Segment Reporting - Sales by Customer (Details) - Sales to major customers - Customer Concentration Risk	12 Months Ended
Dec. 28, 2019	Dec. 29, 2018
Customer A
Segment Reporting Information
Concentration risk percentage	12.00%	19.00%
Customer B
Segment Reporting Information
Concentration risk percentage		11.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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