Fronting fee interest rate percentage for issued letters of credit, excluding interest rate spread.

No definition available.

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- Definition

The Base Rate is the greater of the prime rate (as announced by Bank of America), the federal funds rate plus an additional rate or the 30 day LIBOR rate plus an additional rate.

+ References

No definition available.

+ Details

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- Definition

Current liquidation value of the pledged real estate as of the reporting date for the purpose of computing the revolving credit facility borrowing limit. This is the maximum liquidation value of the pledged real estate less the quarterly reduction. This borrowing limit is in addition to the borrowing limit as a percentage of eligible accounts receivable.

+ References

No definition available.

+ Details

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- Definition

Maximum liquidation value of the pledged real estate for purposes of calculating the revolving credit facility borrowing limit.

+ References

No definition available.

+ Details

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- Definition

Revolving credit facility borrowing limit as a percentage of eligible accounts receivable. This borrowing limit is in addition to the current liquidation value of the pledged real estate as of the reporting date for the purpose of computing the revolving credit facility borrowing limit.

+ References

No definition available.

+ Details

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- Definition

Quarterly reduction of the maximum liquidation value of the pledged real estate for the purposes of computing the revolving credit facility borrowing limit.

+ References

No definition available.

+ Details

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- Definition

Cash and cash equivalents under control agreements as of the reporting date used to calculate liquidity for the purposes of meeting the excess liquidity terms under the revolving credit facility.

+ References

No definition available.

+ Details

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- Definition

The minimum liquidity required to be maintained in order to meet the terms of the revolving credit facility.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Total liquidity as of the reporting date consisting of the unused portion of the revolving credit facility and cash and cash equivalents under control agreements for the purposes of meeting the excess liquidity terms under the revolving credit facility.

+ References

No definition available.

+ Details

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- Definition

Revolving credit facility, utilization threshold

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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

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

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Balance Type:	credit
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- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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- Definition

Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

+ References

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- 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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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

- 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

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: 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(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: 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 3: 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

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Period Type:	instant

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LONG-TERM DEBT Revolving Credit Facility Narrative (Details) - USD ($) $ in Thousands		12 Months Ended
	Jun. 30, 2014	Dec. 31, 2017	Jan. 01, 2017
Revolving Credit Facility [Line Items]
Total		$ 118,756	$ 137,629
Bank of America, N.A. and Wells Fargo Capital Finance, LLC
Revolving Credit Facility [Line Items]
Total		$ 95,900	$ 112,507
Revolving credit facility, interest rate description	one-month
Revolving credit facility, interest rate at period end		3.13%
Bank of America, N.A. and Wells Fargo Capital Finance, LLC \| Revolving Credit Facility
Revolving Credit Facility [Line Items]
Revolving Credit Facility, maximum borrowing capacity	$ 300,000
Revolving credit facility, current borrowing capacity		$ 221,545
Total		95,900
Revolving credit facility, amount outstanding		8,264
Revolving credit facility,, utilization threshold	25.00%
Percent of Eligible Billed Accounts Receivable \| Bank of America, N.A. and Wells Fargo Capital Finance, LLC \| Revolving Credit Facility
Revolving Credit Facility [Line Items]
Revolving credit facility borrowing limits, percent of accounts receivable	90.00%
Percent of Eligible Unbilled Accounts Receivable \| Bank of America, N.A. and Wells Fargo Capital Finance, LLC \| Revolving Credit Facility
Revolving Credit Facility [Line Items]
Revolving credit facility borrowing limits, percent of accounts receivable	85.00%
Percent of Eligible Accounts Receivable \| Bank of America, N.A. and Wells Fargo Capital Finance, LLC \| Revolving Credit Facility
Revolving Credit Facility [Line Items]
Revolving credit facility borrowing limits, percent of accounts receivable	15.00%
Liquidation Value of Tacoma Headquarters Office Building \| Bank of America, N.A. and Wells Fargo Capital Finance, LLC \| Revolving Credit Facility
Revolving Credit Facility [Line Items]
Revolving credit facility borrowing limits, liquidation value requirement, pledged real estate	$ 17,400
Revolving credit facility borrowing limits, quarterly reduction, liquidation value of pledged real estate	$ 400
Revolving credit facility borrowing limits, liquidation value of pledged real estate		11,770
Revolving Credit Facility, Liquidity Requirement Component \| Bank of America, N.A. and Wells Fargo Capital Finance, LLC \| Revolving Credit Facility
Revolving Credit Facility [Line Items]
Revolving credit facility, remaining borrowing capacity		117,381
Revolving credit facility, cash and cash equivalents under control agreements		18,974
Revolving credit facility, total liquidity		$ 136,355
London Interbank Offered Rate (LIBOR) \| Bank of America, N.A. and Wells Fargo Capital Finance, LLC \| Revolving Credit Facility
Revolving Credit Facility [Line Items]
Revolving credit facility, additional base rate	1.00%	1.75%
Letters of credit, additional basis rate	0.125%
Base rate \| Bank of America, N.A. and Wells Fargo Capital Finance, LLC \| Revolving Credit Facility
Revolving Credit Facility [Line Items]
Revolving credit facility, additional base rate	0.50%	1.375%
Minimum \| Revolving Credit Facility, Liquidity Requirement Component \| Bank of America, N.A. and Wells Fargo Capital Finance, LLC \| Revolving Credit Facility
Revolving Credit Facility [Line Items]
Revolving credit facility, liquidity requirement	$ 37,500
Minimum \| London Interbank Offered Rate (LIBOR) \| Bank of America, N.A. and Wells Fargo Capital Finance, LLC \| Revolving Credit Facility
Revolving Credit Facility [Line Items]
Debt Instrument, basis spread on variable rate	1.25%
Minimum \| Base rate \| Bank of America, N.A. and Wells Fargo Capital Finance, LLC \| Revolving Credit Facility
Revolving Credit Facility [Line Items]
Debt Instrument, basis spread on variable rate	0.25%
Maximum \| London Interbank Offered Rate (LIBOR) \| Bank of America, N.A. and Wells Fargo Capital Finance, LLC \| Revolving Credit Facility
Revolving Credit Facility [Line Items]
Debt Instrument, basis spread on variable rate	2.00%
Maximum \| Base rate \| Bank of America, N.A. and Wells Fargo Capital Finance, LLC \| Revolving Credit Facility
Revolving Credit Facility [Line Items]
Debt Instrument, basis spread on variable rate	1.00%
Less than 25% utilization \| Bank of America, N.A. and Wells Fargo Capital Finance, LLC \| Revolving Credit Facility
Revolving Credit Facility [Line Items]
Revolving credit facility, unused capacity, commitment fee percentage	0.375%
Greater than or equal to 25% utilization \| Bank of America, N.A. and Wells Fargo Capital Finance, LLC \| Revolving Credit Facility
Revolving Credit Facility [Line Items]
Revolving credit facility, unused capacity, commitment fee percentage	0.25%