Investments (Details) (USD $) In Thousands, unless otherwise specified	Mar. 29, 2014	Dec. 28, 2013
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	$ 1,309,410	$ 1,287,802
Gross Unrealized Gains	867	715
Gross Unrealized Losses	(361)	(367)
Fair Value	1,309,916	1,288,150
Cash equivalents [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	74,574	68,435
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value	74,574	68,435
Cash equivalents [Member] | Money market funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	61,473	57,254
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value	61,473	57,254
Cash equivalents [Member] | Time deposits [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	11,471	7,771
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value	11,471	7,771
Cash equivalents [Member] | Commercial paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost		3,000
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value		3,000
Cash equivalents [Member] | Government and corporate bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	1,630	410
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value	1,630	410
Short-term investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	810,949	676,723
Gross Unrealized Gains	532	369
Gross Unrealized Losses	(154)	(88)
Fair Value	811,327	677,004
Short-term investments [Member] | Time deposits [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	71,521	70,303
Gross Unrealized Gains	4	12
Gross Unrealized Losses	(2)
Fair Value	71,523	70,315
Short-term investments [Member] | Commercial paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	28,500	33,750
Gross Unrealized Gains	9	1
Gross Unrealized Losses	(1)	(9)
Fair Value	28,508	33,742
Short-term investments [Member] | Government and corporate bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	710,928	572,670
Gross Unrealized Gains	519	356
Gross Unrealized Losses	(151)	(79)
Fair Value	711,296	572,947
Long-term investments [Member] | Government and corporate bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	423,887	542,644
Gross Unrealized Gains	335	346
Gross Unrealized Losses	(207)	(279)
Fair Value	$ 424,015	$ 542,711