,559 Dividends payable and other liabilities 12,103 11,596 Total Liabilities 150,667 149,155 SHAREHOLDERS’ EQUITY 1,395,321 1,341,408 Total Liabilities and Shareholders’ Equity $ 1,545,988 $ 1,490,563
Schedule of Condensed Income Statement	STATEMENTS OF INCOME For the years ended December 31, (in thousands) 2017 2016 2015 Dividends from subsidiaries—Bank $ 72,000 $ 85,000 $ 60,000 Dividends from subsidiaries—Nonbank 2,520 800 500 Income from securities 73 75 75 Other income 203 147 104 Total income 74,796 86,022 60,679 Interest expense 6,032 4,136 3,315 Other expense 4,004 5,628 5,547 Total expense 10,036 9,764 8,862 Income before income tax benefit and undistributed net income of subsidiaries 64,760 76,258 51,817 Income tax benefit (4,726 ) (3,149 ) (2,971 ) Income before undistributed net income of subsidiaries 69,486 79,407 54,788 Equity in undistributed net income of subsidiaries 24,996 7,228 25,974 NET INCOME $ 94,482 $ 86,635 $ 80,762
Schedule of Condensed Cash Flow Statement	STATEMENTS OF CASH FLOWS For the years ended December 31, (in thousands) 2017 2016 2015 OPERATING ACTIVITIES Net income $ 94,482 $ 86,635 $ 80,762 Adjustments to reconcile net income to net cash provided by operating activities: Equity in undistributed net income (24,996 ) (7,228 ) (25,974 ) Decrease in other assets 566 14,679 199 Other—net 2,848 2,094 1,657 Net cash provided by operating activities 72,900 96,180 56,644 INVESTING ACTIVITIES Proceed from sales —securities available-for-sale — — 210 Purchase of securities —securities available-for-sale (200 ) — — Acquisitions and additional capitalization of subsidiaries, net of cash (paid) acquired — (43,199 ) 1,465 Net cash (used in) provided by investing activities (200 ) (43,199 ) 1,675 FINANCING ACTIVITIES Repayment of junior subordinated debt — — (36,083 ) Repayment of other borrowings — — (13,000 ) Issuance of common stock 1,040 1,713 — Repurchase of common stock warrant — — (2,247 ) Treasury shares (purchased) sold—net — (3,026 ) (2,542 ) Dividends paid to common and preferred shareholders (44,864 ) (37,805 ) (33,007 ) Net cash used in financing activities (43,824 ) (39,118 ) (86,879 ) Net increase (decrease) in cash and cash equivalents 28,876 13,863 (28,560 ) Cash and short-term investments at beginning of year 47,035 33,172 61,732 Cash and short-term investments at end of year $ 75,911 $ 47,035 $ 33,172

Regulatory Matters (Tables)

Regulatory Matters (Tables)	12 Months Ended
	Dec. 31, 2017
Banking and Thrift [Abstract]
Summary of Risk-Based Capital Amounts and Ratios	The following table summarizes risk-based capital amounts and ratios for WesBanco and the Bank: December 31, 2017 December 31, 2016 (dollars in thousands) Minimum Well Amount Ratio Minimum Amount Ratio Minimum WesBanco, Inc. Tier 1 leverage 4.00 % 5.00 % $ 970,425 10.39 % $ 373,566 $ 901,873 9.81 % $ 367,843 Common equity Tier 1 4.50 % 6.50 % 834,554 12.14 % 309,298 773,306 11.28 % 308,462 Tier 1 capital to risk-weighted assets 6.00 % 8.00 % 970,425 14.12 % 412,397 901,873 13.16 % 411,283 Total capital to risk-weighted assets 8.00 % 10.00 % 1,042,124 15.16 % 549,863 971,762 14.18 % 548,378 WesBanco Bank, Inc. Tier 1 leverage 4.00 % 5.00 % $ 869,227 9.32 % $ 372,900 $ 827,173 9.02 % $ 366,903 Common equity Tier 1 4.50 % 6.50 % 869,227 12.66 % 308,900 827,173 12.10 % 307,728 Tier 1 capital to risk-weighted assets 6.00 % 8.00 % 869,227 12.66 % 411,866 827,173 12.10 % 410,305 Total capital to risk-weighted assets 8.00 % 10.00 % 940,303 13.70 % 549,155 896,598 13.11 % 547,073 (1) Minimum requirements to remain adequately capitalized. (2) Well capitalized under prompt corrective action regulations.

Business Segments (Tables)

Business Segments (Tables)	12 Months Ended
	Dec. 31, 2017
Segment Reporting [Abstract]
Financial Information by Business Segment	Condensed financial information by business segment is presented below: (in thousands) Community Trust and Consolidated For the year ended December 31, 2017: Interest and dividend income $ 332,424 $ — 332,424 Interest expense 42,129 — 42,129 Net interest income 290,295 — 290,295 Provision for credit losses 9,986 — 9,986 Net interest income after provision for credit losses 280,309 — 280,309 Non-interest 66,100 22,740 88,840 Non-interest 207,441 13,419 220,860 Income before provision for income taxes 138,968 9,321 148,289 Provision for income taxes 50,079 3,728 53,807 Net income $ 88,889 $ 5,593 $ 94,482 For the year ended December 31, 2016: Interest and dividend income $ 286,097 $ — $ 286,097 Interest expense 32,767 — 32,767 Net interest income 253,330 — 253,330 Provision for credit losses 8,478 — 8,478 Net interest income after provision for credit losses 244,852 — 244,852 Non-interest 59,869 21,630 81,499 Non-interest 196,784 11,896 208,680 Income before provision for income taxes 107,937 9,734 117,671 Provision for income taxes 27,142 3,894 31,036 Net income $ 80,795 $ 5,840 $ 86,635 For the year ended December 31, 2015: Interest and dividend income $ 261,712 $ — $ 261,712 Interest expense 24,725 — 24,725 Net interest income 236,987 — 236,987 Provision for credit losses 8,353 — 8,353 Net interest income after provision for credit losses 228,634 — 228,634 Non-interest 52,566 21,900 74,466 Non-interest 181,821 12,102 193,923 Income before provision for income taxes 99,379 9,798 109,177 Provision for income taxes 24,496 3,919 28,415 Net income $ 74,883 $ 5,879 $ 80,762

Condensed Quarterly Statement54

Condensed Quarterly Statements of Income (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Consolidated Selected Quarterly Statements of Income	The following tables set forth unaudited consolidated selected quarterly statements of income for the years ended December 31, 2017 and 2016. 2017 Quarter ended (dollars in thousands, except per share amounts) March 31, June 30, September 30, December 31, Annual Total Interest and dividend income $ 79,924 $ 82,160 $ 85,489 $ 84,851 $ 332,424 Interest expense 9,205 10,021 11,235 11,669 42,129 Net interest income 70,719 72,139 74,254 73,182 290,295 Provision for credit losses 2,711 2,383 2,516 2,376 9,986 Net interest income after provision for credit losses 68,008 69,756 71,738 70,806 280,309 Non-interest 22,872 21,628 20,893 22,878 88,273 Net securities gains 12 494 6 56 567 Non-interest 54,384 55,884 55,754 54,837 220,860 Income before provision for income taxes 36,508 35,994 36,883 38,903 148,289 Provision for income taxes 10,622 9,653 10,527 23,006 53,807 Net income $ 25,886 $ 26,341 $ 26,356 $ 15,897 $ 94,482 Earnings per common share—basic $ 0.59 $ 0.60 $ 0.60 $ 0.36 $ 2.15 Earnings per common share—diluted $ 0.59 $ 0.60 $ 0.60 $ 0.36 $ 2.14 2016 Quarter ended (dollars in thousands, except per share amounts) March 31, June 30, September 30, December 31, Annual Interest and dividend income $ 67,601 $ 67,585 $ 70,092 $ 80,819 $ 286,097 Interest expense 7,759 7,811 8,066 9,131 32,767 Net interest income 59,842 59,774 62,026 71,688 253,330 Provision for credit losses 2,324 1,811 2,214 2,128 8,478 Net interest income after provision for credit losses 57,518 57,963 59,812 69,560 244,852 Non-interest 18,282 19,006 20,419 21,357 79,142 Net securities gains 1,111 585 598 63 2,357 Non-interest 45,343 47,360 57,601 58,298 208,680 Income before provision for income taxes 31,568 30,194 23,228 32,682 117,671 Provision for income taxes 8,694 8,085 5,793 8,464 31,036 Net income $ 22,874 $ 22,109 $ 17,435 $ 24,218 $ 86,635 Earnings per common share—basic $ 0.60 $ 0.58 $ 0.44 $ 0.55 $ 2.16 Earnings per common share—diluted $ 0.60 $ 0.58 $ 0.44 $ 0.55 $ 2.16

Summary of Significant Accoun55

Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended	12 Months Ended
	Dec. 31, 2017USD ($)Branches	Dec. 31, 2017USD ($)BranchesProperty	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of branches | Branches	172	172
Number of ATM | Property		160
Wholly-owned trust subsidiaries | Property		12
Held for sale securities, percentage of purchase price as condition for sale		15.00%
Allowance for credit losses carryover		$ 0
Non-accrual status period		90 days
Loans returned to accrual status, performance period		6 months
Minimum loan balance individually tested for impairment	$ 1,000,000	$ 1,000,000
Indefinite - lived intangible assets	0	$ 0
Period of interest rate lock commitments		60 days
Service cost component of defined benefit plan		$ 2,578,000	$ 2,799,000	$ 3,355,000
Partnerships losses and impairment	$ 300,000	$ 1,500,000
Land Improvements [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment, Useful life		15 years
Consumer Loan [Member]
Summary Of Significant Accounting Policies [Line Items]
Period of closed end loans loans charged down to net realizable value		120 days
Home Equity [Member]
Summary Of Significant Accounting Policies [Line Items]
Period of closed end loans loans charged down to net realizable value		180 days
Residential Real Estate Loans [Member]
Summary Of Significant Accounting Policies [Line Items]
Period of closed end loans loans charged down to net realizable value		180 days
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of voting interest	50.00%	50.00%
Weighted-average estimated useful lives		10 years
Non-compete agreements, amortization period		1 year
Minimum [Member] | Furniture and Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment, Useful life		3 years
Minimum [Member] | Building and Building Improvements [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment, Useful life		15 years
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Weighted-average estimated useful lives		16 years
Non-compete agreements, amortization period		4 years
Maximum [Member] | Furniture and Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment, Useful life		10 years
Maximum [Member] | Building and Building Improvements [Member]
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment, Useful life		39 years

Mergers and Acquisitions - Addi

Mergers and Acquisitions - Additional Information (Detail) $ / shares in Units, $ in Thousands	Nov. 13, 2017USD ($)Branch	Sep. 09, 2016USD ($)$ / sharesshares	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)shares	Dec. 31, 2015shares
Your Community Bankshares, Inc [Member]
Business Acquisition [Line Items]
Total assets acquired, excluding goodwill		$ 1,500,000
Deposits		1,193,010
Loans		1,012,410
Value of acquisition		220,498
Securities		$ 173,223
Common shares issued | shares		5,423,348
Cash consideration for outstanding YCB shares		$ 43,349
Goodwill acquired		93,033	$ 93,033
Purchase price allocation in core deposit intangible		$ 11,957
Closing stock price | $ / shares		$ 32.62
Merger related expense			$ 500	$ 13,300
First Sentry Bancshares, Inc. [Member] | West Virginia [Member]
Business Acquisition [Line Items]
Total assets acquired, excluding goodwill	$ 658,200
Deposits	527,600
Loans	402,400
Value of acquisition	$ 101,400
Total assets acquired, excluding goodwill | Branch	5
Common Stock [Member]
Business Acquisition [Line Items]
Common shares issued | shares				5,423,348	9,178,531
Common Stock [Member] | Your Community Bankshares, Inc [Member]
Business Acquisition [Line Items]
Common shares issued | shares		5,423,348
Cash consideration for outstanding YCB shares		$ 43,300

Mergers and Acquisitions - Summ

Mergers and Acquisitions - Summary of Purchase Price of Acquisition and Resulting Goodwill (Detail) - Your Community Bankshares, Inc [Member] - USD ($) $ in Thousands	Sep. 09, 2016	Dec. 31, 2017
Purchase Price:
Fair value of WesBanco shares issued	$ 177,149
Cash consideration for outstanding YCB shares	43,349
Total purchase price	220,498
Fair value of:
Tangible assets acquired	1,398,183
Core deposit and other intangible assets acquired	11,957
Liabilities assumed	(1,330,887)
Net cash received in the acquisition	48,212
Fair value of net assets acquired	127,465
Goodwill recognized	$ 93,033	$ 93,033

Mergers and Acquisitions - Allo

Mergers and Acquisitions - Allocation of Purchase Price of Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Sep. 09, 2016
Liabilities
Goodwill recognized	$ 573,900	$ 573,800
Purchase Price Allocation Adjustment [Member]
Business Acquisition [Line Items]
Loans	(1,156)
Accrued income and other assets	743
Liabilities
Accrued expenses and other liabilities	269
Fair value of net assets acquired	(144)
Increase in goodwill recognized	144
Goodwill recognized	$ 93,033	$ 92,889
Your Community Bankshares, Inc [Member]
Business Acquisition [Line Items]
Cash and due from banks			$ 48,212
Securities			173,223
Loans			1,012,410
Goodwill and other intangible assets			104,990
Accrued income and other assets			212,550
Total assets acquired			1,551,385
Liabilities
Deposits			1,193,010
Borrowings			123,001
Accrued expenses and other liabilities			14,876
Total liabilities assumed			1,330,887
Fair value of net assets acquired			127,465
Net assets acquired			$ 220,498

Mergers and Acquisitions - Al59

Mergers and Acquisitions - Allocation of Purchase Price of Assets Acquired and Liabilities Assumed (Parenthetical) (Detail) $ in Millions	Sep. 09, 2016USD ($)
Your Community Bankshares, Inc [Member]
Business Acquisition [Line Items]
Receivables from sale of available-for-sale securities	$ 105.8

Earnings Per Common Share - Sum

Earnings Per Common Share - Summary of Earnings Per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Numerator for both basic and diluted earnings per common share:
Net income	$ 15,897	$ 26,356	$ 26,341	$ 25,886	$ 24,218	$ 17,435	$ 22,109	$ 22,874	$ 94,482	$ 86,635	$ 80,762
Denominator:
Total average basic common shares outstanding									44,003,208	40,100,320	37,488,331
Effect of dilutive stock options and other stock compensation									72,085	26,756	58,796
Total diluted average common shares outstanding									44,075,293	40,127,076	37,547,127
Earnings per common share-basic	$ 0.36	$ 0.60	$ 0.60	$ 0.59	$ 0.55	$ 0.44	$ 0.58	$ 0.60	$ 2.15	$ 2.16	$ 2.15
Earnings per common share-diluted	$ 0.36	$ 0.60	$ 0.60	$ 0.59	$ 0.55	$ 0.44	$ 0.58	$ 0.60	$ 2.14	$ 2.16	$ 2.15

Earnings Per Common Share - Add

Earnings Per Common Share - Additional Information (Detail) - shares	Sep. 09, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of net income per diluted shares			95,700
Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Securities excluded from computation of net income per diluted shares		24,675	24,000	12,000
Your Community Bankshares, Inc [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares issued for acquisition, shares	5,423,348
Your Community Bankshares, Inc [Member] | Treasury Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Shares issued for acquisition, shares	109,257

Securities - Schedule of Amorti

Securities - Schedule of Amortized Cost and Fair Value of Available-for-sale and Held-to-maturity Securities (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale, Amortized Cost	$ 1,284,808	$ 1,256,762
Available-for-sale, Gross Unrealized Gains	4,787	5,177
Available-for-sale, Gross Unrealized Losses	(22,117)	(20,763)
Available-for-sale, Estimated Fair Value	1,267,478	1,241,176
Held-to-maturity, Amortized Cost	1,009,500	1,067,967
Held-to-maturity, Gross Unrealized Gains	18,827	17,349
Held-to-maturity, Gross Unrealized Losses	(4,543)	(8,526)
Held-to-maturity securities, Fair value	1,023,784	1,076,790
Total, Amortized Cost	2,294,308	2,324,729
Total, Gross Unrealized Gains	23,614	22,526
Total, Gross Unrealized Losses	(26,660)	(29,289)
Total, Estimated Fair Value	2,291,262	2,317,966
U.S. Government Sponsored Entities and Agencies [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale, Amortized Cost	72,425	54,803
Available-for-sale, Gross Unrealized Gains	24	3
Available-for-sale, Gross Unrealized Losses	(606)	(763)
Available-for-sale, Estimated Fair Value	71,843	54,043
Held-to-maturity, Amortized Cost	11,465	13,394
Held-to-maturity, Gross Unrealized Losses	(325)	(414)
Held-to-maturity securities, Fair value	11,140	12,980
Residential Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Sponsored Entities and Agencies [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale, Amortized Cost	954,115	953,475
Available-for-sale, Gross Unrealized Gains	214	884
Available-for-sale, Gross Unrealized Losses	(19,407)	(16,070)
Available-for-sale, Estimated Fair Value	934,922	938,289
Held-to-maturity, Amortized Cost	170,025	215,141
Held-to-maturity, Gross Unrealized Gains	544	1,279
Held-to-maturity, Gross Unrealized Losses	(2,609)	(2,563)
Held-to-maturity securities, Fair value	167,960	213,857
Commercial Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Sponsored Entities and Agencies [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale, Amortized Cost	116,448	98,922
Available-for-sale, Gross Unrealized Gains	4	27
Available-for-sale, Gross Unrealized Losses	(1,585)	(2,139)
Available-for-sale, Estimated Fair Value	114,867	96,810
Obligations of State and Political Subdivisions [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale, Amortized Cost	102,363	110,208
Available-for-sale, Gross Unrealized Gains	2,927	3,114
Available-for-sale, Gross Unrealized Losses	(460)	(1,659)
Available-for-sale, Estimated Fair Value	104,830	111,663
Held-to-maturity, Amortized Cost	794,655	805,019
Held-to-maturity, Gross Unrealized Gains	17,364	15,652
Held-to-maturity, Gross Unrealized Losses	(1,609)	(5,529)
Held-to-maturity securities, Fair value	810,410	815,142
Corporate Debt Securities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale, Amortized Cost	35,234	35,292
Available-for-sale, Gross Unrealized Gains	228	117
Available-for-sale, Gross Unrealized Losses	(59)	(108)
Available-for-sale, Estimated Fair Value	35,403	35,301
Held-to-maturity, Amortized Cost	33,355	34,413
Held-to-maturity, Gross Unrealized Gains	919	418
Held-to-maturity, Gross Unrealized Losses		(20)
Held-to-maturity securities, Fair value	34,274	34,811
Debt Securities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale, Amortized Cost	1,280,585	1,252,700
Available-for-sale, Gross Unrealized Gains	3,397	4,145
Available-for-sale, Gross Unrealized Losses	(22,117)	(20,739)
Available-for-sale, Estimated Fair Value	1,261,865	1,236,106
Equity Securities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Available-for-sale, Amortized Cost	4,223	4,062
Available-for-sale, Gross Unrealized Gains	1,390	1,032
Available-for-sale, Gross Unrealized Losses		(24)
Available-for-sale, Estimated Fair Value	$ 5,613	$ 5,070

Securities - Additional Informa

Securities - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2017USD ($)Holdings	Dec. 31, 2016USD ($)Holdings	Dec. 31, 2015USD ($)
Investments, Debt and Equity Securities [Abstract]
Trading securities, at fair value	$ 7,844,000	$ 7,071,000
Maximum percentage of equity of one issuer	10.00%
Number of holdings greater than specified percentage of equity | Holdings	0	0
Securities with aggregate fair values	$ 1,400,000,000	$ 1,200,000,000
Proceeds from sale of available-for-sale securities	7,760,000	277,225,000	$ 635,609,000
Net unrealized losses on available-for-sale securities included in AOCI	13,300,000	9,900,000	$ 4,200,000
Impairment loss relating to securities	0
Federal home loan bank stock, Total	$ 45,900,000	$ 46,400,000

Securities - Schedule of Fair V

Securities - Schedule of Fair Value of Available-for-Sale and Held-to-Maturity Securities by Contractual Maturity (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Total available-for-sale securities, One Year or less	$ 17,892
Total available-for-sale securities, One to Five Years	47,248
Total available-for-sale securities, Five to Ten Years	60,839
Total available-for-sale securities, After Ten Years	49,907
Total available-for-sale securities, Mortgage-backed and Equity	1,091,592
Available-for-sale, Estimated Fair Value	1,267,478	$ 1,241,176
Total held-to-maturity securities, One Year or less	4,855
Total held-to-maturity securities, One to Five Years	114,223
Total held-to-maturity securities, Five to Ten Years	432,891
Total held-to-maturity securities, After Ten Years	292,715
Total held-to-maturity securities, Mortgage-backed and Equity	179,100
Held-to-maturity securities, Fair value	1,023,784	1,076,790
Total, One Year or less	22,747
Total, One to Five Years	161,471
Total, Five to Ten Years	493,730
Total, After Ten Years, Fair value	342,622
Total, Mortgage- backed and Equity	1,270,692
Total, Fair value	2,291,262	2,317,966
U.S. Government Sponsored Entities and Agencies [Member]
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Total available-for-sale securities, One Year or less	9,938
Total available-for-sale securities, One to Five Years	1,990
Total available-for-sale securities, Five to Ten Years	16,837
Total available-for-sale securities, After Ten Years	6,888
Total available-for-sale securities, Mortgage-backed and Equity	36,190
Available-for-sale, Estimated Fair Value	71,843	54,043
Total held-to-maturity securities, Mortgage-backed and Equity	11,140
Held-to-maturity securities, Fair value	11,140	12,980
Residential Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Sponsored Entities and Agencies [Member]
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Total available-for-sale securities, Mortgage-backed and Equity	934,922
Available-for-sale, Estimated Fair Value	934,922	938,289
Total held-to-maturity securities, Mortgage-backed and Equity	167,960
Held-to-maturity securities, Fair value	167,960	213,857
Commercial Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Sponsored Entities and Agencies [Member]
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Total available-for-sale securities, Mortgage-backed and Equity	114,867
Available-for-sale, Estimated Fair Value	114,867	96,810
Obligations of State and Political Subdivisions [Member]
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Total available-for-sale securities, One Year or less	3,964
Total available-for-sale securities, One to Five Years	18,827
Total available-for-sale securities, Five to Ten Years	39,020
Total available-for-sale securities, After Ten Years	43,019
Available-for-sale, Estimated Fair Value	104,830	111,663
Total held-to-maturity securities, One Year or less	4,855
Total held-to-maturity securities, One to Five Years	106,502
Total held-to-maturity securities, Five to Ten Years	406,338
Total held-to-maturity securities, After Ten Years	292,715
Held-to-maturity securities, Fair value	810,410	815,142
Corporate Debt Securities [Member]
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Total available-for-sale securities, One Year or less	3,990
Total available-for-sale securities, One to Five Years	26,431
Total available-for-sale securities, Five to Ten Years	4,982
Available-for-sale, Estimated Fair Value	35,403	35,301
Total held-to-maturity securities, One to Five Years	7,721
Total held-to-maturity securities, Five to Ten Years	26,553
Held-to-maturity securities, Fair value	34,274	34,811
Equity Securities [Member]
Schedule Of Available For Sale Securities And Held To Maturity [Line Items]
Total available-for-sale securities, Mortgage-backed and Equity	5,613
Available-for-sale, Estimated Fair Value	$ 5,613	$ 5,070

Securities - Schedule of Fair65

Securities - Schedule of Fair Value of Available-for-Sale and Held-to-Maturity Securities by Contractual Maturity (Parenthetical) (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Amortized Cost and Fair Value Debt Securities [Abstract]
Held-to-maturity, Amortized Cost	$ 1,009,500	$ 1,067,967

Securities - Schedule of Gross

Securities - Schedule of Gross Realized Gains and Losses on the Sales and Calls of Securities (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Securities Gross Realized Gain Loss [Abstract]
Gross realized gains	$ 675	$ 2,638	$ 1,029
Gross realized losses	(108)	(281)	(81)
Net realized gains	$ 567	$ 2,357	$ 948

Securities - Schedule of Unreal

Securities - Schedule of Unrealized Losses on Investment Securities (Detail) $ in Thousands	Dec. 31, 2017USD ($)Security	Dec. 31, 2016USD ($)Security
U.S. Government Sponsored Entities and Agencies [Member]
Net Unrealized Gains And Losses On Investments [Line Items]
Less than 12 months, Fair Value	$ 24,776	$ 58,108
Less than 12 months, Unrealized Losses	$ (160)	$ (1,177)
Less than 12 months, Number of Securities | Security	4	11
12 months or more, Fair Value	$ 42,248
12 months or more, Unrealized Losses	$ (771)
12 months or more, Number of Securities | Security	8
Fair Value, Total	$ 67,024	$ 58,108
Unrealized Losses, Total	$ (931)	$ (1,177)
Number of Securities Total | Security	12	11
Residential Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Sponsored Entities and Agencies [Member]
Net Unrealized Gains And Losses On Investments [Line Items]
Less than 12 months, Fair Value	$ 423,794	$ 969,174
Less than 12 months, Unrealized Losses	$ (5,039)	$ (16,436)
Less than 12 months, Number of Securities | Security	87	232
12 months or more, Fair Value	$ 637,461	$ 58,839
12 months or more, Unrealized Losses	$ (16,977)	$ (2,197)
12 months or more, Number of Securities | Security	193	14
Fair Value, Total	$ 1,061,255	$ 1,028,013
Unrealized Losses, Total	$ (22,016)	$ (18,633)
Number of Securities Total | Security	280	246
Commercial Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Sponsored Entities and Agencies [Member]
Net Unrealized Gains And Losses On Investments [Line Items]
Less than 12 months, Fair Value	$ 79,061	$ 88,169
Less than 12 months, Unrealized Losses	$ (1,089)	$ (2,122)
Less than 12 months, Number of Securities | Security	10	14
12 months or more, Fair Value	$ 27,852	$ 679
12 months or more, Unrealized Losses	$ (496)	$ (17)
12 months or more, Number of Securities | Security	6	2
Fair Value, Total	$ 106,913	$ 88,848
Unrealized Losses, Total	$ (1,585)	$ (2,139)
Number of Securities Total | Security	16	16
Obligations of State and Political Subdivisions [Member]
Net Unrealized Gains And Losses On Investments [Line Items]
Less than 12 months, Fair Value	$ 132,831	$ 364,583
Less than 12 months, Unrealized Losses	$ (852)	$ (7,121)
Less than 12 months, Number of Securities | Security	210	604
12 months or more, Fair Value	$ 77,554	$ 2,047
12 months or more, Unrealized Losses	$ (1,217)	$ (67)
12 months or more, Number of Securities | Security	160	3
Fair Value, Total	$ 210,385	$ 366,630
Unrealized Losses, Total	$ (2,069)	$ (7,188)
Number of Securities Total | Security	370	607
Corporate Debt Securities [Member]
Net Unrealized Gains And Losses On Investments [Line Items]
Less than 12 months, Fair Value	$ 4,015	$ 10,011
Less than 12 months, Unrealized Losses	$ (19)	$ (78)
Less than 12 months, Number of Securities | Security	1	3
12 months or more, Fair Value	$ 1,948	$ 5,973
12 months or more, Unrealized Losses	$ (40)	$ (50)
12 months or more, Number of Securities | Security	1	2
Fair Value, Total	$ 5,963	$ 15,984
Unrealized Losses, Total	$ (59)	$ (128)
Number of Securities Total | Security	2	5
Equity Securities [Member]
Net Unrealized Gains And Losses On Investments [Line Items]
Less than 12 months, Fair Value		$ 2,938
Less than 12 months, Unrealized Losses		$ (24)
Less than 12 months, Number of Securities | Security		2
Fair Value, Total		$ 2,938
Unrealized Losses, Total		$ (24)
Number of Securities Total | Security		2
Total Temporarily Impaired Securities [Member]
Net Unrealized Gains And Losses On Investments [Line Items]
Less than 12 months, Fair Value	$ 664,477	$ 1,492,983
Less than 12 months, Unrealized Losses	$ (7,159)	$ (26,958)
Less than 12 months, Number of Securities | Security	312	866
12 months or more, Fair Value	$ 787,063	$ 67,538
12 months or more, Unrealized Losses	$ (19,501)	$ (2,331)
12 months or more, Number of Securities | Security	368	21
Fair Value, Total	$ 1,451,540	$ 1,560,521
Unrealized Losses, Total	$ (26,660)	$ (29,289)
Number of Securities Total | Security	680	887

Loans and the Allowance for C68

Loans and the Allowance for Credit Losses - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2017USD ($)Contract	Dec. 31, 2016USD ($)Contract	Sep. 09, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Financing Receivable, Recorded Investment [Line Items]
Deferred loan (costs) and fees	$ (1,600,000)	$ 300,000
Unamortized discount on purchased loans from acquisitions	21,900,000	24,100,000
Aggregate amount of residential real estate, home equity and consumer loans classified as substandard	22,800,000	20,600,000
Internally assigned loan grades to residential real estate, home equity and consumer loans	2,500,000	3,400,000
Loans acquired with deteriorated credit quality	8,074,000	12,859,000
Allowance for loan losses	$ 45,284,000	$ 43,674,000		$ 41,710,000	$ 44,654,000
Number of restructured contracts greater than $1 million | Contract	0	0
Accruing and non accrual TDR permitted interest-only payment period	3 months
Unfunded commitments to debtors for impaired loans	$ 100,000	$ 0
Other real estate owned	5,195,000	8,206,000
Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans acquired with deteriorated credit quality	783,000	403,000
Allowance for loan losses	9,414,000	8,412,000		10,002,000	9,063,000
Commercial and Industrial [Member] | Maximum [Member]
Financing Receivable, Recorded Investment [Line Items]
Annual sales of borrowers	100,000,000
Your Community Bankshares, Inc [Member]
Financing Receivable, Recorded Investment [Line Items]
Unamortized discount on purchased loans from acquisitions	10,500,000
Loans acquired with deteriorated credit quality	4,300,000	5,700,000
Fair value of acquired loans			$ 1,012,410,000
Loans acquired accretable	700,000
Allowance for loan losses	0	0
Your Community Bankshares, Inc [Member] | Cost Recovery Method [Member]
Financing Receivable, Recorded Investment [Line Items]
Fair value of acquired loans	800,000	1,400,000
ESB Financial Corporation [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans acquired with deteriorated credit quality	3,700,000	7,200,000
Loans acquired accretable	1,000,000
Allowance for loan losses	2,000,000	1,800,000
ESB Financial Corporation [Member] | Cost Recovery Method [Member]
Financing Receivable, Recorded Investment [Line Items]
Fair value of acquired loans	3,500,000	0
Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans acquired with deteriorated credit quality	714,000	943,000
Allowance for loan losses	3,206,000	4,106,000		$ 4,582,000	$ 5,382,000
Other real estate owned	1,500,000	$ 1,600,000
Foreclosure proceedings in process on residential real estate loans	3,500,000
Residential Real Estate [Member] | Your Community Bankshares, Inc [Member] | Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Real estate owned from acquisition	$ 400,000

Loans and the Allowance for C69

Loans and the Allowance for Credit Losses - Schedule of Recorded Investment in Loans by Category (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	$ 6,341,441	$ 6,249,436
Loans held for sale	20,320	17,315
Total loans	6,361,761	6,266,751
Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	392,597	496,539
Commercial Real Estate - Improved Property [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	2,601,851	2,376,972
Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	1,125,327	1,088,118
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	2,994,448	2,873,511
Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	1,353,301	1,383,390
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	339,169	396,058
Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	$ 529,196	$ 508,359

Loans and the Allowance for C70

Loans and the Allowance for Credit Losses - Summary of Changes in Allowance for Credit Losses (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, beginning balance				$ 43,674				$ 41,710	$ 43,674	$ 41,710	$ 44,654
Allowance for loan commitments, beginning balance				571				613	571	613	455
Total beginning allowance for credit losses				44,245				42,323	44,245	42,323	45,109
Provision for loan losses									9,983	8,520	8,195
Provision for loan commitments									3	(42)	158
Total provision for credit losses	$ 2,376	$ 2,516	$ 2,383	2,711	$ 2,128	$ 2,214	$ 1,811	2,324	9,986	8,478	8,353
Charge-offs									(12,689)	(10,853)	(14,743)
Recoveries									4,316	4,297	3,604
Net charge-offs									(8,373)	(6,556)	(11,139)
Allowance for loan losses, ending balance	45,284				43,674				45,284	43,674	41,710
Allowance for loan commitments, ending balance	574				571				574	571	613
Total ending allowance for credit losses	45,858				44,245				45,858	44,245	42,323
Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, beginning balance				4,348				4,390	4,348	4,390	5,654
Allowance for loan commitments, beginning balance				151				157	151	157	194
Total beginning allowance for credit losses				4,499				4,547	4,499	4,547	5,848
Provision for loan losses									(1,259)	26	(1,265)
Provision for loan commitments									(32)	(6)	(37)
Total provision for credit losses									(1,291)	20	(1,302)
Charge-offs									(72)	(73)
Recoveries									100	5	1
Net charge-offs									28	(68)	1
Allowance for loan losses, ending balance	3,117				4,348				3,117	4,348	4,390
Allowance for loan commitments, ending balance	119				151				119	151	157
Total ending allowance for credit losses	3,236				4,499				3,236	4,499	4,547
Commercial Real Estate - Improved Property [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, beginning balance				18,628				14,748	18,628	14,748	17,573
Allowance for loan commitments, beginning balance				17				26	17	26	10
Total beginning allowance for credit losses				18,645				14,774	18,645	14,774	17,583
Provision for loan losses									4,386	4,223	1,250
Provision for loan commitments									9	(9)	16
Total provision for credit losses									4,395	4,214	1,266
Charge-offs									(2,381)	(1,886)	(4,915)
Recoveries									533	1,543	840
Net charge-offs									(1,848)	(343)	(4,075)
Allowance for loan losses, ending balance	21,166				18,628				21,166	18,628	14,748
Allowance for loan commitments, ending balance	26				17				26	17	26
Total ending allowance for credit losses	21,192				18,645				21,192	18,645	14,774
Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, beginning balance				8,412				10,002	8,412	10,002	9,063
Allowance for loan commitments, beginning balance				188				260	188	260	112
Total beginning allowance for credit losses				8,600				10,262	8,600	10,262	9,175
Provision for loan losses									2,733	1,160	3,289
Provision for loan commitments									(15)	(72)	148
Total provision for credit losses									2,718	1,088	3,437
Charge-offs									(2,669)	(3,070)	(2,785)
Recoveries									938	320	435
Net charge-offs									(1,731)	(2,750)	(2,350)
Allowance for loan losses, ending balance	9,414				8,412				9,414	8,412	10,002
Allowance for loan commitments, ending balance	173				188				173	188	260
Total ending allowance for credit losses	9,587				8,600				9,587	8,600	10,262
Deposit Overdraft [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, beginning balance				760				342	760	342	575
Total beginning allowance for credit losses				760				342	760	342	575
Provision for loan losses									1,001	1,077	391
Total provision for credit losses									1,001	1,077	391
Charge-offs									(1,293)	(884)	(846)
Recoveries									353	225	222
Net charge-offs									(940)	(659)	(624)
Allowance for loan losses, ending balance	821				760				821	760	342
Total ending allowance for credit losses	821				760				821	760	342
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, beginning balance				4,106				4,582	4,106	4,582	5,382
Allowance for loan commitments, beginning balance				9				7	9	7	9
Total beginning allowance for credit losses				4,115				4,589	4,115	4,589	5,391
Provision for loan losses									(175)	16	399
Provision for loan commitments									(2)	2	(2)
Total provision for credit losses									(177)	18	397
Charge-offs									(1,064)	(937)	(1,803)
Recoveries									339	445	604
Net charge-offs									(725)	(492)	(1,199)
Allowance for loan losses, ending balance	3,206				4,106				3,206	4,106	4,582
Allowance for loan commitments, ending balance	7				9				7	9	7
Total ending allowance for credit losses	3,213				4,115				3,213	4,115	4,589
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, beginning balance				3,998				4,763	3,998	4,763	4,078
Allowance for loan commitments, beginning balance				44				46	44	46	40
Total beginning allowance for credit losses				4,042				4,809	4,042	4,809	4,118
Provision for loan losses									1,231	1,356	2,337
Provision for loan commitments									(7)	(2)	6
Total provision for credit losses									1,224	1,354	2,343
Charge-offs									(3,989)	(3,606)	(2,892)
Recoveries									1,823	1,485	1,240
Net charge-offs									(2,166)	(2,121)	(1,652)
Allowance for loan losses, ending balance	3,063				3,998				3,063	3,998	4,763
Allowance for loan commitments, ending balance	37				44				37	44	46
Total ending allowance for credit losses	3,100				4,042				3,100	4,042	4,809
Home Equity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, beginning balance				3,422				2,883	3,422	2,883	2,329
Allowance for loan commitments, beginning balance				162				117	162	117	90
Total beginning allowance for credit losses				$ 3,584				$ 3,000	3,584	3,000	2,419
Provision for loan losses									2,066	662	1,794
Provision for loan commitments									50	45	27
Total provision for credit losses									2,116	707	1,821
Charge-offs									(1,221)	(397)	(1,502)
Recoveries									230	274	262
Net charge-offs									(991)	(123)	(1,240)
Allowance for loan losses, ending balance	4,497				3,422				4,497	3,422	2,883
Allowance for loan commitments, ending balance	212				162				212	162	117
Total ending allowance for credit losses	$ 4,709				$ 3,584				$ 4,709	$ 3,584	$ 3,000

Loans and the Allowance for C71

Loans and the Allowance for Credit Losses - Allowance for Credit Losses and Recorded Investments in Loans (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loans individually evaluated for impairment	$ 388	$ 877
Allowance for loans collectively evaluated for impairment	44,896	42,797
Allowance for loan commitments	574	571	$ 613	$ 455
Total allowance for credit losses	45,858	44,245	42,323	45,109
Individually evaluated for impairment	3,344	4,282
Collectively evaluated for impairment	6,330,023	6,232,295
Acquired with deteriorated credit quality	8,074	12,859
Total loans	6,341,441	6,249,436
Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loans collectively evaluated for impairment	3,117	4,348
Allowance for loan commitments	119	151	157	194
Total allowance for credit losses	3,236	4,499	4,547	5,848
Collectively evaluated for impairment	391,140	494,928
Acquired with deteriorated credit quality	1,457	1,611
Total loans	392,597	496,539
Commercial Real Estate - Improved Property [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loans individually evaluated for impairment	388	470
Allowance for loans collectively evaluated for impairment	20,778	18,158
Allowance for loan commitments	26	17	26	10
Total allowance for credit losses	21,192	18,645	14,774	17,583
Individually evaluated for impairment	3,344	3,012
Collectively evaluated for impairment	2,593,393	2,364,067
Acquired with deteriorated credit quality	5,114	9,893
Total loans	2,601,851	2,376,972
Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loans individually evaluated for impairment		407
Allowance for loans collectively evaluated for impairment	9,414	8,005
Allowance for loan commitments	173	188	260	112
Total allowance for credit losses	9,587	8,600	10,262	9,175
Individually evaluated for impairment		1,270
Collectively evaluated for impairment	1,124,544	1,086,445
Acquired with deteriorated credit quality	783	403
Total loans	1,125,327	1,088,118
Deposit Overdraft [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loans collectively evaluated for impairment	821	760
Total allowance for credit losses	821	760	342	575
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loans collectively evaluated for impairment	3,206	4,106
Allowance for loan commitments	7	9	7	9
Total allowance for credit losses	3,213	4,115	4,589	5,391
Collectively evaluated for impairment	1,352,587	1,382,447
Acquired with deteriorated credit quality	714	943
Total loans	1,353,301	1,383,390
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loans collectively evaluated for impairment	3,063	3,998
Allowance for loan commitments	37	44	46	40
Total allowance for credit losses	3,100	4,042	4,809	4,118
Collectively evaluated for impairment	339,163	396,049
Acquired with deteriorated credit quality	6	9
Total loans	339,169	396,058
Home Equity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loans collectively evaluated for impairment	4,497	3,422
Allowance for loan commitments	212	162	117	90
Total allowance for credit losses	4,709	3,584	$ 3,000	$ 2,419
Collectively evaluated for impairment	529,196	508,359
Total loans	$ 529,196	$ 508,359

Loans and the Allowance for C72

Loans and the Allowance for Credit Losses - Allowance for Credit Losses and Recorded Investments in Loans (Parenthetical) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Receivables [Abstract]
Troubled debt restructuring threshold	$ 1	$ 1

Loans and the Allowance for C73

Loans and the Allowance for Credit Losses - Summary of Commercial Loans by Risk Grade (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Summary of commercial loans by risk grade
Commercial loans	$ 6,296,157	$ 6,205,762
Commercial Portfolio Segment [Member]
Summary of commercial loans by risk grade
Commercial loans	4,119,775	3,961,629
Commercial Portfolio Segment [Member] | Pass [Member]
Summary of commercial loans by risk grade
Commercial loans	4,045,825	3,886,886
Commercial Portfolio Segment [Member] | Criticized [Member]
Summary of commercial loans by risk grade
Commercial loans	36,092	24,778
Commercial Portfolio Segment [Member] | Classified - Substandard [Member]
Summary of commercial loans by risk grade
Commercial loans	37,858	49,965
Commercial Portfolio Segment [Member] | Commercial Real Estate - Land and Construction [Member]
Summary of commercial loans by risk grade
Commercial loans	392,597	496,539
Commercial Portfolio Segment [Member] | Commercial Real Estate - Land and Construction [Member] | Pass [Member]
Summary of commercial loans by risk grade
Commercial loans	386,753	489,380
Commercial Portfolio Segment [Member] | Commercial Real Estate - Land and Construction [Member] | Criticized [Member]
Summary of commercial loans by risk grade
Commercial loans	2,984	4,405
Commercial Portfolio Segment [Member] | Commercial Real Estate - Land and Construction [Member] | Classified - Substandard [Member]
Summary of commercial loans by risk grade
Commercial loans	2,860	2,754
Commercial Portfolio Segment [Member] | Commercial Real Estate - Improved Property [Member]
Summary of commercial loans by risk grade
Commercial loans	2,601,851	2,376,972
Commercial Portfolio Segment [Member] | Commercial Real Estate - Improved Property [Member] | Pass [Member]
Summary of commercial loans by risk grade
Commercial loans	2,548,805	2,324,755
Commercial Portfolio Segment [Member] | Commercial Real Estate - Improved Property [Member] | Criticized [Member]
Summary of commercial loans by risk grade
Commercial loans	25,673	15,295
Commercial Portfolio Segment [Member] | Commercial Real Estate - Improved Property [Member] | Classified - Substandard [Member]
Summary of commercial loans by risk grade
Commercial loans	27,373	36,922
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
Summary of commercial loans by risk grade
Commercial loans	1,125,327	1,088,118
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] | Pass [Member]
Summary of commercial loans by risk grade
Commercial loans	1,110,267	1,072,751
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] | Criticized [Member]
Summary of commercial loans by risk grade
Commercial loans	7,435	5,078
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] | Classified - Substandard [Member]
Summary of commercial loans by risk grade
Commercial loans	$ 7,625	$ 10,289

Loans and the Allowance for C74

Loans and the Allowance for Credit Losses - Summary of Changes in Accretable Yield for Loans Acquired with Deteriorated Credit Quality (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Acquired During Period [Abstract]
Balance at beginning of period	$ 1,717	$ 1,206
Acquisitions	0	837
Reduction due to change in projected cash flows		(484)
Reclass from non-accretable difference	1,719	1,065
Transfers	(216)	(328)
Accretion	(1,496)	(579)
Balance at end of period	$ 1,724	$ 1,717

Loans and the Allowance for C75

Loans and the Allowance for Credit Losses - Summary of Age Analysis of Loan Categories (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment [Line Items]
Current	$ 6,299,397	$ 6,204,822
Total Past Due	42,044	44,614
Total Loans	6,341,441	6,249,436
Loans held for sale	20,320	17,315
90 Days or More Past Due and Accruing	2,726	3,739
Loans held for sale, current	20,320	17,315
Total loans, current	6,319,717	6,222,137
Total loans	6,361,761	6,266,751
Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	522,584	502,087
Total Past Due	6,612	6,272
Total Loans	529,196	508,359
90 Days or More Past Due and Accruing	742	626
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	2,981,893	2,864,035
Total Past Due	12,555	9,476
Total Loans	2,994,448	2,873,511
90 Days or More Past Due and Accruing	243	318
Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	1,338,240	1,365,956
Total Past Due	15,061	17,434
Total Loans	1,353,301	1,383,390
90 Days or More Past Due and Accruing	1,113	1,922
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	334,723	390,354
Total Past Due	4,446	5,704
Total Loans	339,169	396,058
90 Days or More Past Due and Accruing	608	644
Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	392,189	496,245
Total Past Due	408	294
Total Loans	392,597	496,539
Commercial Real Estate - Improved Property [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	2,589,704	2,367,790
Total Past Due	12,147	9,182
Total Loans	2,601,851	2,376,972
90 Days or More Past Due and Accruing	243	318
Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	1,121,957	1,082,390
Total Past Due	3,370	5,728
Total Loans	1,125,327	1,088,118
90 Days or More Past Due and Accruing	20	229
Non-Accrual Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	9,195	7,570
Total Past Due	27,630	24,214
Total Loans	36,825	31,784
TDRs Accruing Interest [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	6,055	7,014
Total Past Due	516	632
Total Loans	6,571	7,646
Total Impaired [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	15,250	14,584
Total Past Due	28,146	24,846
Total Loans	43,396	39,430
30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	10,034	16,395
30-59 Days Past Due [Member] | Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	2,135	2,358
30-59 Days Past Due [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	374	1,154
30-59 Days Past Due [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	4,487	6,701
30-59 Days Past Due [Member] | Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	2,466	3,674
30-59 Days Past Due [Member] | Commercial Real Estate - Improved Property [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	374	1,154
30-59 Days Past Due [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	572	2,508
30-59 Days Past Due [Member] | Non-Accrual Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	1,782	3,479
30-59 Days Past Due [Member] | TDRs Accruing Interest [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	348	342
30-59 Days Past Due [Member] | Total Impaired [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	2,130	3,821
60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	5,469	4,428
60-89 Days Past Due [Member] | Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	683	862
60-89 Days Past Due [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	1,372	363
60-89 Days Past Due [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	2,376	1,043
60-89 Days Past Due [Member] | Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	842	1,149
60-89 Days Past Due [Member] | Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	172
60-89 Days Past Due [Member] | Commercial Real Estate - Improved Property [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	1,200	363
60-89 Days Past Due [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	196	1,011
60-89 Days Past Due [Member] | Non-Accrual Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	2,033	923
60-89 Days Past Due [Member] | TDRs Accruing Interest [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	168	50
60-89 Days Past Due [Member] | Total Impaired [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	2,201	973
90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	26,541	23,791
90 Days or More Past Due [Member] | Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	3,794	3,052
90 Days or More Past Due [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	10,809	7,959
90 Days or More Past Due [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	8,198	9,690
90 Days or More Past Due [Member] | Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	1,138	881
90 Days or More Past Due [Member] | Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	236	294
90 Days or More Past Due [Member] | Commercial Real Estate - Improved Property [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	10,573	7,665
90 Days or More Past Due [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	2,602	2,209
90 Days or More Past Due [Member] | Non-Accrual Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	23,815	19,812
90 Days or More Past Due [Member] | TDRs Accruing Interest [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due		240
90 Days or More Past Due [Member] | Total Impaired [Member]
Financing Receivable, Recorded Investment [Line Items]
Total Past Due	$ 23,815	$ 20,052

Loans and the Allowance for C76

Loans and the Allowance for Credit Losses - Summary of Impaired Loans (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance, With no specific allowance recorded	$ 50,124	$ 41,119
Total impaired loans, Unpaid principal balance	52,229	49,006
Recorded Investment, With no specific allowance recorded	41,291	35,148
Total impaired loans, Recorded investment	43,396	39,430
Unpaid Principal Balance, With a specific allowance recorded	2,105	7,887
Recorded Investment, With a specific allowance recorded	2,105	4,282
Related Allowance, With a specific allowance recorded	388	877
Average recorded investment, with no related specific allowance	38,204	34,741	$ 44,326
Interest income recognized, With no related specific allowance	722	460	1,705
Average recorded investment, With a specific allowance recorded	4,700	6,226	9,475
Interest income recognized, With a specific allowance recorded	0		292
Total impaired loans, Average recorded investment	42,904	40,967	53,801
Total impaired loans, Interest income recognized	722	460	1,997
Residential Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance, With no specific allowance recorded	20,821	20,152
Recorded Investment, With no specific allowance recorded	18,982	18,305
Average recorded investment, with no related specific allowance	17,991	17,021	17,876
Interest income recognized, With no related specific allowance	252	308	862
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance, With no specific allowance recorded	1,084	884
Recorded Investment, With no specific allowance recorded	952	744
Average recorded investment, with no related specific allowance	787	909	1,199
Interest income recognized, With no related specific allowance	7	8	105
Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance, With no specific allowance recorded	5,833	4,589
Recorded Investment, With no specific allowance recorded	5,169	4,011
Average recorded investment, with no related specific allowance	4,599	3,502	2,924
Interest income recognized, With no related specific allowance	19	20	90
Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance, With no specific allowance recorded	412	1,212
Recorded Investment, With no specific allowance recorded	239	766
Average recorded investment, with no related specific allowance	460	993	2,156
Interest income recognized, With no related specific allowance	0		41
Commercial Real Estate - Improved Property [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance, With no specific allowance recorded	18,229	9,826
Recorded Investment, With no specific allowance recorded	12,863	8,141
Unpaid Principal Balance, With a specific allowance recorded	2,105	3,012
Recorded Investment, With a specific allowance recorded	2,105	3,012
Related Allowance, With a specific allowance recorded	388	470
Average recorded investment, with no related specific allowance	10,790	9,128	17,192
Interest income recognized, With no related specific allowance	436	115	437
Average recorded investment, With a specific allowance recorded	4,446	3,012	5,896
Interest income recognized, With a specific allowance recorded	0
Commercial and Industrial [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Principal Balance, With no specific allowance recorded	3,745	4,456
Recorded Investment, With no specific allowance recorded	3,086	3,181
Unpaid Principal Balance, With a specific allowance recorded		4,875
Recorded Investment, With a specific allowance recorded		1,270
Related Allowance, With a specific allowance recorded		407
Average recorded investment, with no related specific allowance	3,577	3,188	2,979
Interest income recognized, With no related specific allowance	8	9	170
Average recorded investment, With a specific allowance recorded	254	$ 3,214	3,579
Interest income recognized, With a specific allowance recorded	$ 0		$ 292

Loans and the Allowance for C77

Loans and the Allowance for Credit Losses - Recorded Investment in Non-Accrual Loans and TDRs (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Impaired [Line Items]
Non-accrual loans	$ 36,825	$ 31,784
TDRs	9,436	11,192
Accruing TDRs [Member]
Financing Receivable, Impaired [Line Items]
TDRs	6,571	7,646
Non-Accrual TDRs [Member]
Financing Receivable, Impaired [Line Items]
TDRs	2,865	3,546
Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Impaired [Line Items]
Non-accrual loans	239	766
TDRs	3	8
Commercial Real Estate - Land and Construction [Member] | Non-Accrual TDRs [Member]
Financing Receivable, Impaired [Line Items]
TDRs	3	8
Commercial Real Estate - Improved Property [Member]
Financing Receivable, Impaired [Line Items]
Non-accrual loans	13,318	9,535
TDRs	2,078	2,306
Commercial Real Estate - Improved Property [Member] | Accruing TDRs [Member]
Financing Receivable, Impaired [Line Items]
TDRs	1,650	1,618
Commercial Real Estate - Improved Property [Member] | Non-Accrual TDRs [Member]
Financing Receivable, Impaired [Line Items]
TDRs	428	688
Commercial and Industrial [Member]
Financing Receivable, Impaired [Line Items]
Non-accrual loans	2,958	4,299
TDRs	225	303
Commercial and Industrial [Member] | Accruing TDRs [Member]
Financing Receivable, Impaired [Line Items]
TDRs	128	152
Commercial and Industrial [Member] | Non-Accrual TDRs [Member]
Financing Receivable, Impaired [Line Items]
TDRs	97	151
Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Non-accrual loans	4,762	3,538
TDRs	744	770
Home Equity [Member] | Accruing TDRs [Member]
Financing Receivable, Impaired [Line Items]
TDRs	407	473
Home Equity [Member] | Non-Accrual TDRs [Member]
Financing Receivable, Impaired [Line Items]
TDRs	337	297
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Non-accrual loans	13,557	10,301
TDRs	2,081	2,314
Commercial Real Estate [Member] | Accruing TDRs [Member]
Financing Receivable, Impaired [Line Items]
TDRs	1,650	1,618
Commercial Real Estate [Member] | Non-Accrual TDRs [Member]
Financing Receivable, Impaired [Line Items]
TDRs	431	696
Residential Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Non-accrual loans	14,661	12,994
TDRs	6,201	7,523
Residential Real Estate [Member] | Accruing TDRs [Member]
Financing Receivable, Impaired [Line Items]
TDRs	4,321	5,311
Residential Real Estate [Member] | Non-Accrual TDRs [Member]
Financing Receivable, Impaired [Line Items]
TDRs	1,880	2,212
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Non-accrual loans	887	652
TDRs	185	282
Consumer [Member] | Accruing TDRs [Member]
Financing Receivable, Impaired [Line Items]
TDRs	65	92
Consumer [Member] | Non-Accrual TDRs [Member]
Financing Receivable, Impaired [Line Items]
TDRs	$ 120	$ 190

Loans and the Allowance for C78

Loans and the Allowance for Credit Losses - Recorded Investment in Non-Accrual Loans and TDRs (Parenthetical) (Detail)	Dec. 31, 2017USD ($)Borrowers	Dec. 31, 2016USD ($)Borrowers
Receivables [Abstract]
Number of borrowers with loans greater than one million | Borrowers	3	2
Borrowers with large amount of loans outstanding, minimum amount of loans per borrower	$ 1,000,000	$ 1,000,000
Borrowers with large amount of loans outstanding, net	$ 6,800,000	$ 4,300,000

Loans and the Allowance for C79

Loans and the Allowance for Credit Losses - Loans Identified as TDRs (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)Contract	Dec. 31, 2016USD ($)Contract
Financing Receivable, Modifications [Line Items]
Number of Modifications | Contract	13	21
Pre-Modification Outstanding Recorded Investment	$ 664	$ 445
Post-Modification Outstanding Recorded Investment	$ 617	$ 400
Commercial Real Estate - Improved Property [Member]
Financing Receivable, Modifications [Line Items]
Number of Modifications | Contract	2
Pre-Modification Outstanding Recorded Investment	$ 345
Post-Modification Outstanding Recorded Investment	$ 331
Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Modifications | Contract	1	2
Pre-Modification Outstanding Recorded Investment	$ 64	$ 125
Post-Modification Outstanding Recorded Investment	$ 58	$ 120
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Modifications | Contract	2
Pre-Modification Outstanding Recorded Investment	$ 345
Post-Modification Outstanding Recorded Investment	$ 331
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Modifications | Contract	3	4
Pre-Modification Outstanding Recorded Investment	$ 144	$ 178
Post-Modification Outstanding Recorded Investment	$ 137	$ 166
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Modifications | Contract	5	14
Pre-Modification Outstanding Recorded Investment	$ 43	$ 98
Post-Modification Outstanding Recorded Investment	$ 30	$ 74
Home Equity [Member]
Financing Receivable, Modifications [Line Items]
Number of Modifications | Contract	2	1
Pre-Modification Outstanding Recorded Investment	$ 68	$ 44
Post-Modification Outstanding Recorded Investment	$ 61	$ 40

Loans and the Allowance for C80

Loans and the Allowance for Credit Losses - TDRs Defaulted Later Restructured (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)Defaults	Dec. 31, 2016USD ($)Defaults
Financing Receivable, Modifications [Line Items]
Number of Defaults | Defaults	3	1
Recorded Investment | $	$ 135	$ 16
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Defaults | Defaults	2
Recorded Investment | $	$ 128
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Defaults | Defaults		1
Recorded Investment | $		$ 16
Home Equity [Member]
Financing Receivable, Modifications [Line Items]
Number of Defaults | Defaults	1
Recorded Investment | $	$ 7

Loans and the Allowance for C81

Loans and the Allowance for Credit Losses - Recognition of Interest Income on Impaired Loans (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Receivables [Abstract]
Average impaired loans	$ 42,904	$ 40,967	$ 53,801
Amount of contractual interest income on impaired loans	3,089	2,747	3,061
Amount of interest income recognized on impaired loans	$ 722	$ 460	$ 1,997

Loans and the Allowance for C82

Loans and the Allowance for Credit Losses - Summary of Other Real Estate Owned and Repossessed Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Receivables [Abstract]
Other real estate owned	$ 5,195	$ 8,206
Repossessed assets	102	140
Total other real estate owned and repossessed assets	$ 5,297	$ 8,346

Premises and Equipment - Schedu

Premises and Equipment - Schedule of Premises and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Land and improvements	$ 41,209	$ 43,059
Buildings and improvements	141,960	136,546
Furniture and equipment	75,816	72,050
Total cost	258,985	251,655
Accumulated depreciation and amortization	(128,263)	(118,358)
Total premises and equipment, net	$ 130,722	$ 133,297

Premises and Equipment - Additi

Premises and Equipment - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense charged	$ 10.4	$ 9.2	$ 8.1
Rent expense under leases	$ 4.2	$ 3.5	$ 3.1

Premises and Equipment - Future

Premises and Equipment - Future Minimum Lease Payments Under Non-cancellable Leases (Detail)	Dec. 31, 2017USD ($)
Property, Plant and Equipment [Abstract]
2,018	$ 4,240,000
2,019	3,713,000
2,020	3,548,000
2,021	3,089,000
2,022	2,294,000
2023 and thereafter	13,690,000
Total	$ 30,574,000

Goodwill and Other Intangible86

Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands	Sep. 09, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Intangible Assets Goodwill And Other Assets [Line Items]
Goodwill		$ 573,900	$ 573,800
Other intangible assets		15,318	19,384
Amortization of core deposit and customer list intangible assets		4,100	2,900	$ 2,400
Amortization of intangible assets		4,940	3,598	$ 3,136
Amortization expense expected to be recognized in year one		3,543
Amortization expense expected to be recognized in year two		3,037
Amortization expense expected to be recognized in year three		2,564
Your Community Bankshares, Inc [Member]
Intangible Assets Goodwill And Other Assets [Line Items]
Goodwill acquired	$ 93,033	93,033
Your Community Bankshares, Inc [Member] | Core Deposits [Member]
Intangible Assets Goodwill And Other Assets [Line Items]
Intangible assets acquired		12,000
YCB and ESB [Member] | Noncompete Agreements [Member]
Intangible Assets Goodwill And Other Assets [Line Items]
Amortization of intangible assets		900	$ 700
Amortization expense expected to be recognized in year one		600
Amortization expense expected to be recognized in year two		200
Amortization expense expected to be recognized in year three		$ 0
Minimum [Member]
Intangible Assets Goodwill And Other Assets [Line Items]
Intangible asset, useful life		10 years
Minimum [Member] | YCB and ESB [Member] | Noncompete Agreements [Member]
Intangible Assets Goodwill And Other Assets [Line Items]
Intangible asset, useful life		1 year
Maximum [Member]
Intangible Assets Goodwill And Other Assets [Line Items]
Intangible asset, useful life		16 years
Maximum [Member] | YCB and ESB [Member] | Noncompete Agreements [Member]
Intangible Assets Goodwill And Other Assets [Line Items]
Intangible asset, useful life		4 years

Goodwill and Other Intangible87

Goodwill and Other Intangible Assets - WesBanco's Capitalized Other Intangible Assets and Related Accumulated Amortization (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Other intangible assets:
Gross carrying amount	$ 37,725	$ 37,725
Accumulated amortization	(22,407)	(18,341)
Net carrying amount of other intangible assets	$ 15,318	$ 19,384

Goodwill and Other Intangible88

Goodwill and Other Intangible Assets - Schedule of Future Amortization on Intangible Assets (Detail) $ in Thousands	Dec. 31, 2017USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2,018	$ 3,543
2,019	3,037
2,020	2,564
2,021	2,122
2,022	$ 1,701

Investments in Limited Partne89

Investments in Limited Partnerships - Additional Information (Detail) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017USD ($)	Dec. 31, 2017USD ($)Partnership	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Equity Method Investments and Joint Ventures [Abstract]
Amount invested in partnerships	$ 15,600	$ 15,600	$ 14,300
Unfunded equity commitments in other liabilities	10,700	10,700	8,200
Partnerships losses and impairment			900	$ 600
Tax benefits including low-income housing and historic tax credits		1,600	800	500
Partnerships losses and impairment	300	$ 1,500
Number of limited partnerships held | Partnership		7
Investment in partnership recorded in other assets	$ 5,400	$ 5,400	5,200
Partnership gains (losses) under equity method		$ 47	$ 19	$ (1)

Certificates of Deposit - Addit

Certificates of Deposit - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Debt Disclosure [Abstract]
Certificates of deposit in denominations of $100 thousand or more	$ 581.6	$ 681.5
Interest expense on certificates of deposit of $100 thousand or more	$ 4.4	$ 5	$ 4.9

Certificates of Deposit - Sched

Certificates of Deposit - Schedule of Maturities of Total Certificates of Deposit (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Time Deposits, Fiscal Year Maturity [Abstract]
2,018	$ 736,435
2,019	218,392
2,020	154,186
2,021	83,079
2,022	49,564
2023 and thereafter	35,401
Total	$ 1,277,057	$ 1,495,822

FHLB and Other Short-Term Bor92

FHLB and Other Short-Term Borrowings - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Federal Home Loan Bank Advances By Branch Of FHLB Bank And Other Borrowings [Line Items]
Borrowings	$ 948,203,000	$ 968,946,000
Weighted-average rate, Total	1.57%	1.19%
FHLB stock owned by WesBanco pledged as collateral on these advances	$ 45,900,000	$ 46,400,000
Remaining maximum borrowing capacity	1,800,000,000	1,700,000,000
Other short term borrowings	184,805,000	199,376,000
Securities sold under agreements to repurchase	$ 159,800,000	$ 141,400,000
Securities sold under agreements to repurchase, weighted average interest rate	0.67%	0.38%
Federal funds purchased	$ 25,000,000	$ 58,000,000
Securities sold under agreements to repurchase, interest rate	1.60%	0.85%
Outstanding balance	$ 0	$ 0
Revolving Credit Facility [Member]
Federal Home Loan Bank Advances By Branch Of FHLB Bank And Other Borrowings [Line Items]
Revolving line of credit accrued interest at LIBOR rate, provides for aggregate outstanding borrowings	$ 25,000,000
Initiation date of revolving credit facility	Sep. 30, 2017

FHLB and Other Short-Term Bor93

FHLB and Other Short-Term Borrowings - Schedule of Aggregate Annual Maturities and Weighted-Average Interest Rates of FHLB Borrowing (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Federal Home Loan Bank, Advances, Fiscal Year Maturity [Abstract]
2,018	$ 540,770
2,019	334,104
2,020	71,064
2,021	294
2,022	0
2023 and thereafter	1,971
Total	$ 948,203	$ 968,946
2,018	1.40%
2,019	1.78%
2,020	1.96%
2,021	5.22%
2,022	0.00%
2023 and thereafter	1.42%
Total	1.57%

Subordinated Debt and Junior 94

Subordinated Debt and Junior Subordinated Debt - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2017USD ($)
Trust Preferred Securities [Line Items]
Description of deferment period for payment of interest on junior subordinated debt under trust	20 consecutive quarterly periods
Minimum assets to continue counting existing trust preferred securities	$ 15,000,000,000
Your Community Bankshares, Inc [Member]
Trust Preferred Securities [Line Items]
Subordinated debt outstanding	$ 25,800,000
Debt maturity date	Dec. 15, 2025
Fixed interest rate	6.25%
Debt callable date	Dec. 15, 2020
Variable rate based on the three-month LIBOR plus	4.59%

Subordinated Debt and Junior 95

Subordinated Debt and Junior Subordinated Debt - Schedule of Junior Subordinated Debt by Trusts (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)
Trust Preferred Securities [Line Items]
Trust Preferred Securities	$ 134,291
Common Securities	4,273
Junior Subordinated Debt	138,564
WesBanco Capital Trust II [Member]
Trust Preferred Securities [Line Items]
Trust Preferred Securities	13,000
Common Securities	410
Junior Subordinated Debt	$ 13,410
Stated Maturity Date	Jun. 30, 2033
Optional Redemption Date	Jun. 30, 2008
WesBanco Capital Statutory Trust III [Member]
Trust Preferred Securities [Line Items]
Trust Preferred Securities	$ 17,000
Common Securities	526
Junior Subordinated Debt	$ 17,526
Stated Maturity Date	Jun. 26, 2033
Optional Redemption Date	Jun. 26, 2008
WesBanco Capital Trust IV [Member]
Trust Preferred Securities [Line Items]
Trust Preferred Securities	$ 20,000
Common Securities	619
Junior Subordinated Debt	$ 20,619
Stated Maturity Date	Jun. 17, 2034
Optional Redemption Date	Jun. 17, 2009
WesBanco Capital Trust V [Member]
Trust Preferred Securities [Line Items]
Trust Preferred Securities	$ 20,000
Common Securities	619
Junior Subordinated Debt	$ 20,619
Stated Maturity Date	Jun. 17, 2034
Optional Redemption Date	Jun. 17, 2009
WesBanco Capital Trust VI [Member]
Trust Preferred Securities [Line Items]
Trust Preferred Securities	$ 15,000
Common Securities	464
Junior Subordinated Debt	$ 15,464
Stated Maturity Date	Mar. 17, 2035
Optional Redemption Date	Mar. 17, 2010
Oak Hill Capital Trust 2 [Member]
Trust Preferred Securities [Line Items]
Trust Preferred Securities	$ 5,000
Common Securities	155
Junior Subordinated Debt	$ 5,155
Stated Maturity Date	Oct. 18, 2034
Optional Redemption Date	Oct. 18, 2009
Oak Hill Capital Trust 3 [Member]
Trust Preferred Securities [Line Items]
Trust Preferred Securities	$ 8,000
Common Securities	248
Junior Subordinated Debt	$ 8,248
Stated Maturity Date	Oct. 18, 2034
Optional Redemption Date	Oct. 18, 2009
Oak Hill Capital Trust 4 [Member]
Trust Preferred Securities [Line Items]
Trust Preferred Securities	$ 5,000
Common Securities	155
Junior Subordinated Debt	$ 5,155
Stated Maturity Date	Jun. 30, 2035
Optional Redemption Date	Jun. 30, 2015
Community Bank Shares Statutory Trust I [Member]
Trust Preferred Securities [Line Items]
Trust Preferred Securities	$ 6,252
Common Securities	217
Junior Subordinated Debt	$ 6,469
Stated Maturity Date	Jun. 17, 2034
Optional Redemption Date	Jun. 17, 2014
Community Bank Shares Statutory Trust II [Member]
Trust Preferred Securities [Line Items]
Trust Preferred Securities	$ 8,476
Common Securities	310
Junior Subordinated Debt	$ 8,786
Stated Maturity Date	Jun. 15, 2036
Optional Redemption Date	Jun. 15, 2016
First Federal Statutory Trust II [Member]
Trust Preferred Securities [Line Items]
Trust Preferred Securities	$ 8,419
Common Securities	310
Junior Subordinated Debt	$ 8,729
Stated Maturity Date	Mar. 22, 2037
Optional Redemption Date	Mar. 15, 2017
First Federal Statutory Trust III [Member]
Trust Preferred Securities [Line Items]
Trust Preferred Securities	$ 8,144
Common Securities	240
Junior Subordinated Debt	$ 8,384
Stated Maturity Date	Jun. 24, 2038
Optional Redemption Date	Jun. 24, 2018

Subordinated Debt and Junior 96

Subordinated Debt and Junior Subordinated Debt - Schedule of Junior Subordinated Debt by Trusts (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2017
WesBanco Capital Trust II [Member]
Trust Preferred Securities [Line Items]
Variable rate based on the three-month LIBOR plus	3.15%
Variable rate based on the three-month LIBOR plus, current rate	4.84%
WesBanco Capital Statutory Trust III [Member]
Trust Preferred Securities [Line Items]
Variable rate based on the three-month LIBOR plus	3.10%
Variable rate based on the three-month LIBOR plus, current rate	4.77%
WesBanco Capital Trust IV [Member]
Trust Preferred Securities [Line Items]
Variable rate based on the three-month LIBOR plus	2.65%
Variable rate based on the three-month LIBOR plus, current rate	4.25%
WesBanco Capital Trust V [Member]
Trust Preferred Securities [Line Items]
Variable rate based on the three-month LIBOR plus	2.65%
Variable rate based on the three-month LIBOR plus, current rate	4.25%
WesBanco Capital Trust VI [Member]
Trust Preferred Securities [Line Items]
Variable rate based on the three-month LIBOR plus	1.77%
Variable rate based on the three-month LIBOR plus, current rate	3.37%
Oak Hill Capital Trust 2 [Member]
Trust Preferred Securities [Line Items]
Variable rate based on the three-month LIBOR plus	2.40%
Variable rate based on the three-month LIBOR plus, current rate	3.75%
Oak Hill Capital Trust 3 [Member]
Trust Preferred Securities [Line Items]
Variable rate based on the three-month LIBOR plus	2.30%
Variable rate based on the three-month LIBOR plus, current rate	3.65%
Oak Hill Capital Trust 4 [Member]
Trust Preferred Securities [Line Items]
Variable rate based on the three-month LIBOR plus	1.60%
Variable rate based on the three-month LIBOR plus, current rate	3.29%
Community Bank Shares Statutory Trust I [Member]
Trust Preferred Securities [Line Items]
Variable rate based on the three-month LIBOR plus	2.65%
Variable rate based on the three-month LIBOR plus, current rate	4.25%
Community Bank Shares Statutory Trust II [Member]
Trust Preferred Securities [Line Items]
Variable rate based on the three-month LIBOR plus	1.70%
Variable rate based on the three-month LIBOR plus, current rate	3.29%
First Federal Statutory Trust II [Member]
Trust Preferred Securities [Line Items]
Variable rate based on the three-month LIBOR plus	1.60%
Variable rate based on the three-month LIBOR plus, current rate	3.19%
First Federal Statutory Trust III [Member]
Trust Preferred Securities [Line Items]
Fixed interest rate	8.00%
Debt callable year	Jun. 24, 2018

Derivatives and Hedging Activ97

Derivatives and Hedging Activities - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2017USD ($)Derivative	Dec. 31, 2016USD ($)Derivative	Dec. 31, 2015USD ($)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Aggregate notional amount	$ 298,200,000	$ 206,900,000
Net gain (loss) on change in fair value	(371,000)	$ 451,000	$ 23,000
Collateral posted with market value on liability positions with credit risk-related contingent features	$ 3,000,000
Interest Rate Swaps [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of interest rate swaps | Derivative	39	24
Net gain (loss) on change in fair value	$ (400)	$ 500	3,000
Income (loss) on derivative instrument not designated hedges	$ 2,300,000	$ 2,500,000	$ 200,000

Derivatives and Hedging Activ98

Derivatives and Hedging Activities - Summary of Fair Values of Derivative Instruments on Balance Sheets (Detail) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Notional or Contractual Amount	$ 298,200,000	$ 206,900,000
Asset Derivatives	7,400,000	5,675,000
Liability Derivatives	7,374,000	5,322,000
Interest Rate Swaps [Member] | Loan Swaps [Member]
Derivatives, Fair Value [Line Items]
Notional or Contractual Amount	298,223,000	206,923,000
Asset Derivatives	7,351,000	5,596,000
Liability Derivatives	7,345,000	5,199,000
Interest Rate Loan Commitments [Member] | Other Contract [Member]
Derivatives, Fair Value [Line Items]
Notional or Contractual Amount	20,319,000	19,453,000
Asset Derivatives	49,000
Liability Derivatives		123,000
Best Efforts Forward Delivery Commitments [Member] | Other Contract [Member]
Derivatives, Fair Value [Line Items]
Notional or Contractual Amount	2,905,000	19,453,000
Asset Derivatives		$ 79,000
Liability Derivatives	6,000
Forward TBA Contracts [Member] | Other Contract [Member]
Derivatives, Fair Value [Line Items]
Notional or Contractual Amount	31,750,000
Liability Derivatives	$ 23,000

Derivatives and Hedging Activ99

Derivatives and Hedging Activities - Summary of Effect of Derivative Instruments on Income Statement (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Total gain (loss) on derivative financial instruments	$ (371)	$ 451	$ 23
Interest Rate Swaps [Member] | Other Income [Member]
Derivatives, Fair Value [Line Items]
Total gain (loss) on derivative financial instruments	(391)	495	3
Interest Rate Loan Commitments [Member] | Mortgage Banking Income [Member]
Derivatives, Fair Value [Line Items]
Total gain (loss) on derivative financial instruments	49	(123)	15
Best Efforts Forward Delivery Commitments [Member] | Mortgage Banking Income [Member]
Derivatives, Fair Value [Line Items]
Total gain (loss) on derivative financial instruments	(6)	$ 79	$ 5
Forward TBA Contracts [Member] | Mortgage Banking Income [Member]
Derivatives, Fair Value [Line Items]
Total gain (loss) on derivative financial instruments	$ (23)

Employee Benefit Plans - Additi

Employee Benefit Plans - Additional Information (Detail) - USD ($)	May 16, 2017	Nov. 18, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Apr. 20, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Benefits bases on years of service and compensation, years			5 years
Future defined benefit plan estimated service and interest cost			$ 1,000,000
Future amortization of net loss			2,800,000
Future net periodic pension costs			$ 26,000
Average remaining service period of unrecognized net losses			9 years
Maximum amount of pension plan invested			5.00%
Maximum common stock percentage of market value of investee			5.00%
Maximum percentage of investment in bonds or notes			5.00%
Maximum period for invested in bonds or notes issued			20 years
Number of equity shares			55,300	55,300
Common stock fair market value			$ 2,200,000	$ 2,400,000
Expected voluntary contribution for the year 2018			5,000,000
Contribution of pension fund			5,000,000	5,750,000	$ 7,500,000
Accumulated benefit obligation			119,559,000	104,775,000
Fair value of plan asset			142,422,000	121,597,000	113,292,000
Net periodic benefit income			$ 2,571,000	$ 3,220,000	$ 3,695,000
Discount rate			4.46%	4.74%	4.33%
Expected long-term rate of return			6.30%	6.79%	7.00%
Eligible employee contributions specified percentage one			3.00%	3.00%	3.00%
Eligible employee contributions specified percentage two			2.00%	2.00%	2.00%
ESOP			$ 0	$ 0	$ 0
Eligibility percentage of employee contributions			100.00%	100.00%	100.00%
Eligibility percentage of employee contributions			50.00%	50.00%	50.00%
Compensation expense for Annual Bonus			$ 1,800,000	$ 1,600,000	$ 1,300,000
Stock options granted to selected participants			117,550
Stock options granted to selected participants exercise price per share			$ 38.88
Options grant expired				7 years
Total intrinsic value of options exercised			$ 700,000	$ 1,200,000
Cash received from stock option exercised			1,500,000	2,500,000
Tax benefit realized from stock options exercised			300,000	400,000
Total intrinsic value of the outstanding shares			2,500,000
Total intrinsic value of the shares exercisable			2,400,000
Total Assets			9,816,178,000	9,790,877,000
Shareholder Return Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense for the KSOP/Compensation expense for the stock option component of the Plan			$ 200,000	$ 100,000	0
Expense recognition period			3 years
Number of shares granted		12,000	0	0
Restricted shares vesting period		3 years
Percentage of shares earned by participants		200.00%
Total shareholder return measurement period		3 years
Grant date fair value			$ 32.90
Total unrecognized compensation expense			$ 500,000
KSOP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares held by KSOP			495,090
Total expense for the KSOP/Compensation expense for the stock option component of the Plan			$ 3,300,000	$ 2,800,000	2,500,000
Future issuance under equity compensation plans			415,052	445,978
Equity Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Future issuance under equity compensation plans			912,192	117,266
Additional ccommon stock for issuance						1,000,000
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense for the KSOP/Compensation expense for the stock option component of the Plan			$ 600,000	$ 500,000	$ 500,000
Options grant expired			7 years		7 years
Total unrecognized compensation expense related to non-vested stock option grants			$ 400,000
Expense recognition period			1 year
Stock Option [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options grant expired			10 years
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total expense for the KSOP/Compensation expense for the stock option component of the Plan			$ 2,100,000	$ 1,400,000	$ 1,200,000
Expense recognition period			1 year 6 months
Number of shares granted			79,324
Fair value of restricted stock granted			$ 38.88
Total unrecognized compensation expense related to non-vested restricted stock grants			$ 3,900,000
Grant date fair value			$ 34.91	$ 31.40
Selected Participants Including Certain Executive Officers [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted to selected participants	117,550
Stock options granted to selected participants exercise price per share	$ 38.88
Performance Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted			9,003
Restricted shares vesting period			3 years
Performance Based Restricted Stock [Member] | Vesting on May 16, 2021 after the Completion of the Three-year Performance Period [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			50.00%
Performance Based Restricted Stock [Member] | Vesting on May 16, 2022 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			50.00%
Performance Based Restricted Stock [Member] | Maximum [Member] | National Peer Group of Financial Institutions [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Assets			$ 15,000,000,000
Performance Based Restricted Stock [Member] | Minimum [Member] | National Peer Group of Financial Institutions [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Assets			$ 9,000,000,000
Service Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted			70,321
Restricted shares vesting period			36 months
Fair value of restricted stock granted			$ 38.88
Pentegra Defined Benefit Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected voluntary contribution for the year 2018			$ 200,000
Spinning off of asset cost			2,800,000
Accumulated benefit obligation			9,400,000
Fair value of plan asset			8,700,000
Net periodic benefit income			$ 85,000
Discount rate			3.71%
Expected long-term rate of return			5.62%

Employee Benefit Plans - Summar

Employee Benefit Plans - Summary of Benefit Obligations and Funded Status of the Plan (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Compensation Related Costs [Abstract]
Accumulated benefit obligation at end of year	$ 119,559	$ 104,775
Change in projected benefit obligation:
Projected benefit obligation at beginning of year	115,458	109,400
Service cost	2,578	2,799	$ 3,355
Interest cost	4,393	5,094	4,870
Actuarial (gain) loss	12,172	2,569
Acquisition		1,392
Benefits paid	(4,294)	(5,796)
Projected benefit obligation at end of year	130,307	115,458	109,400
Change in fair value of plan assets:
Fair value of plan assets at beginning of year	121,597	113,292
Actual return on plan assets	20,119	7,125
Employer contribution	5,000	5,750	7,500
Acquisition		1,226
Benefits paid	(4,294)	(5,796)
Fair value of plan assets at end of year	142,422	121,597	$ 113,292
Amounts recognized in the statement of financial position:
Funded status	12,115	6,139
Net amounts recognized as receivable pension costs in the consolidated balance sheets	12,115	6,139
Amounts recognized in accumulated other comprehensive income consist of:
Unrecognized prior service cost	104	130
Unrecognized net loss	24,336	27,857
Net amounts recognized in accumulated other comprehensive income (before tax)	$ 24,440	$ 27,987
Weighted average assumptions used to determine benefit obligations:
Discount rate	3.81%	4.46%
Rate of compensation increase	3.70%	3.74%
Expected long-term return on assets	6.30%	6.30%

Employee Benefit Plans - Compon

Employee Benefit Plans - Components of and Weighted-Average Assumptions Used in Determining Net Periodic Benefit Costs (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Components of net periodic benefit cost:
Service cost-benefits earned during year	$ 2,578	$ 2,799	$ 3,355
Interest cost on projected benefit obligation	4,393	5,094	4,870
Expected return on plan assets	(7,647)	(7,719)	(7,735)
Amortization of prior service cost	26	26	26
Amortization of net loss	3,221	3,020	3,179
Net periodic pension cost	2,571	3,220	3,695
Other changes in plan assets and benefit obligations recognized in other comprehensive income:
Net (gain) loss for period	(300)	3,329	(5,106)
Amortization of prior service cost	(26)	(26)	(26)
Amortization of net loss	(3,221)	(3,020)	(3,179)
Total recognized in other comprehensive income	(3,547)	283	(8,311)
Total recognized in net periodic pension cost and other comprehensive income	$ (976)	$ 3,503	$ (4,616)
Weighted-average assumptions used to determine net periodic pension cost:
Discount rate	4.46%	4.74%	4.33%
Rate of compensation increase	3.74%	3.82%	3.77%
Expected long-term return on assets	6.30%	6.79%	7.00%

Employee Benefit Plans - Sum103

Employee Benefit Plans - Summary of Weighted-Average Asset Allocations by Asset Category (Detail)	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Assets Target Allocations [Line Items]
Total	100.00%	100.00%
Equity Securities [Member]
Defined Benefit Plan Assets Target Allocations [Line Items]
Total	5.00%	62.00%
Equity Securities [Member] | Minimum [Member]
Defined Benefit Plan Assets Target Allocations [Line Items]
Target Allocation	55.00%
Equity Securities [Member] | Maximum [Member]
Defined Benefit Plan Assets Target Allocations [Line Items]
Target Allocation	75.00%
Debt Securities [Member]
Defined Benefit Plan Assets Target Allocations [Line Items]
Total	32.00%	35.00%
Debt Securities [Member] | Minimum [Member]
Defined Benefit Plan Assets Target Allocations [Line Items]
Target Allocation	25.00%
Debt Securities [Member] | Maximum [Member]
Defined Benefit Plan Assets Target Allocations [Line Items]
Target Allocation	55.00%
Cash and Cash Equivalents [Member]
Defined Benefit Plan Assets Target Allocations [Line Items]
Total	4.00%	35.00%
Cash and Cash Equivalents [Member] | Minimum [Member]
Defined Benefit Plan Assets Target Allocations [Line Items]
Target Allocation	0.00%
Cash and Cash Equivalents [Member] | Maximum [Member]
Defined Benefit Plan Assets Target Allocations [Line Items]
Target Allocation	5.00%

Employee Benefit Plans - Fair V

Employee Benefit Plans - Fair Values of the WesBanco's Pension Plan Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit pension plan assets	$ 142,400	$ 120,363
Registered Investment Companies [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit pension plan assets	39,799	21,935
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit pension plan assets	64,128	60,144
Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit pension plan assets	16,147	18,110
Municipal Obligations [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit pension plan assets	3,004	2,998
Residential Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Sponsored Entities and Agencies [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit pension plan assets	19,322	17,176
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit pension plan assets	103,927	82,079
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Registered Investment Companies [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit pension plan assets	39,799	21,935
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit pension plan assets	64,128	60,144
Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit pension plan assets	38,473	38,284
Significant Other Observable Inputs (Level 2) [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit pension plan assets	16,147	18,110
Significant Other Observable Inputs (Level 2) [Member] | Municipal Obligations [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit pension plan assets	3,004	2,998
Significant Other Observable Inputs (Level 2) [Member] | Residential Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Sponsored Entities and Agencies [Member]
Defined Benefit Plan Disclosure [Line Items]
Total defined benefit pension plan assets	$ 19,322	$ 17,176

Employee Benefit Plans - Fai105

Employee Benefit Plans - Fair Values of the WesBanco's Pension Plan Assets (Parenthetical) (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Compensation Related Costs [Abstract]
Net assets available for benefits	$ 142,422	$ 121,597	$ 113,292

Employee Benefit Plans - Estima

Employee Benefit Plans - Estimated Benefits to be Paid in Each of Next Five Years and in the Aggregate for the Five Years Thereafter (Detail) $ in Thousands	Dec. 31, 2017USD ($)
Compensation Related Costs [Abstract]
2,018	$ 4,014
2,019	4,524
2,020	4,839
2,021	5,277
2,022	5,599
2023 to 2027	$ 33,631

Employee Benefit Plans - Signif

Employee Benefit Plans - Significant Assumptions Used in Calculating the Fair Value of the Grants (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Compensation Related Costs [Abstract]
Weighted-average life	5 years 2 months 12 days	5 years 1 month 6 days	4 years 10 months 25 days
Risk-free interest rate	1.91%	1.43%	1.54%
Dividend yield	2.67%	2.97%	2.91%
Volatility factor	21.47%	23.92%	26.27%
Fair value of the grants	$ 6.02	$ 5.09	$ 5.57

Employee Benefit Plans - Sum108

Employee Benefit Plans - Summary of Activity for the Stock Option Component of the Incentive Plan (Detail)	12 Months Ended
	Dec. 31, 2017$ / sharesshares
Compensation Related Costs [Abstract]
Number of options, Outstanding at beginning of the year | shares	276,122
Number of options, Granted during the year | shares	117,550
Number of options, Exercised during the year | shares	(53,584)
Number of options, Forfeited or expired during the year | shares	(3,400)
Number of options, Outstanding at end of the year | shares	336,688
Number of options, Exercisable at year end | shares	277,913
Weighted average exercise price per share, Outstanding at beginning of the year | $ / shares	$ 29.71
Weighted average exercise price per share, Granted during the year | $ / shares	38.88
Weighted average exercise price per share, Exercised during the year | $ / shares	27.96
Weighted average exercise price per share, Forfeited or expired during the year | $ / shares	28.83
Weighted average exercise price per share, Outstanding at end of the year | $ / shares	33.20
Weighted average exercise price per share, Exercisable at year end | $ / shares	$ 31.99

Employee Benefit Plans - Sum109

Employee Benefit Plans - Summary of Average Remaining Life of the Stock Options (Detail)	12 Months Ended
	Dec. 31, 2017$ / sharesshares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercisable at Year End | shares	277,913
Exercise Price Range Per Share Minimum	$ 19.76
Exercise Price Range Per Share Maximum	$ 38.88
Options Outstanding | shares	336,688
Weighted Average Exercise Price	$ 33.20
Weighted Avg. Remaining Contractual Life in Years	4 years 11 months 23 days
2011 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercisable at Year End | shares	2,750
Exercise Price Range Per Share Maximum	$ 19.76
Options Outstanding | shares	2,750
Weighted Average Exercise Price	$ 19.76
Weighted Avg. Remaining Contractual Life in Years	4 months 17 days
2012 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercisable at Year End | shares	6,750
Exercise Price Range Per Share Maximum	$ 20.02
Options Outstanding | shares	6,750
Weighted Average Exercise Price	$ 20.02
Weighted Avg. Remaining Contractual Life in Years	1 year 4 months 13 days
2013 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercisable at Year End | shares	24,000
Exercise Price Range Per Share Maximum	$ 25
Options Outstanding | shares	24,000
Weighted Average Exercise Price	$ 25
Weighted Avg. Remaining Contractual Life in Years	2 years 4 months 13 days
2014 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercisable at Year End | shares	40,550
Exercise Price Range Per Share Maximum	$ 28.79
Options Outstanding | shares	40,550
Weighted Average Exercise Price	$ 28.79
Weighted Avg. Remaining Contractual Life in Years	3 years 4 months 20 days
2015 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercisable at Year End | shares	59,488
Exercise Price Range Per Share Maximum	$ 31.58
Options Outstanding | shares	59,488
Weighted Average Exercise Price	$ 31.58
Weighted Avg. Remaining Contractual Life in Years	4 years 5 months 1 day
2016 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercisable at Year End | shares	85,600
Exercise Price Range Per Share Maximum	$ 32.37
Options Outstanding | shares	85,600
Weighted Average Exercise Price	$ 32.37
Weighted Avg. Remaining Contractual Life in Years	5 years 4 months 24 days
Stock Option Plan Two Thousand And Seventeen [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercisable at Year End | shares	58,775
Exercise Price Range Per Share Maximum	$ 38.88
Options Outstanding | shares	117,550
Weighted Average Exercise Price	$ 38.88
Weighted Avg. Remaining Contractual Life in Years	6 years 4 months 6 days

Employee Benefit Plans - Schedu

Employee Benefit Plans - Schedule of Activity for the Restricted Stock Component of the Plan (Detail) - Restricted Stock [Member]	12 Months Ended
	Dec. 31, 2017$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock Beginning Balance | shares	170,482
Restricted Stock, Granted | shares	79,324
Restricted Stock, Vested | shares	(42,029)
Restricted Stock, Forfeited | shares	(4,068)
Restricted Stock, Dividend reinvestment | shares	4,681
Restricted Stock Ending Balance | shares	208,390
Weighted Average Grant Date Fair Value Per Share Beginning Balance | $ / shares	$ 31.40
Weighted Average Grant Date Fair Value Per Share, Granted | $ / shares	38.88
Weighted Average Grant Date Fair Value Per Share, Vested | $ / shares	29.13
Weighted Average Grant Date Fair Value Per Share, Forfeited | $ / shares	31.34
Weighted Average Grant Date Fair Value Per Share, Dividend reinvestment | $ / shares	40.65
Weighted Average Grant Date Fair Value Per Share Ending Balance | $ / shares	$ 34.91

Other Operating Expenses - Sche

Other Operating Expenses - Schedule of Other Operating Expenses (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Costs and Expenses [Abstract]
Franchise and other miscellaneous taxes	$ 8,423	$ 6,825	$ 5,924
Consulting, regulatory and advisory fees	6,857	6,270	4,959
ATM and electronic banking interchange expenses	4,510	4,297	4,463
Postage and courier expenses	3,879	3,306	3,720
Supplies	3,033	2,919	2,841
Legal fees	2,781	2,406	2,418
Communications	2,487	1,800	1,537
Other real estate owned and foreclosure expenses	1,097	1,210	546
Other	12,263	11,967	12,479
Total other operating expenses	$ 45,330	$ 41,000	$ 38,887

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Line Items]
Federal statutory tax rate		35.00%	35.00%	35.00%
Net deferred tax asset resulted in additional income tax expense		$ 12,800,000
Valuation allowance of deferred tax assets		100,000	$ 100,000
Alternative minimum tax credits		5,200,000
Deferred tax assets net operating loss carryforwards		6,062,000	12,020,000
Qualifying and non-qualifying tax bad debt reserves		45,900,000	45,900,000
Provision for income taxes		0
Related amount of unrecognized deferred tax liability		10,500,000	17,100,000
Federal and state income taxes applicable to securities transactions		200,000	900,000	$ 300,000
Unrecognized tax benefits and interest		467,000	436,000	$ 326,000	$ 701,000
Unrecognized tax benefits that would affect the effective tax rate		500,000
Accrued interest related to uncertain tax positions		23,000	$ 22,000
Scenario, Forecast [Member]
Income Tax Disclosure [Line Items]
Federal statutory tax rate	21.00%
Your Community Bankshares, Inc [Member]
Income Tax Disclosure [Line Items]
Federal deferred tax assets net operating loss carryforwards		25,900,000
Indiana [Member]
Income Tax Disclosure [Line Items]
Deferred tax assets net operating loss carryforwards		$ 20,800,000
Earliest Tax Year [Member]
Income Tax Disclosure [Line Items]
Earliest year for tax examination		2,014
Earliest Tax Year [Member] | Your Community Bankshares, Inc [Member]
Income Tax Disclosure [Line Items]
Net operating loss carryforwards expiration date		2,030
Earliest Tax Year [Member] | Indiana [Member]
Income Tax Disclosure [Line Items]
Net operating loss carryforwards expiration date		2,031
Latest Tax Year [Member] | Your Community Bankshares, Inc [Member]
Income Tax Disclosure [Line Items]
Net operating loss carryforwards expiration date		2,036
Latest Tax Year [Member] | Indiana [Member]
Income Tax Disclosure [Line Items]
Net operating loss carryforwards expiration date		2,036

Income Taxes - Reconciliation f

Income Taxes - Reconciliation from Federal Statutory Income Tax Rate to Effective Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Federal statutory tax rate	35.00%	35.00%	35.00%
Tax reform remeasurement	8.60%	0.00%	0.00%
Net tax-exempt interest income on securities of state and political subdivisions	(6.00%)	(7.00%)	(6.80%)
State income taxes, net of federal tax effect	1.30%	1.40%	1.60%
Bank-owned life insurance	(1.10%)	(1.20%)	(1.60%)
General business credits	(1.70%)	(2.10%)	(2.10%)
All other-net	0.20%	0.30%	(0.10%)
Effective tax rate	36.30%	26.40%	26.00%

Income Taxes - Provision for In

Income Taxes - Provision for Income Taxes Applicable to Income Before Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current:
Federal									$ 24,634	$ 18,053	$ 15,661
State									2,061	2,159	2,089
Deferred:
Tax reform remeasurement									12,765
Federal									13,329	10,519	10,047
State									1,018	305	618
Total	$ 23,006	$ 10,527	$ 9,653	$ 10,622	$ 8,464	$ 5,793	$ 8,085	$ 8,694	$ 53,807	$ 31,036	$ 28,415

Income Taxes - Schedule of Inco

Income Taxes - Schedule of Income Tax Amounts were Recorded in Shareholder's Equity as Elements of Other Comprehensive Income (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Securities and defined benefit pension plan unrecognized items	$ 345	$ (3,480)	$ (1,202)

Income Taxes - Schedule of Defe

Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets:
Allowance for loan losses	$ 10,389	$ 16,198	$ 15,246
Compensation and benefits	2,536	5,444	6,114
Security gains and losses	821	2,854	2,964
Purchase accounting adjustments	1,565		1,275
Partnership adjustments			1,921
Non-accrual interest income	1,389	2,392	2,254
Tax credit carryforwards	5,204	12,744	13,580
Net operating loss carryforwards	6,062	12,020
Fair value adjustments on securities available-for-sale	3,962	5,394	1,979
Other	1,118	5,194	2,264
Gross deferred tax assets	33,046	62,240	47,597
Deferred tax liabilities:
Depreciation and amortization	(1,883)	(3,448)	(1,530)
Accretion on securities	(266)	(421)	(2)
Deferred fees and costs	(2,989)
Purchase accounting adjustments		(149)
Partnership adjustments	(674)	(1,128)
Other	(120)	(2,519)	(1,511)
Gross deferred tax liabilities	(5,932)	(7,665)	(3,043)
Net deferred tax assets	$ 27,114	$ 54,575	$ 44,554

Income Taxes - Schedule of Unre

Income Taxes - Schedule of Unrecognized Tax Benefits (Excluding Interest and Federal Income Tax Benefit of Unrecognized State Tax Benefits) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Balance at beginning of year	$ 436	$ 326	$ 701
Additions based on tax positions related to the current year	101	110	104
Reductions for tax positions of prior years			(100)
Reductions due to the statute of limitations	(70)		(379)
Settlements	0	0	0
Balance at end of year	$ 467	$ 436	$ 326

Fair Value Measurement - Schedu

Fair Value Measurement - Schedule of Fair Value of Assets and Liabilities Measured on Recurring and Nonrecurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities	$ 7,844	$ 7,071
Total securities - available-for-sale	1,267,478	1,241,176
Other real estate owned and repossessed assets	5,297	8,346
Loans held for sale	20,320	17,315
Other assets-interest rate derivatives agreements	7,351	5,596
Total assets recurring fair value measurements	1,302,993	1,253,843
Other liabilities - interest rate derivatives agreements	7,345	5,199
Total liabilities recurring fair value measurements	7,345	5,199
Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities	7,844	7,071
Total securities - available-for-sale	1,267,478	1,241,176
Nonrecurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	1,717	3,405
Other real estate owned and repossessed assets	5,297	8,346
Loans held for sale		17,315
Total nonrecurring fair value measurements	7,014	29,066
U.S. Government Sponsored Entities and Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	71,843	54,043
U.S. Government Sponsored Entities and Agencies [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	71,843	54,043
Residential Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Sponsored Entities and Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	934,922	938,289
Residential Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Sponsored Entities and Agencies [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	934,922	938,289
Commercial Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Sponsored Entities and Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	114,867	96,810
Commercial Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Sponsored Entities and Agencies [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	114,867	96,810
Obligations of State and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	104,830	111,663
Obligations of State and Political Subdivisions [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	104,830	111,663
Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	35,403	35,301
Corporate Debt Securities [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	35,403	35,301
Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	5,613	5,070
Equity Securities [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	5,613	5,070
Investments Measured at Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities	2,066	1,438
Total assets recurring fair value measurements	2,066	1,438
Investments Measured at Net Asset Value [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities	2,066	1,438
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities	5,778	5,633
Total securities - available-for-sale	5,613	2,938
Total assets recurring fair value measurements	11,391	8,571
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Trading securities	5,778	5,633
Total securities - available-for-sale	5,613	2,938
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Equity Securities [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	5,613	2,938
Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	1,261,865	1,238,238
Loans held for sale	20,320	17,315
Other assets-interest rate derivatives agreements	7,351	5,596
Total assets recurring fair value measurements	1,289,536	1,243,834
Other liabilities - interest rate derivatives agreements	7,345	5,199
Total liabilities recurring fair value measurements	7,345	5,199
Significant Other Observable Inputs (Level 2) [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	1,261,865	1,238,238
Significant Other Observable Inputs (Level 2) [Member] | Nonrecurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for sale		17,315
Total nonrecurring fair value measurements		17,315
Significant Other Observable Inputs (Level 2) [Member] | U.S. Government Sponsored Entities and Agencies [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	71,843	54,043
Significant Other Observable Inputs (Level 2) [Member] | Residential Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Sponsored Entities and Agencies [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	934,922	938,289
Significant Other Observable Inputs (Level 2) [Member] | Commercial Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Sponsored Entities and Agencies [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	114,867	96,810
Significant Other Observable Inputs (Level 2) [Member] | Obligations of State and Political Subdivisions [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	104,830	111,663
Significant Other Observable Inputs (Level 2) [Member] | Corporate Debt Securities [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	35,403	35,301
Significant Other Observable Inputs (Level 2) [Member] | Equity Securities [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale		2,132
Significant Unobservable Inputs (Level 3) [Member] | Nonrecurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	1,717	3,405
Other real estate owned and repossessed assets	5,297	8,346
Total nonrecurring fair value measurements	$ 7,014	$ 11,751

Fair Value Measurement - Additi

Fair Value Measurement - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair value transfer amount	$ 0	$ 0

Fair Value Measurement - Sch120

Fair Value Measurement - Schedule of Assets Measured at Fair Value on Nonrecurring Basis (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Other real estate owned and repossessed assets	$ 5,297	$ 8,346
Impaired loans, Appraisal adjustments	(4.80%)
Impaired loans, Liquidation expenses	(7.60%)
Nonrecurring Fair Value Measurements [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans	$ 1,717	3,405
Other real estate owned and repossessed assets	5,297	8,346
Significant Unobservable Inputs (Level 3) [Member] | Nonrecurring Fair Value Measurements [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans	1,717	3,405
Other real estate owned and repossessed assets	$ 5,297	$ 8,346
Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans, Appraisal adjustments		0.00%
Impaired loans, Liquidation expenses		1.50%
Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans, Appraisal adjustments		(70.00%)
Impaired loans, Liquidation expenses		8.00%
Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans, Appraisal adjustments	(4.80%)	(36.60%)
Impaired loans, Liquidation expenses	7.60%	4.60%

Fair Value Measurement - Sch121

Fair Value Measurement - Schedule of Assets Measured at Fair Value on Nonrecurring Basis (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans, Appraisal adjustments	(4.80%)
Impaired loans, Liquidation expenses	7.60%
Weighted Average [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans, Appraisal adjustments	(4.80%)	(36.60%)
Impaired loans, Liquidation expenses	(7.60%)	(4.60%)

Fair Value Measurement - Estima

Fair Value Measurement - Estimates Fair Value of Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financial Assets
Cash and due from banks	$ 117,572	$ 128,170	$ 86,685	$ 94,002
Trading securities	7,844	7,071
Securities available-for-sale	1,267,478	1,241,176
Securities held-to-maturity	1,009,500	1,067,967
Net loans	6,296,157	6,205,762
Loans held for sale	20,320	17,315
Other assets-interest rate derivatives	7,351	5,596
Accrued interest receivable	29,728	28,299
Financial Liabilities
Deposits	7,043,588	7,040,879
Federal Home Loan Bank borrowings	948,203	968,946
Other borrowings	184,805	199,376
Subordinated debt and junior subordinated debt	164,327	163,598
Other liabilities-interest rate derivatives	7,345	5,199
Accrued interest payable	3,178	2,204
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial Assets
Cash and due from banks	117,572	128,170
Trading securities	5,778	5,633
Securities available-for-sale	5,613	2,938
Accrued interest receivable	29,728	28,299
Financial Liabilities
Deposits	5,766,531	5,545,057
Other borrowings	182,785	197,164
Accrued interest payable	3,178	2,204
Significant Other Observable Inputs (Level 2) [Member]
Financial Assets
Securities available-for-sale	1,261,865	1,238,238
Securities held-to-maturity	1,023,191	1,076,189
Loans held for sale	20,320	17,315
Other assets-interest rate derivatives	7,351	5,596
Financial Liabilities
Deposits	1,287,005	1,507,444
Federal Home Loan Bank borrowings	944,706	974,430
Other borrowings	2,029	2,221
Subordinated debt and junior subordinated debt	146,484	134,859
Other liabilities-interest rate derivatives	7,345	5,199
Significant Unobservable Inputs (Level 3) [Member]
Financial Assets
Securities held-to-maturity	593	601
Net loans	6,212,823	6,073,558
Carrying Amount [Member]
Financial Assets
Cash and due from banks	117,572	128,170
Trading securities	7,844	7,071
Securities available-for-sale	1,267,478	1,241,176
Securities held-to-maturity	1,009,500	1,067,967
Net loans	6,296,157	6,205,762
Loans held for sale	20,320	17,315
Other assets-interest rate derivatives	7,351
Accrued interest receivable	29,728	28,299
Financial Liabilities
Deposits	7,043,588	7,040,879
Federal Home Loan Bank borrowings	948,203	968,946
Other borrowings	184,805	199,376
Subordinated debt and junior subordinated debt	164,327	163,598
Other liabilities-interest rate derivatives	7,345
Accrued interest payable	3,178	2,204
Fair Value Estimate [Member]
Financial Assets
Cash and due from banks	117,572	128,170
Trading securities	7,844	7,071
Securities available-for-sale	1,267,478	1,241,176
Securities held-to-maturity	1,023,784	1,076,790
Net loans	6,212,823	6,073,558
Loans held for sale	20,320	17,315
Other assets-interest rate derivatives	7,351
Accrued interest receivable	29,728	28,299
Financial Liabilities
Deposits	7,053,536	7,052,501
Federal Home Loan Bank borrowings	944,706	974,430
Other borrowings	184,814	199,385
Subordinated debt and junior subordinated debt	146,484	134,859
Other liabilities-interest rate derivatives	7,345
Accrued interest payable	3,178	2,204
Investments Measured at Net Asset Value [Member]
Financial Assets
Trading securities	$ 2,066	$ 1,438

Comprehensive Income_(Loss) - C

Comprehensive Income/(Loss) - Components of Accumulated Other Comprehensive Income/(Loss) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ 1,341,408	$ 1,122,132	$ 788,190
Amounts reclassified from accumulated other comprehensive income/(loss)	1,958	240	1,315
Total other comprehensive gain (loss)	1,212	(6,172)	(2,129)
Ending Balance	1,395,321	1,341,408	1,122,132
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(17,758)	(17,539)	(22,776)
Other comprehensive income/(loss) before reclassifications	239	(2,112)	3,233
Amounts reclassified from accumulated other comprehensive income/(loss)	2,194	1,893	2,004
Total other comprehensive gain (loss)	2,433	(219)	5,237
Adoption of accounting standard ASU 2018-02	(3,301)
Ending Balance	(18,626)	(17,758)	(17,539)
Accumulated Unrealized Gains (Losses) on Securities Available for Sale [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(9,890)	(4,162)	2,892
Other comprehensive income/(loss) before reclassifications	(985)	(4,300)	(6,677)
Amounts reclassified from accumulated other comprehensive income/(loss)	(27)	(1,428)	(377)
Total other comprehensive gain (loss)	(1,012)	(5,728)	(7,054)
Adoption of accounting standard ASU 2018-02	(2,348)
Ending Balance	(13,250)	(9,890)	(4,162)
Accumulated Unrealized Gains on Securities Transferred from Available For Sale to Held to Maturity [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	522	747	1,059
Amounts reclassified from accumulated other comprehensive income/(loss)	(209)	(225)	(312)
Total other comprehensive gain (loss)	(209)	(225)	(312)
Adoption of accounting standard ASU 2018-02	68
Ending Balance	381	522	747
Accumulated Other Comprehensive Loss [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(27,126)	(20,954)	(18,825)
Other comprehensive income/(loss) before reclassifications	(746)	(6,412)	(3,444)
Amounts reclassified from accumulated other comprehensive income/(loss)	1,958	240	1,315
Total other comprehensive gain (loss)	1,212	(6,172)	(2,129)
Adoption of accounting standard ASU 2018-02	(5,581)
Ending Balance	$ (31,495)	$ (27,126)	$ (20,954)

Comprehensive Income_(Loss) 124

Comprehensive Income/(Loss) - Components of Accumulated Other Comprehensive Income/(Loss) (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Percentage of Federal and State income tax rate	37.00%	37.00%	37.00%

Comprehensive Income_(Loss) - S

Comprehensive Income/(Loss) - Schedule of Amounts Reclassified from Accumulated Other Comprehensive Income/(Loss) (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net securities gains (Non-interest income)									$ (567)	$ (2,357)	$ (948)
Interest and dividends on securities (Interest and dividend income)									(58,120)	(56,880)	(56,078)
Employee benefits (Non-interest expense)									29,933	27,952	26,896
Provision for income taxes	$ 23,006	$ 10,527	$ 9,653	$ 10,622	$ 8,464	$ 5,793	$ 8,085	$ 8,694	53,807	31,036	28,415
Net effect on accumulated other comprehensive income for the period									1,958	240	1,315
Accumulated Unrealized Gains (Losses) on Securities Available for Sale [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net effect on accumulated other comprehensive income for the period									(27)	(1,428)	(377)
Accumulated Unrealized Gains on Securities Transferred from Available For Sale to Held to Maturity [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net effect on accumulated other comprehensive income for the period									(209)	(225)	(312)
Accumulated Defined Benefit Plans Adjustment [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net effect on accumulated other comprehensive income for the period									2,194	1,893	2,004
Amounts Reclassified From Accumulated Other Comprehensive Income/(Loss) [Member] | Accumulated Unrealized Gains (Losses) on Securities Available for Sale [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net securities gains (Non-interest income)									(42)	(2,251)	(596)
Provision for income taxes									15	823	219
Amounts Reclassified From Accumulated Other Comprehensive Income/(Loss) [Member] | Accumulated Unrealized Gains on Securities Transferred from Available For Sale to Held to Maturity [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest and dividends on securities (Interest and dividend income)									(326)	(357)	(494)
Provision for income taxes									117	132	182
Amounts Reclassified From Accumulated Other Comprehensive Income/(Loss) [Member] | Accumulated Defined Benefit Plans Adjustment [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Employee benefits (Non-interest expense)									3,247	3,046	3,205
Provision for income taxes									$ (1,053)	$ (1,153)	$ (1,201)

Commitments and Contingent L126

Commitments and Contingent Liabilities - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Allowance for credit losses associated with loan commitments	$ 574	$ 571	$ 613	$ 455
Liability associated with letters of credit	$ 200	$ 200

Commitments and Contingent L127

Commitments and Contingent Liabilities - Commitments to Extend Credit, Guarantees and Various Letters of Credit Outstanding (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Lines of credit	$ 1,452,697	$ 1,418,329
Loans approved but not closed	245,644	185,254
Overdraft limits	126,671	126,517
Letters of credit	31,951	32,907
Contingent obligations to purchase loans funded by other entities	$ 6,700	$ 13,036

Wesbanco Bank Community Deve128

Wesbanco Bank Community Development Corporation - Additional Information (Detail) - WBCDC [Member] - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule Of Subsidiary Financial Statements Table [Line Items]
New Markets Tax Credits	$ 60,000,000
Lower limit of poverty rate tracts	20.00%
Percentage income of median family	80.00%
Percentage of credit provided to the investor	39.00%
Period of credit allowance	7 years
Percentage of total amount investor receives as credit	5.00%
Percentage of total amount investor receives as credit for the remaining four years	6.00%
Amount received as tax credit	$ 22,400,000
Investment limit for credit allowance	60,000,000
Amount eligible to receive as tax credit	1,000,000
Provision for income tax	1,000,000	$ 1,800,000	$ 1,900,000
Tax credit carry forward	$ 0
Minimum percentage of QEI proceeds utilized	85.00%

Wesbanco Bank Community Deve129

Wesbanco Bank Community Development Corporation - Summary of New Market Tax Credit Carry Forward (Detail) $ in Thousands	Dec. 31, 2017USD ($)
Schedule Of Subsidiary Financial Statements Table [Line Items]
Aggregate QEI Amount	$ 11,000
New Markets Tax Credit for year 2018	660
New Markets Tax Credit for year 2019	300
2012 [Member]
Schedule Of Subsidiary Financial Statements Table [Line Items]
Aggregate QEI Amount	6,000
New Markets Tax Credit for year 2018	360
2013 [Member]
Schedule Of Subsidiary Financial Statements Table [Line Items]
Aggregate QEI Amount	5,000
New Markets Tax Credit for year 2018	300
New Markets Tax Credit for year 2019	$ 300

Wesbanco Bank Community Deve130

Wesbanco Bank Community Development Corporation - Summary of New Market Tax Credit Carry Forward (Parenthetical) (Detail) $ in Millions	Dec. 31, 2017USD ($)
WBCDC [Member]
Schedule Of Subsidiary Financial Statements Table [Line Items]
Qualified equity investment amount for which tax credit expired	$ 49

Wesbanco Bank Community Deve131

Wesbanco Bank Community Development Corporation - Schedule of Condensed Balance Sheet (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
ASSETS
Cash and due from banks	$ 117,572	$ 128,170	$ 86,685	$ 94,002
Loans, net of allowance for loan losses of $254	6,296,157	6,205,762
Other assets	155,004	180,488
Total Assets	9,816,178	9,790,877
Liabilities	8,420,857	8,449,469
Shareholder Equity	1,395,321	1,341,408	$ 1,122,132	$ 788,190
Total Liabilities and Shareholder Equity	9,816,178	9,790,877
WBCDC [Member]
ASSETS
Cash and due from banks	36,533	$ 31,303
Loans, net of allowance for loan losses of $254	35,218
Investments	820
Other assets	195
Total Assets	72,766
Liabilities	354
Shareholder Equity	72,412
Total Liabilities and Shareholder Equity	$ 72,766

Wesbanco Bank Community Deve132

Wesbanco Bank Community Development Corporation - Schedule of Condensed Balance Sheet (Parenthetical) (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Subsidiary Financial Statements Table [Line Items]
Allowance for loan losses	$ 45,284	$ 43,674	$ 41,710	$ 44,654
WBCDC [Member]
Schedule Of Subsidiary Financial Statements Table [Line Items]
Allowance for loan losses	$ 254

Wesbanco Bank Community Deve133

Wesbanco Bank Community Development Corporation - Schedule of Condensed Income Statement (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Interest income
Loans									$ 272,007	$ 226,993	$ 203,993
Total interest income	$ 84,851	$ 85,489	$ 82,160	$ 79,924	$ 80,819	$ 70,092	$ 67,585	$ 67,601	332,424	286,097	261,712
Provision for loan losses									9,983	8,520	8,195
Net interest income after provision for credit losses	70,806	71,738	69,756	68,008	69,560	59,812	57,963	57,518	280,309	244,852	228,634
Loss on investments	56	6	494	12	63	598	585	1,111	567	2,357
Non-interest expense	54,837	55,754	55,884	54,384	58,298	57,601	47,360	45,343	220,860	208,680	193,923
Income before provision for income taxes	38,903	36,883	35,994	36,508	32,682	23,228	30,194	31,568	148,289	117,671	109,177
Provision for income taxes	23,006	10,527	9,653	10,622	8,464	5,793	8,085	8,694	53,807	31,036	28,415
Net income	$ 15,897	$ 26,356	$ 26,341	$ 25,886	$ 24,218	$ 17,435	$ 22,109	$ 22,874	94,482	$ 86,635	$ 80,762
WBCDC [Member]
Interest income
Loans									1,282
Total interest income									1,282
Provision for loan losses									5
Net interest income after provision for credit losses									1,277
Loss on investments									(148)
Non-interest expense									235
Income before provision for income taxes									894
Provision for income taxes									354
Net income									$ 540

Wesbanco Bank Community Deve134

Wesbanco Bank Community Development Corporation - Schedule of Condensed Cash Flow Statement (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
OPERATING ACTIVITIES
Net income	$ 15,897	$ 26,356	$ 26,341	$ 25,886	$ 24,218	$ 17,435	$ 22,109	$ 22,874	$ 94,482	$ 86,635	$ 80,762
Provision for loan losses									9,983	8,520	8,195
Loss on investments	(56)	$ (6)	$ (494)	(12)	(63)	$ (598)	$ (585)	(1,111)	(567)	(2,357)
Decrease in other assets									4,593	13,137	(4,293)
Net change in other liabilities									2,944	7,404	(7,988)
Net cash provided by operating activities									141,626	123,077	88,386
INVESTING ACTIVITIES
Decrease in loans									(90,225)	(174,952)	(293,306)
Net cash provided by investing activities									(77,375)	194,588	(210,328)
FINANCING ACTIVITIES
Net cash provided by financing activities									(74,849)	(276,180)	114,625
Net increase in cash and cash equivalents									(10,598)	41,485	(7,317)
Cash and cash equivalents at beginning of the year				128,170				$ 86,685	128,170	86,685	94,002
Cash and cash equivalents at end of the year	117,572				128,170				117,572	128,170	$ 86,685
WBCDC [Member]
OPERATING ACTIVITIES
Net income									540
Provision for loan losses									5
Loss on investments									148
Decrease in other assets									91
Net change in other liabilities									80
Net cash provided by operating activities									864
INVESTING ACTIVITIES
Decrease in loans									4,366
Net cash provided by investing activities									4,366
FINANCING ACTIVITIES
Qualified equity investment by parent company									0
Net cash provided by financing activities									0
Net increase in cash and cash equivalents									5,230
Cash and cash equivalents at beginning of the year				$ 31,303					31,303
Cash and cash equivalents at end of the year	$ 36,533				$ 31,303				$ 36,533	$ 31,303

Transactions with Related Pa135

Transactions with Related Parties - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Related Party Transactions [Abstract]
Aggregate indebtedness of related parties	$ 16,700,000	$ 18,700,000	$ 9,600,000
Related party loans funded	4,300,000
Related party loans repaid	$ 6,300,000
Due date for related party loans	90 days
Delinquent related party loans outstanding	$ 0	$ 0	$ 0

Regulatory Matters - Additional

Regulatory Matters - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Potential maximum dividends without prior regulatory approval	$ 58,700,000
Average required reserve balance in Federal Reserve Bank	$ 0	$ 2,000,000
Percentage of Risk-weighted assets in bank holding companies in total capital	8.00%
Common equity tier 1, minimum value	4.50%
Common equity tier 1, well capitalized	6.50%
Percentage of Risk-weighted assets in banking subsidiaries	6.00%
Percentage of well-capitalized levels of Tier 1 risk-based capital	8.00%
Percentage of well-capitalized levels of total risk-based capital	10.00%
Percentage of well-capitalized levels of Tier 1 leverage capital	5.00%
Junior subordinated debt	$ 138,564,000
Provision of the Dodd-Frank	$ 15,000,000,000
Minimum [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Minimum Tier 1 leverage ratio	4.00%
WesBanco Bank Inc [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Percentage of Risk-weighted assets in bank holding companies in total capital	8.00%
Common equity tier 1, minimum value	4.50%
Common equity tier 1, well capitalized	6.50%
Percentage of Risk-weighted assets in banking subsidiaries	6.00%
Percentage of well-capitalized levels of Tier 1 risk-based capital	8.00%
Percentage of well-capitalized levels of total risk-based capital	10.00%
Percentage of well-capitalized levels of Tier 1 leverage capital	5.00%
Junior Subordinated Debt [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Junior subordinated debt	$ 138,600,000

Regulatory Matters - Summary of

Regulatory Matters - Summary of Risk-Based Capital Amounts and Ratios (Detail) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Percentage of risk-weighted assets in bank holding companies in Tier 1	4.00%
Common equity tier 1, minimum value	4.50%
Tier 1 capital to risk-weighted assets, minimum value	6.00%
Total capital to risk-weighted assets, minimum value	8.00%
Tier 1 leverage, well capitalized	5.00%
Common equity tier 1, well capitalized	6.50%
Tier 1 capital to risk-weighted assets, well capitalized	8.00%
Total capital to risk-weighted assets, well capitalized	10.00%
Tier 1 leverage, amount	$ 970,425,000	$ 901,873,000
Common equity tier 1, amount	834,554,000	773,306,000
Tier 1 capital to risk-weighted assets, amount	970,425,000	901,873,000
Total capital to risk-weighted assets, amount	$ 1,042,124,000	$ 971,762,000
Tier 1 leverage, ratio	10.39%	9.81%
Common equity tier 1, ratio	12.14%	11.28%
Tier 1 capital to risk-weighted assets, ratio	14.12%	13.16%
Total capital to risk-weighted assets, ratio	15.16%	14.18%
WesBanco Bank Inc [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Percentage of risk-weighted assets in bank holding companies in Tier 1	4.00%
Common equity tier 1, minimum value	4.50%
Tier 1 capital to risk-weighted assets, minimum value	6.00%
Total capital to risk-weighted assets, minimum value	8.00%
Tier 1 leverage, well capitalized	5.00%
Common equity tier 1, well capitalized	6.50%
Tier 1 capital to risk-weighted assets, well capitalized	8.00%
Total capital to risk-weighted assets, well capitalized	10.00%
Tier 1 leverage, amount	$ 869,227,000	$ 827,173,000
Common equity tier 1, amount	869,227,000	827,173,000
Tier 1 capital to risk-weighted assets, amount	869,227,000	827,173,000
Total capital to risk-weighted assets, amount	$ 940,303,000	$ 896,598,000
Tier 1 leverage, ratio	9.32%	9.02%
Common equity tier 1, ratio	12.66%	12.10%
Tier 1 capital to risk-weighted assets, ratio	12.66%	12.10%
Total capital to risk-weighted assets, ratio	13.70%	13.11%
Minimum [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 leverage, amount	$ 373,566,000	$ 367,843,000
Common equity tier 1, amount	309,298,000	308,462,000
Tier 1 capital to risk-weighted assets, amount	412,397,000	411,283,000
Total capital to risk-weighted assets, amount	549,863,000	548,378,000
Minimum [Member] | WesBanco Bank Inc [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 leverage, amount	372,900,000	366,903,000
Common equity tier 1, amount	308,900,000	307,728,000
Tier 1 capital to risk-weighted assets, amount	411,866,000	410,305,000
Total capital to risk-weighted assets, amount	$ 549,155,000	$ 547,073,000

Condensed Parent Company Fin138

Condensed Parent Company Financial Statements - Schedule of Condensed Balance Sheet (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
ASSETS
Cash and short-term investments	$ 117,572	$ 128,170	$ 86,685	$ 94,002
Securities available-for-sale, at fair value	1,267,478	1,241,176
Other assets	155,004	180,488
Total Assets	9,816,178	9,790,877
LIABILITIES
Junior subordinated debt owed to unconsolidated subsidiary trusts	138,564
Total Liabilities	8,420,857	8,449,469
SHAREHOLDERS' EQUITY	1,395,321	1,341,408	1,122,132	788,190
Total Liabilities and Shareholders' Equity	9,816,178	9,790,877
Parent Company [Member]
ASSETS
Cash and short-term investments	75,911	47,035	$ 33,172	$ 61,732
Investment in subsidiaries-Bank	1,431,021	1,404,565
Investment in subsidiaries-Nonbank	7,755	8,228
Securities available-for-sale, at fair value	2,687	2,133
Other assets	28,614	28,602
Total Assets	1,545,988	1,490,563
LIABILITIES
Junior subordinated debt owed to unconsolidated subsidiary trusts	138,564	137,559
Dividends payable and other liabilities	12,103	11,596
Total Liabilities	150,667	149,155
SHAREHOLDERS' EQUITY	1,395,321	1,341,408
Total Liabilities and Shareholders' Equity	$ 1,545,988	$ 1,490,563

Condensed Parent Company Fin139

Condensed Parent Company Financial Statements - Schedule of Condensed Income Statement (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Condensed Income Statements, Captions [Line Items]
Income from securities	$ 84,851	$ 85,489	$ 82,160	$ 79,924	$ 80,819	$ 70,092	$ 67,585	$ 67,601	$ 332,424	$ 286,097	$ 261,712
Other income									8,641	9,751	5,532
Interest expense	11,669	11,235	10,021	9,205	9,131	8,066	7,811	7,759	42,129	32,767	24,725
Other expense									45,330	41,000	38,887
Total non-interest expense	54,837	55,754	55,884	54,384	58,298	57,601	47,360	45,343	220,860	208,680	193,923
Income tax benefit	23,006	10,527	9,653	10,622	8,464	5,793	8,085	8,694	53,807	31,036	28,415
NET INCOME	$ 15,897	$ 26,356	$ 26,341	$ 25,886	$ 24,218	$ 17,435	$ 22,109	$ 22,874	94,482	86,635	80,762
Parent Company [Member]
Condensed Income Statements, Captions [Line Items]
Dividends from subsidiaries-Bank									72,000	85,000	60,000
Dividends from subsidiaries-Nonbank									2,520	800	500
Income from securities									73	75	75
Other income									203	147	104
Total income									74,796	86,022	60,679
Interest expense									6,032	4,136	3,315
Other expense									4,004	5,628	5,547
Total non-interest expense									10,036	9,764	8,862
Income before income tax benefit and undistributed net income of subsidiaries									64,760	76,258	51,817
Income tax benefit									(4,726)	(3,149)	(2,971)
Income before undistributed net income of subsidiaries									69,486	79,407	54,788
Equity in undistributed net income of subsidiaries									24,996	7,228	25,974
NET INCOME									$ 94,482	$ 86,635	$ 80,762

Condensed Parent Company Fin140

Condensed Parent Company Financial Statements - Schedule of Condensed Cash Flow Statement (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
OPERATING ACTIVITIES
Net income	$ 15,897	$ 26,356	$ 26,341	$ 25,886	$ 24,218	$ 17,435	$ 22,109	$ 22,874	$ 94,482	$ 86,635	$ 80,762
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed net income										(900)	(600)
Decrease in other assets									4,593	13,137	(4,293)
Other-net									(438)	(574)	248
Net cash provided by operating activities									141,626	123,077	88,386
INVESTING ACTIVITIES
Proceed from sales - securities available-for-sale									7,760	277,225	635,609
Purchase of securities - securities available-for-sale									(252,314)	(213,894)	(526,502)
Acquisitions and additional capitalization of subsidiaries, net of cash (paid) acquired										4,863	(28,551)
Net cash (used in) provided by investing activities									(77,375)	194,588	(210,328)
FINANCING ACTIVITIES
Repayment of junior subordinated debt											(36,083)
Issuance of common stock									1,040	1,713
Repurchase of common stock warrant											(2,247)
Treasury shares (purchased) sold-net										(3,026)	(2,542)
Net cash (used in) provided by financing activities									(74,849)	(276,180)	114,625
Net increase (decrease) in cash and cash equivalents									(10,598)	41,485	(7,317)
Cash and cash equivalents at beginning of the year				128,170				86,685	128,170	86,685	94,002
Cash and cash equivalents at end of the year	117,572				128,170				117,572	128,170	86,685
Parent Company [Member]
OPERATING ACTIVITIES
Net income									94,482	86,635	80,762
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed net income									(24,996)	(7,228)	(25,974)
Decrease in other assets									566	14,679	199
Other-net									2,848	2,094	1,657
Net cash provided by operating activities									72,900	96,180	56,644
INVESTING ACTIVITIES
Proceed from sales - securities available-for-sale											210
Purchase of securities - securities available-for-sale									(200)
Acquisitions and additional capitalization of subsidiaries, net of cash (paid) acquired										(43,199)	1,465
Net cash (used in) provided by investing activities									(200)	(43,199)	1,675
FINANCING ACTIVITIES
Repayment of junior subordinated debt											(36,083)
Repayment of other borrowings											(13,000)
Issuance of common stock									1,040	1,713
Repurchase of common stock warrant											(2,247)
Treasury shares (purchased) sold-net										(3,026)	(2,542)
Dividends paid to common and preferred shareholders									(44,864)	(37,805)	(33,007)
Net cash (used in) provided by financing activities									(43,824)	(39,118)	(86,879)
Net increase (decrease) in cash and cash equivalents									28,876	13,863	(28,560)
Cash and cash equivalents at beginning of the year				$ 47,035				$ 33,172	47,035	33,172	61,732
Cash and cash equivalents at end of the year	$ 75,911				$ 47,035				$ 75,911	$ 47,035	$ 33,172

Business Segments - Additional

Business Segments - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)Segment	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Segment Reporting Information [Line Items]
Operating segments | Segment	2
Trust and Investment Services [Member]
Segment Reporting Information [Line Items]
Market value of assets managed or held in custody by trust and investment services segment	$ 3,900	$ 3,700	$ 3,600
Total non-fiduciary assets of the trust and investment services segment	$ 1.5	$ 4.3	$ 3.3

Business Segments - Financial I

Business Segments - Financial Information by Business Segment (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Interest and dividend income	$ 84,851	$ 85,489	$ 82,160	$ 79,924	$ 80,819	$ 70,092	$ 67,585	$ 67,601	$ 332,424	$ 286,097	$ 261,712
Interest expense	11,669	11,235	10,021	9,205	9,131	8,066	7,811	7,759	42,129	32,767	24,725
Net interest income	73,182	74,254	72,139	70,719	71,688	62,026	59,774	59,842	290,295	253,330	236,987
Provision for credit losses	2,376	2,516	2,383	2,711	2,128	2,214	1,811	2,324	9,986	8,478	8,353
Net interest income after provision for credit losses	70,806	71,738	69,756	68,008	69,560	59,812	57,963	57,518	280,309	244,852	228,634
Non-interest income									88,840	81,499	74,466
Non-interest expense	54,837	55,754	55,884	54,384	58,298	57,601	47,360	45,343	220,860	208,680	193,923
Income before provision for income taxes	38,903	36,883	35,994	36,508	32,682	23,228	30,194	31,568	148,289	117,671	109,177
Provision for income taxes	23,006	10,527	9,653	10,622	8,464	5,793	8,085	8,694	53,807	31,036	28,415
Net income	$ 15,897	$ 26,356	$ 26,341	$ 25,886	$ 24,218	$ 17,435	$ 22,109	$ 22,874	94,482	86,635	80,762
Community Banking [Member]
Segment Reporting Information [Line Items]
Interest and dividend income									332,424	286,097	261,712
Interest expense									42,129	32,767	24,725
Net interest income									290,295	253,330	236,987
Provision for credit losses									9,986	8,478	8,353
Net interest income after provision for credit losses									280,309	244,852	228,634
Non-interest income									66,100	59,869	52,566
Non-interest expense									207,441	196,784	181,821
Income before provision for income taxes									138,968	107,937	99,379
Provision for income taxes									50,079	27,142	24,496
Net income									88,889	80,795	74,883
Trust and Investment Services [Member]
Segment Reporting Information [Line Items]
Non-interest income									22,740	21,630	21,900
Non-interest expense									13,419	11,896	12,102
Income before provision for income taxes									9,321	9,734	9,798
Provision for income taxes									3,728	3,894	3,919
Net income									$ 5,593	$ 5,840	$ 5,879

Condensed Quarterly Statemen143

Condensed Quarterly Statements of Income (Unaudited) - Consolidated Selected Quarterly Statements of Income (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Interest and dividend income	$ 84,851	$ 85,489	$ 82,160	$ 79,924	$ 80,819	$ 70,092	$ 67,585	$ 67,601	$ 332,424	$ 286,097	$ 261,712
Interest expense	11,669	11,235	10,021	9,205	9,131	8,066	7,811	7,759	42,129	32,767	24,725
Net interest income	73,182	74,254	72,139	70,719	71,688	62,026	59,774	59,842	290,295	253,330	236,987
Provision for credit losses	2,376	2,516	2,383	2,711	2,128	2,214	1,811	2,324	9,986	8,478	8,353
Net interest income after provision for credit losses	70,806	71,738	69,756	68,008	69,560	59,812	57,963	57,518	280,309	244,852	228,634
Non-interest income	22,878	20,893	21,628	22,872	21,357	20,419	19,006	18,282	88,273	79,142
Net securities gains	56	6	494	12	63	598	585	1,111	567	2,357
Non-interest expense	54,837	55,754	55,884	54,384	58,298	57,601	47,360	45,343	220,860	208,680	193,923
Income before provision for income taxes	38,903	36,883	35,994	36,508	32,682	23,228	30,194	31,568	148,289	117,671	109,177
Provision for income taxes	23,006	10,527	9,653	10,622	8,464	5,793	8,085	8,694	53,807	31,036	28,415
Net income	$ 15,897	$ 26,356	$ 26,341	$ 25,886	$ 24,218	$ 17,435	$ 22,109	$ 22,874	$ 94,482	$ 86,635	$ 80,762
Earnings per common share-basic	$ 0.36	$ 0.60	$ 0.60	$ 0.59	$ 0.55	$ 0.44	$ 0.58	$ 0.60	$ 2.15	$ 2.16	$ 2.15
Earnings per common share-diluted	$ 0.36	$ 0.60	$ 0.60	$ 0.59	$ 0.55	$ 0.44	$ 0.58	$ 0.60	$ 2.14	$ 2.16	$ 2.15