Fair Value Measurement - Additional Information (Detail) (USD $)	12 Months Ended		0 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Aug. 01, 2012 Apache Design Solutions, Inc.	Aug. 01, 2011 Apache Design Solutions, Inc.	Dec. 31, 2012 Significant Unobservable Inputs (Level 3)	Dec. 31, 2011 Significant Unobservable Inputs (Level 3)
Fair Value Measurements [Line Items]
Short-term investment time deposits maturity minimum, in months	3 months
Short-term investment time deposits maturity maximum, in years	1 year
Unrealized gains or losses associated with deposits	$ 0	$ 0
Foreign currency future liability	240,000				0
Contingent consideration arrangement, additional payments				12,000,000
Contingent payments			4,000,000
Deferred compensation liability	1,394,000	2,073,000			1,394,000	2,073,000
Contingent consideration liability				(9,501,000)	6,436,000
Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount	$ 0