Mergers and Acquisitions - Summary of Purchase Price of Acquisition and Resulting Goodwill (Detail) - First Sentry Bancshares, Inc. [Member] $ in Thousands	Apr. 05, 2018 USD ($)
Purchase Price:
Fair value of WesBanco shares issued	$ 107,347
Cash consideration for outstanding FTSB shares	975
Total purchase price	108,322
Fair value of:
Tangible assets acquired	610,712
Core deposit and other intangible assets acquired	8,237
Liabilities assumed	(663,970)
Net cash received in the acquisition	87,124
Fair value of net assets acquired	42,103
Goodwill recognized	$ 66,219

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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