Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Goodwill and Purchased Intangible Assets - Details of Purchased Intangible Assets (Detail) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Jul. 31, 2015	Feb. 28, 2015	Dec. 26, 2014	Sep. 25, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount			$ 31,487	$ 63,657
Accumulated Amortization			(14,663)	(18,705)
Carrying Value			16,824	44,952
American Integration Technologies LLC [Member] \| Customer relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount			19,000	19,000
Accumulated Amortization			(13,011)	(14,726)
Carrying Value			$ 5,989	4,274
Useful Life (in years)			7 years
American Integration Technologies LLC [Member] \| Trade name [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount			$ 1,900	1,900
Accumulated Amortization			(1,081)	(1,304)
Carrying Value			$ 819	596
Useful Life (in years)			6 years
American Integration Technologies LLC [Member] \| Intellectual Properties/Know-How [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount			$ 1,600	1,600
Accumulated Amortization			(571)	(743)
Carrying Value			$ 1,029	857
Useful Life (in years)			7 years
Marchi Thermal Systems Inc [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount		$ 23,370
Marchi Thermal Systems Inc [Member] \| Customer relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount		$ 9,900		9,900
Accumulated Amortization				(660)
Carrying Value				9,240
Useful Life (in years)		10 years	10 years
Marchi Thermal Systems Inc [Member] \| Trade name [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount		$ 1,170		1,170
Accumulated Amortization				(158)
Carrying Value				1,012
Useful Life (in years)		6 years	6 years
Marchi Thermal Systems Inc [Member] \| Intellectual Properties/Know-How [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount		$ 12,300		12,300
Accumulated Amortization				(919)
Carrying Value				11,381
Marchi Thermal Systems Inc [Member] \| Intellectual Properties/Know-How [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (in years)		8 years	8 years
Marchi Thermal Systems Inc [Member] \| Intellectual Properties/Know-How [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (in years)		12 years	12 years
Miconex [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 8,800
Miconex [Member] \| Customer relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 8,800			8,800
Accumulated Amortization				(195)
Carrying Value				8,605
Useful Life (in years)	7 years 6 months		7 years 6 months
UCT [Member] \| Trade name [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount			$ 8,987	8,987
Carrying Value			$ 8,987	$ 8,987