Restructuring and Related Costs (Narrative) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Mar. 30, 2019	Mar. 31, 2018	Mar. 30, 2019	Mar. 31, 2018
2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 0	$ 0	$ 0	$ 0
2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Cost incurred to date	4,871,000		4,871,000
Employee Severance | 2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Cost incurred to date	880,000		880,000
Employee Severance | 2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0	321,000	130,000	414,000
Cost incurred to date	4,579,000		4,579,000
Facility Closing | 2017 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 25,000		$ 187,000
Cost incurred to date	$ 292,000		$ 292,000