Summary of Significant Accounting Policies - Additional Information (Detail) shares in Millions	12 Months Ended
	Dec. 31, 2015 USD ($) Customer Segment	Dec. 31, 2014 USD ($) Customer	Dec. 31, 2013 USD ($)	Nov. 30, 2010 shares	Aug. 31, 2009 shares
Summary Of Significant Accounting Policies [Line Items]
Deferred revenue-current	$ 554,000	$ 376,000
Long-term deferred revenue	$ 100,000	$ 100,000
Number of major customers representing outstanding trade receivables | Customer	3	1
Life of inventory	2 years
Protracted length of inventory	1 year
Inventory valuation reserves	$ 1,800,000	$ 100,000
Estimated useful life of intangible assets	10 years
Number of reportable segments | Segment	1
Impairment charges on long-lived assets	$ 0	0	$ 0
Period of warranty	1 year
Warranty claim liability	$ 0	0
2009 Warrants
Summary Of Significant Accounting Policies [Line Items]
Warrants to purchase an aggregate shares of common stock | shares					2.4
2010 Warrants
Summary Of Significant Accounting Policies [Line Items]
Warrants to purchase an aggregate shares of common stock | shares				3.7
Computer Software, Intangible Asset
Summary Of Significant Accounting Policies [Line Items]
Capitalized costs for enhancement of enterprise resource planning software system and other internal use software, addition	0	1,800,000
Capitalized costs for enhancement of enterprise resource planning software system and other internal use software	$ 1,300,000	$ 1,600,000
Enterprise resource planning system, estimated useful life	5 years
Trade Accounts Receivable | Customer Concentration Risk
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage	49.00%	36.00%
Minimum
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life of property and equipment	3 years
Maximum
Summary Of Significant Accounting Policies [Line Items]
Estimated useful life of property and equipment	5 years