WesBanco (WSBC) 10-Q 25 Oct 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2013	Oct. 21, 2013
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	30-Sep-13
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q3
Entity Registrant Name	WESBANCO INC
Entity Central Index Key	203596
Current Fiscal Year End Date	-19
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		29,350,061

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
ASSETS
Cash and due from banks, including interest bearing amounts of $5,405 and $33,889, respectively	$145,639	$125,605
Securities:
Available-for-sale, at fair value	933,455	1,021,244
Held-to-maturity (fair values of $607,215 and $639,273, respectively)	602,588	602,509
Total securities	1,536,043	1,623,753
Loans held for sale	6,601	21,903
Portfolio loans, net of unearned income	3,836,538	3,687,762
Allowance for loan losses	-47,342	-52,699
Net portfolio loans	3,789,196	3,635,063
Premises and equipment, net	92,696	88,866
Accrued interest receivable	19,903	19,354
Goodwill and other intangible assets, net	321,972	324,465
Bank-owned life insurance	120,457	119,671
Other assets	105,853	120,037
Total Assets	6,138,360	6,078,717
Deposits:
Non-interest bearing demand	917,478	874,923
Interest bearing demand	870,319	831,368
Money market	858,422	847,805
Savings deposits	775,776	740,568
Certificates of deposit	1,638,447	1,649,620
Total deposits	5,060,442	4,944,284
Federal Home Loan Bank borrowings	59,918	111,187
Other short-term borrowings	124,179	142,971
Junior subordinated debt owed to unconsolidated subsidiary trusts	106,127	113,832
Total borrowings	290,224	367,990
Accrued interest payable	3,535	3,856
Other liabilities	47,471	48,403
Total Liabilities	5,401,672	5,364,533
SHAREHOLDERS' EQUITY
Preferred stock, no par value; 1,000,000 shares authorized; none outstanding
Common stock, $2.0833 par value; 50,000,000 shares authorized; 29,350,061 and 29,214,660 shares issued and outstanding in 2013 and 2012, respectively	61,144	60,863
Capital surplus	244,352	241,672
Retained earnings	450,833	419,246
Accumulated other comprehensive loss	-18,442	-6,365
Deferred benefits for directors	-1,199	-1,232
Total Shareholders' Equity	736,688	714,184
Total Liabilities and Shareholders' Equity	$6,138,360	$6,078,717

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, except Share data, unless otherwise specified
Statement Of Financial Position [Abstract]
Interest bearing deposits, banks	$5,405	$33,889
Held-to-maturity securities, fair values	$607,215	$639,273
Preferred stock, par value	$0	$0
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares outstanding	0	0
Common stock, par value	$2.08	$2.08
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	29,350,061	29,214,660
Common stock, shares outstanding	29,350,061	29,214,660

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
INTEREST AND DIVIDEND INCOME
Loans, including fees	$43,678	$41,423	$131,706	$124,345
Interest and dividends on securities:
Taxable	7,226	7,722	22,015	24,784
Tax-exempt	3,355	3,113	9,748	9,270
Total interest and dividends on securities	10,581	10,835	31,763	34,054
Other interest income	58	30	165	115
Total interest and dividend income	54,317	52,288	163,634	158,514
INTEREST EXPENSE
Interest bearing demand deposits	369	397	1,035	1,132
Money market deposits	345	487	1,023	1,786
Savings deposits	128	202	395	697
Certificates of deposit	5,597	6,450	17,626	20,050
Total interest expense on deposits	6,439	7,536	20,079	23,665
Federal Home Loan Bank borrowings	291	1,020	900	3,684
Other short-term borrowings	651	1,169	1,900	3,503
Junior subordinated debt owed to unconsolidated subsidiary trusts	805	869	2,506	2,598
Total interest expense	8,186	10,594	25,385	33,450
NET INTEREST INCOME	46,131	41,694	138,249	125,064
Provision for credit losses	2,819	4,497	5,942	16,602
Net interest income after provision for credit losses	43,312	37,197	132,307	108,462
NON-INTEREST INCOME
Trust fees	4,854	4,379	14,694	13,390
Service charges on deposits	4,650	4,362	13,309	12,574
Electronic banking fees	3,124	2,846	9,186	8,529
Net securities brokerage revenue	1,506	1,131	4,644	3,319
Bank-owned life insurance	911	891	3,739	2,646
Net gains on sales of mortgage loans	745	993	2,157	1,860
Net securities (losses) / gains	-15	316	687	1,711
Net gain / (loss) on other real estate owned and other assets	8	-48	63	-298
Other income	1,333	1,092	3,857	3,447
Total non-interest income	17,116	15,962	52,336	47,178
NON-INTEREST EXPENSE
Salaries and wages	16,480	14,758	48,079	43,028
Employee benefits	5,323	5,000	17,481	15,538
Net occupancy	2,921	2,654	8,943	8,133
Equipment	2,692	2,300	7,901	6,617
Marketing	1,585	795	4,015	3,282
FDIC insurance	916	951	2,806	2,962
Amortization of intangible assets	556	519	1,742	1,580
Restructuring and merger-related expense	36	1,518	1,265	1,518
Other operating expenses	9,500	8,295	28,024	25,880
Total non-interest expense	40,009	36,790	120,256	108,538
Income before provision for income taxes	20,419	16,369	64,387	47,102
Provision for income taxes	4,884	3,463	15,815	10,208
NET INCOME	15,535	12,906	48,572	36,894
EARNINGS PER COMMON SHARE
Basic	$0.53	$0.48	$1.66	$1.38
Diluted	$0.53	$0.48	$1.66	$1.38
AVERAGE COMMON SHARES OUTSTANDING
Basic	29,325,128	26,664,882	29,260,967	26,646,719
Diluted	29,412,458	26,672,849	29,328,305	26,651,322
DIVIDENDS DECLARED PER COMMON SHARE	$0.20	$0.18	$0.58	$0.52
COMPREHENSIVE INCOME	$14,422	$14,768	$36,495	$38,815

Consolidated_Statements_of_Cha

Consolidated Statements of Changes in Shareholders' Equity (USD $)	Total	Common Stock [Member]	Capital Surplus [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income / (Loss) [Member]	Deferred Benefits for Directors [Member]
In Thousands, except Share data
Beginning Balance at Dec. 31, 2011	$633,790	$55,487	$191,679	$388,818	($96)	($902)	($1,196)
Beginning Balance, shares at Dec. 31, 2011		26,629,360
Net income	36,894			36,894
Other comprehensive income / (loss)	1,921					1,921
Comprehensive income	38,815
Common dividends declared ($0.58 and $0.52 per share in September 30, 2013 and September 30, 2012 respectively)	-13,859			-13,859
Stock options exercised	17				17
Stock options exercised, shares		875
Restricted stock granted		71	-198		127
Restricted stock granted, shares		40,050
Treasury shares acquired	-70		22		-92
Treasury shares acquired, shares		-4,766
Stock compensation expense	629		629
Deferred benefits for directors - net			27				-27
Ending Balance at Sep. 30, 2012	659,322	55,558	192,159	411,853	-44	1,019	-1,223
Ending Balance, shares at Sep. 30, 2012		26,665,519
Beginning Balance at Dec. 31, 2012	714,184	60,863	241,672	419,246		-6,365	-1,232
Beginning Balance, shares at Dec. 31, 2012		29,214,660
Net income	48,572			48,572
Other comprehensive income / (loss)	-12,077					-12,077
Comprehensive income	36,495
Common dividends declared ($0.58 and $0.52 per share in September 30, 2013 and September 30, 2012 respectively)	-16,985			-16,985
Stock options exercised	2,671	233	2,411		27
Stock options exercised, shares		113,674
Restricted stock granted		57	-326		269
Restricted stock granted, shares		38,250
Treasury shares acquired	-296				-296
Treasury shares acquired, shares		-11,851
Adjustment to shares issued in acquisition	-104	-9	-95
Adjustment to shares issued in acquisition, shares		-4,672
Stock compensation expense	723		723
Deferred benefits for directors - net			-33				33
Ending Balance at Sep. 30, 2013	$736,688	$61,144	$244,352	$450,833		($18,442)	($1,199)
Ending Balance, shares at Sep. 30, 2013		29,350,061

Consolidated_Statements_of_Cha1

Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) (USD $)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Common dividends declared, per share	$0.58	$0.52
Retained Earnings [Member]
Common dividends declared, per share	$0.58	$0.52

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Statement Of Cash Flows [Abstract]
NET CASH PROVIDED BY OPERATING ACTIVITIES	$91,567	$64,009
INVESTING ACTIVITIES:
Net increase in loans	-159,087	-142,536
Securities available-for-sale:
Proceeds from sales	9,265	48,068
Proceeds from maturities, prepayments and calls	192,714	335,918
Purchases of securities	-137,156	-360,600
Securities held-to-maturity:
Proceeds from maturities, prepayments and calls	74,590	83,552
Purchases of securities	-77,179	-52,626
Purchases of premises and equipment - net	-6,571	-2,504
Sale of portfolio loans - net	5,886	7,883
Net cash used in investing activities	-97,538	-82,845
FINANCING ACTIVITIES:
Increase in deposits	117,049	94,339
Repayment of Federal Home Loan Bank borrowings	-50,627	-76,400
Decrease in other short-term borrowings	-18,421	-9,644
Repayment of junior subordinated debt	-7,732
Dividends paid to common shareholders	-16,373	-13,320
Treasury shares purchased - net	-274	-53
Issuance of common stock	2,383
Net cash provided by (used in) financing activities	26,005	-5,078
Net increase (decrease) in cash and cash equivalents	20,034	-23,914
Cash and cash equivalents at beginning of the period	125,605	140,325
Cash and cash equivalents at end of the period	145,639	116,411
SUPPLEMENTAL DISCLOSURES:
Interest paid on deposits and other borrowings	25,802	33,797
Income taxes paid	15,725	8,370
Transfers of loans to other real estate owned	1,800	3,452
Transfers of loans to held for sale	$9,434	$10,163

Summary_of_Significant_Account

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	NOTE 1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
	Basis of presentation — The accompanying unaudited interim financial statements of WesBanco, Inc. and its consolidated subsidiaries (“WesBanco”) have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with our Annual Report on Form 10-K for the year ended December 31, 2012.
	WesBanco’s interim financial statements have been prepared following the significant accounting policies disclosed in Note 1 of the Notes to the Consolidated Financial Statements of its 2012 Annual Report on Form 10-K filed with the Securities and Exchange Commission. In the opinion of management, the accompanying interim financial information reflects all adjustments, including normal recurring adjustments, necessary to present fairly WesBanco’s financial position and results of operations for each of the interim periods presented. Results of operations for interim periods are not necessarily indicative of the results of operations that may be expected for a full year.
	Recent accounting pronouncements — In July 2013, the Financial Accounting Standards Board (the “FASB”) issued an accounting pronouncement to improve the reporting for unrecognized tax benefits when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists. The pronouncement is expected to reduce diversity in practice by providing guidance on the presentation of unrecognized tax benefits and will better reflect the manner in which an entity would settle at the reporting date any additional income taxes that would result from the disallowance of a tax position when net operating loss carryforwards, similar tax losses, or tax credit carryforwards exist. The pronouncement is effective prospectively for fiscal years, and interim periods within those years, beginning after December 15, 2013. The adoption of this pronouncement is not expected to have a material impact on WesBanco’s consolidated financial statements.
	In February 2013, the FASB issued an accounting pronouncement to improve the reporting of reclassifications out of accumulated other comprehensive income. The amendment does not change the current requirements for reporting net income or other comprehensive income in the financial statements. However, the amendment requires an entity to provide information about the amounts reclassified out of accumulated other comprehensive income by component and to include references to other disclosures. The pronouncement is effective prospectively for interim and annual reporting periods beginning after December 15, 2012. The adoption of this pronouncement did not have a material impact on WesBanco’s consolidated financial statements.
	In December 2011, the FASB issued an accounting pronouncement which requires entities to disclose both gross and net information about instruments and transactions eligible for offset in the statement of financial position, including instruments and transactions subject to master netting arrangements. The scope would include derivatives, sale and repurchase agreements and reverse sale and repurchase agreements, and securities borrowing and securities lending arrangements. The objective of this pronouncement is to enhance disclosures required by GAAP by requiring improved information about financial instruments and derivative instruments that are either offset in accordance with existing GAAP or subject to an enforceable master netting arrangement or similar agreement. This information will enable users of an entity’s financial statements to evaluate the effect or potential effect of netting arrangements on an entity’s financial position, including the effect or potential effect of rights of setoff associated with certain financial instruments and derivative instruments. In January 2013, the FASB issued an accounting pronouncement to clarify and limit the scope of the aforementioned pronouncement by more specifically defining transactions eligible for offset. The pronouncements should be applied retrospectively effective for fiscal years, and interim periods within those years, beginning on or after January 1, 2013. The adoption of these pronouncements did not have a material impact on WesBanco’s consolidated financial statements.

Earnings_Per_Common_Share

Earnings Per Common Share	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]
Earnings Per Common Share	NOTE 2. EARNINGS PER COMMON SHARE
	Earnings per common share are calculated as follows:
		For the Three Months Ended				For the Nine Months Ended
		September 30,				September 30,
	(unaudited, in thousands, except shares and per share amounts)	2013		2012		2013		2012
	Numerator for both basic and diluted earnings per common share:
	Net income	$	15,535	$	12,906	$	48,572	$	36,894
	Denominator:
	Total average basic common shares outstanding		29,325,128		26,664,882		29,260,967		26,646,719
	Effect of dilutive stock options		87,330		7,967		67,338		4,603
	Total diluted average common shares outstanding		29,412,458		26,672,849		29,328,305		26,651,322
	Earnings per common share - basic	$	0.53	$	0.48	$	1.66	$	1.38
	Earnings per common share - diluted	$	0.53	$	0.48	$	1.66	$	1.38

Securities

Securities	9 Months Ended
	Sep. 30, 2013
Investments Debt And Equity Securities [Abstract]
Securities	NOTE 3. SECURITIES
	The following table presents the fair value and amortized cost of available-for-sale and held-to-maturity securities:
			September 30, 2013										December 31, 2012
	(unaudited, in thousands)		Amortized		Gross			Gross			Estimated		Amortized			Gross		Gross			Estimated
			Cost		Unrealized			Unrealized			Fair Value		Cost			Unrealized		Unrealized			Fair Value
					Gains			Losses								Gains		Losses
	Available-for-sale
	Obligations of government agencies		$	71,893	$	20		$	(1,256	)	$	70,657	$	96,257		$	411	$	(56	)	$	96,612
	Residential mortgage-backed securities and collateralized mortgage obligations of government agencies			686,216		4,226			(9,431	)		681,011		721,824			10,690		(304	)		732,210
	Obligations of state and political subdivisions			123,423		5,069			(260	)		128,232		139,511			9,133		(9	)		148,635
	Corporate debt securities			41,819		135			(372	)		41,582		32,706			213		(234	)		32,685
	Total debt securities		$	923,351	$	9,450		$	(11,319	)	$	921,482	$	990,298		$	20,447	$	(603	)	$	1,010,142
	Equity securities			10,244		1,729			—			11,973		10,207			916		(21	)		11,102
	Total available-for-sale securities		$	933,595	$	11,179		$	(11,319	)	$	933,455	$	1,000,505		$	21,363	$	(624	)	$	1,021,244
	Held-to-maturity
	Residential mortgage-backed securities and collateralized mortgage obligations of government agencies		$	105,907	$	3,521		$	(744	)	$	108,684	$	152,872		$	6,421	$	(80	)	$	159,213
	Other residential collateralized mortgage obligations			—		—			—			—		353			8		—			361
	Obligations of state and political subdivisions			493,968		13,872			(11,854	)		495,986		449,284			31,244		(829	)		479,699
	Corporate debt securities			2,713		—			(168	)		2,545		—			—		—			—
	Total held-to-maturity securities		$	602,588	$	17,393		$	(12,766	)	$	607,215	$	602,509		$	37,673	$	(909	)	$	639,273
	Total securities		$	1,536,183	$	28,572		$	(24,085	)	$	1,540,670	$	1,603,014		$	59,036	$	(1,533	)	$	1,660,517
	At September 30, 2013, and December 31, 2012, there were no holdings of any one issuer, other than the U.S. government 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 September 30, 2013. In some instances, the issuers may have the right to call or prepay obligations without penalty prior to the contractual maturity date.
			September 30, 2013
	(unaudited, in thousands)		One Year		One to			Five to			After		Mortgage-backed			Total
			or less		Five Years			Ten Years			Ten Years		and Equity
	Available-for-sale
	Obligations of government agencies		$	—	$	17,776		$	39,269		$	13,612	$	—		$	70,657
	Residential mortgage-backed securities and collateralized mortgage obligations of government agencies (1)			—		—			—			—		681,011			681,011
	Obligations of states and political subdivisions			8,388		45,121			26,389			48,334		—			128,232
	Corporate debt securities			5,075		16,198			15,553			4,756		—			41,582
	Equity securities (2)			—		—			—			—		11,973			11,973
	Total available-for-sale securities		$	13,463	$	79,095		$	81,211		$	66,702	$	692,984		$	933,455
	Held-to-maturity (3)
	Residential mortgage-backed securities and collateralized mortgage obligations of		$	—	$	—		$	—		$	—	$	108,684		$	108,684
	obligations (1)
	Obligations of states and political subdivisions			3,860		9,407			125,581			357,138		—			495,986
	Corporate debt securities			—		—			2,545			—		—			2,545
	Total held-to-maturity securities		$	3,860	$	9,407		$	128,126		$	357,138	$	108,684		$	607,215
	Total securities		$	17,323	$	88,502		$	209,337		$	423,840	$	801,668		$	1,540,670
	-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 $602.6 million.
	Securities with aggregate par values of $703.2 million and $710.5 million at September 30, 2013 and December 31, 2012, 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 $9.3 million and $48.1 million for the nine months ended September 30, 2013 and 2012, respectively. Net unrealized (losses) gains on available-for-sale securities included in accumulated other comprehensive income, net of tax, as of September 30, 2013 and December 31, 2012 were ($0.1) million and $13.0 million, respectively. Gross security gains of $0.3 million and $1.4 million on available-for-sale securities were realized for the nine months ended September 30, 2013 and 2012, respectively, while gross security losses of $0.2 million were realized for the nine months ended September 30, 2013 primarily due to the write-down of two equity securities. Additionally, gross security gains of $0.6 million and $0.3 million on held-to-maturity securities were realized for the nine months ended September 30, 2013 and 2012, respectively.
	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 September 30, 2013 and December 31, 2012:
			September 30, 2013
			Less than 12 months								12 months or more							Total
	(unaudited, dollars in thousands)		Fair Value		Unrealized			# of			Fair Value		Unrealized			# of		Fair Value			Unrealized			# of
					Losses			Securities					Losses			Securities					Losses			Securities
	Obligations of government agencies		$	54,318	$	(1,223	)		11		$	4,549	$	(33	)		1	$	58,867		$	(1,256	)		12
	Residential mortgage-backed securities and collateralized mortgage obligations of government agencies			403,983		(10,107	)		72			4,515		(68	)		6		408,498			(10,175	)		78
	Obligations of states and political subdivisions			187,215		(11,388	)		299			12,103		(726	)		13		199,318			(12,114	)		312
	Corporate debt securities			19,943		(452	)		7			2,912		(88	)		1		22,855			(540	)		8
	Total temporarily impaired securities		$	665,459	$	(23,170	)		389		$	24,079	$	(915	)		21	$	689,538		$	(24,085	)		410
			31-Dec-12
			Less than 12 months								12 months or more							Total
	(unaudited, dollars in		Fair Value		Unrealized			# of			Fair Value		Unrealized			# of		Fair Value			Unrealized			# of
	thousands)				Losses			Securities					Losses			Securities					Losses			Securities
	Obligations of government agencies		$	18,894	$	(56	)		6		$	—	$	—			—	$	18,894		$	(56	)		6
	Residential mortgage-backed securities and collateralized mortgage obligations of government agencies			38,913		(258	)		20			9,966		(126	)		10		48,879			(384	)		30
	Obligations of states and political subdivisions			72,521		(838	)		107			—		—			—		72,521			(838	)		107
	Corporate debt securities			1,526		(57	)		2			10,878		(177	)		5		12,404			(234	)		7
	Equity securities			2,838		(21	)		2			—		—			—		2,838			(21	)		2
	Total temporarily impaired securities		$	134,692	$	(1,230	)		137		$	20,844	$	(303	)		15	$	155,536		$	(1,533	)		152
Unrealized losses on debt securities in the table 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 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 of investment grade quality 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 Federal Home Loan Bank (“FHLB”) of Pittsburgh and FHLB of Cincinnati stock totaling $12.0 million and $21.3 million at September 30, 2013 and December 31, 2012, 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_Cr

Loans and the Allowance for Credit Losses	9 Months Ended
	Sep. 30, 2013
Receivables [Abstract]
Loans and the Allowance for Credit Losses	NOTE 4. LOANS AND THE ALLOWANCE FOR CREDIT LOSSES
	The following table presents the recorded investment in loans by category, net of deferred loan fees and costs of $2.6 million and $2.5 million at September 30, 2013 and December 31, 2012, respectively:
	(unaudited, in thousands)		September 30,			December 31,
			2013			2012
	Commercial real estate:
	Land and construction		$	217,036		$	193,004
	Improved property			1,650,746			1,665,341
	Total commercial real estate			1,867,782			1,858,345
	Commercial and industrial			544,202			478,025
	Residential real estate			879,703			793,702
	Home equity			283,488			277,226
	Consumer			261,363			280,464
	Total portfolio loans			3,836,538			3,687,762
	Loans held for sale			6,601			21,903
	Total loans		$	3,843,139		$	3,709,665
	The following tables summarize changes in the allowance for credit losses applicable to each category of the loan portfolio:
			Allowance for Credit Losses By Category
			For the Nine Months Ended September 30, 2013 and 2012
	(unaudited, in thousands)		Commercial			Commercial			Commercial			Residential			Home			Consumer			Deposit			Total
			Real Estate -			Real Estate -			& Industrial			Real Estate			Equity						Overdraft
			Land and			Improved
			Construction			Property
	Balance at December 31, 2012:
	Allowance for loan losses		$	3,741		$	23,614		$	9,326		$	7,182		$	2,458		$	5,557		$	821		$	52,699
	Allowance for loan commitments			27			25			215			6			49			19			—			341
	Total beginning allowance for credit losses			3,768			23,639			9,541			7,188			2,507			5,576			821			53,040
	Provision for credit losses:
	Provision for loan losses			1,179			3,066			(561	)		459			(61	)		1,457			373			5,912
	Provision for loan commitments			57			(1	)		(64	)		—			37			1			—			30
	Total provision for credit losses			1,236			3,065			(625	)		459			(24	)		1,458			373			5,942
	Charge-offs			(526	)		(5,651	)		(1,264	)		(2,092	)		(508	)		(3,018	)		(666	)		(13,725	)
	Recoveries			125			482			407			250			108			887			197			2,456
	Net charge-offs			(401	)		(5,169	)		(857	)		(1,842	)		(400	)		(2,131	)		(469	)		(11,269	)
	Balance at September 30, 2013:
	Allowance for loan losses			4,519			21,511			7,908			5,799			1,997			4,883			725			47,342
	Allowance for loan commitments			84			24			151			6			86			20			—			371
	Total ending allowance for credit losses		$	4,603		$	21,535		$	8,059		$	5,805		$	2,083		$	4,903		$	725		$	47,713
	Balance at December 31, 2011:
	Allowance for loan losses		$	4,842		$	24,748		$	11,414		$	5,638		$	1,962		$	5,410		$	796		$	54,810
	Allowance for loan commitments			74			21			323			4			33			13			—			468
	Total beginning allowance for credit losses			4,916			24,769			11,737			5,642			1,995			5,423			796			55,278
	Provision for credit losses:
	Provision for loan losses			2,089			4,573			2,619			3,629			1,192			2,330			222			16,654
	Provision for loan commitments			(11	)		5			(65	)		—			12			7			—			(52	)
	Total provision for credit losses			2,078			4,578			2,554			3,629			1,204			2,337			222			16,602
	Charge-offs			(3,777	)		(5,749	)		(3,862	)		(3,296	)		(898	)		(2,732	)		(641	)		(20,955	)
	Recoveries			591			755			288			288			17			804			224			2,967
	Net charge-offs			(3,186	)		(4,994	)		(3,574	)		(3,008	)		(881	)		(1,928	)		(417	)		(17,988	)
	Balance at September 30, 2012:
	Allowance for loan losses			3,745			24,327			10,459			6,259			2,273			5,812			601			53,476
	Allowance for loan commitments			63			26			258			4			45			20			—			416
	Total ending allowance for credit losses		$	3,808		$	24,353		$	10,717		$	6,263		$	2,318		$	5,832		$	601		$	53,892
	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
	(unaudited, in thousands)		Commercial			Commercial			Commercial			Residential			Home			Consumer			Overdraft			Total
			Real Estate-			Real Estate-			and Industrial			Real Estate			Equity
			Land and			Improved
			Construction			Property
	September 30, 2013
	Allowance for credit losses:
	Allowance for loans individually evaluated for impairment		$	849		$	464		$	—		$	—		$	—		$	—		$	—		$	1,313
	Allowance for loans collectively evaluated for impairment			3,670			21,047			7,908			5,799			1,997			4,883			725			46,029
	Allowance for loan commitments			84			24			151			6			86			20			—			371
	Total allowance for credit losses		$	4,603		$	21,535		$	8,059		$	5,805		$	2,083		$	4,903		$	725		$	47,713
Portfolio loans:
Individually evaluated for impairment (1)		$	1,948		$	2,801		$	208		$	—		$	—		$	—		$	—		$	4,957
Collectively evaluated for impairment			215,088			1,647,945			543,994			879,703			283,488			261,363			—			3,831,581
Total portfolio loans		$	217,036		$	1,650,746		$	544,202		$	879,703		$	283,488		$	261,363		$	—		$	3,836,538
December 31, 2012
Allowance for credit losses:
Allowance for loans individually evaluated for impairment		$	832		$	911		$	—		$	—		$	—		$	—		$	—		$	1,743
Allowance for loans collectively evaluated for impairment			2,909			22,703			9,326			7,182			2,458			5,557			821			50,956
Allowance for loan commitments			27			25			215			6			49			19			—			341
Total allowance for credit losses		$	3,768		$	23,639		$	9,541		$	7,188		$	2,507		$	5,576		$	821		$	53,040
Portfolio loans:
Individually evaluated for impairment (1)		$	2,545		$	6,987		$	—		$	—		$	—		$	—		$	—		$	9,532
Collectively evaluated for impairment			190,459			1,658,354			478,025			793,702			277,226			280,464			—			3,678,230
Total portfolio loans		$	193,004		$	1,665,341		$	478,025		$	793,702		$	277,226		$	280,464		$	—		$	3,687,762
-1	Commercial loans greater than $1 million that are reported as non-accrual or as a troubled debt restructuring (“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. Other 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 descriptions of risk grades apply to commercial real estate and commercial and industrial loans:
Excellent or minimal risk loans are fully secured by liquid or readily marketable collateral and therefore have virtually no risk of loss. Good or desirable risk loans are extended in the normal course of business to creditworthy borrowers that exhibit a history of positive financial results that are at least comparable to the average for their industry or type of real estate. These loans are expected to perform satisfactorily during most economic cycles and there are no significant external factors that are expected to adversely affect these borrowers more than others in the same industry. Any minor unfavorable characteristics of these loans are outweighed or mitigated by strong positive factors including but not limited to adequate secondary sources of repayment or guarantees.
Fair or acceptable risk loans have a somewhat higher credit risk profile due to specific weaknesses or uncertainties that could adversely impact repayment capacity. Loans in this category generally warrant additional attention or monitoring, or a more rigid loan structure. These loans represent the maximum level of risk accepted in the normal course of lending. Specific issues that may warrant this grade include financial results that are less favorable than the average for the borrower’s industry or type of real estate, cyclical financial results, loans based on projections that have a reasonable probability of being achieved, start-up businesses, construction projects, and other external factors that indicate a higher level of credit risk. Loans that are underwritten primarily on the basis of the repayment capacity or financial condition of guarantors may also be assigned this grade.
Criticized or marginal loans are currently protected but have weaknesses, which, if not corrected, may inadequately protect WesBanco Bank, Inc. (the “Bank”) 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
(unaudited, in thousands)		Commercial			Commercial			Commercial			Total
		Real Estate-			Real Estate-			& Industrial			Commercial
		Land and			Improved						Loans
		Construction			Property
As of September 30, 2013
Excellent - minimal risk		$	—		$	684		$	73,706		$	74,390
Good - desirable risk			32,271			716,005			184,614			932,890
Fair - acceptable risk			172,558			827,814			263,033			1,263,405
Criticized - marginal			6,859			55,445			14,138			76,442
Classified - substandard			5,348			50,798			8,711			64,857
Classified - doubtful			—			—			—			—
Total		$	217,036		$	1,650,746		$	544,202		$	2,411,984
As of December 31, 2012
Excellent - minimal risk		$	—		$	789		$	64,255		$	65,044
Good - desirable risk			38,292			701,447			152,853			892,592
Fair - acceptable risk			136,643			826,790			242,564			1,205,997
Criticized - marginal			10,573			66,906			9,298			86,777
Classified - substandard			7,496			69,409			9,055			85,960
Classified - doubtful			—			—			—			—
Total		$	193,004		$	1,665,341		$	478,025		$	2,336,370
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 $14.6 million at September 30, 2013 and $17.9 million at December 31, 2012, of which $2.2 and $4.9 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.
The following tables summarize the age analysis of all categories of loans:
		Age Analysis of Loans
(unaudited, in thousands)		Current			30-59			60-89			90 Days			Total			Total Loans			90 Days
					Days			Days			or More			Past Due						or More
					Past Due			Past Due			Past Due									Past Due and
																				Accruing (1)
As of September 30, 2013
Commercial real estate:
Land and construction		$	213,429		$	38		$	—		$	3,569		$	3,607		$	217,036		$	248
Improved property			1,633,805			2,211			2,850			11,880			16,941			1,650,746			541
Total commercial real estate			1,847,234			2,249			2,850			15,449			20,548			1,867,782			789
Commercial and industrial			539,917			435			1,801			2,049			4,285			544,202			68
Residential real estate			864,580			1,799			3,606			9,718			15,123			879,703			1,601
Home equity			279,803			1,579			491			1,615			3,685			283,488			307
Consumer			257,565			2,870			436			492			3,798			261,363			278
Total portfolio loans			3,789,099			8,932			9,184			29,323			47,439			3,836,538			3,043
Loans held for sale			6,601			—			—			—			—			6,601			—
Total loans		$	3,795,700		$	8,932		$	9,184		$	29,323		$	47,439		$	3,843,139		$	3,043
Non-performing loans included above are as follows:
Non-accrual loans		$	10,493		$	1,175		$	655		$	25,837		$	27,667		$	38,160
TDRs accruing interest (1)			14,362			85			590			443			1,118			15,480
As of December 31, 2012
Commercial real estate:
Land and construction		$	189,072		$	1,470		$	—		$	2,462		$	3,932		$	193,004		$	—
Improved property			1,643,833			5,722			2,224			13,562			21,508			1,665,341			338
Total commercial real estate			1,832,905			7,192			2,224			16,024			25,440			1,858,345			338
Commercial and industrial			475,186			283			412			2,144			2,839			478,025			98
Residential real estate			774,006			4,231			4,833			10,632			19,696			793,702			3,199
Home equity			274,235			1,352			197			1,442			2,991			277,226			722
Consumer			273,329			4,655			1,123			1,357			7,135			280,464			937
Total portfolio loans			3,629,661			17,713			8,789			31,599			58,101			3,687,762			5,294
Loans held for sale			21,903			—			—			—			—			21,903			—
Total loans		$	3,651,564		$	17,713		$	8,789		$	31,599		$	58,101		$	3,709,665		$	5,294
Non-performing loans included above are as follows:
Non-accrual loans		$	11,724		$	591		$	1,747		$	25,310		$	27,648		$	39,372
TDRs accruing interest (1)			21,665			794			827			995			2,616			24,281
-1	Loans 90 days or more past due and accruing interest exclude TDRs 90 days or more past due and accruing interest.
Impaired Loans — 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 generally included all non-accrual loans and TDRs.
Loans are generally placed on non-accrual status when they become past due 90 days or more unless they are both well-secured and in the process of collection. Loans may also be placed on non-accrual when full collection of principal is in doubt even if payments on such loans remain current, or may remain on non-accrual if they are 90 days or more past due but subsequently brought current and maintained current for at least six consecutive months.
Loans are categorized as TDRs when the Bank, for economic or legal reasons related to a borrower’s financial difficulties, grants a concession to the borrower that it would not otherwise consider.
The following tables summarize impaired loans:
		Impaired Loans
		September 30, 2013									December 31, 2012
(unaudited, in thousands)		Unpaid			Recorded			Related			Unpaid			Recorded			Related
		Principal			Investment			Allowance			Principal			Investment			Allowance
		Balance  (1)									Balance  (1)
With no related specific allowance recorded:
Commercial real estate:
Land and construction		$	3,312		$	3,212		$	—		$	9,278		$	5,577		$	—
Improved property			22,643			20,572			—			27,515			24,455			—
Commercial and industrial			4,145			3,569			—			4,546			4,019			—
Residential real estate			22,000			20,294			—			22,146			20,269			—
Home equity			2,764			2,527			—			2,437			2,207			—
Consumer			1,553			1,318			—			1,757			1,517			—
Total impaired loans without a specific allowance			56,417			51,492			—			67,679			58,044			—
With a specific allowance recorded:
Commercial real estate:
Land and construction			1,463			1,463			849			1,627			1,627			832
Improved property			685			685			464			4,098			3,982			911
Total impaired loans with a specific allowance			2,148			2,148			1,313			5,725			5,609			1,743
Total impaired loans		$	58,565		$	53,640		$	1,313		$	73,404		$	63,653		$	1,743
(1)	The difference between the unpaid principal balance and the recorded investment generally reflects amounts that have been previously charged-off.
		Impaired Loans
		For the Three Months Ended												For the Nine Months Ended
		September 30, 2013						September 30, 2012						September 30, 2013						September 30, 2012
(unaudited, in thousands)		Average			Interest			Average			Interest			Average			Interest			Average			Interest
		Recorded			Income			Recorded			Income			Recorded			Income			Recorded			Income
		Investment			Recognized			Investment			Recognized			Investment			Recognized			Investment			Recognized
With no related specific allowance recorded:
Commercial real estate:
Land and construction		$	4,181		$	—		$	7,865		$	21		$	5,049		$	89		$	9,923		$	193
Improved Property			22,777			92			25,636			160			23,471			408			29,503			442
Commercial and industrial			3,643			26			5,683			37			3,884			87			7,005			96
Residential real estate			19,487			217			13,022			64			19,872			582			14,588			198
Home equity			2,278			20			1,008			4			2,201			50			1,104			6
Consumer			1,361			28			169			—			1,425			77			221			1
Total impaired loans without a specific allowance			53,727			383			53,383			286			55,902			1,293			62,344			936
With a specific allowance recorded:
Commercial real estate:
Land and construction			1,500			6			2,211			40			1,543			28			3,204			40
Improved Property			2,765			—			8,040			45			3,251			—			8,239			225
Total impaired loans with a specific allowance			4,265			6			10,251			85			4,794			28			11,443			265
Total impaired loans		$	57,992		$	389		$	63,634		$	371		$	60,696		$	1,321		$	73,787		$	1,201
The following tables present the recorded investment in non-accrual loans and TDRs:
		Non-accrual Loans (1)
(unaudited, in thousands)		September 30,			December 31,
		2013			2012
Commercial real estate:
Land and construction		$	4,675		$	4,668
Improved property			18,105			18,239
Total commercial real estate			22,780			22,907
Commercial and industrial			3,014			3,387
Residential real estate			10,085			11,247
Home equity			1,636			1,184
Consumer			645			647
Total		$	38,160		$	39,372
(1)	Total non-accrual loans include certain loans that are also restructured. Such loans are also set forth in the following table as non-accrual TDRs.
		TDRs
		September 30, 2013									December 31, 2012
(unaudited, in thousands)		Accruing			Non-Accrual			Total			Accruing			Non-accrual			Total
Commercial real estate:
Land and construction		$	—		$	4,056		$	4,056		$	2,537		$	2,935		$	5,472
Improved property			3,152			4,550			7,702			10,198			6,452			16,650
Total commercial real estate			3,152			8,606			11,758			12,735			9,387			22,122
Commercial and industrial			555			418			973			632			728			1,360
Residential real estate			10,209			3,190			13,399			9,022			4,077			13,099
Home equity			891			384			1,275			1,022			519			1,541
Consumer			673			322			995			870			290			1,160
Total		$	15,480		$	12,920		$	28,400		$	24,281		$	15,001		$	39,282
TDRs decreased from December 31, 2012 primarily due to principal reductions and loan sales. The increase in the number of TDR modifications and the number of defaults over the prior year resulted from the implementation of a regulatory requirement in December 2012, to include as TDRs mortgage, home equity and consumer loans discharged in bankruptcy.
As of September 30, 2013, there was one TDR greater than $1.0 million, which was non-accrual, representing $1.5 million or 5.3% of total TDRs, with specific reserves of $0.8 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.
The following tables present details related to loans identified as TDRs during the three and nine months ended September 30, 2013 and 2012, respectively:
		New TDRs (1)
		For the Three Months Ended
		30-Sep-13									30-Sep-12
(unaudited, dollars in thousands)		Number of			Pre-			Post-			Number of			Pre-			Post-
		Modifications			Modification			Modification			Modifications			Modification			Modification
					Outstanding			Outstanding						Outstanding			Outstanding
					Recorded			Recorded						Recorded			Recorded
					Investment			Investment						Investment			Investment
Commercial real estate:
Land and construction			1		$	66		$	65			—		$	—		$	—
Improved Property			1			49			49			1			1,073			917
Total commercial real estate			2			115			114			1			1,073			917
Commercial and industrial			1			14			14			—			—			—
Residential real estate			8			307			280			1			323			323
Home equity			2			75			52			—			—			—
Consumer			9			98			92			—			—			—
Total			22		$	609		$	552			2		$	1,396		$	1,240
(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.
		New TDRs (1)
		For the Nine Months Ended
		30-Sep-13									30-Sep-12
(unaudited, dollars in thousands)		Number of			Pre-			Post-			Number of			Pre-			Post-
		Modifications			Modification			Modification			Modifications			Modification			Modification
					Outstanding			Outstanding						Outstanding			Outstanding
					Recorded			Recorded						Recorded			Recorded
					Investment			Investment						Investment			Investment
Commercial real estate:
Land and construction			2		$	366		$	359			1		$	516		$	516
Improved Property			6			568			395			9			2,741			2,162
Total commercial real estate			8			934			754			10			3,257			2,678
Commercial and industrial			7			164			161			2			40			37
Residential real estate			24			2,180			2,094			7			883			896
Home equity			3			91			64			—			—			—
Consumer			13			143			120			—			—			—
Total			55		$	3,512		$	3,193			19		$	4,180		$	3,611
(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 tables summarize TDRs which defaulted (defined as past due 90 days or more) during the three and nine months ended September 30, 2013 and 2012 that were restructured within the last twelve months prior to September 30, 2013 and 2012:
		Defaulted TDRs (1)
		For the Three Months Ended
		September 30, 2013						September 30, 2012
(unaudited, dollars in thousands)		Number of			Recorded			Number of			Recorded
		Defaults			Investment			Defaults			Investment
Commercial real estate:
Land and construction			—		$	—			—		$	—
Improved property			—			—			—			—
Total commercial real estate			—			—			—			—
Commercial and industrial			—			—			1			45
Residential real estate			8			451			—			—
Home equity			1			20			—			—
Consumer			3			37			—			—
Total			12		$	508			1		$	45
(1)	Excludes loans that were either charged-off or cured by period end. The recorded investment is as of September 30, 2013 and 2012.
		Defaulted TDRs (1)
		For the Nine Months Ended
		September 30, 2013						September 30, 2012
(unaudited, dollars in thousands)		Number of			Recorded			Number of			Recorded
		Defaults			Investment			Defaults			Investment
Commercial real estate:
Land and construction			—		$	—			—		$	—
Improved property			1			45			8			2,018
Total commercial real estate			1			45			8			2,018
Commercial and industrial			2			293			2			211
Residential real estate			24			1,624			—			—
Home equity			5			107			—			—
Consumer			3			37			—			—
Total			35		$	2,106			10		$	2,229
(1)	Excludes loans that were either charged-off or cured by period end. The recorded investment is as of September 30, 2013 and 2012.
TDRs that defaulted during the nine month period and that were restructured within the last twelve months represented 7.4% of the total TDR balance at September 30, 2013. These loans are placed on non-accrual status unless they are both well-secured and in the process of collection. At September 30, 2013, only two loans in the tables above were accruing interest.
The following table summarizes other real estate owned and repossessed assets included in other assets:
(unaudited, in thousands)		September 30,			December 31,
		2013			2012
Other real estate owned		$	4,871		$	5,741
Repossessed assets			313			247
Total other real estate owned and repossessed assets		$	5,184		$	5,988

Federal_Home_Loan_Bank_Borrowi

Federal Home Loan Bank Borrowings	9 Months Ended
	Sep. 30, 2013
Banking And Thrift [Abstract]
Federal Home Loan Bank Borrowings	NOTE 5. FEDERAL HOME LOAN BANK 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 September 30, 2013 and December 31, 2012, WesBanco had FHLB borrowings of $59.9 million and $111.2 million, with a weighted-average interest rate of 2.72% and 3.04%, respectively. The decline in borrowings from December 31, 2012 was due to scheduled maturities. 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 $12.0 million at September 30, 2013 and $21.3 million at December 31, 2012 is also pledged as collateral on these advances. The remaining maximum borrowing capacity by WesBanco with the FHLB at September 30, 2013 and December 31, 2012 was estimated to be approximately $1.5 billion and $1.3 billion, respectively.
	Certain FHLB advances contain call features, which allow the FHLB to call the outstanding balance or convert a fixed rate borrowing to a variable rate advance if the strike rate goes beyond a certain predetermined rate. The probability that these advances will be called depends primarily on the level of related interest rates during the call period. Of the $59.9 million outstanding at September 30, 2013, $6.0 million in FHLB convertible advances are subject to call or conversion to a variable rate advance by the FHLB.
	The following table presents the aggregate annual maturities and weighted-average interest rates of FHLB borrowings at September 30, 2013 based on their contractual maturity dates and effective interest rates:
	(unaudited, dollars in thousands)	Scheduled		Weighted
	Year	Maturity		Average Rate
	2013	$	20,144		0.55	%
	2014		16,038		3.4	%
	2015		888		4.69	%
	2016		83		4.35	%
	2017		15,641		3.77	%
	2018 and thereafter		7,124		4.75	%
	Total	$	59,918		2.72	%

Pension_Plan

Pension Plan	9 Months Ended
	Sep. 30, 2013
Compensation And Retirement Disclosure [Abstract]
Pension Plan	NOTE 6. PENSION PLAN
	The following table presents the net periodic pension cost for WesBanco’s Defined Benefit Pension Plan (the “Plan”) and the related components:
		For the Three Months Ended						For the Nine Months Ended
		September 30,						September 30,
	(unaudited, in thousands)	2013			2012			2013			2012
	Service cost - benefits earned during year	$	742		$	688		$	2,398		$	2,049
	Interest cost on projected benefit obligation		1,015			976			3,092			2,907
	Expected return on plan assets		(1,485	)		(1,393	)		(4,525	)		(4,149	)
	Amortization of prior service cost		11			11			34			34
	Amortization of net loss		906			575			2,626			1,712
	Net periodic pension cost	$	1,189		$	857		$	3,625		$	2,553
	The Plan covers all employees of WesBanco and its subsidiaries who were hired on or before August 1, 2007 who satisfy minimum age and length of service requirements, and is not available to employees hired after such date.
	A minimum required contribution of $3.7 million is due for 2013 which will be partially funded by the Plan’s $23.6 million available credit balance. A contribution of $2.5 million was made in July 2013 and an additional $2.5 million is expected to be funded in December 2013.

Fair_Value_Measurement

Fair Value Measurement	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]
Fair Value Measurement	NOTE 7. 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:
	Securities available-for-sale: The fair value of securities available-for-sale which are measured on a recurring basis are determined primarily by obtaining quoted prices on nationally recognized securities exchanges or matrix pricing, which is a mathematical technique used widely in the industry to value debt securities without relying exclusively on quoted prices for the specific securities but rather by relying on the securities’ relationship to other similar securities. These securities are classified within level 1 or 2 in the fair value hierarchy. Certain equity securities that are lightly traded in over-the-counter markets are classified as level 2 in the fair value hierarchy, as quoted market prices may not be available on the fair value measurement date. Positions that are not traded in active markets for which valuations are generated using assumptions not observable in the market or management’s best estimate are classified within level 3 of the fair value hierarchy. This includes certain specific municipal debt issues for which the credit quality and discount rate must be estimated.
	We may be required from time to time to measure certain assets at fair value on a nonrecurring basis in accordance with GAAP. These adjustments to fair value usually result from application of lower-of-cost-or-market accounting or write-downs of individual assets.
	Impaired loans: Impaired loans are carried at the lower of cost or the fair value of the collateral for collateral-dependent loans. Collateral may be in the form of real estate or business assets including equipment, inventory and accounts receivable. The use of independent appraisals, discounted cash flow models and management’s best judgment are significant inputs in arriving at the fair value measure of the underlying collateral and impaired loans are therefore classified within level 3 of the fair value hierarchy.
	Other real estate owned and repossessed assets: Other real estate owned and repossessed assets are carried at the lower of the investment in the assets or the fair value of the assets less estimated selling costs. The use of independent appraisals and management’s best judgment are significant inputs in arriving at the fair value measure of the underlying collateral, and therefore other real estate owned and repossessed assets are classified within level 3 of the fair value hierarchy.
	Mortgage servicing rights: The fair value of mortgage servicing rights is based on an independent valuation model that calculates the present value of estimated net servicing income. The valuation model incorporates assumptions based on management’s best judgment that are significant inputs to the discounting calculations. If the carrying value exceeds fair value, they are considered impaired and are classified within level 3 of the fair value hierarchy as a result.
	Loans held for sale: Loans held for sale are carried, in aggregate, at the lower of cost or fair value. The use of a valuation model using quoted prices of similar instruments are significant inputs in arriving at the fair value and therefore loans held for sale are classified within level 2 of the fair value hierarchy.
	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 September 30, 2013 and December 31, 2012:
					September 30, 2013
					Fair Value Measurements Using:
	(unaudited, in thousands)		September 30,		Quoted Prices in			Significant Other		Significant
			2013		Active Markets			Observable		Unobservable
					for Identical			Inputs		Inputs
					Assets (Level  1)			(Level 2)		(Level 3)
	Recurring fair value measurements
	Securities - available-for-sale
	Obligations of government agencies		$	70,657	$	—		$	70,657	$	—
	Residential mortgage-backed securities and collateralized mortgage obligations of government agencies			681,011		—			681,011		—
	Obligations of state and political subdivisions			128,232		—			128,232		—
	Corporate debt securities			41,582		—			41,582		—
	Equity securities			11,973		9,443			2,530		—
	Total securities - available-for-sale		$	933,455	$	9,443		$	924,012	$	—
	Total recurring fair value measurements		$	933,455	$	9,443		$	924,012	$	—
	Nonrecurring fair value measurements
	Impaired loans		$	835	$	—		$	—	$	835
	Other real estate owned and repossessed assets			5,184		—			—		5,184
	Mortgage servicing rights			897		—			—		897
	Loans held for sale			6,601		—			6,601		—
	Total nonrecurring fair value measurements		$	13,517	$	—		$	6,601	$	6,916
					31-Dec-12
					Fair Value Measurements Using:
	(unaudited, in thousands)		December 31,		Quoted Prices in			Significant Other		Significant
			2012		Active Markets			Observable		Unobservable
					for Identical			Inputs		Inputs
					Assets (Level 1)			(Level 2)		(Level 3)
	Recurring fair value measurements
	Securities - available-for-sale
	Obligations of government agencies		$	96,612	$	—		$	96,612	$	—
	Residential mortgage-backed securities and collateralized mortgage obligations of government agencies			732,210		—			732,210		—
	Obligations of state and political subdivisions			148,635		—			148,612		23
	Corporate debt securities			32,685		—			32,685		—
	Equity securities			11,102		9,059			2,043		—
	Total securities - available-for-sale		$	1,021,244	$	9,059		$	1,012,162	$	23
	Total recurring fair value measurements		$	1,021,244	$	9,059		$	1,012,162	$	23
	Nonrecurring fair value measurements
	Impaired loans		$	3,866	$	—		$	—	$	3,866
	Other real estate owned and repossessed assets			5,988		—			—		5,988
	Mortgage servicing rights			825		—			—		825
	Loans held for sale			21,903		—			21,903		—
	Total nonrecurring fair value measurements		$	32,582	$	—		$	21,903	$	10,679
	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 transfers between level 1 and level 2 for the nine months ended September 30, 2013.
	The following tables present 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
	(unaudited, dollars in thousands)		Fair Value		Valuation Techniques		Unobservable Input	Range (Weighted Average)
			Estimate
	September 30, 2013:
	Impaired loans		$	835	Appraisal of collateral (1)		Appraisal adjustments (2)	0% to (43.4)% / (15.4)%
							Liquidation expenses (2)	0% to (8.0)% / (5.0)%
	Other real estate owned and repossessed assets			5,184	Appraisal of collateral (1),  (3)
	Mortgage servicing rights			897	Discounted cash flow		Remaining term	2.6 yrs to 26.0 yrs / 15.1 yrs
							Discount rate	9.0% to 12.0% / 9.8%
December 31, 2012:
Impaired loans		$	3,866	Appraisal of collateral (1)		Appraisal adjustments (2)	0% to (50.8%) / (13.7%)
						Liquidation expenses (2)	(3.9%) to (8.0%) / (6.8%)
Other real estate owned and repossessed assets			5,988	Appraisal of collateral (1), (3)
Mortgage servicing rights			825	Discounted cash flow		Remaining term	2.8 yrs to 27.0 yrs / 15.8 yrs
						Discount rate	9.0% to 12.0% / 9.8%
-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:
							Fair Value Measurements
(unaudited, in thousands)		Carrying		Fair Value			Quoted Prices in		Significant Other		Significant
		Amount		Estimate			Active  Markets		Observable		Unobservable
							for Identical		Inputs (Level 2)		Inputs
							Assets (Level 1)				(Level 3)
September 30, 2013:
Financial Assets
Cash and due from banks		$	145,639	$	145,639		$	145,639	$	—	$	—
Securities available-for-sale			933,455		933,455			9,443		924,012		—
Securities held-to-maturity			602,588		607,215			—		606,462		753
Net loans			3,789,196		3,720,889			—		—		3,720,889
Loans held for sale			6,601		6,601			—		6,601		—
Accrued interest receivable			19,903		19,903			19,903		—		—
Bank owned life insurance			120,457		120,457			120,457		—		—
Financial Liabilities
Deposits			5,060,442		5,075,556			3,421,995		1,653,561		—
Federal Home Loan Bank borrowings			59,918		63,338			—		63,338		—
Other borrowings			124,179		126,973			77,746		49,227		—
Junior subordinated debt			106,127		66,390			—		66,390		—
Accrued interest payable			3,535		3,535			3,535		—		—
December 31, 2012:
Financial Assets
Cash and due from banks		$	125,605	$	125,605		$	125,605	$	—	$	—
Securities available-for-sale			1,021,244		1,021,244			9,059		1,012,162		23
Securities held-to-maturity			602,509		639,273			—		638,469		804
Net loans			3,635,063		3,600,068			—		—		3,600,068
Loans held for sale			21,903		21,903			—		21,903		—
Accrued interest receivable			19,354		19,354			19,354		—		—
Bank owned life insurance			119,671		119,671			119,671		—		—
Financial Liabilities
Deposits			4,944,284		4,963,356			3,294,664		1,668,692		—
Federal Home Loan Bank borrowings			111,187		114,461			—		114,461		—
Other borrowings			142,971		142,753			95,768		46,985		—
Junior subordinated debt			113,832		64,624			—		64,624		—
Accrued interest payable			3,856		3,856			3,856		—		—
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: The carrying amount for cash and due from banks is a reasonable estimate of fair value.
Securities held-to-maturity: Fair values for securities held-to-maturity are determined in the same manner as securities available-for-sale which is described above.
Net loans: Fair values for loans are estimated using a discounted cash flow methodology. The discount rates take into account interest rates currently being offered to customers for loans with similar terms, and the credit risk associated with the loan and market factors, including liquidity. The valuation of the loan portfolio reflects discounts that WesBanco believes are consistent with transactions occurring in the marketplace for both performing and distressed loan types. The carrying value that fair value is compared to is net of the allowance for loan losses and other associated premiums and discounts. Due to the significant judgment involved in evaluating credit quality, loans are classified within level 3 of the fair value hierarchy.
Accrued interest receivable: The carrying amount of accrued interest receivable approximates its fair value.
Bank-owned life insurance: The carrying value of bank-owned life insurance represents the net cash surrender value of the underlying insurance policies, should these policies be terminated. Management believes that the carrying value approximates its fair value.
Deposits: The carrying amount is considered a reasonable estimate of fair value for demand, savings and other variable rate deposit accounts. The fair value of fixed maturity certificates of deposit is estimated by a discounted cash flow method using the rates currently offered for deposits of similar remaining maturities.
Federal Home Loan Bank borrowings: The fair value of FHLB borrowings is based on rates currently available to WesBanco for borrowings with similar terms and remaining maturities.
Other borrowings: The carrying amount of federal funds purchased and overnight sweep accounts generally approximate fair value. Other repurchase agreements are based on quoted market prices if available. If market prices are not available for certain fixed and adjustable rate repurchase agreements, then quoted market prices of similar instruments are used.
Junior subordinated debt owed to unconsolidated subsidiary trusts: Due to the pooled nature of these instruments, which are not actively traded, estimated fair value is based on broker prices from recent similar sales.
Accrued interest payable: The carrying amount of accrued interest payable approximates its fair value.
Off-balance sheet financial instruments: Off-balance sheet financial instruments consist of commitments to extend credit including letters of credit. Fair values for commitments to extend credit are estimated using the fees currently charged to enter into similar agreements, taking into account the remaining terms of the agreements and the present credit standing of the counterparties. The estimated fair value of the commitments to extend credit and letters of credit are insignificant and therefore are not presented in the above tables.

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Income	9 Months Ended
	Sep. 30, 2013
Equity [Abstract]
Accumulated Other Comprehensive Income	NOTE 8. ACCUMULATED OTHER COMPREHENSIVE INCOME
	The activity in accumulated other comprehensive income for the nine months ended September 30, 2013 and 2012 is as follows:
			Accumulated Other Comprehensive Income (1)
	(unaudited, in thousands)		Defined			Unrealized Gains			Unrealized Gains			Total
			Benefit			(Losses) on			on Securities
			Pension			Securities			Transferred
			Plan			Available-for-Sale			from Available-
									for-Sale to
									Held-to-Maturity
	Balance at December 31, 2012		$	(21,401	)	$	13,032		$	2,004		$	(6,365	)
	Other comprehensive income before reclassifications			—			(13,095	)		—			(13,095	)
	Amounts reclassified from accumulated other comprehensive income			1,630			(75	)		(537	)		1,018
	Period change			1,630			(13,170	)		(537	)		(12,077	)
	Balance at September 30, 2013		$	(19,771	)	$	(138	)	$	1,467		$	(18,442	)
	Balance at December 31, 2011		$	(15,155	)	$	11,292		$	2,961		$	(902	)
	Other comprehensive income before reclassifications			—			2,506			—			2,506
	Amounts reclassified from accumulated other comprehensive income			1,044			(884	)		(745	)		(585	)
	Period change			1,044			1,622			(745	)		1,921
	Balance at September 30, 2012		$	(14,111	)	$	12,914		$	2,216		$	1,019
	(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%.
			Amounts Reclassified from Accumulated Other
			Comprehensive Income
	Details about Accumulated Other Comprehensive		For the Three Months Ended						For the Nine Months  Ended						Affected Line Item in the
	Income Components		September 30,						September 30,						Statement of Net Income
	(unaudited, in thousands)		2013			2012			2013			2012
	Securities available-for-sale (1) :
	Net securities losses/(gains) reclassified into earnings		$	10		$	(322	)	$	(119	)	$	(1,407	)	Net securities gains/(losses)
	Related income tax (benefit)/expense			(4	)		120			44			523		Provision for income taxes
	Net effect on accumulated other comprehensive income for the period			6			(202	)		(75	)		(884	)	Net of tax
	Securities held-to-maturity (1) :
	Amortization of unrealized gain			(207	)		(369	)		(857	)		(1,199	)	Interest and dividends on securities
	transferred from available-for-sale
	Related income tax expense			76			136			320			454		Provision for income taxes
	Net effect on accumulated other comprehensive income for the period			(131	)		(233	)		(537	)		(745	)	Net of tax
	Defined benefit pension plan (2) :
	Amortization of net loss and prior service costs			918			588			2,661			1,748		Employee benefits
	Related income tax expense			(338	)		(218	)		(1,031	)		(704	)	Provision for income taxes
	Net effect on accumulated other comprehensive income for the period			580			370			1,630			1,044		Net of tax
	Total reclassifications for the period		$	455		$	(65	)	$	1,018		$	(585	)	Net of tax
	-1	For additional detail related to unrealized gains on securities and related amounts reclassified from accumulated other comprehensive income see Note 3, “Securities.”
	-2	Included in the computation of net periodic pension cost. See Note 6, “Pension Plan” for additional detail.

Commitments_and_Contingent_Lia

Commitments and Contingent Liabilities	9 Months Ended
	Sep. 30, 2013
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingent Liabilities	NOTE 9. COMMITMENTS AND CONTINGENT LIABILITIES
	Commitments — In the normal course of business, WesBanco offers off-balance sheet credit arrangements to enable its customers to meet their financing objectives. Those instruments involve, to varying degrees, elements of credit and interest rate risk in excess of the amount recognized in the financial statements. WesBanco’s exposure to credit losses in the event of non-performance by the other parties to the financial instruments for commitments to extend credit and standby letters of credit is limited to the contractual amount of those instruments. WesBanco uses the same credit policies in making commitments and conditional obligations as for all other lending. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since many of the commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. The allowance for credit losses associated with commitments was $0.4 million and $0.3 million as of September 30, 2013 and December 31, 2012, respectively, and is included in other liabilities on the Consolidated Balance Sheets.
	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 immaterial as of both September 30, 2013 and December 31, 2012.
	Contingent obligations to purchase loans funded by other entities include affordable housing plan guarantees and credit 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:
	(unaudited, in thousands)	September 30,		December 31,
		2013		2012
	Lines of credit	$	913,457	$	769,525
	Loans approved but not closed		201,838		218,531
	Overdraft limits		88,025		93,654
	Letters of credit		18,922		20,078
	Contingent obligations to purchase loans funded by other entities		6,332		6,668
	Contingent Liabilities — WesBanco is a party to various legal and administrative proceedings and claims. While any litigation contains an element of uncertainty, management believes that the outcome of such proceedings or claims pending or known to be threatened will not have a material adverse effect on WesBanco’s consolidated financial position, results of operations or cash flows.

Business_Segments

Business Segments	9 Months Ended
	Sep. 30, 2013
Segment Reporting [Abstract]
Business Segments	NOTE 10. BUSINESS SEGMENTS
	WesBanco operates two reportable segments: community banking and 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 offerings, such as insurance and securities brokerage services. The trust and investment services segment offers trust services as well as various alternative investment products including mutual funds. The market value of assets managed or held in custody by the trust and investment services segment was approximately $3.5 billion and $3.2 billion at September 30, 2013 and 2012, respectively. These assets are held by WesBanco in fiduciary or agency capacities for their customers and therefore are not included as assets on WesBanco’s Consolidated Balance Sheets.
	Condensed financial information by business segment is presented below:
	(unaudited, in thousands)	Community		Trust and		Consolidated
		Banking		Investment
				Services
	For the Three Months ended September 30, 2013:
	Interest income	$	54,317	$	—	$	54,317
	Interest expense		8,186		—		8,186
	Net interest income		46,131		—		46,131
	Provision for credit losses		2,819		—		2,819
	Net interest income after provision for credit losses		43,312		—		43,312
	Non-interest income		12,262		4,854		17,116
	Non-interest expense		37,011		2,998		40,009
	Income before provision for income taxes		18,563		1,856		20,419
	Provision for income taxes		4,141		743		4,884
	Net income	$	14,422	$	1,113	$	15,535
	For the Three Months ended September 30, 2012:
	Interest income	$	52,288	$	—	$	52,288
	Interest expense		10,594		—		10,594
	Net interest income		41,694		—		41,694
	Provision for credit losses		4,497		—		4,497
	Net interest income after provision for credit losses		37,197		—		37,197
	Non-interest income		11,583		4,379		15,962
	Non-interest expense		34,134		2,656		36,790
	Income before provision for income taxes		14,646		1,723		16,369
	Provision for income taxes		2,773		690		3,463
	Net income	$	11,873	$	1,033	$	12,906
	For the Nine Months ended September 30, 2013:
	Interest income	$	163,634	$	—	$	163,634
	Interest expense		25,385		—		25,385
	Net interest income		138,249		—		138,249
	Provision for credit losses		5,942		—		5,942
	Net interest income after provision for credit losses		132,307		—		132,307
	Non-interest income		37,642		14,694		52,336
	Non-interest expense		111,384		8,872		120,256
	Income before provision for income taxes		58,565		5,822		64,387
	Provision for income taxes		13,486		2,329		15,815
	Net income	$	45,079	$	3,493	$	48,572
	For the Nine Months ended September 30, 2012:
	Interest income	$	158,514	$	—	$	158,514
	Interest expense		33,450		—		33,450
	Net interest income		125,064		—		125,064
	Provision for credit losses		16,602		—		16,602
	Net interest income after provision for credit losses		108,462		—		108,462
	Non-interest income		33,788		13,390		47,178
	Non-interest expense		100,387		8,151		108,538
	Income before provision for income taxes		41,863		5,239		47,102
	Provision for income taxes		8,112		2,096		10,208
	Net income	$	33,751	$	3,143	$	36,894
	Total non-fiduciary assets of the trust and investment services segment were $3.3 million and $2.8 million at September 30, 2013 and 2012, respectively. All goodwill and other intangible assets were allocated to the community banking segment.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]
Basis of Presentation	Basis of presentation — The accompanying unaudited interim financial statements of WesBanco, Inc. and its consolidated subsidiaries (“WesBanco”) have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with our Annual Report on Form 10-K for the year ended December 31, 2012.
	WesBanco’s interim financial statements have been prepared following the significant accounting policies disclosed in Note 1 of the Notes to the Consolidated Financial Statements of its 2012 Annual Report on Form 10-K filed with the Securities and Exchange Commission. In the opinion of management, the accompanying interim financial information reflects all adjustments, including normal recurring adjustments, necessary to present fairly WesBanco’s financial position and results of operations for each of the interim periods presented. Results of operations for interim periods are not necessarily indicative of the results of operations that may be expected for a full year.
Recent Accounting Pronouncements	Recent accounting pronouncements — In July 2013, the Financial Accounting Standards Board (the “FASB”) issued an accounting pronouncement to improve the reporting for unrecognized tax benefits when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists. The pronouncement is expected to reduce diversity in practice by providing guidance on the presentation of unrecognized tax benefits and will better reflect the manner in which an entity would settle at the reporting date any additional income taxes that would result from the disallowance of a tax position when net operating loss carryforwards, similar tax losses, or tax credit carryforwards exist. The pronouncement is effective prospectively for fiscal years, and interim periods within those years, beginning after December 15, 2013. The adoption of this pronouncement is not expected to have a material impact on WesBanco’s consolidated financial statements.
	In February 2013, the FASB issued an accounting pronouncement to improve the reporting of reclassifications out of accumulated other comprehensive income. The amendment does not change the current requirements for reporting net income or other comprehensive income in the financial statements. However, the amendment requires an entity to provide information about the amounts reclassified out of accumulated other comprehensive income by component and to include references to other disclosures. The pronouncement is effective prospectively for interim and annual reporting periods beginning after December 15, 2012. The adoption of this pronouncement did not have a material impact on WesBanco’s consolidated financial statements.
	In December 2011, the FASB issued an accounting pronouncement which requires entities to disclose both gross and net information about instruments and transactions eligible for offset in the statement of financial position, including instruments and transactions subject to master netting arrangements. The scope would include derivatives, sale and repurchase agreements and reverse sale and repurchase agreements, and securities borrowing and securities lending arrangements. The objective of this pronouncement is to enhance disclosures required by GAAP by requiring improved information about financial instruments and derivative instruments that are either offset in accordance with existing GAAP or subject to an enforceable master netting arrangement or similar agreement. This information will enable users of an entity’s financial statements to evaluate the effect or potential effect of netting arrangements on an entity’s financial position, including the effect or potential effect of rights of setoff associated with certain financial instruments and derivative instruments. In January 2013, the FASB issued an accounting pronouncement to clarify and limit the scope of the aforementioned pronouncement by more specifically defining transactions eligible for offset. The pronouncements should be applied retrospectively effective for fiscal years, and interim periods within those years, beginning on or after January 1, 2013. The adoption of these pronouncements did not have a material impact on WesBanco’s consolidated financial statements.

Earnings_Per_Common_Share_Tabl

Earnings Per Common Share (Tables)	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]
Summary of Earnings Per Common Share	Earnings per common share are calculated as follows:
		For the Three Months Ended				For the Nine Months Ended
		September 30,				September 30,
	(unaudited, in thousands, except shares and per share amounts)	2013		2012		2013		2012
	Numerator for both basic and diluted earnings per common share:
	Net income	$	15,535	$	12,906	$	48,572	$	36,894
	Denominator:
	Total average basic common shares outstanding		29,325,128		26,664,882		29,260,967		26,646,719
	Effect of dilutive stock options		87,330		7,967		67,338		4,603
	Total diluted average common shares outstanding		29,412,458		26,672,849		29,328,305		26,651,322
	Earnings per common share - basic	$	0.53	$	0.48	$	1.66	$	1.38
	Earnings per common share - diluted	$	0.53	$	0.48	$	1.66	$	1.38

Securities_Tables

Securities (Tables)	9 Months Ended
	Sep. 30, 2013
Investments Debt And Equity Securities [Abstract]
Schedule of Fair Value and Amortized Cost of Available-for-sale and Held-to-maturity Securities	The following table presents the fair value and amortized cost of available-for-sale and held-to-maturity securities:
			September 30, 2013										December 31, 2012
	(unaudited, in thousands)		Amortized		Gross			Gross			Estimated		Amortized			Gross		Gross			Estimated
			Cost		Unrealized			Unrealized			Fair		Cost			Unrealized		Unrealized			Fair
					Gains			Losses			Value					Gains		Losses			Value
	Available-for-sale
	Obligations of government agencies		$	71,893	$	20		$	(1,256	)	$	70,657	$	96,257		$	411	$	(56	)	$	96,612
	Residential mortgage-backed securities and collateralized mortgage obligations of government agencies			686,216		4,226			(9,431	)		681,011		721,824			10,690		(304	)		732,210
	Obligations of state and political subdivisions			123,423		5,069			(260	)		128,232		139,511			9,133		(9	)		148,635
	Corporate debt securities			41,819		135			(372	)		41,582		32,706			213		(234	)		32,685
	Total debt securities		$	923,351	$	9,450		$	(11,319	)	$	921,482	$	990,298		$	20,447	$	(603	)	$	1,010,142
	Equity securities			10,244		1,729			—			11,973		10,207			916		(21	)		11,102
	Total available-for-sale securities		$	933,595	$	11,179		$	(11,319	)	$	933,455	$	1,000,505		$	21,363	$	(624	)	$	1,021,244
	Held-to-maturity
	Residential mortgage-backed securities and collateralized mortgage obligations of government agencies		$	105,907	$	3,521		$	(744	)	$	108,684	$	152,872		$	6,421	$	(80	)	$	159,213
	Other residential collateralized mortgage obligations			—		—			—			—		353			8		—			361
	Obligations of state and political subdivisions			493,968		13,872			(11,854	)		495,986		449,284			31,244		(829	)		479,699
	Corporate debt securities			2,713		—			(168	)		2,545		—			—		—			—
	Total held-to-maturity securities		$	602,588	$	17,393		$	(12,766	)	$	607,215	$	602,509		$	37,673	$	(909	)	$	639,273
	Total securities		$	1,536,183	$	28,572		$	(24,085	)	$	1,540,670	$	1,603,014		$	59,036	$	(1,533	)	$	1,660,517
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 September 30, 2013. In some instances, the issuers may have the right to call or prepay obligations without penalty prior to the contractual maturity date.
			September 30, 2013
	(unaudited, in thousands)		One Year		One to			Five to			After		Mortgage-backed			Total
			or less		Five Years			Ten Years			Ten Years		and Equity
	Available-for-sale
	Obligations of government agencies		$	—	$	17,776		$	39,269		$	13,612	$	—		$	70,657
	Residential mortgage-backed securities and collateralized mortgage obligations of government agencies (1)			—		—			—			—		681,011			681,011
	Obligations of states and political subdivisions			8,388		45,121			26,389			48,334		—			128,232
	Corporate debt securities			5,075		16,198			15,553			4,756		—			41,582
	Equity securities (2)			—		—			—			—		11,973			11,973
	Total available-for-sale securities		$	13,463	$	79,095		$	81,211		$	66,702	$	692,984		$	933,455
	Held-to-maturity (3)
	Residential mortgage-backed securities and collateralized mortgage obligations of		$	—	$	—		$	—		$	—	$	108,684		$	108,684
	obligations (1)
	Obligations of states and political subdivisions			3,860		9,407			125,581			357,138		—			495,986
	Corporate debt securities			—		—			2,545			—		—			2,545
	Total held-to-maturity securities		$	3,860	$	9,407		$	128,126		$	357,138	$	108,684		$	607,215
	Total securities		$	17,323	$	88,502		$	209,337		$	423,840	$	801,668		$	1,540,670
	-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 $602.6 million.
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 September 30, 2013 and December 31, 2012:
			September 30, 2013
			Less than 12 months								12 months or more							Total
	(unaudited, dollars in thousands)		Fair Value		Unrealized			# of			Fair Value		Unrealized			# of		Fair Value			Unrealized			# of
					Losses			Securities					Losses			Securities					Losses			Securities
	Obligations of government agencies		$	54,318	$	(1,223	)		11		$	4,549	$	(33	)		1	$	58,867		$	(1,256	)		12
	Residential mortgage-backed securities and collateralized mortgage obligations of government agencies			403,983		(10,107	)		72			4,515		(68	)		6		408,498			(10,175	)		78
	Obligations of states and political subdivisions			187,215		(11,388	)		299			12,103		(726	)		13		199,318			(12,114	)		312
	Corporate debt securities			19,943		(452	)		7			2,912		(88	)		1		22,855			(540	)		8
	Total temporarily impaired securities		$	665,459	$	(23,170	)		389		$	24,079	$	(915	)		21	$	689,538		$	(24,085	)		410
			31-Dec-12
			Less than 12 months								12 months or more							Total
	(unaudited, dollars in		Fair Value		Unrealized			# of			Fair Value		Unrealized			# of		Fair Value			Unrealized			# of
	thousands)				Losses			Securities					Losses			Securities					Losses			Securities
	Obligations of government agencies		$	18,894	$	(56	)		6		$	—	$	—			—	$	18,894		$	(56	)		6
	Residential mortgage-backed securities and collateralized mortgage obligations of government agencies			38,913		(258	)		20			9,966		(126	)		10		48,879			(384	)		30
	Obligations of states and political subdivisions			72,521		(838	)		107			—		—			—		72,521			(838	)		107
	Corporate debt securities			1,526		(57	)		2			10,878		(177	)		5		12,404			(234	)		7
	Equity securities			2,838		(21	)		2			—		—			—		2,838			(21	)		2
	Total temporarily impaired securities		$	134,692	$	(1,230	)		137		$	20,844	$	(303	)		15	$	155,536		$	(1,533	)		152

Loans_and_the_Allowance_for_Cr1

Loans and the Allowance for Credit Losses (Tables)	9 Months Ended
	Sep. 30, 2013
Receivables [Abstract]
Schedule of Recorded Investment in Loans by Category	The following table presents the recorded investment in loans by category, net of deferred loan fees and costs of $2.6 million and $2.5 million at September 30, 2013 and December 31, 2012, respectively:
	(unaudited, in thousands)		September 30,			December 31,
			2013			2012
	Commercial real estate:
	Land and construction		$	217,036		$	193,004
	Improved property			1,650,746			1,665,341
	Total commercial real estate			1,867,782			1,858,345
	Commercial and industrial			544,202			478,025
	Residential real estate			879,703			793,702
	Home equity			283,488			277,226
	Consumer			261,363			280,464
	Total portfolio loans			3,836,538			3,687,762
	Loans held for sale			6,601			21,903
	Total loans		$	3,843,139		$	3,709,665
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:
			Allowance for Credit Losses By Category
			For the Nine Months Ended September 30, 2013 and 2012
	(unaudited, in thousands)		Commercial			Commercial			Commercial			Residential			Home			Consumer			Deposit			Total
			Real Estate -			Real Estate -			& Industrial			Real Estate			Equity						Overdraft
			Land and			Improved
			Construction			Property
	Balance at December 31, 2012:
	Allowance for loan losses		$	3,741		$	23,614		$	9,326		$	7,182		$	2,458		$	5,557		$	821		$	52,699
	Allowance for loan commitments			27			25			215			6			49			19			—			341
	Total beginning allowance for credit losses			3,768			23,639			9,541			7,188			2,507			5,576			821			53,040
	Provision for credit losses:
	Provision for loan losses			1,179			3,066			(561	)		459			(61	)		1,457			373			5,912
	Provision for loan commitments			57			(1	)		(64	)		—			37			1			—			30
	Total provision for credit losses			1,236			3,065			(625	)		459			(24	)		1,458			373			5,942
	Charge-offs			(526	)		(5,651	)		(1,264	)		(2,092	)		(508	)		(3,018	)		(666	)		(13,725	)
	Recoveries			125			482			407			250			108			887			197			2,456
	Net charge-offs			(401	)		(5,169	)		(857	)		(1,842	)		(400	)		(2,131	)		(469	)		(11,269	)
	Balance at September 30, 2013:
	Allowance for loan losses			4,519			21,511			7,908			5,799			1,997			4,883			725			47,342
	Allowance for loan commitments			84			24			151			6			86			20			—			371
	Total ending allowance for credit losses		$	4,603		$	21,535		$	8,059		$	5,805		$	2,083		$	4,903		$	725		$	47,713
	Balance at December 31, 2011:
	Allowance for loan losses		$	4,842		$	24,748		$	11,414		$	5,638		$	1,962		$	5,410		$	796		$	54,810
	Allowance for loan commitments			74			21			323			4			33			13			—			468
	Total beginning allowance for credit losses			4,916			24,769			11,737			5,642			1,995			5,423			796			55,278
	Provision for credit losses:
	Provision for loan losses			2,089			4,573			2,619			3,629			1,192			2,330			222			16,654
	Provision for loan commitments			(11	)		5			(65	)		—			12			7			—			(52	)
	Total provision for credit losses			2,078			4,578			2,554			3,629			1,204			2,337			222			16,602
	Charge-offs			(3,777	)		(5,749	)		(3,862	)		(3,296	)		(898	)		(2,732	)		(641	)		(20,955	)
	Recoveries			591			755			288			288			17			804			224			2,967
	Net charge-offs			(3,186	)		(4,994	)		(3,574	)		(3,008	)		(881	)		(1,928	)		(417	)		(17,988	)
	Balance at September 30, 2012:
	Allowance for loan losses			3,745			24,327			10,459			6,259			2,273			5,812			601			53,476
	Allowance for loan commitments			63			26			258			4			45			20			—			416
	Total ending allowance for credit losses		$	3,808		$	24,353		$	10,717		$	6,263		$	2,318		$	5,832		$	601		$	53,892
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
	(unaudited, in thousands)		Commercial			Commercial			Commercial			Residential			Home			Consumer			Overdraft			Total
			Real Estate-			Real Estate-			and Industrial			Real Estate			Equity
			Land and			Improved
			Construction			Property
	September 30, 2013
	Allowance for credit losses:
	Allowance for loans individually evaluated for impairment		$	849		$	464		$	—		$	—		$	—		$	—		$	—		$	1,313
	Allowance for loans collectively evaluated for impairment			3,670			21,047			7,908			5,799			1,997			4,883			725			46,029
	Allowance for loan commitments			84			24			151			6			86			20			—			371
	Total allowance for credit losses		$	4,603		$	21,535		$	8,059		$	5,805		$	2,083		$	4,903		$	725		$	47,713
	Portfolio loans:
	Individually evaluated for impairment (1)		$	1,948		$	2,801		$	208		$	—		$	—		$	—		$	—		$	4,957
	Collectively evaluated for impairment			215,088			1,647,945			543,994			879,703			283,488			261,363			—			3,831,581
	Total portfolio loans		$	217,036		$	1,650,746		$	544,202		$	879,703		$	283,488		$	261,363		$	—		$	3,836,538
	December 31, 2012
	Allowance for credit losses:
	Allowance for loans individually evaluated for impairment		$	832		$	911		$	—		$	—		$	—		$	—		$	—		$	1,743
	Allowance for loans collectively evaluated for impairment			2,909			22,703			9,326			7,182			2,458			5,557			821			50,956
	Allowance for loan commitments			27			25			215			6			49			19			—			341
	Total allowance for credit losses		$	3,768		$	23,639		$	9,541		$	7,188		$	2,507		$	5,576		$	821		$	53,040
	Portfolio loans:
	Individually evaluated for impairment (1)		$	2,545		$	6,987		$	—		$	—		$	—		$	—		$	—		$	9,532
	Collectively evaluated for impairment			190,459			1,658,354			478,025			793,702			277,226			280,464			—			3,678,230
	Total portfolio loans		$	193,004		$	1,665,341		$	478,025		$	793,702		$	277,226		$	280,464		$	—		$	3,687,762
	-1	Commercial loans greater than $1 million that are reported as non-accrual or as a troubled debt restructuring (“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
	(unaudited, in thousands)		Commercial			Commercial			Commercial			Total
			Real Estate-			Real Estate-			& Industrial			Commercial
			Land and			Improved						Loans
			Construction			Property
	As of September 30, 2013
	Excellent - minimal risk		$	—		$	684		$	73,706		$	74,390
	Good - desirable risk			32,271			716,005			184,614			932,890
	Fair - acceptable risk			172,558			827,814			263,033			1,263,405
	Criticized - marginal			6,859			55,445			14,138			76,442
	Classified - substandard			5,348			50,798			8,711			64,857
	Classified - doubtful			—			—			—			—
	Total		$	217,036		$	1,650,746		$	544,202		$	2,411,984
	As of December 31, 2012
	Excellent - minimal risk		$	—		$	789		$	64,255		$	65,044
	Good - desirable risk			38,292			701,447			152,853			892,592
	Fair - acceptable risk			136,643			826,790			242,564			1,205,997
	Criticized - marginal			10,573			66,906			9,298			86,777
	Classified - substandard			7,496			69,409			9,055			85,960
	Classified - doubtful			—			—			—			—
	Total		$	193,004		$	1,665,341		$	478,025		$	2,336,370
Summary of Age Analysis of Loan Categories	The following tables summarize the age analysis of all categories of loans:
			Age Analysis of Loans
	(unaudited, in thousands)		Current			30-59			60-89			90 Days			Total			Total Loans			90 Days
						Days			Days			or More			Past Due						or More
						Past Due			Past Due			Past Due									Past Due and
																					Accruing (1)
	As of September 30, 2013
	Commercial real estate:
	Land and construction		$	213,429		$	38		$	—		$	3,569		$	3,607		$	217,036		$	248
	Improved property			1,633,805			2,211			2,850			11,880			16,941			1,650,746			541
	Total commercial real estate			1,847,234			2,249			2,850			15,449			20,548			1,867,782			789
	Commercial and industrial			539,917			435			1,801			2,049			4,285			544,202			68
	Residential real estate			864,580			1,799			3,606			9,718			15,123			879,703			1,601
	Home equity			279,803			1,579			491			1,615			3,685			283,488			307
	Consumer			257,565			2,870			436			492			3,798			261,363			278
	Total portfolio loans			3,789,099			8,932			9,184			29,323			47,439			3,836,538			3,043
	Loans held for sale			6,601			—			—			—			—			6,601			—
	Total loans		$	3,795,700		$	8,932		$	9,184		$	29,323		$	47,439		$	3,843,139		$	3,043
	Non-performing loans included above are as follows:
	Non-accrual loans		$	10,493		$	1,175		$	655		$	25,837		$	27,667		$	38,160
	TDRs accruing interest (1)			14,362			85			590			443			1,118			15,480
	As of December 31, 2012
	Commercial real estate:
	Land and construction		$	189,072		$	1,470		$	—		$	2,462		$	3,932		$	193,004		$	—
	Improved property			1,643,833			5,722			2,224			13,562			21,508			1,665,341			338
	Total commercial real estate			1,832,905			7,192			2,224			16,024			25,440			1,858,345			338
	Commercial and industrial			475,186			283			412			2,144			2,839			478,025			98
	Residential real estate			774,006			4,231			4,833			10,632			19,696			793,702			3,199
	Home equity			274,235			1,352			197			1,442			2,991			277,226			722
	Consumer			273,329			4,655			1,123			1,357			7,135			280,464			937
	Total portfolio loans			3,629,661			17,713			8,789			31,599			58,101			3,687,762			5,294
	Loans held for sale			21,903			—			—			—			—			21,903			—
	Total loans		$	3,651,564		$	17,713		$	8,789		$	31,599		$	58,101		$	3,709,665		$	5,294
	Non-performing loans included above are as follows:
	Non-accrual loans		$	11,724		$	591		$	1,747		$	25,310		$	27,648		$	39,372
	TDRs accruing interest (1)			21,665			794			827			995			2,616			24,281
	-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
			September 30, 2013									December 31, 2012
	(unaudited, in thousands)		Unpaid			Recorded			Related			Unpaid			Recorded			Related
			Principal			Investment			Allowance			Principal			Investment			Allowance
			Balance  (1)									Balance  (1)
	With no related specific allowance recorded:
	Commercial real estate:
	Land and construction		$	3,312		$	3,212		$	—		$	9,278		$	5,577		$	—
	Improved property			22,643			20,572			—			27,515			24,455			—
	Commercial and industrial			4,145			3,569			—			4,546			4,019			—
	Residential real estate			22,000			20,294			—			22,146			20,269			—
	Home equity			2,764			2,527			—			2,437			2,207			—
	Consumer			1,553			1,318			—			1,757			1,517			—
	Total impaired loans without a specific allowance			56,417			51,492			—			67,679			58,044			—
	With a specific allowance recorded:
	Commercial real estate:
	Land and construction			1,463			1,463			849			1,627			1,627			832
	Improved property			685			685			464			4,098			3,982			911
	Total impaired loans with a specific allowance			2,148			2,148			1,313			5,725			5,609			1,743
	Total impaired loans		$	58,565		$	53,640		$	1,313		$	73,404		$	63,653		$	1,743
	(1)	The difference between the unpaid principal balance and the recorded investment generally reflects amounts that have been previously charged-off.
			Impaired Loans
			For the Three Months Ended												For the Nine Months Ended
			September 30, 2013						September 30, 2012						September 30, 2013						September 30, 2012
	(unaudited, in thousands)		Average			Interest			Average			Interest			Average			Interest			Average			Interest
			Recorded			Income			Recorded			Income			Recorded			Income			Recorded			Income
			Investment			Recognized			Investment			Recognized			Investment			Recognized			Investment			Recognized
	With no related specific allowance recorded:
	Commercial real estate:
	Land and construction		$	4,181		$	—		$	7,865		$	21		$	5,049		$	89		$	9,923		$	193
	Improved Property			22,777			92			25,636			160			23,471			408			29,503			442
	Commercial and industrial			3,643			26			5,683			37			3,884			87			7,005			96
	Residential real estate			19,487			217			13,022			64			19,872			582			14,588			198
	Home equity			2,278			20			1,008			4			2,201			50			1,104			6
	Consumer			1,361			28			169			—			1,425			77			221			1
	Total impaired loans without a specific allowance			53,727			383			53,383			286			55,902			1,293			62,344			936
	With a specific allowance recorded:
	Commercial real estate:
	Land and construction			1,500			6			2,211			40			1,543			28			3,204			40
	Improved Property			2,765			—			8,040			45			3,251			—			8,239			225
	Total impaired loans with a specific allowance			4,265			6			10,251			85			4,794			28			11,443			265
	Total impaired loans		$	57,992		$	389		$	63,634		$	371		$	60,696		$	1,321		$	73,787		$	1,201
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)
	(unaudited, in thousands)		September 30,			December 31,
			2013			2012
	Commercial real estate:
	Land and construction		$	4,675		$	4,668
	Improved property			18,105			18,239
	Total commercial real estate			22,780			22,907
	Commercial and industrial			3,014			3,387
	Residential real estate			10,085			11,247
	Home equity			1,636			1,184
	Consumer			645			647
	Total		$	38,160		$	39,372
	(1)	Total non-accrual loans include certain loans that are also restructured. Such loans are also set forth in the following table as non-accrual TDRs.
			TDRs
			September 30, 2013									December 31, 2012
	(unaudited, in thousands)		Accruing			Non-Accrual			Total			Accruing			Non-accrual			Total
	Commercial real estate:
	Land and construction		$	—		$	4,056		$	4,056		$	2,537		$	2,935		$	5,472
	Improved property			3,152			4,550			7,702			10,198			6,452			16,650
	Total commercial real estate			3,152			8,606			11,758			12,735			9,387			22,122
	Commercial and industrial			555			418			973			632			728			1,360
	Residential real estate			10,209			3,190			13,399			9,022			4,077			13,099
	Home equity			891			384			1,275			1,022			519			1,541
	Consumer			673			322			995			870			290			1,160
	Total		$	15,480		$	12,920		$	28,400		$	24,281		$	15,001		$	39,282
Loans Identified as TDRs	The following tables present details related to loans identified as TDRs during the three and nine months ended September 30, 2013 and 2012, respectively:
			New TDRs (1)
			For the Three Months Ended
			30-Sep-13									30-Sep-12
	(unaudited, dollars in thousands)		Number of			Pre-			Post-			Number of			Pre-			Post-
			Modifications			Modification			Modification			Modifications			Modification			Modification
						Outstanding			Outstanding						Outstanding			Outstanding
						Recorded			Recorded						Recorded			Recorded
						Investment			Investment						Investment			Investment
	Commercial real estate:
	Land and construction			1		$	66		$	65			—		$	—		$	—
	Improved Property			1			49			49			1			1,073			917
	Total commercial real estate			2			115			114			1			1,073			917
	Commercial and industrial			1			14			14			—			—			—
	Residential real estate			8			307			280			1			323			323
	Home equity			2			75			52			—			—			—
	Consumer			9			98			92			—			—			—
	Total			22		$	609		$	552			2		$	1,396		$	1,240
	(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.
			New TDRs (1)
			For the Nine Months Ended
			30-Sep-13									30-Sep-12
	(unaudited, dollars in thousands)		Number of			Pre-			Post-			Number of			Pre-			Post-
			Modifications			Modification			Modification			Modifications			Modification			Modification
						Outstanding			Outstanding						Outstanding			Outstanding
						Recorded			Recorded						Recorded			Recorded
						Investment			Investment						Investment			Investment
	Commercial real estate:
	Land and construction			2		$	366		$	359			1		$	516		$	516
	Improved Property			6			568			395			9			2,741			2,162
	Total commercial real estate			8			934			754			10			3,257			2,678
	Commercial and industrial			7			164			161			2			40			37
	Residential real estate			24			2,180			2,094			7			883			896
	Home equity			3			91			64			—			—			—
	Consumer			13			143			120			—			—			—
	Total			55		$	3,512		$	3,193			19		$	4,180		$	3,611
	(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.
TDRs Defaulted Later Restructured	The following tables summarize TDRs which defaulted (defined as past due 90 days or more) during the three and nine months ended September 30, 2013 and 2012 that were restructured within the last twelve months prior to September 30, 2013 and 2012:
			Defaulted TDRs (1)
			For the Three Months Ended
			September 30, 2013						September 30, 2012
	(unaudited, dollars in thousands)		Number of			Recorded			Number of			Recorded
			Defaults			Investment			Defaults			Investment
	Commercial real estate:
	Land and construction			—		$	—			—		$	—
	Improved property			—			—			—			—
	Total commercial real estate			—			—			—			—
	Commercial and industrial			—			—			1			45
	Residential real estate			8			451			—			—
	Home equity			1			20			—			—
	Consumer			3			37			—			—
	Total			12		$	508			1		$	45
	(1)	Excludes loans that were either charged-off or cured by period end. The recorded investment is as of September 30, 2013 and 2012.
			Defaulted TDRs (1)
			For the Nine Months Ended
			September 30, 2013						September 30, 2012
	(unaudited, dollars in thousands)		Number of			Recorded			Number of			Recorded
			Defaults			Investment			Defaults			Investment
	Commercial real estate:
	Land and construction			—		$	—			—		$	—
	Improved property			1			45			8			2,018
	Total commercial real estate			1			45			8			2,018
	Commercial and industrial			2			293			2			211
	Residential real estate			24			1,624			—			—
	Home equity			5			107			—			—
	Consumer			3			37			—			—
	Total			35		$	2,106			10		$	2,229
	(1)	Excludes loans that were either charged-off or cured by period end. The recorded investment is as of September 30, 2013 and 2012.
Summary of Other Real Estate Owned and Repossessed Assets	The following table summarizes other real estate owned and repossessed assets included in other assets:
	(unaudited, in thousands)		September 30,			December 31,
			2013			2012
	Other real estate owned		$	4,871		$	5,741
	Repossessed assets			313			247
	Total other real estate owned and repossessed assets		$	5,184		$	5,988

Federal_Home_Loan_Bank_Borrowi1

Federal Home Loan Bank Borrowings (Tables)	9 Months Ended
	Sep. 30, 2013
Banking And Thrift [Abstract]
Aggregate Annual Maturities and Weighted-Average Interest Rates of Federal Home Loan Bank	The following table presents the aggregate annual maturities and weighted-average interest rates of FHLB borrowings at September 30, 2013 based on their contractual maturity dates and effective interest rates:
	(unaudited, dollars in thousands)	Scheduled		Weighted
	Year	Maturity		Average Rate
	2013	$	20,144		0.55	%
	2014		16,038		3.4	%
	2015		888		4.69	%
	2016		83		4.35	%
	2017		15,641		3.77	%
	2018 and thereafter		7,124		4.75	%
	Total	$	59,918		2.72	%

Pension_Plan_Tables

Pension Plan (Tables)	9 Months Ended
	Sep. 30, 2013
Compensation And Retirement Disclosure [Abstract]
Components of Net Periodic Pension Cost	The following table presents the net periodic pension cost for WesBanco’s Defined Benefit Pension Plan (the “Plan”) and the related components:
		For the Three Months Ended						For the Nine Months Ended
		September 30,						September 30,
	(unaudited, in thousands)	2013			2012			2013			2012
	Service cost - benefits earned during year	$	742		$	688		$	2,398		$	2,049
	Interest cost on projected benefit obligation		1,015			976			3,092			2,907
	Expected return on plan assets		(1,485	)		(1,393	)		(4,525	)		(4,149	)
	Amortization of prior service cost		11			11			34			34
	Amortization of net loss		906			575			2,626			1,712
	Net periodic pension cost	$	1,189		$	857		$	3,625		$	2,553

Fair_Value_Measurement_Tables

Fair Value Measurement (Tables)	9 Months Ended
	Sep. 30, 2013
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 September 30, 2013 and December 31, 2012:
					September 30, 2013
					Fair Value Measurements Using:
	(unaudited, in thousands)		September 30,		Quoted Prices in			Significant Other		Significant
			2013		Active Markets			Observable		Unobservable
					for Identical			Inputs		Inputs
					Assets (Level  1)			(Level 2)		(Level 3)
	Recurring fair value measurements
	Securities - available-for-sale
	Obligations of government agencies		$	70,657	$	—		$	70,657	$	—
	Residential mortgage-backed securities and collateralized mortgage obligations of government agencies			681,011		—			681,011		—
	Obligations of state and political subdivisions			128,232		—			128,232		—
	Corporate debt securities			41,582		—			41,582		—
	Equity securities			11,973		9,443			2,530		—
	Total securities - available-for-sale		$	933,455	$	9,443		$	924,012	$	—
	Total recurring fair value measurements		$	933,455	$	9,443		$	924,012	$	—
	Nonrecurring fair value measurements
	Impaired loans		$	835	$	—		$	—	$	835
	Other real estate owned and repossessed assets			5,184		—			—		5,184
	Mortgage servicing rights			897		—			—		897
	Loans held for sale			6,601		—			6,601		—
	Total nonrecurring fair value measurements		$	13,517	$	—		$	6,601	$	6,916
					31-Dec-12
					Fair Value Measurements Using:
	(unaudited, in thousands)		December 31,		Quoted Prices in			Significant Other		Significant
			2012		Active Markets			Observable		Unobservable
					for Identical			Inputs		Inputs
					Assets (Level 1)			(Level 2)		(Level 3)
	Recurring fair value measurements
	Securities - available-for-sale
	Obligations of government agencies		$	96,612	$	—		$	96,612	$	—
	Residential mortgage-backed securities and collateralized mortgage obligations of government agencies			732,210		—			732,210		—
	Obligations of state and political subdivisions			148,635		—			148,612		23
	Corporate debt securities			32,685		—			32,685		—
	Equity securities			11,102		9,059			2,043		—
	Total securities - available-for-sale		$	1,021,244	$	9,059		$	1,012,162	$	23
	Total recurring fair value measurements		$	1,021,244	$	9,059		$	1,012,162	$	23
	Nonrecurring fair value measurements
	Impaired loans		$	3,866	$	—		$	—	$	3,866
	Other real estate owned and repossessed assets			5,988		—			—		5,988
	Mortgage servicing rights			825		—			—		825
	Loans held for sale			21,903		—			21,903		—
	Total nonrecurring fair value measurements		$	32,582	$	—		$	21,903	$	10,679
Schedule of Assets Measured at Fair Value on Nonrecurring Basis	The following tables present 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
	(unaudited, dollars in thousands)		Fair Value		Valuation Techniques		Unobservable Input	Range (Weighted Average)
			Estimate
	September 30, 2013:
	Impaired loans		$	835	Appraisal of collateral (1)		Appraisal adjustments (2)	0% to (43.4)% / (15.4)%
							Liquidation expenses (2)	0% to (8.0)% / (5.0)%
	Other real estate owned and repossessed assets			5,184	Appraisal of collateral (1),  (3)
	Mortgage servicing rights			897	Discounted cash flow		Remaining term	2.6 yrs to 26.0 yrs / 15.1 yrs
							Discount rate	9.0% to 12.0% / 9.8%
	December 31, 2012:
	Impaired loans		$	3,866	Appraisal of collateral (1)		Appraisal adjustments (2)	0% to (50.8%) / (13.7%)
							Liquidation expenses (2)	(3.9%) to (8.0%) / (6.8%)
	Other real estate owned and repossessed assets			5,988	Appraisal of collateral (1), (3)
	Mortgage servicing rights			825	Discounted cash flow		Remaining term	2.8 yrs to 27.0 yrs / 15.8 yrs
							Discount rate	9.0% to 12.0% / 9.8%
	-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 Value of Financial Instruments	The estimated fair values of WesBanco’s financial instruments are summarized below:
								Fair Value Measurements
	(unaudited, in thousands)		Carrying		Fair Value			Quoted Prices in		Significant Other		Significant
			Amount		Estimate			Active  Markets		Observable		Unobservable
								for Identical		Inputs (Level 2)		Inputs
								Assets (Level 1)				(Level 3)
	September 30, 2013:
	Financial Assets
	Cash and due from banks		$	145,639	$	145,639		$	145,639	$	—	$	—
	Securities available-for-sale			933,455		933,455			9,443		924,012		—
	Securities held-to-maturity			602,588		607,215			—		606,462		753
	Net loans			3,789,196		3,720,889			—		—		3,720,889
	Loans held for sale			6,601		6,601			—		6,601		—
	Accrued interest receivable			19,903		19,903			19,903		—		—
	Bank owned life insurance			120,457		120,457			120,457		—		—
	Financial Liabilities
	Deposits			5,060,442		5,075,556			3,421,995		1,653,561		—
	Federal Home Loan Bank borrowings			59,918		63,338			—		63,338		—
	Other borrowings			124,179		126,973			77,746		49,227		—
	Junior subordinated debt			106,127		66,390			—		66,390		—
	Accrued interest payable			3,535		3,535			3,535		—		—
	December 31, 2012:
	Financial Assets
	Cash and due from banks		$	125,605	$	125,605		$	125,605	$	—	$	—
	Securities available-for-sale			1,021,244		1,021,244			9,059		1,012,162		23
	Securities held-to-maturity			602,509		639,273			—		638,469		804
	Net loans			3,635,063		3,600,068			—		—		3,600,068
	Loans held for sale			21,903		21,903			—		21,903		—
	Accrued interest receivable			19,354		19,354			19,354		—		—
	Bank owned life insurance			119,671		119,671			119,671		—		—
	Financial Liabilities
	Deposits			4,944,284		4,963,356			3,294,664		1,668,692		—
	Federal Home Loan Bank borrowings			111,187		114,461			—		114,461		—
	Other borrowings			142,971		142,753			95,768		46,985		—
	Junior subordinated debt			113,832		64,624			—		64,624		—
	Accrued interest payable			3,856		3,856			3,856		—		—

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Income (Tables)	9 Months Ended
	Sep. 30, 2013
Equity [Abstract]
Components of Accumulated Other Comprehensive Income	The activity in accumulated other comprehensive income for the nine months ended September 30, 2013 and 2012 is as follows:
			Accumulated Other Comprehensive Income (1)
	(unaudited, in thousands)		Defined			Unrealized Gains			Unrealized Gains			Total
			Benefit			(Losses) on			on Securities
			Pension			Securities			Transferred
			Plan			Available-for-Sale			from Available-
									for-Sale to
									Held-to-Maturity
	Balance at December 31, 2012		$	(21,401	)	$	13,032		$	2,004		$	(6,365	)
	Other comprehensive income before reclassifications			—			(13,095	)		—			(13,095	)
	Amounts reclassified from accumulated other comprehensive income			1,630			(75	)		(537	)		1,018
	Period change			1,630			(13,170	)		(537	)		(12,077	)
	Balance at September 30, 2013		$	(19,771	)	$	(138	)	$	1,467		$	(18,442	)
	Balance at December 31, 2011		$	(15,155	)	$	11,292		$	2,961		$	(902	)
	Other comprehensive income before reclassifications			—			2,506			—			2,506
	Amounts reclassified from accumulated other comprehensive income			1,044			(884	)		(745	)		(585	)
	Period change			1,044			1,622			(745	)		1,921
	Balance at September 30, 2012		$	(14,111	)	$	12,914		$	2,216		$	1,019
	(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 Accumulated Other Comprehensive Income Component Details	Amounts Reclassified from Accumulated Other
	Comprehensive Income
	Details about Accumulated Other Comprehensive		For the Three Months Ended						For the Nine Months  Ended						Affected Line Item in the
	Income Components		September 30,						September 30,						Statement of Net Income
	(unaudited, in thousands)		2013			2012			2013			2012
	Securities available-for-sale (1) :
	Net securities losses/(gains) reclassified into earnings		$	10		$	(322	)	$	(119	)	$	(1,407	)	Net securities gains/(losses)
	Related income tax (benefit)/expense			(4	)		120			44			523		Provision for income taxes
	Net effect on accumulated other comprehensive income for the period			6			(202	)		(75	)		(884	)	Net of tax
	Securities held-to-maturity (1) :
	Amortization of unrealized gain			(207	)		(369	)		(857	)		(1,199	)	Interest and dividends on securities
	transferred from available-for-sale
	Related income tax expense			76			136			320			454		Provision for income taxes
	Net effect on accumulated other comprehensive income for the period			(131	)		(233	)		(537	)		(745	)	Net of tax
	Defined benefit pension plan (2) :
	Amortization of net loss and prior service costs			918			588			2,661			1,748		Employee benefits
	Related income tax expense			(338	)		(218	)		(1,031	)		(704	)	Provision for income taxes
	Net effect on accumulated other comprehensive income for the period			580			370			1,630			1,044		Net of tax
	Total reclassifications for the period		$	455		$	(65	)	$	1,018		$	(585	)	Net of tax
	-1	For additional detail related to unrealized gains on securities and related amounts reclassified from accumulated other comprehensive income see Note 3, “Securities.”
	-2	Included in the computation of net periodic pension cost. See Note 6, “Pension Plan” for additional detail.

Commitments_and_Contingent_Lia1

Commitments and Contingent Liabilities (Tables)	9 Months Ended
	Sep. 30, 2013
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:
	(unaudited, in thousands)	September 30,		December 31,
		2013		2012
	Lines of credit	$	913,457	$	769,525
	Loans approved but not closed		201,838		218,531
	Overdraft limits		88,025		93,654
	Letters of credit		18,922		20,078
	Contingent obligations to purchase loans funded by other entities		6,332		6,668

Business_Segments_Tables

Business Segments (Tables)	9 Months Ended
	Sep. 30, 2013
Segment Reporting [Abstract]
Financial Information by Business Segment	Condensed financial information by business segment is presented below:
	(unaudited, in thousands)	Community		Trust and		Consolidated
		Banking		Investment
				Services
	For the Three Months ended September 30, 2013:
	Interest income	$	54,317	$	—	$	54,317
	Interest expense		8,186		—		8,186
	Net interest income		46,131		—		46,131
	Provision for credit losses		2,819		—		2,819
	Net interest income after provision for credit losses		43,312		—		43,312
	Non-interest income		12,262		4,854		17,116
	Non-interest expense		37,011		2,998		40,009
	Income before provision for income taxes		18,563		1,856		20,419
	Provision for income taxes		4,141		743		4,884
	Net income	$	14,422	$	1,113	$	15,535
	For the Three Months ended September 30, 2012:
	Interest income	$	52,288	$	—	$	52,288
	Interest expense		10,594		—		10,594
	Net interest income		41,694		—		41,694
	Provision for credit losses		4,497		—		4,497
	Net interest income after provision for credit losses		37,197		—		37,197
	Non-interest income		11,583		4,379		15,962
	Non-interest expense		34,134		2,656		36,790
	Income before provision for income taxes		14,646		1,723		16,369
	Provision for income taxes		2,773		690		3,463
	Net income	$	11,873	$	1,033	$	12,906
	For the Nine Months ended September 30, 2013:
	Interest income	$	163,634	$	—	$	163,634
	Interest expense		25,385		—		25,385
	Net interest income		138,249		—		138,249
	Provision for credit losses		5,942		—		5,942
	Net interest income after provision for credit losses		132,307		—		132,307
	Non-interest income		37,642		14,694		52,336
	Non-interest expense		111,384		8,872		120,256
	Income before provision for income taxes		58,565		5,822		64,387
	Provision for income taxes		13,486		2,329		15,815
	Net income	$	45,079	$	3,493	$	48,572
	For the Nine Months ended September 30, 2012:
	Interest income	$	158,514	$	—	$	158,514
	Interest expense		33,450		—		33,450
	Net interest income		125,064		—		125,064
	Provision for credit losses		16,602		—		16,602
	Net interest income after provision for credit losses		108,462		—		108,462
	Non-interest income		33,788		13,390		47,178
	Non-interest expense		100,387		8,151		108,538
	Income before provision for income taxes		41,863		5,239		47,102
	Provision for income taxes		8,112		2,096		10,208
	Net income	$	33,751	$	3,143	$	36,894

Earnings_Per_Common_Share_Summ

Earnings Per Common Share - Summary of Earnings Per Common Share (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Numerator for both basic and diluted earnings per common share:
Net income	$15,535	$12,906	$48,572	$36,894
Denominator:
Total average basic common shares outstanding	29,325,128	26,664,882	29,260,967	26,646,719
Effect of dilutive stock options	87,330	7,967	67,338	4,603
Total diluted average common shares outstanding	29,412,458	26,672,849	29,328,305	26,651,322
Earnings per common share - basic	$0.53	$0.48	$1.66	$1.38
Earnings per common share - diluted	$0.53	$0.48	$1.66	$1.38

Securities_Schedule_of_Fair_Va

Securities - Schedule of Fair Value and Amortized Cost of Available-for-sale and Held-to-maturity Securities (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Investments In Debt And Marketable Equity Securities And Certain Trading Assets [Line Items]
Available-for-sale, Amortized Cost	$933,595	$1,000,505
Available-for-sale, Gross Unrealized Gains	11,179	21,363
Available-for-sale, Gross Unrealized Losses	-11,319	-624
Available-for-sale, Estimated Fair Value	933,455	1,021,244
Held-to-maturity, Amortized Cost	602,588	602,509
Held-to-maturity, Gross Unrealized Gains	17,393	37,673
Held-to-maturity, Gross Unrealized Losses	-12,766	-909
Held-to-maturity securities, Fair value	607,215	639,273
Total securities, Amortized Cost	1,536,183	1,603,014
Total securities, Gross Unrealized Gains	28,572	59,036
Total securities, Gross Unrealized Losses	-24,085	-1,533
Total securities, Estimated Fair Value	1,540,670	1,660,517
Obligations of Government Agencies [Member]
Investments In Debt And Marketable Equity Securities And Certain Trading Assets [Line Items]
Available-for-sale, Amortized Cost	71,893	96,257
Available-for-sale, Gross Unrealized Gains	20	411
Available-for-sale, Gross Unrealized Losses	-1,256	-56
Available-for-sale, Estimated Fair Value	70,657	96,612
Residential Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Agencies [Member]
Investments In Debt And Marketable Equity Securities And Certain Trading Assets [Line Items]
Available-for-sale, Amortized Cost	686,216	721,824
Available-for-sale, Gross Unrealized Gains	4,226	10,690
Available-for-sale, Gross Unrealized Losses	-9,431	-304
Available-for-sale, Estimated Fair Value	681,011	732,210
Held-to-maturity, Amortized Cost	105,907	152,872
Held-to-maturity, Gross Unrealized Gains	3,521	6,421
Held-to-maturity, Gross Unrealized Losses	-744	-80
Held-to-maturity securities, Fair value	108,684	159,213
Other Residential Collateralized Mortgage Obligations [Member]
Investments In Debt And Marketable Equity Securities And Certain Trading Assets [Line Items]
Held-to-maturity, Amortized Cost		353
Held-to-maturity, Gross Unrealized Gains		8
Held-to-maturity, Gross Unrealized Losses
Held-to-maturity securities, Fair value		361
Obligations of State and Political Subdivisions [Member]
Investments In Debt And Marketable Equity Securities And Certain Trading Assets [Line Items]
Available-for-sale, Amortized Cost	123,423	139,511
Available-for-sale, Gross Unrealized Gains	5,069	9,133
Available-for-sale, Gross Unrealized Losses	-260	-9
Available-for-sale, Estimated Fair Value	128,232	148,635
Held-to-maturity, Amortized Cost	493,968	449,284
Held-to-maturity, Gross Unrealized Gains	13,872	31,244
Held-to-maturity, Gross Unrealized Losses	-11,854	-829
Held-to-maturity securities, Fair value	495,986	479,699
Corporate Debt Securities [Member]
Investments In Debt And Marketable Equity Securities And Certain Trading Assets [Line Items]
Available-for-sale, Amortized Cost	41,819	32,706
Available-for-sale, Gross Unrealized Gains	135	213
Available-for-sale, Gross Unrealized Losses	-372	-234
Available-for-sale, Estimated Fair Value	41,582	32,685
Held-to-maturity, Amortized Cost	2,713
Held-to-maturity, Gross Unrealized Gains
Held-to-maturity, Gross Unrealized Losses	-168
Held-to-maturity securities, Fair value	2,545
Debt Securities [Member]
Investments In Debt And Marketable Equity Securities And Certain Trading Assets [Line Items]
Available-for-sale, Amortized Cost	923,351	990,298
Available-for-sale, Gross Unrealized Gains	9,450	20,447
Available-for-sale, Gross Unrealized Losses	-11,319	-603
Available-for-sale, Estimated Fair Value	921,482	1,010,142
Equity Securities [Member]
Investments In Debt And Marketable Equity Securities And Certain Trading Assets [Line Items]
Available-for-sale, Amortized Cost	10,244	10,207
Available-for-sale, Gross Unrealized Gains	1,729	916
Available-for-sale, Gross Unrealized Losses		-21
Available-for-sale, Estimated Fair Value	$11,973	$11,102

Securities_Additional_Informat

Securities - Additional Information (Detail) (USD $)	9 Months Ended		12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
	Holdings		Holdings
Amortized Cost And Fair Value Debt Securities [Abstract]
Maximum percentage of equity of one issuer	10.00%
Number of holdings greater than specified percentage of equity	0		0
Securities with aggregate par values	$703,200,000		$710,500,000
Proceed from sales - securities available-for-sale	9,265,000	48,068,000
Net unrealized security gains on the available-for-sale portfolio	-100,000		13,000,000
Gross realized security gains	300,000	1,400,000
Gross security losses	200,000
Additional Gross realized security gains	600,000	300,000
Impaired loss relating to securities	0
Federal home loan bank stock, Total	$12,000,000		$21,300,000

Securities_Schedule_of_Fair_Va1

Securities - Schedule of Fair Value of Available-for-Sale and Held-to-Maturity Securities by Contractual Maturity (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Schedule Of Available For Sale Or Held To Maturity Securities [Line Items]
Total available-for-sale securities, One Year or less	$13,463
Total available-for-sale securities, One to Five Years	79,095
Total available-for-sale securities, Five to Ten Years	81,211
Total available-for-sale securities, After Ten Years	66,702
Total available-for-sale securities, Mortgage-backed and Equity	692,984
Available-for-sale, Estimated Fair Value	933,455	1,021,244
Total held-to-maturity securities, One Year or less	3,860
Total held-to-maturity securities, One to Five Years	9,407
Total held-to-maturity securities, Five to Ten years	128,126
Total held-to-maturity securities, After Ten Years	357,138
Total held-to-maturity securities, Mortgage-backed and Equity	108,684
Held-to-maturity securities, Fair value	607,215	639,273
Total securities, One Year or less	17,323
Total securities, One to Five Years	88,502
Total securities, Five to Ten Years	209,337
Total securities, After Ten Years, Fair value	423,840
Total securities, Mortgage- backed and Equity	801,668
Total securities, Fair value	1,540,670
Obligations of Government Agencies [Member]
Schedule Of Available For Sale Or Held To Maturity Securities [Line Items]
Total available-for-sale securities, One Year or less
Total available-for-sale securities, One to Five Years	17,776
Total available-for-sale securities, Five to Ten Years	39,269
Total available-for-sale securities, After Ten Years	13,612
Total available-for-sale securities, Mortgage-backed and Equity
Available-for-sale, Estimated Fair Value	70,657	96,612
Residential Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Agencies [Member]
Schedule Of Available For Sale Or Held To Maturity Securities [Line Items]
Total available-for-sale securities, One Year or less
Total available-for-sale securities, One to Five Years
Total available-for-sale securities, Five to Ten Years
Total available-for-sale securities, After Ten Years
Total available-for-sale securities, Mortgage-backed and Equity	681,011
Available-for-sale, Estimated Fair Value	681,011	732,210
Total held-to-maturity securities, One Year or less
Total held-to-maturity securities, One to Five Years
Total held-to-maturity securities, Five to Ten years
Total held-to-maturity securities, After Ten Years
Total held-to-maturity securities, Mortgage-backed and Equity	108,684
Held-to-maturity securities, Fair value	108,684	159,213
Obligations of State and Political Subdivisions [Member]
Schedule Of Available For Sale Or Held To Maturity Securities [Line Items]
Total available-for-sale securities, One Year or less	8,388
Total available-for-sale securities, One to Five Years	45,121
Total available-for-sale securities, Five to Ten Years	26,389
Total available-for-sale securities, After Ten Years	48,334
Total available-for-sale securities, Mortgage-backed and Equity
Available-for-sale, Estimated Fair Value	128,232	148,635
Total held-to-maturity securities, One Year or less	3,860
Total held-to-maturity securities, One to Five Years	9,407
Total held-to-maturity securities, Five to Ten years	125,581
Total held-to-maturity securities, After Ten Years	357,138
Total held-to-maturity securities, Mortgage-backed and Equity
Held-to-maturity securities, Fair value	495,986	479,699
Corporate Debt Securities [Member]
Schedule Of Available For Sale Or Held To Maturity Securities [Line Items]
Total available-for-sale securities, One Year or less	5,075
Total available-for-sale securities, One to Five Years	16,198
Total available-for-sale securities, Five to Ten Years	15,553
Total available-for-sale securities, After Ten Years	4,756
Total available-for-sale securities, Mortgage-backed and Equity
Available-for-sale, Estimated Fair Value	41,582	32,685
Total held-to-maturity securities, One Year or less
Total held-to-maturity securities, One to Five Years
Total held-to-maturity securities, Five to Ten years	2,545
Total held-to-maturity securities, After Ten Years
Total held-to-maturity securities, Mortgage-backed and Equity
Held-to-maturity securities, Fair value	2,545
Equity Securities [Member]
Schedule Of Available For Sale Or Held To Maturity Securities [Line Items]
Total available-for-sale securities, One Year or less
Total available-for-sale securities, One to Five Years
Total available-for-sale securities, Five to Ten Years
Total available-for-sale securities, After Ten Years
Total available-for-sale securities, Mortgage-backed and Equity	11,973
Available-for-sale, Estimated Fair Value	$11,973	$11,102

Securities_Schedule_of_Fair_Va2

Securities - Schedule of Fair Value of Available-for-Sale and Held-to-Maturity Securities by Contractual Maturity (Parenthetical) (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Amortized Cost And Fair Value Debt Securities [Abstract]
Held-to-maturity, Amortized Cost	$602,588	$602,509

Securities_Schedule_of_Unreali

Securities - Schedule of Unrealized Losses on Investment Securities (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Security	Security
Obligations of Government Agencies [Member]
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Less than 12 months, Fair Value	$54,318	$18,894
Less than 12 months, Unrealized Losses	-1,223	-56
Less than 12 months, Number of Securities	11	6
12 months or more, Fair Value	4,549
12 months or more, Unrealized Losses	-33
12 months or more, Number of Securities	1
Fair Value, Total	58,867	18,894
Unrealized Losses, Total	-1,256	-56
Number of Securities Total	12	6
Residential Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Agencies [Member]
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Less than 12 months, Fair Value	403,983	38,913
Less than 12 months, Unrealized Losses	-10,107	-258
Less than 12 months, Number of Securities	72	20
12 months or more, Fair Value	4,515	9,966
12 months or more, Unrealized Losses	-68	-126
12 months or more, Number of Securities	6	10
Fair Value, Total	408,498	48,879
Unrealized Losses, Total	-10,175	-384
Number of Securities Total	78	30
Obligations of State and Political Subdivisions [Member]
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Less than 12 months, Fair Value	187,215	72,521
Less than 12 months, Unrealized Losses	-11,388	-838
Less than 12 months, Number of Securities	299	107
12 months or more, Fair Value	12,103
12 months or more, Unrealized Losses	-726
12 months or more, Number of Securities	13
Fair Value, Total	199,318	72,521
Unrealized Losses, Total	-12,114	-838
Number of Securities Total	312	107
Corporate Debt Securities [Member]
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Less than 12 months, Fair Value	19,943	1,526
Less than 12 months, Unrealized Losses	-452	-57
Less than 12 months, Number of Securities	7	2
12 months or more, Fair Value	2,912	10,878
12 months or more, Unrealized Losses	-88	-177
12 months or more, Number of Securities	1	5
Fair Value, Total	22,855	12,404
Unrealized Losses, Total	-540	-234
Number of Securities Total	8	7
Equity Securities [Member]
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Less than 12 months, Fair Value		2,838
Less than 12 months, Unrealized Losses		-21
Less than 12 months, Number of Securities		2
12 months or more, Fair Value
12 months or more, Unrealized Losses
12 months or more, Number of Securities
Fair Value, Total		2,838
Unrealized Losses, Total		-21
Number of Securities Total		2
Total Temporarily Impaired Securities [Member]
Schedule Of Available For Sale Securities And Held To Maturity Securities [Line Items]
Less than 12 months, Fair Value	665,459	134,692
Less than 12 months, Unrealized Losses	-23,170	-1,230
Less than 12 months, Number of Securities	389	137
12 months or more, Fair Value	24,079	20,844
12 months or more, Unrealized Losses	-915	-303
12 months or more, Number of Securities	21	15
Fair Value, Total	689,538	155,536
Unrealized Losses, Total	($24,085)	($1,533)
Number of Securities Total	410	152

Loans_and_the_Allowance_for_Cr2

Loans and the Allowance for Credit Losses - Additional Information (Detail) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
	Contract
	SecurityLoan
Financing Receivable, Recorded Investment [Line Items]
Net of deferred loan fees and costs	$2.60	$2.50
Non-accrual status period	90 days
Number of restructured contracts greater than $1 million	1
Value of restructured contracts greater than $1 million	1.5
Percentage of Total TDRs	5.30%
Accruing and non accrual TDR permitted interest only payment period	3 months
Percentage of TDRs defaulted during the period that were restructured within the last twelve months	7.40%
Loans with accruing interest	2
Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Aggregate amount of residential real estate, home equity and consumer loans classified as substandard	14.6	17.9
Internally assigned loan grades to residential real estate, home equity and consumer loans	2.2	4.9
Specific Reserves [Member]
Financing Receivable, Recorded Investment [Line Items]
Specific reserve on largest TDRs	$0.80

Loans_and_the_Allowance_for_Cr3

Loans and the Allowance for Credit Losses - Schedule of Recorded Investment in Loans by Category (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	$3,836,538	$3,687,762
Loans held for sale	6,601	21,903
Total loans	3,843,139	3,709,665
Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	217,036	193,004
Commercial Real Estate - Improved Property [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	1,650,746	1,665,341
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	1,867,782	1,858,345
Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	544,202	478,025
Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	879,703	793,702
Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	283,488	277,226
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Total portfolio loans	$261,363	$280,464

Loans_and_the_Allowance_for_Cr4

Loans and the Allowance for Credit Losses - Summary of Changes in Allowance for Credit Losses (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, beginning balance			$52,699	$54,810
Allowance for loan commitments, beginning balance			341	468
Total beginning allowance for credit losses			53,040	55,278
Provision for loan losses			5,912	16,654
Provision for loan commitments			30	-52
Total provision for credit losses	2,819	4,497	5,942	16,602
Charge-offs			-13,725	-20,955
Recoveries			2,456	2,967
Net charge-offs			-11,269	-17,988
Allowance for loan losses, ending balance	47,342	53,476	47,342	53,476
Allowance for loan commitments, ending balance	371	416	371	416
Total ending allowance for credit losses	47,713	53,892	47,713	53,892
Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, beginning balance			3,741	4,842
Allowance for loan commitments, beginning balance			27	74
Total beginning allowance for credit losses			3,768	4,916
Provision for loan losses			1,179	2,089
Provision for loan commitments			57	-11
Total provision for credit losses			1,236	2,078
Charge-offs			-526	-3,777
Recoveries			125	591
Net charge-offs			-401	-3,186
Allowance for loan losses, ending balance	4,519	3,745	4,519	3,745
Allowance for loan commitments, ending balance	84	63	84	63
Total ending allowance for credit losses	4,603	3,808	4,603	3,808
Commercial Real Estate - Improved Property [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, beginning balance			23,614	24,748
Allowance for loan commitments, beginning balance			25	21
Total beginning allowance for credit losses			23,639	24,769
Provision for loan losses			3,066	4,573
Provision for loan commitments			-1	5
Total provision for credit losses			3,065	4,578
Charge-offs			-5,651	-5,749
Recoveries			482	755
Net charge-offs			-5,169	-4,994
Allowance for loan losses, ending balance	21,511	24,327	21,511	24,327
Allowance for loan commitments, ending balance	24	26	24	26
Total ending allowance for credit losses	21,535	24,353	21,535	24,353
Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, beginning balance			9,326	11,414
Allowance for loan commitments, beginning balance			215	323
Total beginning allowance for credit losses			9,541	11,737
Provision for loan losses			-561	2,619
Provision for loan commitments			-64	-65
Total provision for credit losses			-625	2,554
Charge-offs			-1,264	-3,862
Recoveries			407	288
Net charge-offs			-857	-3,574
Allowance for loan losses, ending balance	7,908	10,459	7,908	10,459
Allowance for loan commitments, ending balance	151	258	151	258
Total ending allowance for credit losses	8,059	10,717	8,059	10,717
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, beginning balance			7,182	5,638
Allowance for loan commitments, beginning balance			6	4
Total beginning allowance for credit losses			7,188	5,642
Provision for loan losses			459	3,629
Provision for loan commitments
Total provision for credit losses			459	3,629
Charge-offs			-2,092	-3,296
Recoveries			250	288
Net charge-offs			-1,842	-3,008
Allowance for loan losses, ending balance	5,799	6,259	5,799	6,259
Allowance for loan commitments, ending balance	6	4	6	4
Total ending allowance for credit losses	5,805	6,263	5,805	6,263
Home Equity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, beginning balance			2,458	1,962
Allowance for loan commitments, beginning balance			49	33
Total beginning allowance for credit losses			2,507	1,995
Provision for loan losses			-61	1,192
Provision for loan commitments			37	12
Total provision for credit losses			-24	1,204
Charge-offs			-508	-898
Recoveries			108	17
Net charge-offs			-400	-881
Allowance for loan losses, ending balance	1,997	2,273	1,997	2,273
Allowance for loan commitments, ending balance	86	45	86	45
Total ending allowance for credit losses	2,083	2,318	2,083	2,318
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, beginning balance			5,557	5,410
Allowance for loan commitments, beginning balance			19	13
Total beginning allowance for credit losses			5,576	5,423
Provision for loan losses			1,457	2,330
Provision for loan commitments			1	7
Total provision for credit losses			1,458	2,337
Charge-offs			-3,018	-2,732
Recoveries			887	804
Net charge-offs			-2,131	-1,928
Allowance for loan losses, ending balance	4,883	5,812	4,883	5,812
Allowance for loan commitments, ending balance	20	20	20	20
Total ending allowance for credit losses	4,903	5,832	4,903	5,832
Deposit Overdraft [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses, beginning balance			821	796
Allowance for loan commitments, beginning balance
Total beginning allowance for credit losses			821	796
Provision for loan losses			373	222
Provision for loan commitments
Total provision for credit losses			373	222
Charge-offs			-666	-641
Recoveries			197	224
Net charge-offs			-469	-417
Allowance for loan losses, ending balance	725	601	725	601
Allowance for loan commitments, ending balance
Total ending allowance for credit losses	$725	$601	$725	$601

Loans_and_the_Allowance_for_Cr5

Loans and the Allowance for Credit Losses - Allowance for Credit Losses and Recorded Investments in Loans (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loans individually evaluated for impairment	$1,313	$1,743
Allowance for loans collectively evaluated for impairment	46,029	50,956
Allowance for loan commitments	371	341	416	468
Total allowance for credit losses	47,713	53,040	53,892	55,278
Individually evaluated for impairment	4,957	9,532
Collectively evaluated for impairment	3,831,581	3,678,230
Total Loans	3,836,538	3,687,762
Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loans individually evaluated for impairment	849	832
Allowance for loans collectively evaluated for impairment	3,670	2,909
Allowance for loan commitments	84	27	63	74
Total allowance for credit losses	4,603	3,768	3,808	4,916
Individually evaluated for impairment	1,948	2,545
Collectively evaluated for impairment	215,088	190,459
Total Loans	217,036	193,004
Commercial Real Estate - Improved Property [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loans individually evaluated for impairment	464	911
Allowance for loans collectively evaluated for impairment	21,047	22,703
Allowance for loan commitments	24	25	26	21
Total allowance for credit losses	21,535	23,639	24,353	24,769
Individually evaluated for impairment	2,801	6,987
Collectively evaluated for impairment	1,647,945	1,658,354
Total Loans	1,650,746	1,665,341
Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loans individually evaluated for impairment
Allowance for loans collectively evaluated for impairment	7,908	9,326
Allowance for loan commitments	151	215	258	323
Total allowance for credit losses	8,059	9,541	10,717	11,737
Individually evaluated for impairment	208
Collectively evaluated for impairment	543,994	478,025
Total Loans	544,202	478,025
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loans individually evaluated for impairment
Allowance for loans collectively evaluated for impairment	5,799	7,182
Allowance for loan commitments	6	6	4	4
Total allowance for credit losses	5,805	7,188	6,263	5,642
Individually evaluated for impairment
Collectively evaluated for impairment	879,703	793,702
Total Loans	879,703	793,702
Home Equity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loans individually evaluated for impairment
Allowance for loans collectively evaluated for impairment	1,997	2,458
Allowance for loan commitments	86	49	45	33
Total allowance for credit losses	2,083	2,507	2,318	1,995
Individually evaluated for impairment
Collectively evaluated for impairment	283,488	277,226
Total Loans	283,488	277,226
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loans individually evaluated for impairment
Allowance for loans collectively evaluated for impairment	4,883	5,557
Allowance for loan commitments	20	19	20	13
Total allowance for credit losses	4,903	5,576	5,832	5,423
Individually evaluated for impairment
Collectively evaluated for impairment	261,363	280,464
Total Loans	261,363	280,464
Deposit Overdraft [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loans individually evaluated for impairment
Allowance for loans collectively evaluated for impairment	725	821
Allowance for loan commitments
Total allowance for credit losses	725	821	601	796
Individually evaluated for impairment
Collectively evaluated for impairment
Total Loans

Loans_and_the_Allowance_for_Cr6

Loans and the Allowance for Credit Losses - Allowance for Credit Losses and Recorded Investments in Loans (Parenthetical) (Detail) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013
Receivables [Abstract]
Trouble debt restructuring threshold	$1

Loans_and_the_Allowance_for_Cr7

Loans and the Allowance for Credit Losses - Summary of Commercial Loans by Risk Grade (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Summary of commercial loans by risk grade
Commercial loans	$2,411,984	$2,336,370
Excellent - Minimal Risk [Member]
Summary of commercial loans by risk grade
Commercial loans	74,390	65,044
Good - Desirable Risk [Member]
Summary of commercial loans by risk grade
Commercial loans	932,890	892,592
Fair - Acceptable Risk [Member]
Summary of commercial loans by risk grade
Commercial loans	1,263,405	1,205,997
Criticized - Marginal [Member]
Summary of commercial loans by risk grade
Commercial loans	76,442	86,777
Classified - Substandard [Member]
Summary of commercial loans by risk grade
Commercial loans	64,857	85,960
Classified - Doubtful [Member]
Summary of commercial loans by risk grade
Commercial loans
Commercial Real Estate - Land and Construction [Member]
Summary of commercial loans by risk grade
Commercial loans	217,036	193,004
Commercial Real Estate - Land and Construction [Member] | Excellent - Minimal Risk [Member]
Summary of commercial loans by risk grade
Commercial loans
Commercial Real Estate - Land and Construction [Member] | Good - Desirable Risk [Member]
Summary of commercial loans by risk grade
Commercial loans	32,271	38,292
Commercial Real Estate - Land and Construction [Member] | Fair - Acceptable Risk [Member]
Summary of commercial loans by risk grade
Commercial loans	172,558	136,643
Commercial Real Estate - Land and Construction [Member] | Criticized - Marginal [Member]
Summary of commercial loans by risk grade
Commercial loans	6,859	10,573
Commercial Real Estate - Land and Construction [Member] | Classified - Substandard [Member]
Summary of commercial loans by risk grade
Commercial loans	5,348	7,496
Commercial Real Estate - Land and Construction [Member] | Classified - Doubtful [Member]
Summary of commercial loans by risk grade
Commercial loans
Commercial Real Estate - Improved Property [Member]
Summary of commercial loans by risk grade
Commercial loans	1,650,746	1,665,341
Commercial Real Estate - Improved Property [Member] | Excellent - Minimal Risk [Member]
Summary of commercial loans by risk grade
Commercial loans	684	789
Commercial Real Estate - Improved Property [Member] | Good - Desirable Risk [Member]
Summary of commercial loans by risk grade
Commercial loans	716,005	701,447
Commercial Real Estate - Improved Property [Member] | Fair - Acceptable Risk [Member]
Summary of commercial loans by risk grade
Commercial loans	827,814	826,790
Commercial Real Estate - Improved Property [Member] | Criticized - Marginal [Member]
Summary of commercial loans by risk grade
Commercial loans	55,445	66,906
Commercial Real Estate - Improved Property [Member] | Classified - Substandard [Member]
Summary of commercial loans by risk grade
Commercial loans	50,798	69,409
Commercial Real Estate - Improved Property [Member] | Classified - Doubtful [Member]
Summary of commercial loans by risk grade
Commercial loans
Commercial and Industrial [Member]
Summary of commercial loans by risk grade
Commercial loans	544,202	478,025
Commercial and Industrial [Member] | Excellent - Minimal Risk [Member]
Summary of commercial loans by risk grade
Commercial loans	73,706	64,255
Commercial and Industrial [Member] | Good - Desirable Risk [Member]
Summary of commercial loans by risk grade
Commercial loans	184,614	152,853
Commercial and Industrial [Member] | Fair - Acceptable Risk [Member]
Summary of commercial loans by risk grade
Commercial loans	263,033	242,564
Commercial and Industrial [Member] | Criticized - Marginal [Member]
Summary of commercial loans by risk grade
Commercial loans	14,138	9,298
Commercial and Industrial [Member] | Classified - Substandard [Member]
Summary of commercial loans by risk grade
Commercial loans	8,711	9,055
Commercial and Industrial [Member] | Classified - Doubtful [Member]
Summary of commercial loans by risk grade
Commercial loans

Loans_and_the_Allowance_for_Cr8

Loans and the Allowance for Credit Losses - Summary of Age Analysis of Loan Categories (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment [Line Items]
Current	$3,789,099	$3,629,661
30-59 Days Past Due	8,932	17,713
60-89 Days Past Due	9,184	8,789
90 Days or More Past Due	29,323	31,599
Total Past Due	47,439	58,101
Total Loans	3,836,538	3,687,762
Loans held for sale	6,601	21,903
90 Days or More Past Due and Accruing	3,043	5,294
Total loans, current	3,795,700	3,651,564
Total loans	3,843,139	3,709,665
Loans Held for Sale [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans held for sale, current	6,601	21,903
30-59 Days Past Due
60-89 Days Past Due
90 Days or More Past Due
Total Past Due
Loans held for sale	6,601	21,903
90 Days or More Past Due and Accruing
Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	213,429	189,072
30-59 Days Past Due	38	1,470
60-89 Days Past Due
90 Days or More Past Due	3,569	2,462
Total Past Due	3,607	3,932
Total Loans	217,036	193,004
90 Days or More Past Due and Accruing	248
Commercial Real Estate - Improved Property [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	1,633,805	1,643,833
30-59 Days Past Due	2,211	5,722
60-89 Days Past Due	2,850	2,224
90 Days or More Past Due	11,880	13,562
Total Past Due	16,941	21,508
Total Loans	1,650,746	1,665,341
90 Days or More Past Due and Accruing	541	338
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	1,847,234	1,832,905
30-59 Days Past Due	2,249	7,192
60-89 Days Past Due	2,850	2,224
90 Days or More Past Due	15,449	16,024
Total Past Due	20,548	25,440
Total Loans	1,867,782	1,858,345
90 Days or More Past Due and Accruing	789	338
Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	539,917	475,186
30-59 Days Past Due	435	283
60-89 Days Past Due	1,801	412
90 Days or More Past Due	2,049	2,144
Total Past Due	4,285	2,839
Total Loans	544,202	478,025
90 Days or More Past Due and Accruing	68	98
Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	864,580	774,006
30-59 Days Past Due	1,799	4,231
60-89 Days Past Due	3,606	4,833
90 Days or More Past Due	9,718	10,632
Total Past Due	15,123	19,696
Total Loans	879,703	793,702
90 Days or More Past Due and Accruing	1,601	3,199
Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	279,803	274,235
30-59 Days Past Due	1,579	1,352
60-89 Days Past Due	491	197
90 Days or More Past Due	1,615	1,442
Total Past Due	3,685	2,991
Total Loans	283,488	277,226
90 Days or More Past Due and Accruing	307	722
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	257,565	273,329
30-59 Days Past Due	2,870	4,655
60-89 Days Past Due	436	1,123
90 Days or More Past Due	492	1,357
Total Past Due	3,798	7,135
Total Loans	261,363	280,464
90 Days or More Past Due and Accruing	278	937
Non-Accrual Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	10,493	11,724
30-59 Days Past Due	1,175	591
60-89 Days Past Due	655	1,747
90 Days or More Past Due	25,837	25,310
Total Past Due	27,667	27,648
Total Loans	38,160	39,372
TDRs Accruing Interest [Member]
Financing Receivable, Recorded Investment [Line Items]
Current	14,362	21,665
30-59 Days Past Due	85	794
60-89 Days Past Due	590	827
90 Days or More Past Due	443	995
Total Past Due	1,118	2,616
Total Loans	$15,480	$24,281

Loans_and_the_Allowance_for_Cr9

Loans and the Allowance for Credit Losses - Summary of Age Analysis of Loan Categories (Parenthetical) (Detail)	9 Months Ended
	Sep. 30, 2013
Receivables [Abstract]
Past due loans excluded TDRs past due and accruing	90 days

Recovered_Sheet1

Loans and the Allowance for Credit Losses - Summary of Impaired Loans (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Schedule Of Financial Receivables [Line Items]
Unpaid Principal Balance	$58,565		$58,565		$73,404
Recorded Investment	53,640		53,640		63,653
Related Allowance	1,313		1,313		1,743
Average Recorded Investment	57,992	63,634	60,696	73,787
Interest Income Recognized	389	371	1,321	1,201
Impaired Loans with No Related Specific Allowance Recorded [Member]
Schedule Of Financial Receivables [Line Items]
Unpaid Principal Balance	56,417		56,417		67,679
Recorded Investment	51,492		51,492		58,044
Related Allowance
Average Recorded Investment	53,727	53,383	55,902	62,344
Interest Income Recognized	383	286	1,293	936
Impaired Loans with No Related Specific Allowance Recorded [Member] | Commercial Real Estate - Land and Construction [Member]
Schedule Of Financial Receivables [Line Items]
Unpaid Principal Balance	3,312		3,312		9,278
Recorded Investment	3,212		3,212		5,577
Related Allowance
Average Recorded Investment	4,181	7,865	5,049	9,923
Interest Income Recognized		21	89	193
Impaired Loans with No Related Specific Allowance Recorded [Member] | Commercial Real Estate - Improved Property [Member]
Schedule Of Financial Receivables [Line Items]
Unpaid Principal Balance	22,643		22,643		27,515
Recorded Investment	20,572		20,572		24,455
Related Allowance
Average Recorded Investment	22,777	25,636	23,471	29,503
Interest Income Recognized	92	160	408	442
Impaired Loans with No Related Specific Allowance Recorded [Member] | Commercial and Industrial [Member]
Schedule Of Financial Receivables [Line Items]
Unpaid Principal Balance	4,145		4,145		4,546
Recorded Investment	3,569		3,569		4,019
Related Allowance
Average Recorded Investment	3,643	5,683	3,884	7,005
Interest Income Recognized	26	37	87	96
Impaired Loans with No Related Specific Allowance Recorded [Member] | Residential Real Estate [Member]
Schedule Of Financial Receivables [Line Items]
Unpaid Principal Balance	22,000		22,000		22,146
Recorded Investment	20,294		20,294		20,269
Related Allowance
Average Recorded Investment	19,487	13,022	19,872	14,588
Interest Income Recognized	217	64	582	198
Impaired Loans with No Related Specific Allowance Recorded [Member] | Home Equity [Member]
Schedule Of Financial Receivables [Line Items]
Unpaid Principal Balance	2,764		2,764		2,437
Recorded Investment	2,527		2,527		2,207
Related Allowance
Average Recorded Investment	2,278	1,008	2,201	1,104
Interest Income Recognized	20	4	50	6
Impaired Loans with No Related Specific Allowance Recorded [Member] | Consumer [Member]
Schedule Of Financial Receivables [Line Items]
Unpaid Principal Balance	1,553		1,553		1,757
Recorded Investment	1,318		1,318		1,517
Related Allowance
Average Recorded Investment	1,361	169	1,425	221
Interest Income Recognized	28		77	1
Impaired Loans with a Specific Allowance Recorded [Member]
Schedule Of Financial Receivables [Line Items]
Unpaid Principal Balance	2,148		2,148		5,725
Recorded Investment	2,148		2,148		5,609
Related Allowance	1,313		1,313		1,743
Average Recorded Investment	4,265	10,251	4,794	11,443
Interest Income Recognized	6	85	28	265
Impaired Loans with a Specific Allowance Recorded [Member] | Commercial Real Estate - Land and Construction [Member]
Schedule Of Financial Receivables [Line Items]
Unpaid Principal Balance	1,463		1,463		1,627
Recorded Investment	1,463		1,463		1,627
Related Allowance	849		849		832
Average Recorded Investment	1,500	2,211	1,543	3,204
Interest Income Recognized	6	40	28	40
Impaired Loans with a Specific Allowance Recorded [Member] | Commercial Real Estate - Improved Property [Member]
Schedule Of Financial Receivables [Line Items]
Unpaid Principal Balance	685		685		4,098
Recorded Investment	685		685		3,982
Related Allowance	464		464		911
Average Recorded Investment	2,765	8,040	3,251	8,239
Interest Income Recognized		$45		$225

Recovered_Sheet2

Loans and the Allowance for Credit Losses - Recorded Investment in Non-Accrual Loans and TDRs (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Schedule Of Financial Receivables [Line Items]
Non-accrual loans	$38,160	$39,372
TDRs	28,400	39,282
Accruing TDRs [Member]
Schedule Of Financial Receivables [Line Items]
TDRs	15,480	24,281
Non Accrual TDRs [Member]
Schedule Of Financial Receivables [Line Items]
TDRs	12,920	15,001
Commercial Real Estate - Land and Construction [Member]
Schedule Of Financial Receivables [Line Items]
Non-accrual loans	4,675	4,668
TDRs	4,056	5,472
Commercial Real Estate - Land and Construction [Member] | Accruing TDRs [Member]
Schedule Of Financial Receivables [Line Items]
TDRs		2,537
Commercial Real Estate - Land and Construction [Member] | Non Accrual TDRs [Member]
Schedule Of Financial Receivables [Line Items]
TDRs	4,056	2,935
Commercial Real Estate - Improved Property [Member]
Schedule Of Financial Receivables [Line Items]
Non-accrual loans	18,105	18,239
TDRs	7,702	16,650
Commercial Real Estate - Improved Property [Member] | Accruing TDRs [Member]
Schedule Of Financial Receivables [Line Items]
TDRs	3,152	10,198
Commercial Real Estate - Improved Property [Member] | Non Accrual TDRs [Member]
Schedule Of Financial Receivables [Line Items]
TDRs	4,550	6,452
Commercial Real Estate [Member]
Schedule Of Financial Receivables [Line Items]
Non-accrual loans	22,780	22,907
TDRs	11,758	22,122
Commercial Real Estate [Member] | Accruing TDRs [Member]
Schedule Of Financial Receivables [Line Items]
TDRs	3,152	12,735
Commercial Real Estate [Member] | Non Accrual TDRs [Member]
Schedule Of Financial Receivables [Line Items]
TDRs	8,606	9,387
Commercial and Industrial [Member]
Schedule Of Financial Receivables [Line Items]
Non-accrual loans	3,014	3,387
TDRs	973	1,360
Commercial and Industrial [Member] | Accruing TDRs [Member]
Schedule Of Financial Receivables [Line Items]
TDRs	555	632
Commercial and Industrial [Member] | Non Accrual TDRs [Member]
Schedule Of Financial Receivables [Line Items]
TDRs	418	728
Residential Real Estate [Member]
Schedule Of Financial Receivables [Line Items]
Non-accrual loans	10,085	11,247
TDRs	13,399	13,099
Residential Real Estate [Member] | Accruing TDRs [Member]
Schedule Of Financial Receivables [Line Items]
TDRs	10,209	9,022
Residential Real Estate [Member] | Non Accrual TDRs [Member]
Schedule Of Financial Receivables [Line Items]
TDRs	3,190	4,077
Home Equity [Member]
Schedule Of Financial Receivables [Line Items]
Non-accrual loans	1,636	1,184
TDRs	1,275	1,541
Home Equity [Member] | Accruing TDRs [Member]
Schedule Of Financial Receivables [Line Items]
TDRs	891	1,022
Home Equity [Member] | Non Accrual TDRs [Member]
Schedule Of Financial Receivables [Line Items]
TDRs	384	519
Consumer [Member]
Schedule Of Financial Receivables [Line Items]
Non-accrual loans	645	647
TDRs	995	1,160
Consumer [Member] | Accruing TDRs [Member]
Schedule Of Financial Receivables [Line Items]
TDRs	673	870
Consumer [Member] | Non Accrual TDRs [Member]
Schedule Of Financial Receivables [Line Items]
TDRs	$322	$290

Recovered_Sheet3

Loans and the Allowance for Credit Losses - Loans Identified as TDRs (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
	Contract	Contract	Contract	Contract
Financing Receivable, Modifications [Line Items]
Number of Modifications	22	2	55	19
Pre-Modification Outstanding Recorded Investment	$609	$1,396	$3,512	$4,180
Post-Modification Outstanding Recorded Investment	552	1,240	3,193	3,611
Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Modifications [Line Items]
Number of Modifications	1		2	1
Pre-Modification Outstanding Recorded Investment	66		366	516
Post-Modification Outstanding Recorded Investment	65		359	516
Commercial Real Estate - Improved Property [Member]
Financing Receivable, Modifications [Line Items]
Number of Modifications	1	1	6	9
Pre-Modification Outstanding Recorded Investment	49	1,073	568	2,741
Post-Modification Outstanding Recorded Investment	49	917	395	2,162
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Modifications	2	1	8	10
Pre-Modification Outstanding Recorded Investment	115	1,073	934	3,257
Post-Modification Outstanding Recorded Investment	114	917	754	2,678
Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Modifications	1		7	2
Pre-Modification Outstanding Recorded Investment	14		164	40
Post-Modification Outstanding Recorded Investment	14		161	37
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Modifications	8	1	24	7
Pre-Modification Outstanding Recorded Investment	307	323	2,180	883
Post-Modification Outstanding Recorded Investment	280	323	2,094	896
Home Equity [Member]
Financing Receivable, Modifications [Line Items]
Number of Modifications	2		3
Pre-Modification Outstanding Recorded Investment	75		91
Post-Modification Outstanding Recorded Investment	52		64
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Modifications	9		13
Pre-Modification Outstanding Recorded Investment	98		143
Post-Modification Outstanding Recorded Investment	$92		$120

Recovered_Sheet4

Loans and the Allowance for Credit Losses - TDRs Defaulted Later Restructured (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
	Defaults	Defaults	Defaults	Defaults
Financing Receivable, Modifications [Line Items]
Number of Defaults	12	1	35	10
Recorded Investment	$508	$45	$2,106	$2,229
Commercial Real Estate - Land and Construction [Member]
Financing Receivable, Modifications [Line Items]
Number of Defaults
Recorded Investment
Commercial Real Estate - Improved Property [Member]
Financing Receivable, Modifications [Line Items]
Number of Defaults			1	8
Recorded Investment			45	2,018
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Defaults			1	8
Recorded Investment			45	2,018
Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Defaults		1	2	2
Recorded Investment		45	293	211
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Defaults	8		24
Recorded Investment	451		1,624
Home Equity [Member]
Financing Receivable, Modifications [Line Items]
Number of Defaults	1		5
Recorded Investment	20		107
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Defaults	3		3
Recorded Investment	$37		$37

Recovered_Sheet5

Loans and the Allowance for Credit Losses - Summary of Other Real Estate Owned and Repossessed Assets (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Receivables [Abstract]
Other real estate owned	$4,871	$5,741
Repossessed assets	313	247
Total other real estate owned and repossessed assets	$5,184	$5,988

Federal_Home_Loan_Bank_Borrowi2

Federal Home Loan Bank Borrowings - Additional Information (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Banking And Thrift [Abstract]
Borrowings	$59,918,000	$111,200,000
Weighted-average rate, Total	2.72%	3.04%
FHLB stock owned by WesBanco pledged as collateral on these advances	12,000,000	21,300,000
Remaining maximum borrowing capacity	1,500,000,000	1,300,000,000
Outstanding in FHLB convertible advances subject to call or conversion	$6,000,000

Federal_Home_Loan_Bank_Borrowi3

Federal Home Loan Bank Borrowings - Aggregate Annual Maturities and Weighted-Average Interest Rates of Federal Home Loan Bank (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Banking And Thrift [Abstract]
Scheduled Maturity, 2013	$20,144
Scheduled Maturity, 2014	16,038
Scheduled Maturity, 2015	888
Scheduled Maturity, 2016	83
Scheduled maturity, 2017	15,641
Scheduled Maturity, 2018 and thereafter	7,124
Scheduled Maturity, Total	$59,918	$111,200
Weighted Average Rate, 2013	0.55%
Weighted Average Rate, 2014	3.40%
Weighted Average Rate, 2015	4.69%
Weighted Average Rate, 2016	4.35%
Weighted Average Rate, 2017	3.77%
Weighted Average Rate, 2018 and thereafter	4.75%
Weighted Average Rate, Total	2.72%	3.04%

Pension_Plan_Components_of_Net

Pension Plan - Components of Net Periodic Pension Cost (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Compensation And Retirement Disclosure [Abstract]
Service cost - benefits earned during year	$742	$688	$2,398	$2,049
Interest cost on projected benefit obligation	1,015	976	3,092	2,907
Expected return on plan assets	-1,485	-1,393	-4,525	-4,149
Amortization of prior service cost	11	11	34	34
Amortization of net loss	906	575	2,626	1,712
Net periodic pension cost	$1,189	$857	$3,625	$2,553

Pension_Plan_Additional_Inform

Pension Plan - Additional Information (Detail) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013
Compensation And Retirement Disclosure [Abstract]
Minimum required pension plan contribution	$3.70
Partial credit balance utilized for minimum required contribution	23.6
Contribution of Pension Fund	2.5
Additional expected Contribution of pension fund	$2.50

Fair_Value_Measurement_Schedul

Fair Value Measurement - Schedule of Fair Value of Assets and Liabilities Measured on Recurring and Nonrecurring Basis (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	$933,455	$1,021,244
Loans held for sale	6,601	21,903
Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	933,455	1,021,244
Total recurring fair value measurements	933,455	1,021,244
Nonrecurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans	835	3,866
Other real estate owned and repossessed assets	5,184	5,988
Mortgage servicing rights	897	825
Loans held for sale	6,601	21,903
Total nonrecurring fair value measurements	13,517	32,582
Obligations of Government Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	70,657	96,612
Obligations of Government 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	70,657	96,612
Residential Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	681,011	732,210
Residential Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government 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	681,011	732,210
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	128,232	148,635
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	128,232	148,635
Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	41,582	32,685
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	41,582	32,685
Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	11,973	11,102
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	11,973	11,102
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale	9,443	9,059
Loans held for sale
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]
Total securities - available-for-sale	9,443	9,059
Total recurring fair value measurements	9,443	9,059
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Nonrecurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans
Other real estate owned and repossessed assets
Mortgage servicing rights
Loans held for sale
Total nonrecurring fair value measurements
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Obligations of Government 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
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Residential Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government 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
Quoted Prices in Active Markets for Identical Assets (Level 1) [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
Quoted Prices in Active Markets for Identical Assets (Level 1) [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
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	9,443	9,059
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	924,012	1,012,162
Loans held for sale	6,601	21,903
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	924,012	1,012,162
Total recurring fair value measurements	924,012	1,012,162
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]
Impaired loans
Other real estate owned and repossessed assets
Mortgage servicing rights
Loans held for sale	6,601	21,903
Total nonrecurring fair value measurements	6,601	21,903
Significant Other Observable Inputs (Level 2) [Member] | Obligations of Government 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	70,657	96,612
Significant Other Observable Inputs (Level 2) [Member] | Residential Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government 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	681,011	732,210
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	128,232	148,612
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	41,582	32,685
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	2,530	2,043
Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale		23
Loans held for sale
Significant Unobservable Inputs (Level 3) [Member] | Recurring Fair Value Measurements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total securities - available-for-sale		23
Total recurring fair value measurements		23
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	835	3,866
Other real estate owned and repossessed assets	5,184	5,988
Mortgage servicing rights	897	825
Loans held for sale
Total nonrecurring fair value measurements	6,916	10,679
Significant Unobservable Inputs (Level 3) [Member] | Obligations of Government 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
Significant Unobservable Inputs (Level 3) [Member] | Residential Mortgage-Backed Securities and Collateralized Mortgage Obligations of Government 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
Significant Unobservable Inputs (Level 3) [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		23
Significant Unobservable Inputs (Level 3) [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
Significant Unobservable Inputs (Level 3) [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

Fair_Value_Measurement_Schedul1

Fair Value Measurement - Schedule of Assets Measured at Fair Value on Nonrecurring Basis (Detail) (USD $)	9 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Nonrecurring Fair Value Measurements [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Impaired loans	835	3,866
Mortgage servicing rights	897	825
Significant Unobservable Inputs (Level 3) [Member] | Nonrecurring Fair Value Measurements [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Impaired loans	835	3,866
Other real estate owned and repossessed assets	5,184	5,988
Mortgage servicing rights	897	825
Significant Unobservable Inputs (Level 3) [Member] | Minimum [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Weighted Average, Appraisal adjustments	0.00%	0.00%
Impaired loans liquidation expenses	0.00%	-3.90%
Significant Unobservable Inputs (Level 3) [Member] | Minimum [Member] | Discounted Cash Flow [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Discount rate	9.00%	9.00%
Remaining term of mortgage	2 years 7 months 6 days	2 years 9 months 18 days
Significant Unobservable Inputs (Level 3) [Member] | Maximum [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Weighted Average, Appraisal adjustments	-43.40%	-50.80%
Impaired loans liquidation expenses	-8.00%	-8.00%
Significant Unobservable Inputs (Level 3) [Member] | Maximum [Member] | Discounted Cash Flow [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Discount rate	12.00%	12.00%
Remaining term of mortgage	26 years	27 years
Significant Unobservable Inputs (Level 3) [Member] | Weighted Average [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Discount rate	9.80%	9.80%
Weighted Average, Appraisal adjustments	-15.40%	-13.70%
Impaired loans liquidation expenses	-5.00%	-6.80%
Significant Unobservable Inputs (Level 3) [Member] | Weighted Average [Member] | Discounted Cash Flow [Member]
Fair Value Of Assets And Liabilities Measured On Non Recurring Basis [Line Items]
Weighted average remaining term	15 years 1 month 6 days	15 years 9 months 18 days

Fair_Value_Measurement_Estimat

Fair Value Measurement - Estimates Fair Value of Financial Instruments (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Financial Assets
Cash and due from banks	$145,639	$125,605	$116,411	$140,325
Securities available-for-sale	933,455	1,021,244
Securities held-to-maturity	602,588	602,509
Net loans	3,789,196	3,635,063
Loans held for sale	6,601	21,903
Accrued interest receivable	19,903	19,354
Bank owned life insurance	120,457	119,671
Financial Liabilities
Deposits	5,060,442	4,944,284
Federal Home Loan Bank borrowings	59,918	111,187
Other borrowings	124,179	142,971
Junior subordinated debt	106,127	113,832
Accrued interest payable	3,535	3,856
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial Assets
Cash and due from banks	145,639	125,605
Securities available-for-sale	9,443	9,059
Securities held-to-maturity
Net loans
Loans held for sale
Accrued interest receivable	19,903	19,354
Bank owned life insurance	120,457	119,671
Financial Liabilities
Deposits	3,421,995	3,294,664
Federal Home Loan Bank borrowings
Other borrowings	77,746	95,768
Junior subordinated debt
Accrued interest payable	3,535	3,856
Significant Other Observable Inputs (Level 2) [Member]
Financial Assets
Cash and due from banks
Securities available-for-sale	924,012	1,012,162
Securities held-to-maturity	606,462	638,469
Net loans
Loans held for sale	6,601	21,903
Accrued interest receivable
Bank owned life insurance
Financial Liabilities
Deposits	1,653,561	1,668,692
Federal Home Loan Bank borrowings	63,338	114,461
Other borrowings	49,227	46,985
Junior subordinated debt	66,390	64,624
Accrued interest payable
Significant Unobservable Inputs (Level 3) [Member]
Financial Assets
Cash and due from banks
Securities available-for-sale		23
Securities held-to-maturity	753	804
Net loans	3,720,889	3,600,068
Loans held for sale
Accrued interest receivable
Bank owned life insurance
Financial Liabilities
Deposits
Federal Home Loan Bank borrowings
Other borrowings
Junior subordinated debt
Accrued interest payable
Carrying Amount [Member]
Financial Assets
Cash and due from banks	145,639	125,605
Securities available-for-sale	933,455	1,021,244
Securities held-to-maturity	602,588	602,509
Net loans	3,789,196	3,635,063
Loans held for sale	6,601	21,903
Accrued interest receivable	19,903	19,354
Bank owned life insurance	120,457	119,671
Financial Liabilities
Deposits	5,060,442	4,944,284
Federal Home Loan Bank borrowings	59,918	111,187
Other borrowings	124,179	142,971
Junior subordinated debt	106,127	113,832
Accrued interest payable	3,535	3,856
Fair Value Estimate [Member]
Financial Assets
Cash and due from banks	145,639	125,605
Securities available-for-sale	933,455	1,021,244
Securities held-to-maturity	607,215	639,273
Net loans	3,720,889	3,600,068
Loans held for sale	6,601	21,903
Accrued interest receivable	19,903	19,354
Bank owned life insurance	120,457	119,671
Financial Liabilities
Deposits	5,075,556	4,963,356
Federal Home Loan Bank borrowings	63,338	114,461
Other borrowings	126,973	142,753
Junior subordinated debt	66,390	64,624
Accrued interest payable	$3,535	$3,856

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Income - Components of Accumulated Other Comprehensive Income (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Equity [Abstract]
Beginning Balance, Defined Benefit Pension Plan			($21,401)	($15,155)
Defined Benefit Pension Plan, Other comprehensive income before reclassifications
Defined Benefit Pension Plan, Amounts reclassified from accumulated other comprehensive income	580	370	1,630	1,044
Defined Benefit Pension Plan, Period change			1,630	1,044
Ending Balance, Defined Benefit Pension Plan	-19,771	-14,111	-19,771	-14,111
Beginning balance, Unrealized Gains (Losses) on Securities Available-for-Sale			13,032	11,292
Unrealized Gains (Losses) on Securities Available-for-Sale, Other comprehensive income before reclassifications			-13,095	2,506
Unrealized Gains (Losses) on Securities Available-for-Sale, Amounts reclassified from accumulated other comprehensive income	6	-202	-75	-884
Unrealized Gains (Losses) on Securities Available-for-Sale, Period change			-13,170	1,622
Ending Balance, Unrealized Gains (Losses) on Securities Available-for-Sale	-138	12,914	-138	12,914
Beginning balance, Unrealized Gains on Securities Transferred from Available-for-Sale to Held-to-Maturity			2,004	2,961
Unrealized Gains (Losses) on Securities Transferred from Available-for-Sale to Held-to-maturity, Other comprehensive income before reclassifications
Unrealized Gains on Securities Transferred from Available-for-Sale to Held-to-Maturity, Amounts reclassified from accumulated other comprehensive income	-131	-233	-537	-745
Unrealized Gains on Securities Transferred from Available-for-Sale to Held-to-Maturity, Period change			-537	-745
Ending Balance, Unrealized Gains on Securities Transferred from Available-for-Sale to Held-to-Maturity	1,467	2,216	1,467	2,216
Beginning Balance, Accumulated Other Comprehensive Income			-6,365	-902
Other comprehensive income before reclassifications			-13,095	2,506
Amounts reclassified from accumulated other comprehensive income	455	-65	1,018	-585
Other comprehensive income			-12,077	1,921
Ending Balance, Accumulated Other Comprehensive Income	($18,442)	$1,019	($18,442)	$1,019

Accumulated_Other_Comprehensiv3

Accumulated Other Comprehensive Income - Components of Accumulated Other Comprehensive Income (Parenthetical) (Detail)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Equity [Abstract]
Percentage of Federal and State income tax rate	37.00%	37.00%

Accumulated_Other_Comprehensiv4

Accumulated Other Comprehensive Income - Schedule of Accumulated Other Comprehensive Income Component Details (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Securities available-for-sale:
Net securities losses/(gains) reclassified into earnings	$10	($322)	($119)	($1,407)
Related income tax (benefit)/expense	-4	120	44	523
Net effect on accumulated other comprehensive income for the period	6	-202	-75	-884
Securities held-to-maturity:
Amortization of unrealized gain transferred from available-for-sale	-207	-369	-857	-1,199
Related income tax expense	76	136	320	454
Net effect on accumulated other comprehensive income for the period	-131	-233	-537	-745
Defined benefit pension plan:
Amortization of net loss and prior service costs	918	588	2,661	1,748
Related income tax expense	-338	-218	-1,031	-704
Net effect on accumulated other comprehensive income for the period	580	370	1,630	1,044
Total reclassifications for the period	$455	($65)	$1,018	($585)

Commitments_and_Contingent_Lia2

Commitments and Contingent Liabilities - Additional Information (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Commitments And Contingencies Disclosure [Abstract]
Allowance for credit losses associated with loan commitments	$0.40	$0.30

Commitments_and_Contingent_Lia3

Commitments and Contingent Liabilities - Commitments to Extend Credit, Guarantees and Various Letters of Credit Outstanding (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Commitments And Contingencies Disclosure [Abstract]
Lines of credit	$913,457	$769,525
Loans approved but not closed	201,838	218,531
Overdraft limits	88,025	93,654
Letters of credit	18,922	20,078
Contingent obligations to purchase loans funded by other entities	$6,332	$6,668

Business_Segments_Additional_I

Business Segments - Additional Information (Detail) (USD $)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2012
	Segment	Trust and Investment Services [Member]	Trust and Investment Services [Member]
Segment Reporting Information [Line Items]
Operating segments	2
Market value of assets held by trust and investment services segment		$3,500,000,000	$3,200,000,000
Total non-fiduciary assets		$3,300,000	$2,800,000

Business_Segments_Financial_In

Business Segments - Financial Information by Business Segment (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Segment Reporting Information [Line Items]
Interest income	$54,317	$52,288	$163,634	$158,514
Interest expense	8,186	10,594	25,385	33,450
Net interest income	46,131	41,694	138,249	125,064
Provision for credit losses	2,819	4,497	5,942	16,602
Net interest income after provision for credit losses	43,312	37,197	132,307	108,462
Non-interest income	17,116	15,962	52,336	47,178
Non-interest expense	40,009	36,790	120,256	108,538
Income before provision for income taxes	20,419	16,369	64,387	47,102
Provision for income taxes	4,884	3,463	15,815	10,208
Net income	15,535	12,906	48,572	36,894
Community Banking [Member]
Segment Reporting Information [Line Items]
Interest income	54,317	52,288	163,634	158,514
Interest expense	8,186	10,594	25,385	33,450
Net interest income	46,131	41,694	138,249	125,064
Provision for credit losses	2,819	4,497	5,942	16,602
Net interest income after provision for credit losses	43,312	37,197	132,307	108,462
Non-interest income	12,262	11,583	37,642	33,788
Non-interest expense	37,011	34,134	111,384	100,387
Income before provision for income taxes	18,563	14,646	58,565	41,863
Provision for income taxes	4,141	2,773	13,486	8,112
Net income	14,422	11,873	45,079	33,751
Trust and Investment Services [Member]
Segment Reporting Information [Line Items]
Non-interest income	4,854	4,379	14,694	13,390
Non-interest expense	2,998	2,656	8,872	8,151
Income before provision for income taxes	1,856	1,723	5,822	5,239
Provision for income taxes	743	690	2,329	2,096
Net income	$1,113	$1,033	$3,493	$3,143