Consolidated Condensed Statements of Changes in Equity (Unaudited) (Parenthetical) - $ / shares	3 Months Ended	6 Months Ended
Jul. 01, 2018	Jul. 02, 2017	Jul. 01, 2018	Jul. 02, 2017
Cash dividend per share	$ 0.25	$ 0.25	$ 0.50	$ 0.50
Class B Common Stock [Member]
Cash dividend per share	$ 0.25	$ 0.25	$ 0.50	$ 0.50
Class B common stock shares issued			20,296	21,020

Number of new stock issued during the period.

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