Mergers and Acquisitions - Summary of Purchase Price of Acquisition and Resulting Goodwill (Detail) - Your Community Bankshares, Inc [Member] - USD ($) $ in Thousands		12 Months Ended
Sep. 09, 2016	Dec. 31, 2017
Purchase Price:
Fair value of WesBanco shares issued	$ 177,149
Cash consideration for outstanding YCB shares	43,349
Total purchase price	220,498
Fair value of:
Tangible assets acquired	1,398,183
Core deposit and other intangible assets acquired	11,957
Liabilities assumed	(1,330,887)
Net cash received in the acquisition	48,212
Fair value of net assets acquired	127,465
Goodwill recognized	$ 93,033	$ 93,033

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The amount of tangible assets recognized as of the acquisition date.

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