Goodwill and Intangible Assets Disclosure [Line Items]

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- Definition

Reduction in Employees, Percentage

+ References

No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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-Publisher FASB
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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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- Definition

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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- Definition

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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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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Goodwill and Acquired Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 02, 2017	Jul. 03, 2016	Jul. 02, 2017	Jul. 03, 2016	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Line Items]
Goodwill impairment		$ 254,946		$ 254,946
Goodwill	$ 242,215		$ 242,215		$ 223,343
Intangible assets impairment		83,339		83,339
Acquired intangible assets amortization	8,166	$ 16,244	16,118	36,238
Wireless Test
Goodwill and Intangible Assets Disclosure [Line Items]
Employee reduction, percentage		11.00%
Goodwill impairment		$ 254,946		254,946
Goodwill	$ 7,976	8,000	$ 7,976	8,000	$ 7,976
Intangible assets impairment		$ 83,339		$ 83,339
Wireless Test \| Sales Revenue, Segment \| Customer Concentration Risk \| Minimum
Goodwill and Intangible Assets Disclosure [Line Items]
Concentration risk, percentage		51.00%
Wireless Test \| Sales Revenue, Segment \| Customer Concentration Risk \| Maximum
Goodwill and Intangible Assets Disclosure [Line Items]
Concentration risk, percentage		73.00%