Mergers and Acquisitions - Contingent Consideration (Details) - USD ($)	3 Months Ended				9 Months Ended		12 Months Ended
	Apr. 02, 2017	Oct. 02, 2016	Mar. 27, 2016	Jun. 28, 2015	Jul. 02, 2017	Jun. 26, 2016	Oct. 02, 2016	Sep. 27, 2015
Mergers and Acquisitions
Increase (decrease) in contingent consideration					$ (7,149,000)
Gain (loss) on change in contingent consideration					7,149,000	$ (2,823,000)
Impairment of goodwill		$ 0
Contingent earn-out liability					3,500,000
Aggregate maximum of contingent consideration					$ 12,200,000
Minimum
Mergers and Acquisitions
Earn-out period					2 years
Maximum
Mergers and Acquisitions
Earn-out period					3 years
INDUS
Mergers and Acquisitions
Earn-out period			2 years
Potential maximum earn-out to be paid			$ 8,000,000
Potential earn-out to be paid each year			$ 4,000,000
Estimated potential earn-out (as a percent)			50.00%				59.00%
Minimum operating income threshold to earn contingent consideration during year one			$ 3,200,000
Minimum operating income threshold to earn contingent consideration during year two			3,600,000
Operating income to earn maximum consideration during the first year			3,600,000
Operating income to earn maximum consideration during the second year			4,000,000
Gain (loss) on change in contingent consideration	$ 5,000,000
Impairment of goodwill	0
Contingent earn-out liability	0	4,900,000	4,700,000				$ 4,900,000
Aggregate maximum of contingent consideration			8,000,000
CEG
Mergers and Acquisitions
Earn-out period				3 years
Potential maximum earn-out to be paid				$ 9,800,000
Potential earn-out to be paid each year				$ 3,250,000
Estimated potential earn-out (as a percent)				42.00%
Minimum operating income threshold to earn contingent consideration during year one				$ 2,000,000
Minimum operating income threshold to earn contingent consideration during year two				2,300,000
Minimum operating income threshold to earn contingent consideration during year three				2,600,000
Operating income to earn maximum consideration during the first year				4,500,000
Operating income to earn maximum consideration during the second year				4,800,000
Operating income to earn maximum consideration during the third year				5,100,000
Initial fair value of the contingent consideration				$ 4,100,000
Increase (decrease) in contingent consideration	(1,800,000)		1,800,000
Gain (loss) on change in contingent consideration	2,100,000		$ (1,800,000)
Impairment of goodwill	$ 0
Earn-out paid to former owners		2,300,000
Remaining Earn-out liability		$ 3,900,000
Other Acquisitions
Mergers and Acquisitions
Gain (loss) on change in contingent consideration						(1,000,000)
Contingent earn-out liability								$ 0
Earn-out paid to former owners						$ 1,000,000