Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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

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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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The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

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Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail) (USD $)	3 Months Ended
	Apr. 05, 2015	Dec. 31, 2014
Assets:
Money market instruments	$ 1,240,000us-gaap_MoneyMarketFundsAtCarryingValue	$ 777,000us-gaap_MoneyMarketFundsAtCarryingValue
Financial assets at fair value	510,820,000
Corporate Bonds
Assets:
Financial assets at fair value	241,634,000
Treasury Bills
Assets:
Financial assets at fair value	96,168,000
Asset-Backed Securities
Assets:
Financial assets at fair value	77,840,000
Euro liquidity fund
Assets:
Financial assets at fair value	62,045,000
Agency Bonds
Assets:
Financial assets at fair value	12,887,000
Sovereign Bonds
Assets:
Financial assets at fair value	11,645,000
Municipal Bonds
Assets:
Financial assets at fair value	6,699,000
Supranational bonds
Assets:
Financial assets at fair value	1,902,000
Fair Value, Measurements, Nonrecurring
Liabilities:
Asset Impairment Charges	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets:
Money market instruments	1,240,000
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets:
Money market instruments	0
Assets, Cash flow hedge forward contracts	327,000
Assets, Economic hedge forward contracts	7,000
Liabilities:
Liabilities, Cash flow hedge forward contracts	762,000
Liabilities, Economic hedge forward contracts	17,000
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	0
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Corporate Bonds
Assets:
Financial assets at fair value	241,634,000
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Treasury Bills
Assets:
Financial assets at fair value	96,168,000
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Asset-Backed Securities
Assets:
Financial assets at fair value	77,840,000
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Euro liquidity fund
Assets:
Financial assets at fair value	62,045,000
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Agency Bonds
Assets:
Financial assets at fair value	12,887,000
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Sovereign Bonds
Assets:
Financial assets at fair value	11,645,000
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Municipal Bonds
Assets:
Financial assets at fair value	6,699,000
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Supranational bonds
Assets:
Financial assets at fair value	1,902,000
Fair Value, Inputs, Level 3 \| Fair Value, Measurements, Nonrecurring
Liabilities:
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	$ 0