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

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: 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))

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- Details

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- Definition

Amount of the required periodic payments including both interest and principal payments.

+ 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)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Period Type:	instant

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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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

+ Details

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Definition

The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. For a classified balance sheet represents the current portion only (the noncurrent portion has a separate concept); there is a separate and distinct element for unclassified presentations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 1

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.1)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of short-term debt and current maturity of long-term debt. Excludes capital lease obligations.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The minimum threshold for EBITDA in order to request an extension of the maturity date at the time specified under the agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Minimum amount, as a percentage of actual tangible net worth, to included in calculation of minimum tangible net worth to be maintained under terms of agreement.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Definition

Represents the percentage of interest rate that will be increased in case of default under customary negative covenants of credit agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	wldn_
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- Definition

The maximum total leverage ratio of total funded debt (measured as the sum of all obligations for borrowed money, including subordinated debt, plus all capital lease obligations) plus capital leases plus financial letters of credit to EBITDA as a covenant under the credit agreement.

+ References

No definition available.

+ Details

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- Definition

The minimum fixed charge coverage ratio (measured as the sum of EBITDA plus rent expense less unfinanced capital expenditures divided by the sum of rent expense plus principal payments plus cash taxes plus cash interest plus restricted payments plus distributions) as a covenant under the credit agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the step ups amount equal to as a percentage of net income (if positive) required for tangible net worth as a covenant under the credit agreement.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The period of time in which the maturity date may be extended under the terms of the agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	wldn_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of eligible accounts receivable used to determine maximum borrowing base.

+ References

No definition available.

+ Details

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Namespace Prefix:	wldn_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of the lower of cost or market value of eligible inventory used to determine maximum borrowing base.

+ References

No definition available.

+ Details

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Namespace Prefix:	wldn_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the amount of total consideration for all permitted acquisitions (including potential future earn-out obligations), as customary negative covenants under the credit agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	wldn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the amount of total consideration for individual permitted acquisitions (including potential future earn-out obligations), as customary negative covenants under the credit agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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- Details

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Period Type:

- Details

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- Details

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- Details

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- Details

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- Details

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DEBT OBLIGATIONS (Details) (USD $)	0 Months Ended		13 Months Ended	9 Months Ended	1 Months Ended
DEBT OBLIGATIONS (Details) (USD $)	Dec. 23, 2013	Mar. 24, 2014	Jan. 31, 2014	Aug. 31, 2014	Jan. 02, 2015	Dec. 27, 2013	Mar. 20, 2014
Debt obligations
Total debt obligations, excluding capital lease obligations					$ 355,000	$ 517,000
Less current portion					355,000	517,000
Revolving Credit Facility \| Wells Fargo
Debt obligations
Maximum borrowing capacity	5,000,000						75,905
Fee on unused commitments (as a percent)	0.25%
Revolving Credit Facility \| BMO
Debt obligations
Maximum borrowing capacity		7,500,000
Restricted cash					0
Ebitda threshold as of the 3rd fiscal quarter of 2015		5,000,000
Period in which maturity date may be extended		1 year
Maximum total leverage ratio of total funded debt to EBITDA		2.00
Minimum fixed charge coverage ratio		1.25
Minimum tangible net worth required to be maintained (as a percent)		85.00%
Step ups amount equal to net income required to be maintained (as a percent)		50.00%
Percentage of increased interest rate in case of default		2.00%
Revolving Credit Facility \| Maximum \| BMO
Debt obligations
Total consideration for all permitted acquisitions		2,500,000
Total consideration for individual permitted acquisitions		750,000
Revolving Credit Facility \| LIBOR \| Wells Fargo
Debt obligations
Spread on floating interest rate (as a percent)	2.25%
Revolving line of credit \| BMO
Debt obligations
Percentage of eligible accounts receivable used to determine maximum borrowing base		75.00%
Percentage of the lower of cost or market value of eligible inventory used to determine maximum borrowing base		50.00%
Borrowings outstanding					0
Amount available for borrowing					7,500,000
Revolving line of credit \| Maximum \| BMO
Debt obligations
Fee on unused commitments (as a percent)		0.30%
Revolving line of credit \| LIBOR \| BMO
Debt obligations
Spread on floating interest rate (as a percent)		1.75%
Revolving line of credit \| Base rate \| BMO
Debt obligations
Spread on floating interest rate (as a percent)		0.75%
Standby letter of credit sub-facility \| BMO
Debt obligations
Maximum borrowing capacity		5,000,000
Delayed draw term loan facility \| BMO
Debt obligations
Maximum borrowing capacity		2,500,000
Amount available for borrowing					2,500,000
Notes payable for vehicles
Debt obligations
Total debt obligations, excluding capital lease obligations						7,000
Maturity term			36 months
Interest rate (as a percent)			1.90%
Monthly principal and interest installment (in dollars)			6,000
Notes bearing interest at 1.9 percent payable through August, 2014
Debt obligations
Total debt obligations, excluding capital lease obligations						462,000
Maturity term				9 months
Interest rate (as a percent)				1.90%
Monthly principal and interest installment (in dollars)				28,000
Notes bearing interest at 1.9 percent payable through August, 2015
Debt obligations
Total debt obligations, excluding capital lease obligations					352,000
Maturity term					9 months
Interest rate (as a percent)					1.80%
Monthly principal and interest installment (in dollars)					50,000
Other
Debt obligations
Total debt obligations, excluding capital lease obligations					$ 3,000	$ 48,000