Common stock units issued under plan.

No definition available.

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- Definition

Defined benefit plan, guaranteed return.

+ References

No definition available.

+ Details

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- Definition

The amount of payment into the fund established for purposes of making future disbursements to the individual in accordance with the terms and understanding of the deferred compensation arrangement.

+ References

No definition available.

+ 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

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Expected Long-Term Rate of Return on Plan Assets
-URI http://asc.fasb.org/extlink&oid=6512046

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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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

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (j)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

+ Details

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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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- Details

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- Details

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Deferred Compensation and Other Benefits - Additional Information (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Apr. 01, 2016	Dec. 31, 2017
ESBP [Member]
Deferred Compensation Text Details [Line Items]
Benefit plan, employer contributions	$ 200,000	$ 200,000
ESBP [Member] \| Forecast [Member]
Deferred Compensation Text Details [Line Items]
Estimated 2017 full year benefit payments			$ 700,000
NDBP [Member]
Deferred Compensation Text Details [Line Items]
Net periodic pension cost	$ 14,000	18,000
Targeted minimum return	4.00%
Guaranteed return	4.00%
Key Employee Non Qualified Deferred Compensation Plan [Member]
Deferred Compensation Text Details [Line Items]
Benefit plan, employer contributions	$ 100,000	$ 200,000
Key Employee Non Qualified Deferred Compensation Plan [Member] \| Deferred Compensation and Other Benefits [Member]
Deferred Compensation Text Details [Line Items]
Common stock units issued under plan	0	5,000
Non Employee Director Deferred Compensation Plan [Member]
Deferred Compensation Text Details [Line Items]
Benefit plan, employer contributions	$ 100,000	$ 100,000