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	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Segment Reporting Information [Line Items]
Gross profit	$ 98,798	$ 79,635	$ 195,844	$ 169,007
Research and development	17,567	15,421	34,247	31,039
Selling, general and administrative	33,269	32,239	64,136	66,830
Acquisition costs		271	30	499
Restructuring	219		1,007	747
Amortization of intangible assets	1,709	1,044	3,380	1,454
Income from operations	46,034	30,660	93,044	68,438
Net interest income	790	231	1,294	466
Income before income taxes	46,824	30,891	94,338	68,904
Provision for income taxes	13,604	9,667	27,332	16,435
Net income	33,220	21,224	67,006	52,469
Operating Segments [Member] \| Advanced Manufacturing Capital Equipment [Member]
Segment Reporting Information [Line Items]
Gross profit	82,552	59,918	161,240	127,025
Operating Segments [Member] \| Global Service [Member]
Segment Reporting Information [Line Items]
Gross profit	10,366	9,683	19,968	18,080
Operating Segments [Member] \| Asia Region Sales [Member]
Segment Reporting Information [Line Items]
Gross profit	7,815	6,319	14,736	15,396
Operating Segments [Member] \| Other [Member]
Segment Reporting Information [Line Items]
Gross profit	5,697	6,678	12,539	13,425
Corporate and Eliminations [Member]
Segment Reporting Information [Line Items]
Gross profit	$ (7,632)	$ (2,963)	$ (12,639)	$ (4,919)

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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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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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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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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