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Amount of debt securities categorized neither as held-to-maturity nor trading.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Fair value as of the balance sheet date of all foreign currency derivative assets designated as cash flow hedging instruments.

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Fair value as of the balance sheet date of all foreign currency derivative liabilities designated as cash flow hedging instruments.

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Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

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Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail) - USD ($) $ in Thousands	Apr. 03, 2016	Dec. 31, 2015
Assets:
Money market instruments	$ 31,311	$ 6,024
Financial assets at fair value	568,607
Corporate Bonds
Assets:
Financial assets at fair value	233,848
Treasury Bills
Assets:
Financial assets at fair value	149,540
Asset-Backed Securities
Assets:
Financial assets at fair value	91,593
Euro Liquidity Fund
Assets:
Financial assets at fair value	50,094
Agency Bonds
Assets:
Financial assets at fair value	9,175
Sovereign Bonds
Assets:
Financial assets at fair value	29,489
Municipal Bonds
Assets:
Financial assets at fair value	4,868
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets:
Money market instruments	31,311
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets:
Money market instruments	0
Cash flow hedge forward contracts	16
Liabilities:
Cash flow hedge forward contracts	460
Foreign Currency Contracts, Liability, Fair Value Disclosure	40
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Corporate Bonds
Assets:
Financial assets at fair value	233,848
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Treasury Bills
Assets:
Financial assets at fair value	149,540
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Asset-Backed Securities
Assets:
Financial assets at fair value	91,593
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Euro Liquidity Fund
Assets:
Financial assets at fair value	50,094
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Agency Bonds
Assets:
Financial assets at fair value	9,175
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Sovereign Bonds
Assets:
Financial assets at fair value	29,489
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Municipal Bonds
Assets:
Financial assets at fair value	4,868
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring
Liabilities:
Business Combination, Contingent Consideration, Liability	$ 2,737