Retirement Plans (Schedule of Multi-employer Plans) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Jan. 02, 2016
Multiemployer Plans [Line Items]
Contributions	$ 588	$ 554
Multiemployer Plans, Pension [Member] \| GCC/IBT National Pension Fund [Member] \| Oregon Location [Member]
Multiemployer Plans [Line Items]
EIN	526118568
Pension Plan Number	001
Pension Protection Act Reported Status	Red	Red
FIP/RP Status	Implemented
Contributions	$ 183	$ 219
Surcharge imposed	No
Expiration Date of Collective Bargaining Agreement	Jun. 30, 2019
Multiemployer Plans, Pension [Member] \| GCC/IBT National Pension Fund [Member] \| Missouri Location [Member]
Multiemployer Plans [Line Items]
EIN	526118568
Pension Plan Number	001
Pension Protection Act Reported Status	Red	Red
FIP/RP Status	Implemented
Contributions	$ 177	$ 177
Surcharge imposed	No
Expiration Date of Collective Bargaining Agreement	Feb. 26, 2017
Multiemployer Plans, Pension [Member] \| CWA/ITU Negotiated Pension Plan [Member] \| Virginia Location [Member]
Multiemployer Plans [Line Items]
EIN	136212879
Pension Plan Number	001
Pension Protection Act Reported Status	Red	Red
FIP/RP Status	Implemented
Contributions	$ 228	$ 158
Surcharge imposed	No
Expiration Date of Collective Bargaining Agreement	Mar. 01, 2018

The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation 12B
-Number 240
-Section 12b
-Subsection 1

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Three digit plan number for a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=49170332&loc=SL14450657-114947

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Amount of contributions made to multiemployer plans by the employer. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=49170332&loc=SL14450702-114947

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 9
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Section 50
-Paragraph 5
-Subparagraph (e)(1)
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- Definition

Indicate the multiemployer plan's certified zone status as currently required by the Pension Protection Act of 2006 or a subsequent amendment thereof. The zone status categories are red (critical status), orange (seriously endangered), yellow (endangered), and green (none of the above). The acceptable values are "red", "orange", "yellow", "green", "other", and "NA". A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=49170332&loc=SL14450657-114947

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Expiration date of the collective bargaining arrangement requiring contributions to the multiemployer plan, in CCYY-MM-DD format. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 5
-Subparagraph (d)
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Indicate whether a funding improvement plan or rehabilitation plan has been implemented or is pending for a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. The acceptable values are "no", "pending", "implemented", "other", and "NA".

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
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-Paragraph 5
-Subparagraph (f)(1)
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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.

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No definition available.

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- Definition

Indicate whether the employer paid a surcharge to the pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. The acceptable values are "no", "yes", and "NA".

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
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