Note 5 - Line of Credit (Details Textual) - Amegy [Member] - Credit Agreement After Fifth Amendment [Member] $ in Millions		6 Months Ended
Aug. 16, 2016 USD ($)	Jun. 30, 2017 USD ($)
Debt Agreement, Borrowing Base Percentage of Collateral Modified From		80.00%
Debt Agreement, Covenant Compliance, Minimum Net Worth		$ 20.0
Debt Instrument, Interest Rate, Stated Percentage	4.50%
Long-term Debt, Number of Monthly Payments, Principal and Interest	47
Debt Instrument, Amortization Period	5 years
Revolving Credit Facility [Member]
Debt Agreement, Maximum Borrowing Capacity		4.0
Term Loan [Member]
Debt Agreement, Maximum Borrowing Capacity		$ 3.0
Proceeds from Issuance of Long-term Debt	$ 2.7
Term Loan [Member] \| Prime Rate [Member]
Debt Instrument, Basis Spread on Variable Rate		0.50%
Standby Letters of Credit [Member]
Line of Credit Facility, Maximum Borrowing Capacity		$ 0.2

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Combined line of credit facility and term loan borrowing base percentage of collateral modified from.

+ References

No definition available.

+ Details

Name:	whlm_DebtAgreementBorrowingBasePercentageOfCollateralModifiedFrom
Namespace Prefix:	whlm_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents information about the Company’s minimum net worth covenant.

+ References

No definition available.

+ Details

Name:	whlm_DebtAgreementCovenantComplianceMinimumNetWorth
Namespace Prefix:	whlm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under a debt agreement on the amount that could be borrowed with a combination of, but not limited to, a line of credit and term loan.

+ References

No definition available.

+ Details

Name:	whlm_DebtAgreementMaximumBorrowingCapacity
Namespace Prefix:	whlm_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the amortization period for the debt instrument.

+ References

No definition available.

+ Details

Name:	whlm_DebtInstrumentAmortizationPeriod
Namespace Prefix:	whlm_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of the required monthly payments including both interest and principal payments for the term loan.

+ References

No definition available.

+ Details

Name:	whlm_LongTermDebtNumberOfMonthlyPaymentsPrincipalAndInterest
Namespace Prefix:	whlm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

Name:	us-gaap_DebtInstrumentAxis=whlm_CreditAgreementAfterFifthAmendmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=whlm_TermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_PrimeRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_StandbyLettersOfCreditMember
Namespace Prefix:
Data Type:	na
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Period Type: