Lease Commitments - Balance Sheet, Operating Lease Term and Discount Rate (Details) - USD ($) $ in Thousands	Sep. 28, 2019	Dec. 30, 2018	Dec. 29, 2018
Assets
Operating ROU assets	$ 21,598	$ 26,100
Liabilities
Current operating lease liabilities	6,926		$ 0
Non-current operating lease liabilities	17,237	$ 29,400
Total lease liabilities	$ 24,163
Weighted-average remaining lease term (years)	4 years 2 months 8 days
Weighted-average discount rate	5.18%

Assets, Lessee [Abstract]

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- Definition

Liabilities, Lessee [Abstract]

+ References

No definition available.

+ Details

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

+ References

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

+ References

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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- Definition

Weighted average discount rate for operating lease calculated at point in time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
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-Topic 842
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