Strategic Technology Transactions, Goodwill and Purchased Intangible Assets - Changes in Carrying Value of Goodwill by Reportable Segment (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 27, 2014	Dec. 27, 2014	Dec. 28, 2013
Segment Reporting Information [Line Items]
Goodwill		$ 71,313us-gaap_Goodwill	$ 58,756us-gaap_Goodwill
Additions net of adjustments			10,930us-gaap_GoodwillAcquiredDuringPeriod
Impact of currency exchange		(5,126)us-gaap_GoodwillTranslationAdjustments	1,627us-gaap_GoodwillTranslationAdjustments
Impairment of goodwill - (See Note 3)		(3,055)us-gaap_GoodwillImpairmentLoss
Goodwill	63,132us-gaap_Goodwill	63,132us-gaap_Goodwill	71,313us-gaap_Goodwill
Semiconductor Equipment [Member]
Segment Reporting Information [Line Items]
Goodwill		67,983	55,520
Additions net of adjustments			10,930
Impact of currency exchange		(4,851)	1,533
Goodwill	63,132	63,132	67,983
Microwave Communications Equipment [Member]
Segment Reporting Information [Line Items]
Goodwill		3,330	3,236
Impact of currency exchange		(275)	94
Impairment of goodwill - (See Note 3)	(3,055)	(3,055)
Goodwill			$ 3,330

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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