Defined Benefit Plans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 29, 2017	Mar. 30, 2016	Dec. 28, 2016
Components of net periodic benefit cost [Abstract]
Additional minimum pension liability	$ 900		$ 900
Pension Plan [Member]
Components of net periodic benefit cost [Abstract]
Service cost	0	$ 105
Net periodic benefit cost	0	105
Other Defined Benefit Plans [Member]
Components of net periodic benefit cost [Abstract]
Interest cost	21	23
Amortization of net loss	23	21
Net periodic benefit cost	44	44
Employer contributions	100	$ 100
Estimated employer contributions remainder of current fiscal year	$ 100

After tax amount of additional minimum pension liability not yet recognized as a net periodic pension cost.

No definition available.

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- Definition

The amount of gains or losses recognized in net periodic benefit cost.

+ References

+ Details

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- Definition

Amount of contributions made by the employer to defined benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(ii)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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-Publisher FASB
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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

+ References

+ Details

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- Definition

The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

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- References

No definition available.

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- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Service Cost (Component of Net Periodic Pension Cost)
-URI http://asc.fasb.org/extlink&oid=6525008

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan in the current remaining fiscal period.

+ References

No definition available.

+ Details

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