Schedule of Restructuring and Related Costs (Detail) - USD ($) $ in Thousands	9 Months Ended
	Jul. 01, 2016	Jun. 26, 2015
Restructuring Cost And Reserve [Line Items]
Exit & Relocation of Facilities	$ 4,269	$ 8,614
Write-Off of Property, Plant & Equipment	27	834
Severance	569	2,293
Restructuring charges	4,865	11,741
Cost of Sales
Restructuring Cost And Reserve [Line Items]
Exit & Relocation of Facilities	2,258	4,359
Write-Off of Property, Plant & Equipment	27	791
Severance	150	529
Restructuring charges	2,435	5,679
Restructuring Charges
Restructuring Cost And Reserve [Line Items]
Exit & Relocation of Facilities	2,011	4,255
Write-Off of Property, Plant & Equipment	0	43
Severance	419	1,764
Restructuring charges	$ 2,430	$ 6,062