Retirement Plans (Narrative) (Details) $ in Millions	12 Months Ended
Dec. 28, 2019 USD ($)	Dec. 29, 2018 USD ($)
Retirement Plans [Abstract]
Number of supplemental retirement plans	1
Defined Benefit Plan, Benefit Obligation	$ 4.2
Retirement Plans, Accumulated Benefit Obligation	$ 19.0	$ 14.7
Service period to be fully vested	3 years
Estimated payments in next year	$ 1.0

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://fasb.org/us-gaap/role/ref/legacyRef
-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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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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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