Investments and Fair Value Measurements-Cash and Mkt Securities (Details 1) - USD ($) $ in Thousands	Sep. 27, 2015	Dec. 28, 2014	Sep. 28, 2014	Dec. 29, 2013
Cash, Cash Equivalents and Marketable Securities [Abstract]
Cash and Cash Equivalents	$ 698,073	$ 809,003	$ 930,835	$ 986,246
Short-term marketable securities	1,000,621	1,455,509
Long-term marketable securities	2,176,095	2,758,475
Total cash, cash equivalents and marketable securities	$ 3,874,789	$ 5,022,987