Retirement Plans (Narrative) (Details) $ in Thousands	12 Months Ended
Dec. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)
Retirement Plans [Abstract]
Number of supplemental retirement plans	3
Defined Benefit Plan, Benefit Obligation	$ 4,914
Retirement Plans, Accumulated Benefit Obligation	$ 14,508	$ 11,176
Deferred Compensation Arrangement with Individual, Requisite Service Period	6 years
2018	$ 1,013

Minimum period the individual is required to perform services to be fully vested under the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6409961&loc=d3e20487-108367

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

+ 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 (a)
-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
-Glossary Projected Benefit Obligation
-URI http://asc.fasb.org/extlink&oid=6522206

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Accumulated Postretirement Benefit Obligation
-URI http://asc.fasb.org/extlink&oid=6503904

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- References

No definition available.

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- Definition

Number of supplemental retirement plans covering highly compensated employees.

+ References

No definition available.

+ Details

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- Definition

This represents the present value of the accumulated benefits of the Company’s non-qualified supplemental executive retirement plan (SERP) and the non-qualified deferred compensation plan for pharmacists , which are recognized in the balance sheet as a noncurrent liability. Both the SERP and the deferred compensation plan for pharmacists are designed to provide retirement benefits and salary deferral opportunities because of limitations imposed by the Internal Revenue Code and the Regulations implemented by the Internal Revenue Service. The plans are unfunded and accounted for on an accrual basis.

+ References

No definition available.

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