Mergers and Acquisitions - Summary of Fair Value of Net Assets that Wesbanco Acquired from ESB (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Feb. 10, 2015
Assets
Loans	$ 700,800
ESB Financial Corporation [Member]
Assets
Cash and due from banks		8,485
Securities		486,891
Loans		700,849
Goodwill and other intangible assets		174,235
Accrued income and other assets		672,125
Total Assets		2,042,585
Liabilities
Deposits		1,246,992
Borrowings		433,454
Accrued expenses and other liabilities		23,170
Total liabilities		1,703,616
Purchase price		$ 338,969

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the fair value of the receivables acquired, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

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Amount of assets acquired at the acquisition date.

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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 investments in debt and equity securities, including, but not limited to, held-to-maturity, trading and available-for-sale expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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