Leases - Supplemental Cash Flow Information Related to Finance Leases (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 28, 2019	Jun. 28, 2019	Jun. 29, 2018
Leases [Abstract]
Amortization of finance lease right-of-use asset	$ 145	$ 306
Interest on finance lease liabilities	22	41
Cash paid for amounts included in the measurement of finance lease liabilities:
Operating cash flows	22	41
Financing cash flows	316	681	$ 881
Right-of-use assets obtained in exchange for new finance lease liabilities	$ 37	$ 679

Cash paid for amounts included in the measurement of finance lease liabilities.

No definition available.

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- Definition

Amount of interest expense on finance lease liability.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
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-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

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+ Details

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- Definition

Amount of interest paid on finance lease liability.

+ References

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- Definition

Amount of cash outflow for principal payment on finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 5
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-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

+ Details

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- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

+ References

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- References

No definition available.

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- Definition

Amount of increase in right-of-use asset obtained in exchange for finance lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971

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