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Number of customer related to credit concentration risk of net sales.

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Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) Customer	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Jan. 01, 2018 USD ($)
Change in Contract with Customer, Liability [Line Items]
Retained earnings opening balance sheet adjustment for Topic 606 adoption	$ 1,084,797	$ 795,698
Minimum period of company's research and development projects	3 months
Maximum period of company's research and development projects	30 months
Vesting period	3 years
Maximum maturity period of liquid investments	3 years
Maturity dates for short-term investments	12 months
Amortization period of leasehold improvements	Shorter of the lease term or the estimated useful life of the leased asset.
Asset impairment charge		6,719	$ 5,000
Increase (decrease) in valuation allowance on state tax credit carryforwards	$ 4,307	1,102	6,400
Valuation allowance	$ 17,936	$ 13,629	$ 12,527
Minimum percentage of recognition of tax benefits from uncertain tax positions	50.00%
U.S. federal corporate income tax rate	21.00%	35.00%	35.00%
Accounting Standards Codification Topic 606 adjustment [Member]
Change in Contract with Customer, Liability [Line Items]
Retained earnings opening balance sheet adjustment for Topic 606 adoption				$ 1,809
Contract assets	$ 3,624			$ 3,065
Other Expense [Member]
Change in Contract with Customer, Liability [Line Items]
Net foreign exchange losses from re-measurement	$ 2,497	$ 6,132
Selling, General and Administrative Expenses [Member]
Change in Contract with Customer, Liability [Line Items]
Net foreign exchange losses from re-measurement			$ 2,823
Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Change in Contract with Customer, Liability [Line Items]
Number of customers comprising of Accounts Receivable \| Customer	1
Customer Concentration Risk [Member] \| Customer A [Member] \| Sales Revenue, Net [Member]
Change in Contract with Customer, Liability [Line Items]
Concentration risk, percentage	12.00%	13.00%	14.00%
Customer Concentration Risk [Member] \| Customer B [Member] \| Sales Revenue, Net [Member]
Change in Contract with Customer, Liability [Line Items]
Concentration risk, percentage	11.00%	12.00%	11.00%
Customer Concentration Risk [Member] \| Semiconductor Products [Member] \| Sales Revenue, Net [Member]
Change in Contract with Customer, Liability [Line Items]
Concentration risk, percentage	55.00%	57.00%	56.00%
Minimum [Member]
Change in Contract with Customer, Liability [Line Items]
Intangible assets amortized period	1 year
Minimum [Member] \| Accounting Standards Codification Topic 606 adjustment [Member]
Change in Contract with Customer, Liability [Line Items]
Company's normal payment terms	30 days
Warranty period	12 months
Term of separately priced contracts	12 months
Minimum [Member] \| Credit Concentration Risk [Member] \| Accounts Receivable [Member]
Change in Contract with Customer, Liability [Line Items]
Concentration risk, percentage	10.00%	10.00%
Minimum [Member] \| Buildings [Member]
Change in Contract with Customer, Liability [Line Items]
Estimated useful lives	10 years
Minimum [Member] \| Machinery and Equipment [Member]
Change in Contract with Customer, Liability [Line Items]
Estimated useful lives	3 years
Minimum [Member] \| Furniture and Fixtures [Member]
Change in Contract with Customer, Liability [Line Items]
Estimated useful lives	3 years
Minimum [Member] \| Office Equipment [Member]
Change in Contract with Customer, Liability [Line Items]
Estimated useful lives	3 years
Maximum [Member]
Change in Contract with Customer, Liability [Line Items]
Intangible assets amortized period	18 years
Maximum [Member] \| Accounting Standards Codification Topic 606 adjustment [Member]
Change in Contract with Customer, Liability [Line Items]
Term of installation services	14 days
Company's normal payment terms	60 days
Warranty period	24 months
Term of separately priced contracts	60 months
Maximum [Member] \| Buildings [Member]
Change in Contract with Customer, Liability [Line Items]
Estimated useful lives	50 years
Maximum [Member] \| Machinery and Equipment [Member]
Change in Contract with Customer, Liability [Line Items]
Estimated useful lives	16 years
Maximum [Member] \| Furniture and Fixtures [Member]
Change in Contract with Customer, Liability [Line Items]
Estimated useful lives	16 years
Maximum [Member] \| Office Equipment [Member]
Change in Contract with Customer, Liability [Line Items]
Estimated useful lives	16 years