Consolidated Statements of Changes in Stockholders' Equity (Parenthetical) - $ / shares	12 Months Ended
Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Cash dividend per share	$ 1.00	$ 1.00	$ 1.00
Class B Common Stock [Member]
Cash dividend per share	$ 1.00	$ 1.00	$ 1.00
Class B common stock shares issued	20,296	21,020	20,920

Number of new stock issued during the period.

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