Acquisitions - Additional Information (Detail) (USD $)	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Acquired Finite-Lived Intangible Assets [Line Items]
Cash consideration	$ 4,533,000	$ 44,533,000
Contingent consideration, current	21,200,000
Contingent consideration, noncurrent	8,400,000
Minimum [Member] | Earnout [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Fair value discount rate	4.20%
Maximum [Member] | Earnout [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Fair value discount rate	6.40%
JJF Enterprises and GamSys [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Cash consideration	3,600,000
Fair value of earnouts	3,000,000
Contingent consideration, current	1,400,000
Contingent consideration, noncurrent	$ 1,600,000
JJF Enterprises and GamSys [Member] | In Process Research And Developments [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Fair value discount rate	17.00%
JJF Enterprises and GamSys [Member] | Minimum [Member] | Acquired Intangible Assets [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Fair value discount rate	16.50%
JJF Enterprises and GamSys [Member] | Minimum [Member] | In Process Research And Developments [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
IPR&D percent complete at acquisition date	50.00%
JJF Enterprises and GamSys [Member] | Minimum [Member] | Earnout [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Fair value discount rate	4.50%
JJF Enterprises and GamSys [Member] | Maximum [Member] | Acquired Intangible Assets [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Fair value discount rate	24.00%
JJF Enterprises and GamSys [Member] | Maximum [Member] | In Process Research And Developments [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
IPR&D percent complete at acquisition date	53.00%
JJF Enterprises and GamSys [Member] | Maximum [Member] | Earnout [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Fair value discount rate	6.00%