Organization and Summary of Significant Accounting Policies - Additional Information (Detail) shares in Millions	12 Months Ended
Dec. 31, 2015 USD ($) Customer Reporting_Unit shares	Dec. 31, 2014 USD ($) Customer shares	Dec. 31, 2013 shares
Organization And Summary Of Significant Accounting Policies [Line Items]
Cash and investments in marketable securities	$ 308,944,000	$ 262,824,000
Senior secured notes	250,000,000
Debt and capital lease obligation	255,800,000
Capital lease obligations	5,800,000
Capital lease obligations, current portion	$ 4,756,000	$ 4,512,000
Number of customers accounted for major accounts receivable \| Customer	3	3
Percentage of accounts receivable customers one	50.00%	40.00%
Percentage of accounts receivable customers two	35.00%	31.00%
Percentage of accounts receivable customers three	10.00%	15.00%
Number of reporting unit evaluated for goodwill \| Reporting_Unit	1
Asset impairment charges	$ 0
Minimum percentage of amount realized upon ultimate settlement	50.00%
Stock Options and Restricted Stock Units [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Weighted average diluted securities excluded from diluted net loss per share \| shares	21.1	21.9	20.7
Minimum [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Property and equipment estimated useful lives	3 years
Maximum [Member]
Organization And Summary Of Significant Accounting Policies [Line Items]
Property and equipment estimated useful lives	10 years

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