Major Customers and Export Sales - Foreign Revenues by Country as Percentage of Total Foreign Revenue (Detail)	3 Months Ended
	Dec. 31, 2016	Jan. 02, 2016
Egypt
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue From Foreign Countries As Percentage Of Foreign Revenue	0.00%	46.00%
Taiwan
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue From Foreign Countries As Percentage Of Foreign Revenue	16.00%	0.00%
Saudi Arabia
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue From Foreign Countries As Percentage Of Foreign Revenue	6.00%	54.00%
Jordan
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue From Foreign Countries As Percentage Of Foreign Revenue	78.00%	0.00%