Segment Information (Details) $ in Thousands	3 Months Ended
	Jan. 04, 2020 USD ($) segment	Dec. 29, 2018 USD ($)
Segment Reporting Information [Line Items]
Number of Operating Segments | segment	2
Net sales	$ 153,217	$ 154,926
Gross profit	21,300	19,110
United States
Segment Reporting Information [Line Items]
Net sales	136,266	151,485
Canada
Segment Reporting Information [Line Items]
Net sales	13,156	3,076
Rest of world
Segment Reporting Information [Line Items]
Net sales	3,795	365
Operating Segments
Segment Reporting Information [Line Items]
Gross profit	21,300	19,110
Operating Segments | Bus
Segment Reporting Information [Line Items]
Net sales	134,772	139,210
Gross profit	14,867	13,515
Operating Segments | Parts
Segment Reporting Information [Line Items]
Net sales	18,445	15,716
Gross profit	6,433	5,595
Intersegment Eliminations | Parts
Segment Reporting Information [Line Items]
Net sales	$ 1,200	$ 600