Segment Information (Details) $ in Thousands	3 Months Ended	9 Months Ended
Jul. 02, 2016 USD ($)	Jul. 04, 2015 USD ($)	Jul. 02, 2016 USD ($) segment	Jul. 04, 2015 USD ($)
Segment Reporting Information [Line Items]
Number of Operating Segments \| segment			2
Net sales	$ 323,055	$ 262,653	$ 645,596	$ 611,504
Gross profit	46,808	36,662	90,675	79,170
United States
Segment Reporting Information [Line Items]
Net sales	298,532	257,522	591,549	565,854
Canada
Segment Reporting Information [Line Items]
Net sales	21,642	4,585	46,261	42,032
Rest of world
Segment Reporting Information [Line Items]
Net sales	2,881	546	7,786	3,618
Operating Segments
Segment Reporting Information [Line Items]
Gross profit	46,808	36,662	90,675	79,170
Operating Segments \| Bus
Segment Reporting Information [Line Items]
Net sales	309,432	248,487	604,832	569,693
Gross profit	41,594	31,670	75,108	63,915
Operating Segments \| Parts
Segment Reporting Information [Line Items]
Net sales	13,623	14,166	40,764	41,811
Gross profit	$ 5,214	$ 4,992	$ 15,567	$ 15,255

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1,2)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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