FAIR VALUE - Financial Assets Measured at Fair Value on Recurring Basis (Detail) (Recurring Basis [Member], USD $) In Thousands, unless otherwise specified	Sep. 28, 2012	Dec. 31, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	$ 150,370	$ 133,358
Total liabilities measured and recorded at fair value	496	159
Cash equivalents [Member] | Money market funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	61,481	62,131
Short-term investments [Member] | State, municipal and local government agencies bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	47,730	38,825
Short-term investments [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	27,026	18,604
Short-term investments [Member] | Commercial paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	10,388	4,195
Short-term investments [Member] | U.S. federal government bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	2,002	9,230
Short-term investments [Member] | Certificates of deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	1,601
Prepaids and other current assets [Member] | Foreign exchange forward contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	142	373
Accrued liabilities [Member] | Foreign exchange forward contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total liabilities measured and recorded at fair value	496	159
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	63,483	71,361
Total liabilities measured and recorded at fair value
Level 1 [Member] | Cash equivalents [Member] | Money market funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	61,481	62,131
Level 1 [Member] | Short-term investments [Member] | U.S. federal government bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	2,002	9,230
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	86,887	61,997
Total liabilities measured and recorded at fair value	496	159
Level 2 [Member] | Short-term investments [Member] | State, municipal and local government agencies bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	47,730	38,825
Level 2 [Member] | Short-term investments [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	27,026	18,604
Level 2 [Member] | Short-term investments [Member] | Commercial paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	10,388	4,195
Level 2 [Member] | Short-term investments [Member] | Certificates of deposit [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	1,601
Level 2 [Member] | Prepaids and other current assets [Member] | Foreign exchange forward contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured and recorded at fair value	142	373
Level 2 [Member] | Accrued liabilities [Member] | Foreign exchange forward contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total liabilities measured and recorded at fair value	$ 496	$ 159