Pension Plan (Details Textual) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012
Pension Plan (Textual) [Abstract]
Minimum required pension plan contribution	$ 5.3
Partial credit balance utilized for minimum required contribution	$ 2.1

Partial credit balance utilized for minimum required contribution.

No definition available.

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