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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	Jul. 03, 2016	Dec. 31, 2015
Assets:
Money market instruments	$ 7,178	$ 6,024
Financial assets at fair value	601,354
Corporate Bonds
Assets:
Financial assets at fair value	248,922
Treasury Bills
Assets:
Financial assets at fair value	110,979
Asset-Backed Securities
Assets:
Financial assets at fair value	105,185
Euro Liquidity Fund
Assets:
Financial assets at fair value	48,941
Agency Bonds
Assets:
Financial assets at fair value	31,781
Sovereign Bonds
Assets:
Financial assets at fair value	48,181
Municipal Bonds
Assets:
Financial assets at fair value	7,365
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets:
Money market instruments	7,178
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets:
Money market instruments	0
Cash flow hedge forward contracts	205
Liabilities:
Cash flow hedge forward contracts	757
Economic hedge forward contracts	26
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Corporate Bonds
Assets:
Financial assets at fair value	248,922
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Treasury Bills
Assets:
Financial assets at fair value	110,979
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Asset-Backed Securities
Assets:
Financial assets at fair value	105,185
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Euro Liquidity Fund
Assets:
Financial assets at fair value	48,941
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Agency Bonds
Assets:
Financial assets at fair value	31,781
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Sovereign Bonds
Assets:
Financial assets at fair value	48,181
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Municipal Bonds
Assets:
Financial assets at fair value	7,365
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring
Liabilities:
Contingent consideration liability	$ 2,200