CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	12 Months Ended
	Dec. 30, 2017	Dec. 31, 2016	Dec. 26, 2015
Statement of Stockholders' Equity [Abstract]
Cash dividends per share (in dollars per share)	$ 1.50	$ 1.50	$ 1.50
Number of shares acquired	0	441,949	1,435,488
Stock plan exercises; shares acquired (in shares)	145,866	16,777	112,995
Stock options exercised; shares issued (in shares)	284,574	109,893	169,493
Stock awards; shares issued (in shares)	42,846	15,700	10,329