Segment Information (Revenue by Geographic Region) (Detail) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014		Jun. 30, 2015	Jun. 30, 2014
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 33,954	$ 40,825	[1]	$ 64,551	$ 86,549
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	12,303	15,092		24,652	35,520
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	3,728	6,968		7,891	15,380
Republic of Korea
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	12,375	11,092		18,699	21,386
Rest of the World
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 5,548	$ 7,673		$ 13,309	$ 14,263

[1] Quarters ended June 30, 2015 quarter ended June 30, 2015Components of Revenue License Fees6,921 6,664Service Revenue27,033 34,161Net Revenue33,954 40,825 6 months ended June 30, 2015 June 30, 2014Components of Revenue License Fees$14,210 $15,243Service Revenue50,341 71,306Net Revenue$64,551 $86,549