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GNU Interest (Details) - USD ($) $ in Thousands		12 Months Ended
	Dec. 18, 2018	Jan. 02, 2021	Dec. 28, 2019	Dec. 29, 2018
GNU Interest
GNU gain on sale of business assets		$ 0	$ 0	$ 258
GNU
GNU Interest
Percentage of ownership interest held by the entity	55.89%
GNU | Disposal Group, Disposed of by Sale, Not Discontinued Operations | GNU
GNU Interest
GNU gain on sale of business assets				$ 300

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Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
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-Publisher FASB
-Name Accounting Standards Codification
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-Topic 360
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-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230

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