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

Business combination recognized identifiable assets acquired and liabilities assumed receivables on sale of available for sale securities.

No definition available.

Name:	wsbc_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedReceivablesOnSaleOfAvailableForSaleSecurities
Namespace Prefix:	wsbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant