Loans and the Allowance for Credit Losses - Summary of Changes in ACL (Parenthetical) (Detail) $ in Millions	9 Months Ended
Sep. 30, 2026 USD ($)
Receivables [Abstract]
Charge-offs on acquired loan portfolio prior acquisition	$ 22.7

Financing receivable charge offs on acquired loan portfolio prior to acquisition.

No definition available.

Name:	wsbc_FinancingReceivableChargeOffsOnAcquiredLoanPortfolioPriorToAcquisition
Namespace Prefix:	wsbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration