Commitments and Contingent Liabilities - Total Contractual Amount for All Off-Balance Sheet Commitments (Detail) $ in Thousands	Mar. 31, 2016 USD ($)
Standby Letters of Credit [Member]
Loss Contingencies [Line Items]
Contractual amount for off-balance sheet commitments	$ 34,607
Commitments to Extend Credit [Member]
Loss Contingencies [Line Items]
Contractual amount for off-balance sheet commitments	$ 396,060

The contractual amount associated with the obligations, contingent liabilities, and other exposures relating to off-balance sheet arrangements such as unfunded loan commitments, contractual obligations, and recourse from loans securitized.

No definition available.

Name:	wbhc_ContractualAmountForOffBalanceSheetCommitments
Namespace Prefix:	wbhc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant