Fair Value Measurements (Details) (USD $)	Sep. 29, 2012	Dec. 31, 2011	Sep. 29, 2012 Fair Value, Measurements, Recurring Total	Oct. 01, 2011 Fair Value, Measurements, Recurring Total	Sep. 29, 2012 Fair Value, Measurements, Recurring Quoted Prices in Active Markets for Identical Assets (Level 1)	Oct. 01, 2011 Fair Value, Measurements, Recurring Quoted Prices in Active Markets for Identical Assets (Level 1)	Sep. 29, 2012 Fair Value, Measurements, Recurring Significant Other Observable Inputs, (Level 2)	Oct. 01, 2011 Fair Value, Measurements, Recurring Significant Other Observable Inputs, (Level 2)	Sep. 29, 2012 Fair Value, Measurements, Recurring Significant Unobservable Inputs (Level 3)	Oct. 01, 2011 Fair Value, Measurements, Recurring Significant Unobservable Inputs (Level 3)	Sep. 29, 2012 Commercial papers	Dec. 31, 2011 Commercial papers	Sep. 29, 2012 Money market funds	Dec. 31, 2011 Money market funds	Sep. 29, 2012 U.S. corporate debt securities	Dec. 31, 2011 U.S. corporate debt securities	Sep. 29, 2012 U.S. treasury bills and notes	Dec. 31, 2011 U.S. treasury bills and notes	Sep. 29, 2012 Securities and obligations of U.S. government agencies	Dec. 31, 2011 Securities and obligations of U.S. government agencies	Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments Available-for-sale securities Fair Value, Measurements, Recurring Total		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments Available-for-sale securities Fair Value, Measurements, Recurring Total		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments Available-for-sale securities Fair Value, Measurements, Recurring Quoted Prices in Active Markets for Identical Assets (Level 1)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments Available-for-sale securities Fair Value, Measurements, Recurring Quoted Prices in Active Markets for Identical Assets (Level 1)		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments Available-for-sale securities Fair Value, Measurements, Recurring Significant Other Observable Inputs, (Level 2)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments Available-for-sale securities Fair Value, Measurements, Recurring Significant Other Observable Inputs, (Level 2)		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments Available-for-sale securities Fair Value, Measurements, Recurring Significant Unobservable Inputs (Level 3)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments Available-for-sale securities Fair Value, Measurements, Recurring Significant Unobservable Inputs (Level 3)		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments Commercial papers Fair Value, Measurements, Recurring Total		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments Commercial papers Fair Value, Measurements, Recurring Total		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments Commercial papers Fair Value, Measurements, Recurring Quoted Prices in Active Markets for Identical Assets (Level 1)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments Commercial papers Fair Value, Measurements, Recurring Quoted Prices in Active Markets for Identical Assets (Level 1)		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments Commercial papers Fair Value, Measurements, Recurring Significant Other Observable Inputs, (Level 2)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments Commercial papers Fair Value, Measurements, Recurring Significant Other Observable Inputs, (Level 2)		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments Commercial papers Fair Value, Measurements, Recurring Significant Unobservable Inputs (Level 3)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments Commercial papers Fair Value, Measurements, Recurring Significant Unobservable Inputs (Level 3)		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments Money market funds Fair Value, Measurements, Recurring Total		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments Money market funds Fair Value, Measurements, Recurring Total		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments Money market funds Fair Value, Measurements, Recurring Quoted Prices in Active Markets for Identical Assets (Level 1)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments Money market funds Fair Value, Measurements, Recurring Quoted Prices in Active Markets for Identical Assets (Level 1)		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments Money market funds Fair Value, Measurements, Recurring Significant Other Observable Inputs, (Level 2)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments Money market funds Fair Value, Measurements, Recurring Significant Other Observable Inputs, (Level 2)		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments Money market funds Fair Value, Measurements, Recurring Significant Unobservable Inputs (Level 3)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments Money market funds Fair Value, Measurements, Recurring Significant Unobservable Inputs (Level 3)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments U.S. corporate debt securities Fair Value, Measurements, Recurring Total		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments U.S. corporate debt securities Fair Value, Measurements, Recurring Quoted Prices in Active Markets for Identical Assets (Level 1)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments U.S. corporate debt securities Fair Value, Measurements, Recurring Significant Other Observable Inputs, (Level 2)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments U.S. corporate debt securities Fair Value, Measurements, Recurring Significant Unobservable Inputs (Level 3)		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments U.S. treasury bills and notes Fair Value, Measurements, Recurring Total		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments U.S. treasury bills and notes Fair Value, Measurements, Recurring Total		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments U.S. treasury bills and notes Fair Value, Measurements, Recurring Quoted Prices in Active Markets for Identical Assets (Level 1)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments U.S. treasury bills and notes Fair Value, Measurements, Recurring Quoted Prices in Active Markets for Identical Assets (Level 1)		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments U.S. treasury bills and notes Fair Value, Measurements, Recurring Significant Other Observable Inputs, (Level 2)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments U.S. treasury bills and notes Fair Value, Measurements, Recurring Significant Other Observable Inputs, (Level 2)		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments U.S. treasury bills and notes Fair Value, Measurements, Recurring Significant Unobservable Inputs (Level 3)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments U.S. treasury bills and notes Fair Value, Measurements, Recurring Significant Unobservable Inputs (Level 3)		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments Securities and obligations of U.S. government agencies Fair Value, Measurements, Recurring Total		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments Securities and obligations of U.S. government agencies Fair Value, Measurements, Recurring Total		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments Securities and obligations of U.S. government agencies Fair Value, Measurements, Recurring Quoted Prices in Active Markets for Identical Assets (Level 1)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments Securities and obligations of U.S. government agencies Fair Value, Measurements, Recurring Quoted Prices in Active Markets for Identical Assets (Level 1)		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments Securities and obligations of U.S. government agencies Fair Value, Measurements, Recurring Significant Other Observable Inputs, (Level 2)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments Securities and obligations of U.S. government agencies Fair Value, Measurements, Recurring Significant Other Observable Inputs, (Level 2)		Sep. 29, 2012 Cash and Cash Equivalents and Short-term Investments Securities and obligations of U.S. government agencies Fair Value, Measurements, Recurring Significant Unobservable Inputs (Level 3)		Oct. 01, 2011 Cash and Cash Equivalents and Short-term Investments Securities and obligations of U.S. government agencies Fair Value, Measurements, Recurring Significant Unobservable Inputs (Level 3)		Sep. 29, 2012 Designated as Hedging Instrument Foreign Exchange Forward Fair Value, Measurements, Recurring Total		Oct. 01, 2011 Designated as Hedging Instrument Foreign Exchange Forward Fair Value, Measurements, Recurring Total		Sep. 29, 2012 Designated as Hedging Instrument Foreign Exchange Forward Fair Value, Measurements, Recurring Quoted Prices in Active Markets for Identical Assets (Level 1)		Oct. 01, 2011 Designated as Hedging Instrument Foreign Exchange Forward Fair Value, Measurements, Recurring Quoted Prices in Active Markets for Identical Assets (Level 1)		Sep. 29, 2012 Designated as Hedging Instrument Foreign Exchange Forward Fair Value, Measurements, Recurring Significant Other Observable Inputs, (Level 2)		Oct. 01, 2011 Designated as Hedging Instrument Foreign Exchange Forward Fair Value, Measurements, Recurring Significant Other Observable Inputs, (Level 2)		Sep. 29, 2012 Designated as Hedging Instrument Foreign Exchange Forward Fair Value, Measurements, Recurring Significant Unobservable Inputs (Level 3)		Oct. 01, 2011 Designated as Hedging Instrument Foreign Exchange Forward Fair Value, Measurements, Recurring Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total, fair value	$ 225,888,000	$ 184,724,000									$ 17,997,000	$ 9,996,000	$ 5,318,000	$ 6,706,000	$ 0	$ 1,440,000	$ 4,026,000	$ 3,913,000	$ 198,547,000	$ 162,669,000	$ 225,888,000	[1]	$ 184,724,000	[1]	$ 5,318,000	[1]	$ 6,706,000	[1]	$ 220,570,000	[1]	$ 178,018,000	[1]	$ 0	[1]	$ 0	[1]	$ 17,997,000	[1]	$ 9,996,000	[1]	$ 0	[1]	$ 0	[1]	$ 17,997,000	[1]	$ 9,996,000	[1]	$ 0	[1]	$ 0	[1]	$ 5,318,000	[1]	$ 6,706,000	[1]	$ 5,318,000	[1]	$ 6,706,000	[1]	$ 0	[1]	$ 0	[1]	$ 0	[1]	$ 0	[1]	$ 1,440,000	[1]	$ 0	[1]	$ 1,440,000	[1]	$ 0	[1]	$ 4,026,000	[1]	$ 3,913,000	[1]	$ 0	[1]	$ 0	[1]	$ 4,026,000	[1]	$ 3,913,000	[1]	$ 0	[1]	$ 0	[1]	$ 198,547,000	[1]	$ 162,669,000	[1]	$ 0	[1]	$ 0	[1]	$ 198,547,000	[1]	$ 162,669,000	[1]	$ 0	[1]	$ 0	[1]
Foreign currency derivatives, other current asset																																																																																																													8,000	[2]	3,000	[2]	0	[2]	0	[2]	8,000	[2]	3,000	[2]	0	[2]	0	[2]
Foreign currency derivatives, other current liabilities																																																																																																													(19,000)	[3]	(1,000)	[3]	0	[3]	0	[3]	(19,000)	[3]	(1,000)	[3]	0	[3]	0	[3]
Net current assets and current liabilities, fair value			$ 225,877,000	$ 184,726,000	$ 5,318,000	$ 6,706,000	$ 220,559,000	$ 178,020,000	$ 0	$ 0

[1] (1)Included in cash and cash equivalents and short-term investments on our condensed consolidated balance sheet. See “Investments” in Note 6 for further details.

[2] (2)Included in other current assets on our condensed consolidated balance sheet. Consisted of forward foreign exchange contracts for the Japanese yen. See “Derivative Instruments and Hedging” in Note 7 for further details.

[3] (3)Included in other current liabilities on our condensed consolidated balance sheet. Consisted of forward foreign exchange contracts for the Japanese yen. See “Derivative Instruments and Hedging” in Note 7 for further details.