Consolidated Balance Sheet (Parenthetical) - USD ($) $ in Thousands	Sep. 29, 2017	Sep. 30, 2016	Oct. 02, 2015	Oct. 31, 2014
Statement Of Financial Position [Abstract]
Accounts receivable, allowances	$ 16,035	$ 17,028	$ 10,050	$ 10,023
Common stock, par value	$ 0.20	$ 0.20
Common stock, shares authorized	60,000,000	60,000,000
Common stock, shares issued	33,117,473	32,564,252	32,378,185
Treasury stock, shares repurchased	3,135,927	3,135,927	2,831,350