Organization and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Organization And Summary Of Significant Accounting Policies [Line Items]
Share-based compensation	$ 25.1	$ 15.9
Accumulated deficit	574.6		$ 555.4
Cash, cash equivalents and short-term investments	106.5
Working capital	163.3
Unrecognized compensation cost	$ 216.6
Sales Return Coverage Period	30 days
Computer Equipment [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Machinery and Equipment [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	4 years
Furniture and Fixtures [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	5 years
G4 PLATINUM with Share [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Inventory Write-down		$ 2.0