CASH EQUIVALENTS, MARKETABLE SECURITIES AND LONG-TERM INVESTMENTS (Details 2) (USD $) In Thousands, unless otherwise specified	Sep. 28, 2012	Dec. 31, 2011
Cash and cash equivalents, Marketable securities and Investments
Cash equivalents, fair value	$ 45,009	$ 63,105
Marketable securities, fair value	206,614	224,090
Investments, fair value	24,058	55,427
Total carrying value
Cash and cash equivalents, Marketable securities and Investments
Cash equivalents, fair value	45,009	63,105
Marketable securities, fair value	206,614	224,090
Investments, fair value	24,058	55,427
Quoted prices in active markets (Level 1)
Cash and cash equivalents, Marketable securities and Investments
Cash equivalents, fair value	45,009	63,105
Significant other observable inputs (Level 2)
Cash and cash equivalents, Marketable securities and Investments
Marketable securities, fair value	206,614	224,090
Investments, fair value	24,058	55,427
U.S. government agency notes | Total carrying value
Cash and cash equivalents, Marketable securities and Investments
Marketable securities, fair value	66,730	106,727
Investments, fair value	16,636	44,130
U.S. government agency notes | Significant other observable inputs (Level 2)
Cash and cash equivalents, Marketable securities and Investments
Marketable securities, fair value	66,730	106,727
Investments, fair value	16,636	44,130
Foreign government notes | Total carrying value
Cash and cash equivalents, Marketable securities and Investments
Marketable securities, fair value	3,755	1,771
Foreign government notes | Significant other observable inputs (Level 2)
Cash and cash equivalents, Marketable securities and Investments
Marketable securities, fair value	3,755	1,771
Corporate debt securities | Total carrying value
Cash and cash equivalents, Marketable securities and Investments
Marketable securities, fair value	113,571	73,250
Investments, fair value	6,401	11,297
Corporate debt securities | Significant other observable inputs (Level 2)
Cash and cash equivalents, Marketable securities and Investments
Marketable securities, fair value	113,571	73,250
Investments, fair value	6,401	11,297
Commercial paper | Total carrying value
Cash and cash equivalents, Marketable securities and Investments
Marketable securities, fair value	5,494	22,787
Commercial paper | Significant other observable inputs (Level 2)
Cash and cash equivalents, Marketable securities and Investments
Marketable securities, fair value	5,494	22,787
Certificates of deposit | Total carrying value
Cash and cash equivalents, Marketable securities and Investments
Marketable securities, fair value	17,064	19,555
Certificates of deposit | Significant other observable inputs (Level 2)
Cash and cash equivalents, Marketable securities and Investments
Marketable securities, fair value	17,064	19,555
Asset-backed securities | Total carrying value
Cash and cash equivalents, Marketable securities and Investments
Investments, fair value	1,021
Asset-backed securities | Significant other observable inputs (Level 2)
Cash and cash equivalents, Marketable securities and Investments
Investments, fair value	$ 1,021