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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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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. 02, 2017	Dec. 31, 2016
Assets:
Money market instruments	$ 3,895	$ 2,334
Financial assets at fair value	688,877
Corporate Bonds
Assets:
Financial assets at fair value	323,635
Treasury Bills
Assets:
Financial assets at fair value	146,253
Asset-Backed Securities
Assets:
Financial assets at fair value	101,696
Euro Liquidity Fund
Assets:
Financial assets at fair value	73,868
Sovereign Bonds
Assets:
Financial assets at fair value	30,917
Agency Bonds
Assets:
Financial assets at fair value	10,348
Municipal Bonds
Assets:
Financial assets at fair value	2,160
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets:
Money market instruments	3,895
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets:
Money market instruments	0
Cash flow hedge forward contracts	25
Economic hedge forward contracts	7
Liabilities:
Cash flow hedge forward contracts	(13)
Economic hedge forward contracts	(41)
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Corporate Bonds
Assets:
Financial assets at fair value	323,635
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Treasury Bills
Assets:
Financial assets at fair value	146,253
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Asset-Backed Securities
Assets:
Financial assets at fair value	101,696
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Euro Liquidity Fund
Assets:
Financial assets at fair value	73,868
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Sovereign Bonds
Assets:
Financial assets at fair value	30,917
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Agency Bonds
Assets:
Financial assets at fair value	10,348
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Municipal Bonds
Assets:
Financial assets at fair value	2,160
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring
Liabilities:
Contingent consideration liabilities	$ (3,870)