Consolidated Statements of Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Sep. 28, 2019	Sep. 29, 2018	Sep. 30, 2017
Income Statement [Abstract]
Net sales	$ 3,164,434	$ 2,873,508	$ 2,528,052
Cost of sales	2,872,596	2,615,908	2,272,197
Gross profit	291,838	257,600	255,855
Selling and administrative expenses	148,105	139,317	125,947
Restructuring costs	1,678	0	0
Operating income	142,055	118,283	129,908
Other income (expense):
Interest expense	(12,853)	(12,226)	(13,578)
Interest income	1,949	4,696	5,042
Miscellaneous, net	(5,196)	(3,143)	451
Income before income taxes	125,955	107,610	121,823
Income tax expense	17,339	94,570	9,761
Net income	$ 108,616	$ 13,040	$ 112,062
Earnings per share:
Basic (in dollars per share)	$ 3.59	$ 0.40	$ 3.33
Diluted (in dollars per share)	$ 3.50	$ 0.38	$ 3.24
Weighted average shares outstanding:
Basic (in shares)	30,271	33,003	33,612
Diluted (in shares)	31,074	33,919	34,553
Other comprehensive (loss) income:
Derivative instrument fair value adjustment	$ 1,050	$ (3,942)	$ 2,405
Foreign currency translation adjustments	(6,855)	(3,058)	4,155
Other comprehensive (loss) income	(5,805)	(7,000)	6,560
Total comprehensive income	$ 102,811	$ 6,040	$ 118,622