Business Segment, Geographic Area, Product and Significant Customer Information - Reconciliation of Segment Gross Profit to Consolidated Net Income (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Segment Reporting Information [Line Items]
Gross profit	$ 205,547	$ 77,913
Research and development	33,282	17,227
Selling, general and administrative	74,220	33,950
Acquisition and integration costs	1,442	2,494
Restructuring	522	0
Amortization of intangible assets	12,501	1,683	$ 1,683
Income from operations	83,580	22,559
Interest and other (expense) income, net	(6,295)	1,246
Income before income taxes	77,285	23,805
Provision for income taxes	12,225	6,242
Net income	65,060	17,563
Vacuum & Analysis [Member]
Segment Reporting Information [Line Items]
Gross profit	128,924	$ 77,913
Light & Motion [Member]
Segment Reporting Information [Line Items]
Gross profit	$ 76,623

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.

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

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