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Consolidated Statements of Equity (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 27, 2020	Dec. 29, 2019	Dec. 30, 2018
ASU 2016-13 (Topic 326) [Member]
Cumulative impact tax	$ 2
ASU 2016-02 (Topic 842) [Member]
Cumulative impact tax		$ 196
ASU 2014-09 (Topic 606) [Member]
Cumulative impact tax			$ 250

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