Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2015	Dec. 31, 2014
Accounting Policies [Abstract]
Minimum past due of loans for nonaccrual status	90 days
Loans with identified weakness and principal balance	$ 500,000	$ 100,000
Assignment of valuation allowance for specified amount of loan	$ 500,000

The maximum amount that a loan can be to measure for impairment using the allocation rate.

No definition available.

Name:	wbhc_MaximumAmountOfImpairedLoansForMeasurementUsingAllocationRate
Namespace Prefix:	wbhc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant