Investments (Details) (USD $) In Thousands, unless otherwise specified	Dec. 28, 2013	Dec. 29, 2012
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	$ 1,287,802	$ 1,314,641
Gross Unrealized Gains	715	863
Gross Unrealized Losses	(367)	(537)
Fair Value	1,288,150	1,314,967
Cash equivalents [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	68,435	92,335
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value	68,435	92,335
Cash equivalents [Member] | Money market funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	57,254	68,267
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value	57,254	68,267
Cash equivalents [Member] | Time deposits [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	7,771	24,068
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value	7,771	24,068
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	410
Gross Unrealized Gains
Gross Unrealized Losses
Fair Value	410
Short-term investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	676,723	719,271
Gross Unrealized Gains	369	529
Gross Unrealized Losses	(88)	(135)
Fair Value	677,004	719,665
Short-term investments [Member] | Time deposits [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	70,303	90,535
Gross Unrealized Gains	12	17
Gross Unrealized Losses		(2)
Fair Value	70,315	90,550
Short-term investments [Member] | Commercial paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	33,750	86,500
Gross Unrealized Gains	1	15
Gross Unrealized Losses	(9)	(57)
Fair Value	33,742	86,458
Short-term investments [Member] | Government and corporate bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	572,670	542,236
Gross Unrealized Gains	356	497
Gross Unrealized Losses	(79)	(76)
Fair Value	572,947	542,657
Long-term investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost		503,035
Gross Unrealized Gains		334
Gross Unrealized Losses		(402)
Fair Value		502,967
Long-term investments [Member] | Time deposits [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost		6,190
Gross Unrealized Gains		10
Gross Unrealized Losses		(3)
Fair Value		6,197
Long-term investments [Member] | Government and corporate bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Adjusted Cost	542,644	496,845
Gross Unrealized Gains	346	324
Gross Unrealized Losses	(279)	(399)
Fair Value	$ 542,711	$ 496,770