Control4 (CTRL) 10-Q 1 Nov 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2013	Oct. 25, 2013
Document and Entity Information	'	'
Entity Registrant Name	'Control4 Corp	'
Entity Central Index Key	'0001259515	'
Document Type	'10-Q	'
Document Period End Date	30-Sep-13	'
Amendment Flag	'false	'
Current Fiscal Year End Date	'--12-31	'
Entity Current Reporting Status	'No	'
Entity Filer Category	'Non-accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	22,772,528
Document Fiscal Year Focus	'2013	'
Document Fiscal Period Focus	'Q3	'

CONDENSED_CONSOLIDATED_BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$82,485	$18,695
Accounts receivable, net	15,941	13,078
Inventories	15,559	12,515
Prepaid expenses and other current assets	1,965	1,871
Total current assets	115,950	46,159
Property and equipment, net	3,640	2,666
Intangible assets, net	970	926
Other assets	1,130	887
Total assets	121,690	50,638
Current liabilities:	'	'
Accounts payable	16,699	14,435
Accrued liabilities	5,548	6,571
Deferred revenue	637	542
Current portion of notes payable	1,191	1,321
Total current liabilities	24,075	22,869
Notes payable	2,127	1,838
Warrant liability	'	601
Other long-term liabilities	484	1,620
Total liabilities	26,686	26,928
Commitments and contingencies	'	'
Redeemable convertible preferred stock, $0.0001 par value; 83,163,408 and no shares authorized; 15,293,960 and no shares issued and outstanding at December 31, 2012 and September 30, 2013 (unaudited), respectively; aggregate liquidation preference of $118,150 and $0 at December 31, 2012 and September 30, 2013 (unaudited), respectively	'	116,313
Stockholders' equity (deficit):	'	'
Preferred stock, $0.0001 par value, no and 25,000,000 shares authorized; no shares issued and outstanding at December 31, 2012 and September 30, 2013 (unaudited), respectively	'	'
Common stock, $0.0001 par value; 127,836,592 and 500,000,000 shares authorized; 2,490,870 and 22,766,644 shares issued and outstanding at December 31, 2012 and September 30, 2013 (unaudited), respectively	2	'
Additional paid-in capital	199,354	12,988
Accumulated deficit	-104,354	-105,587
Accumulated other comprehensive income (loss)	2	-4
Total stockholders' equity (deficit)	95,004	-92,603
Total liabilities, redeemable convertible preferred stock and stockholders' equity (deficit)	$121,690	$50,638

CONDENSED_CONSOLIDATED_BALANCE1

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, except Share data, unless otherwise specified
CONDENSED CONSOLIDATED BALANCE SHEETS	'	'
Redeemable convertible preferred stock, par value (in dollars per share)	$0.00	$0.00
Redeemable convertible preferred stock, shares authorized	0	83,163,408
Redeemable convertible preferred stock, shares issued	0	15,293,960
Redeemable convertible preferred stock, shares outstanding	0	15,293,960
Redeemable convertible preferred stock, aggregate liquidation preference value (in dollars)	$0	$118,150
Preferred stock, par value (in dollars per share)	$0.00	$0.00
Preferred stock, shares authorized	25,000,000	0
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$0.00	$0.00
Common stock, shares authorized	500,000,000	127,836,592
Common stock, shares issued	22,766,644	2,490,870
Common stock, shares outstanding	22,766,644	2,490,870

CONDENSED_CONSOLIDATED_STATEME

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS	'	'	'	'
Revenue	$33,641	$28,605	$92,755	$78,847
Cost of revenue	16,592	14,918	46,129	41,710
Cost of revenue - inventory purchase commitment	'	1,840	-180	1,840
Gross margin	17,049	11,847	46,806	35,297
Operating expenses:	'	'	'	'
Research and development	6,409	5,158	18,670	15,119
Sales and marketing	5,596	5,333	16,597	15,479
General and administrative	2,847	2,471	8,623	7,666
Litigation settlement	200	2,869	440	2,869
Total operating expenses	15,052	15,831	44,330	41,133
Income (loss) from operations	1,997	-3,984	2,476	-5,836
Other income (expense):	'	'	'	'
Interest income	4	2	8	11
Interest expense	-209	-65	-420	-209
Other income (expense)	42	-45	-699	-222
Total other income (expense)	-163	-108	-1,111	-420
Income (loss) before income taxes	1,834	-4,092	1,365	-6,256
Income tax expense	-103	0	-132	0
Net income (loss)	$1,731	($4,092)	$1,233	($6,256)
Net income (loss) per common share:	'	'	'	'
Basic (in dollars per share)	$0.12	($1.73)	$0.19	($2.69)
Diluted (in dollars per share)	$0.07	($1.73)	$0.06	($2.69)
Weighted-average number of shares:	'	'	'	'
Basic (in shares)	14,389	2,363	6,511	2,324
Diluted (in shares)	23,556	2,363	21,206	2,324

CONDENSED_CONSOLIDATED_STATEME1

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS)	'	'	'	'
Net income (loss)	$1,731	($4,092)	$1,233	($6,256)
Other comprehensive income (loss):	'	'	'	'
Foreign currency translation adjustment	12	-7	6	-37
Total other comprehensive income (loss)	12	-7	6	-37
Comprehensive income (loss)	$1,743	($4,099)	$1,239	($6,293)

CONDENSED_CONSOLIDATED_STATEME2

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Operating activities	'	'
Net income (loss)	$1,233	($6,256)
Adjustments to reconcile net income (loss) to net cash (used in) provided by operating activities:	'	'
Depreciation expense	1,609	1,254
Amortization of intangible assets	218	203
Provision for doubtful accounts	112	203
Loss (gain) on inventory purchase commitment	-180	1,840
Stock-based compensation	2,648	2,094
Warrant liability expense	709	222
Changes in assets and liabilities:	'	'
Accounts receivable	-2,978	-3,199
Inventories	-2,947	-1,318
Prepaid expenses and other current assets	-98	-495
Other assets	-243	-783
Accounts payable	2,150	3,964
Accrued liabilities	-838	2,650
Deferred revenue	95	46
Other long-term liabilities	-1,138	-450
Net cash (used in) provided by operating activities	352	-25
Investing activities	'	'
Purchases of property and equipment	-2,575	-1,656
Business acquisition	-88	'
Net cash used in investing activities	-2,663	-1,656
Financing activities	'	'
Proceeds from issuance of common stock, net of issuance costs	65,556	'
Proceeds from exercise of options for common stock	367	191
Proceeds from notes payable	1,145	1,376
Repayment of notes payable	-986	-708
Net cash provided by financing activities	66,082	859
Effect of exchange rate changes on cash and cash equivalents	19	-37
Net increase (decrease) in cash and cash equivalents	63,790	-859
Cash and cash equivalents at beginning of period	18,695	18,468
Cash and cash equivalents at end of period	82,485	17,609
Supplemental disclosure of cash flow information	'	'
Cash paid for interest	419	208
Cash paid for taxes	131	'
Supplemental schedule of non-cash investing and financing activities	'	'
Options for common stock granted in connection with a business acquisition	174	'
Elimination of liability upon net exercise of warrants to purchase preferred stock	1,310	'
Conversion of redeemable convertible preferred stock to common stock	$116,313	'

Description_of_Business_and_Su

Description of Business and Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2013
Description of Business and Summary of Significant Accounting Policies	'
Description of Business and Summary of Significant Accounting Policies	'
	1. Description of Business and Summary of Significant Accounting Policies
	Control4 Corporation (‘‘Control4’’ or the ‘‘Company’’) is a leading provider of automation and control solutions for the connected home. The Company unlocks the potential of connected devices, making entertainment systems easier to use, homes more comfortable, appliances more energy efficient, and families more secure. The Company was incorporated in the state of Delaware on March 27, 2003.
	Reclassifications
	Certain prior-year amounts have been reclassified in order to conform to the current-year presentation. The reclassification is related to gains or losses on inventory purchase commitments from accrued liabilities into the applicable caption on the statements of cash flows. This reclassification had no effect on the previously reported net cash (used in) provided by operating activities.
	Unaudited Interim Financial Statements
	The accompanying condensed consolidated balance sheets and the condensed consolidated statements of operations, comprehensive income (loss), and cash flows are unaudited. These unaudited interim condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (‘‘GAAP’’) on the same basis as the audited consolidated financial statements and, in the opinion of management, reflect all adjustments, consisting of only normal recurring adjustments, considered necessary to present fairly the Company’s financial position, results of operations and cash flows. The results of operations for the three and nine months ended September 30, 2013 are not necessarily indicative of the results that may be expected for the year ending December 31, 2013, or any other future interim or annual period.
	These unaudited interim condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and related notes included in the Company’s Prospectus filed with the Securities and Exchange Commission (the “SEC”) on August 2, 2013. The December 31, 2012 consolidated balance sheet included herein was derived from the audited financial statements as of that date.
	Basis of Presentation
	The unaudited condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated in the unaudited condensed consolidated financial statements.
	Initial Public Offering
	On August 7, 2013, the Company completed its initial public offering (“IPO”) of common stock in which the Company sold and issued 4,600,000 shares of common stock at a price of $16.00 per share. As a result of the IPO, the Company raised a total of $73.6 million in gross proceeds, or approximately $65.6 million in net proceeds after deducting underwriting discounts and commissions of $5.2 million and offering expenses of approximately $2.8 million.
	Stock Split
	In July 2013, the Company’s board of directors and stockholders approved an amendment to the Company’s amended and restated certificate of incorporation. The amendment provided for a 1-for-5.2 reverse stock split of the outstanding common stock and outstanding convertible preferred stock (collectively, “Capital Stock”), which became effective on July 18, 2013. Accordingly, (i) every 5.2 shares of Capital Stock have been combined into one share of Capital Stock, (ii) the number of shares of Capital Stock into which each outstanding option or warrant to purchase Capital Stock is exercisable, as the case may be, have been proportionately decreased on a 5.2-for-1 basis, and (iii) the exercise price for each such outstanding option or warrant to purchase Capital Stock has been proportionately increased on a 1-for-5.2 basis. All of the share numbers, share prices, and exercise prices have been adjusted within these financial statements, on a retroactive basis, to reflect this 1-for-5.2 reverse stock split.
	Segment Reporting
	Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker, the Chief Executive Officer, in making decisions regarding resource allocation and accessing performance. To date, the Company has viewed its operations and manages its business as one segment.
	Concentrations of Risk
	Financial instruments that potentially subject the Company to a concentration of credit risk consist of cash and cash equivalents and accounts receivable. The Company deposits cash and cash equivalents with one high-credit-quality financial institution and maintains balances that exceed federally insured amounts. The Company has policies that limit its investments as to types of investments, maturity, liquidity, credit quality, concentration and diversification of issuers.
	The Company’s accounts receivable are derived from revenue earned from customers primarily located in the United States and Canada. The Company’s sales to customers located outside the United States are generally denominated in United States dollars, except for sales to customers located in the United Kingdom, which are denominated in pounds sterling. There were no individual account balances greater than 10% of total accounts receivable at December 31, 2012 and September 30, 2013.
	No customer accounted for more than 10% of total revenue for the three- and nine-month periods ended September 30, 2012 and 2013.
	The Company relies on a limited number of suppliers for its contract manufacturing. A significant disruption in the operations of these manufacturers would impact the production of the Company’s products for a substantial period of time, which could have a material adverse effect on the Company’s business, financial condition and results of operations.
	Geographic Information
	The Company’s revenue includes amounts earned through sales to customers located outside of the United States. With the exception of Canada, no single foreign country accounted for more than 10% of total revenue for the three- and nine-month periods ended September 30, 2012 and 2013. The following table sets forth revenue from the U.S., Canadian and all other international customers combined (in thousands):
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
		2012			2013			2012			2013
	Revenue-United States	$	17,845		$	22,264		$	51,347		$	61,430
	Revenue-Canada	3,344			3,641			9,184			10,690
	Revenue-all other international sources	7,416			7,736			18,316			20,635
	Total revenue	$	28,605		$	33,641		$	78,847		$	92,755
	International revenue (excluding Canada) as a percent of total revenue	26		%	23		%	23		%	22		%
	Use of Accounting Estimates
	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, the Company evaluates its estimates including those related to revenue recognition, sales returns, provisions for doubtful accounts, product warranty, inventory obsolescence, litigation, determination of fair value of stock options, deferred tax asset valuation allowances and income taxes. Actual results may differ from those estimates.
	Product Warranty
	The Company provides its customers a limited product warranty of two years, which requires the Company to repair or replace defective products during the warranty period at no cost to the customer. The Company estimates the costs that may be incurred to replace or repair defective products and records a reserve at the time revenue is recognized. Factors that affect the Company’s warranty liability include the number of installed systems, the Company’s historical experience and management’s judgment regarding anticipated rates of product warranty returns. The Company assesses the adequacy of its recorded warranty liability each period and makes adjustments to the liability as necessary.
	The following table presents the changes in the product warranty liability (in thousands):
		Warranty Liability
	Balance at December 31, 2012	$	1,155
	Warranty costs accrued	420
	Warranty claims	(414		)
	Balance at September 30, 2013	$	1,161
	Fair Value of Financial Instruments
	The carrying amounts reported in the accompanying condensed consolidated financial statements for cash and cash equivalents, accounts payable and accrued liabilities approximate their fair value because of the short-term nature of the accounts. The fair value of the notes payable approximates its carrying value based on the variable nature of interest rates and current market rates available to the Company.
	Net Income (Loss) Per Share
	Basic net income (loss) per share is computed using the weighted-average number of common shares outstanding during the period. Diluted net income (loss) per share is computed using the weighted-average number of common shares outstanding and potentially dilutive common shares outstanding during the period that have a dilutive effect on net income per share. Potentially dilutive common shares result from the assumed exercise of outstanding stock options and the assumed conversion of outstanding convertible preferred stock and warrants using the if-converted method. In a net loss position, diluted net loss per share is computed using only the weighted-average number of common shares outstanding during the period, as any additional common shares would be anti-dilutive.
	The following table presents the reconciliation of the numerator and denominator used in the calculation of basic and diluted net income (loss) per share (in thousands):
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
		2012			2013			2012			2013
	Numerator:
	Net income (loss)	$	(4,092	)	$	1,731		$	(6,256	)	$	1,233
	Denominator:
	Weighted average common stock outstanding for basic net income (loss) per common share	2,363			14,389			2,324			6,511
	Effect of dilutive securities—stock options, convertible preferred stock, and warrants to purchase common stock and preferred stock	—			9,167			—			14,695
	Weighted average common shares and dilutive securities outstanding	2,363			23,556			2,324			21,206
	The following weighted-average common stock equivalents were anti-dilutive and therefore were excluded from the calculation of diluted net income (loss) per share (in thousands):
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
		2012		2013		2012		2013
	Convertible preferred stock	15,294		—		15,294		—
	Options to purchase common stock	4,366		253		4,312		355
	Warrants to purchase common stock	541		—		541		—
	Warrants to purchase preferred stock	194		—		194		1
	Total	20,395		253		20,341		356
Recent Accounting Pronouncements
In February 2013, the FASB issued ASU 2013-02, ‘‘Comprehensive Income: Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income.’’ The amended guidance requires an entity to present the effects on the line items of net income of significant reclassifications out of accumulated other comprehensive income if the amount being reclassified is required under U.S. generally accepted accounting principles to be reclassified in its entirety to net income in the same reporting period. The guidance is effective prospectively for the reporting periods beginning after December 15, 2012. This new guidance was effective for the Company beginning January 1, 2013. The adoption of this guidance did not have an impact on the Company’s results of operations, financial position, or cash flows as it relates only to financial statement presentation.

Balance_Sheet_Components

Balance Sheet Components	9 Months Ended
	Sep. 30, 2013
Balance Sheet Components	'
Balance Sheet Components	'
	2. Balance Sheet Components
	Inventories consisted of the following (in thousands):
		December 31,			September 30,
		2012			2013
	Finished goods	$	12,306		$	14,202
	Component parts	209			1,357
		$	12,515		$	15,559
	Property and equipment, net consisted of the following (in thousands):
		December 31,			September 30,
		2012			2013
	Computer equipment and software	$	3,518		$	3,817
	Manufacturing tooling and test equipment	2,731			2,647
	Furniture and fixtures	1,801			1,965
	Lab and warehouse equipment	1,974			2,311
	Marketing equipment	419			424
	Leasehold improvements	803			1,390
		11,246			12,554
	Less: accumulated depreciation	(8,580		)	(8,914		)
		$	2,666		$	3,640
	Intangible assets, net consisted of the following (in thousands):
		December 31,			September 30,
		2012			2013
	Acquired technology	$	1,357		$	1,628
	Less: accumulated amortization	(431		)	(658		)
		$	926		$	970
	Other assets consisted of the following (in thousands):
		December 31,			September 30,
		2012			2013
	Prepaid licensing	700			735
	Deposits	187			395
		$	887		$	1,130
	Accrued liabilities consisted of the following (in thousands):
		December 31,			September 30,
		2012			2013
	Current portion of settlement obligations (see Note 5)	$	2,229		$	887
	Sales returns and warranty accruals	2,045			2,104
	Compensation accruals	1,495			2,118
	Other accrued liabilities	802			439
		$	6,571		$	5,548

Fair_Value_Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2013
Fair Value Measurements	'
Fair Value Measurements	'
	3. Fair Value Measurements
	The Company’s financial instruments that are measured at fair value on a recurring basis consist of money market funds and redeemable preferred stock warrants. The following three levels of inputs are used to measure the fair value of financial instruments:
	Level 1: Quoted prices in active markets for identical assets or liabilities. The Company classifies its money market funds as Level 1 instruments as they are traded in active markets with sufficient volume and frequency of transactions.
	Level 2: Observable prices that are based on inputs not quoted on active markets, but corroborated by market data. The Company did not have any Level 2 instruments during the reported periods.
	Level 3: Unobservable inputs are used when little or no market data is available. The Company utilized a Black-Scholes option-pricing model in order to determine the fair value of the redeemable preferred stock warrant, with such value determined on an as-converted basis. Certain inputs used in the model are unobservable. The fair values could change significantly based on future market conditions.
	The fair values of these financial assets and the redeemable preferred stock warrant were determined using the following inputs (in thousands):
		Fair value measurements at
		December 31, 2012 using
		Level 1		Level 2		Level 3		Total
	Cash equivalents:
	Money market funds	$	15,554	$	—	$	—	$	15,554
	Other liabilities:
	Redeemable preferred stock warrants	—		—		601		601
		Fair value measurements at
		September 30, 2013 using
		Level 1		Level 2		Level 3		Total
	Cash equivalents:
	Money market funds	$	79,004	$	—	$	—	$	79,004
	Other liabilities:
	Redeemable preferred stock warrants	—		—		—		—
	Upon the closing of the Company’s initial public offering, the warrants to purchase shares of the Company’s redeemable convertible preferred stock were net exercised.  The then-current aggregate fair value of the warrant liability of $1.3 million was reclassified from long-term liabilities to additional paid-in capital, a component of stockholders’ equity, and the Company ceased to record any further periodic fair value adjustments relating to the warrant liability.

Acquisition

Acquisition	9 Months Ended
	Sep. 30, 2013
Acquisition	'
Acquisition	'
	4. Acquisition
	On June 21, 2013, the Company acquired 100% of the stock of a technology company. The fair value of the aggregate purchase price was approximately $259,000, which consisted of (1) a cash payment of $10,000, (2) notes payable of approximately $74,000, and (3) options to purchase shares of common stock with an exercise price of $11.28.  The estimated fair value of separately identifiable intangible assets will be amortized over an estimated useful life of two to three years. As a result, future amortization expense related to the acquisition will be $48,000, $96,000, $88,000, and $40,000 for the years ending December 31, 2013, 2014, 2015, and 2016, respectively.

LongTerm_Obligations

Long-Term Obligations	9 Months Ended
	Sep. 30, 2013
Long-Term Obligations	'
Long-Term Obligations	'
	5. Long-Term Obligations
	Loan and Security Agreement
	In June 2013, the Company entered into an Amended and Restated Loan and Security Agreement with Silicon Valley Bank (the “SVB Agreement”), which consists of a revolving credit facility of $13.0 million (subject to certain borrowing base restrictions) and term borrowings to fund purchases of property and equipment. All borrowings under the SVB Agreement are collateralized by the general assets of the Company. The credit facility has a variable rate of interest of prime (as published in the Wall Street Journal) or LIBOR plus 2.50%, as selected by the Company. The rate was 3.25% at September 30, 2013. In addition, the Company pays an annual commitment fee of $20,000 and a quarterly unused line fee of 0.375% based on the difference between the borrowing commitment of $13.0 million and the then-current balance. The SVB Agreement provides for $2.75 million in term borrowings to fund purchase of property and equipment through May 2014, of which $2.0 million was available at September 30, 2013. Term borrowings are payable in 39 equal monthly payments of principal plus interest and bear interest at prime plus 0.50%, which was 3.75% at September 30, 2013.
	Borrowing under the revolving credit facility is subject to certain collateral restrictions relating primarily to our accounts receivable and inventory levels. As of September 30, 2013, our total borrowing capacity was approximately $13.0 million, and no borrowings were outstanding. The revolving credit facility has a maturity date of May 29, 2015.
	The SVB Agreement contains various restrictive and financial covenants and the Company was in compliance with each of these covenants as of September 30, 2013.
	Settlement Obligation
	The Company has entered into various settlement agreements relating to alleged patent infringements, which included future payments under non-interest bearing, unsecured notes payable. The carrying values of the notes payable have been discounted using an implied interest rate of 3.75% and is included in accrued and other long-term liabilities in the accompanying condensed consolidated balance sheets.
	Upon closing of the Company’s initial public offering, the balance due on one of the settlement obligations was accelerated and became immediately due and payable.  As a result, the Company made a final payment on this obligation of $2.1 million on August 12, 2013.  The difference between the carrying value of the note and the payment was recorded as a $0.2 million charge to interest expense.
	Future annual payments on the settlement obligations as of September 30, 2013 are shown in the table below (in thousands):
	2013	$	20
	2014	920
	2015	20
	2016	20
		980
	Less amount representing interest	(33		)
	Present value of settlement obligations	947
	Less current portion of settlement obligations	(887		)
	Long-term portion of settlement obligations	$	60

Income_Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2013
Income Taxes	'
Income Taxes	'
	6. Income Taxes
	In order to determine the quarterly provision for income taxes, the Company considers the estimated annual effective tax rate, which is based on expected annual income and statutory tax rates in the various jurisdictions in which the Company operates. Certain significant or unusual items are separately recognized in the quarter during which they occur and can be a source of variability in the effective tax rates from quarter to quarter.
	Income tax expense was $0 and $0.1 million for the three months ended September 30, 2012 and 2013, respectively, or approximately 0% and 6% of income before income taxes, respectively.  Income tax expense was $0 and $0.1 million for the nine months ended September 30, 2012 and 2013, respectively, or approximately 0% and 10% of income before income taxes, respectively. The effective tax rate for the three and nine months ended September 30, 2013 differs from the U.S. federal statutory rate of 34% primarily due to state income taxes, foreign income taxes, U.S. federal alternative minimum tax, incentive stock options, and the domestic valuation allowance offsetting most of the statutory rate.
	At September 30, 2012 and 2013, the Company had a full valuation allowance against the deferred tax assets of its domestic operations as it believes it is more likely than not that these benefits will not be realized. At September 30, 2012, the Company also had a full valuation allowance against the deferred tax assets of its operations in the UK; however, the foreign valuation allowance has subsequently been released.  Significant judgment is required in making this assessment, and it is very difficult to predict when, if ever, the assessment may conclude that the remaining portion of the deferred tax assets are realizable.
	The Company files income tax returns in the United States, including various state and local jurisdictions. The Company’s subsidiaries file income tax returns in the United Kingdom, Hong Kong, China and India. The Company is subject to examination in the United States, the United Kingdom, Hong Kong, China, and India as well as various state jurisdictions. As of September 30, 2013, the Company was not under examination by any tax authorities.

Redeemable_Convertible_Preferr

Redeemable Convertible Preferred Stock and Stockholders' Deficit	9 Months Ended
	Sep. 30, 2013
Redeemable Convertible Preferred Stock and Stockholders' Deficit	'
Redeemable Convertible Preferred Stock and Stockholders' Deficit	'
	7. Redeemable Convertible Preferred Stock and Stockholders’ Deficit
	Redeemable Convertible Preferred Stock
	Upon closing of the Company’s initial public offering, the 15,293,960 shares of issued and outstanding redeemable convertible preferred stock were converted into common stock. Each share of redeemable convertible preferred stock, shown as issued and outstanding in the table below, was converted into one share of common stock.  The carrying value of the redeemable preferred stock at August 7, 2013 of $116.3 million was reclassified to common stock and additional paid-in capital.
	Redeemable convertible preferred stock consisted of the following at December 31, 2012 and August 7, 2013 (in thousands, except share data):
		Shares		Shares		Aggregate
		Authorized		Issued and		Liquidation
				Outstanding		Preference
	Series A	8,150,000		1,567,306		$	4,075
	Series B	18,124,230		3,485,425		14,735
	Series C	14,215,791		2,726,476		15,000
	Series D	7,789,215		1,497,921		15,890
	Series E	5,045,662		965,927		11,000
	Series F	5,988,024		1,151,542		20,000
	Series G	8,677,338		1,668,707		15,450
	Series G-1	2,073,148		216,015		2,000
	Series H	13,100,000		2,014,641		20,000
		83,163,408		15,293,960		$	118,150
	Prior to their conversion, the Series A, Series B, Series C, Series D, Series E, Series F, Series G, Series G-1 and Series H redeemable convertible preferred stockholders were entitled to receive, when, as and if declared by the Company’s Board of Directors, dividends at a rate of $0.21, $0.34, $0.44, $0.85, $0.91, $1.39, $0.74, $0.74, and $0.79 per share per year, respectively. To the extent that additional dividends were declared by the Board of Directors, those amounts would have been distributed equally among the Preferred Stockholders and common stockholders. As of September 30, 2013, no dividends had been declared by the Board of Directors.
	Warrants to Purchase Stock and Preferred Stock Warrant Liability
	Warrants to purchase common and preferred stock are summarized in the following table:
		Number of Shares Subject to Warrant
		December 31,		September 30,		Exercise Price
		2012		2013
	Warrants to purchase shares of common stock	71,153		—		$	7.49
	Warrants to purchase shares of common stock	470,082		—		9.93
	Warrants to purchase Series C redeemable convertible preferred stock (1)	7,325		—		5.5
	Warrants to purchase Series E redeemable convertible preferred stock (1)	4,390		—		11.39
	Warrants to purchase shares of common stock (1)	—		7,325		5.5
	Warrants to purchase shares of common stock (1)	—		4,390		11.39
	Warrants to purchase Series G-1 redeemable convertible preferred stock	182,666		—		9.26
		735,616		11,715
	(1)                                 Warrants to purchase Series C and Series E redeemable convertible preferred stock were converted into warrants to purchase shares of common stock upon the closing of the Company’s initial public offering.
	Upon the closing of the Company’s initial public offering, warrants to purchase 723,901 shares of the Company’s common and preferred stock were net exercised, and the Company issued 293,232 shares of common stock to the holders of the warrants.
	In 2009, the Series G-1 investors received warrants to purchase 182,666 shares of Series G-1 redeemable convertible preferred stock at a price of $9.26 per share. The warrants became immediately exercisable upon the closing of the Series G-1 financing and the fair value of $0.4 million was recorded as a liability with the offsetting charge to expense. Because the holders of the preferred stock were able to elect to redeem the shares for cash, the Company’s outstanding preferred stock warrants were classified as liabilities and were revalued at the end of each reporting period using the Black-Scholes option-pricing valuation model. Changes in fair value were reflected in the Company’s statements of operations as other income or expense. The fair market value of the Company’s common stock was used to value the warrant liability using the Black-Scholes option-pricing model. Upon the effective date of the Company’s initial public offering, the Company adjusted the liability based upon the offering price of $16.00 per share. As a result, the Company recognized $29,000 of other income and $0.7 million of other expense during the three- and nine-month periods ended September 30, 2013.
	As discussed above, upon the closing of the Company’s initial public offering, the warrants to purchase shares of the Company’s redeemable convertible preferred stock were net exercised.  Of the 293,232 shares issued, the Company issued 76,964 shares of common stock to the warrant holder of Series G-1 redeemable convertible preferred stock. The then-current aggregate fair value of the warrant liability of $1.3 million was reclassified from long-term liabilities to additional paid-in capital, a component of stockholders’ equity, and the Company ceased to record any further periodic fair value adjustments relating to the warrant liability.
	Stock Options
	In 2003, the Board of Directors adopted the 2003 Equity Incentive Plan (the “2003 Plan”), which provides for the granting of nonqualified and incentive stock options, stock appreciation rights, stock awards and restricted stock. Under the 2003 Plan, the Company may grant nonqualified and incentive stock options to directors, employees and non-employees providing services to the Company. The Board of Directors, on an option-by-option basis, determines the number of shares, terms and exercise period. Options granted generally have a ten-year life and vest over a period of four years. The exercise price of options on the date of grant is equivalent to the estimated fair value of the stock as determined by the Board of Directors based upon information available to it at the time of grant. Because there was no public market for the common stock, prior to the Company’s initial public offering, the Company’s Board of Directors determined the fair value of the Company’s common stock based on a variety of factors, including periodic valuations of the Company’s common stock, arm’s-length sales of the Company’s common stock, the Company’s financial position, historical financial performance, projected financial performance, valuations of publicly traded peer companies and the illiquid nature of the Company’s common stock.
	On June 11, 2013, the Company’s Board of Directors adopted the 2013 Stock Option and Incentive Plan (the “2013 Plan”), which was subsequently approved by the Company’s stockholders.  The 2013 Plan became effective as of the closing of the Company’s initial public offering. The Company initially reserved 2,390,401 shares of its Common Stock for issuance of awards under the 2013 Plan. To the extent that any awards outstanding under the 2003 Plan are forfeited or lapse unexercised subsequent to August 1, 2013, the shares of common stock subject to such awards will become available for issuance under the 2013 Plan.  As of September 30, 2013, an aggregate of 2,328,805 shares were available for issuance under the 2013 Plan. The 2013 Plan provides for annual increases in the number of reserved shares of up to 5% of the outstanding number of shares of the Company’s Common Stock.
	A summary of stock option activity for the nine months ended September 30, 2013 is presented below:
		Shares		Weighted			Weighted			Weighted
		Subject to		Average			Average			Average
		Options		Grant Date			Exercise			Remaining
		Outstanding		Fair Value			Price			Contractual
										Life (Years)
	Balance at December 31, 2012	4,649,238		$	3.33		$	5.56		7.2
	Granted	456,098		10.28			13.63
	Exercised	(88,582	)	2.39			4.14
	Expired	(31,722	)	3.39			5.62
	Forfeited	(35,467	)	4.6			7.33
	Balance at September 30, 2013	4,949,565		3.99			6.36			6.7
	Exercisable options at September 30, 2013	3,061,051		$	2.79		$	4.65		5.5
	Vested and expected to vest at September 30, 2013	4,607,844		3.85			6.19
	The following table summarizes information about stock options outstanding and exercisable at September 30, 2013:
		Options Outstanding							Options Exercisable
	Range of Exercise Prices	Weighted			Number of		Weighted-		Number of		Weighted-
		Average			Underlying		Average		Underlying		Average
		Exercise			Shares		Remaining		Shares		Remaining
		Price					Contractual				Contractual
							Life (in				Life (in
							years)				years)
	$0.26 - 1.30	$	0.56		190,939		1.2		190,939		1.2
	1.35 - 2.60	2.18			473,347		2.7		473,347		2.7
	2.65 - 3.90	3.23			325,523		3.8		325,523		3.8
3.95 - 5.20	4.87			954,522		5.5		926,448		5.5
5.25 - 6.50	6.19			1,734,885		8		933,316		7.9
6.55 - 7.80	7.49			118,947		6.8		95,260		6.8
7.85 - 9.10	8.84			239,893		8.7		81,075		8.7
9.15 – 22.77	11.4			911,509		8.9		35,143		9.1
				4,949,565				3,061,051
The following table summarizes the aggregate intrinsic-value of options exercised, outstanding and exercisable (in thousands):
	For the nine months ended
	and as of September 30, 2013
Options Exercised	$	1,130
Options Outstanding	55,147
Options Exercisable	38,783
The fair value of each option award is estimated on the date of grant using the Black-Scholes option-pricing model with the following assumptions:
	Three Months Ended September 30,				Nine Months Ended September 30,
	2012		2013		2012		2013
Expected volatility	61	%	57	%	61-63	%	56-59	%
Expected dividends	0	%	0	%	0	%	0	%
Expected terms (in years)	6.0-6.1		5.5-6.1		5.5-6.1		3.3-7.2
Risk-free rate	0.8	%	1.5-1.7	%	0.8-0.9	%	0.8-1.7	%
Forfeiture rate	7.9	%	7.2	%	7.9	%	7.2	%
Total stock-based compensation expense has been classified as follows in the accompanying statements of operations (in thousands):
	Three Months						Nine Months
	Ended						Ended
	September 30,						September 30,
	2012			2013			2012			2013
Cost of revenue	$	18		$	15		$	53		$	46
Research and development	202			419			461			974
Sales and marketing	139			187			421			543
General and administrative	363			319			1,159			1,085
Total stock-based compensation expense	$	722		$	940		$	2,094		$	2,648
At September 30, 2013, there was $8.1 million of total unrecognized compensation cost related to non-vested stock option awards that will be recognized over a weighted-average period of 3.1 years.

Related_Party_Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2013
Related Party Transactions	'
Related Party Transactions	'
	8. Related Party Transactions
	The Company has entered into sales agreements with certain of its investors. The following table sets forth revenue from product sales to companies affiliated with these investors (in thousands):
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
		2012		2013		2012		2013
	Company 1	$	747	$	694	$	1,567	$	2,059
	Company 2	211		—		813		128
	Company 3	372		262		1,139		748
	Company 4	368		4		784		423
		$	1,698	$	960	$	4,303	$	3,358
	As of December 31, 2012 and September 30, 2013, the Company had accounts receivable from these companies totaling $1.5 million and $0.8 million, respectively.  Purchase and payment terms with these customers are consistent with other non-affiliated companies.

Commitments_and_Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2013
Commitments and Contingencies	'
Commitments and Contingencies	'
	9. Commitments and Contingencies
	Operating Leases
	The Company leases office and warehouse space under operating leases that expire between 2013 and 2018. The terms of the leases include periods of free rent, options for the Company to extend the leases (three to five years) and increasing rental rates over time. The Company recognizes rental expense under these operating leases on a straight-line basis over the lives of the leases and has accrued for rental expense recorded but not paid.
	Rental expense was approximately $0.3 million for the three months ended September 30, 2012 and 2013, and $0.7 million and $1.0 million for the nine months ended September 30, 2012 and 2013, respectively.
	Future minimum rental payments required under non-cancelable operating leases with initial or remaining terms in excess of one year consist of the following as of September 30, 2013 (in thousands):
	2013	$	370
	2014	1,452
	2015	1,451
	2016	1,312
	2017	1,124
	Thereafter	557
		$	6,266
	Purchase Commitments
	The Company had non-cancellable purchase commitments for the purchase of inventory, which extend through May 2014 totaling approximately $23.9 million at September 30, 2013.
	Indemnification
	The Company has agreed to indemnify its officers and directors for certain events or occurrences, while the officer or director is or was serving at the Company’s request in such capacity. The maximum amount of potential future indemnification is unlimited; however, the Company has a director and officer insurance policy that provides corporate reimbursement coverage that limits its exposure and enables it to recover a portion of any future amounts paid. The Company is unable to reasonably estimate the maximum amount that could be payable under these arrangements since these obligations are not capped but are conditional to the unique facts and circumstances involved. Accordingly, the Company has no liabilities recorded for these agreements as of September 30, 2013.
	Employment Agreements
	The Company has signed employment agreements with certain executive officers who are entitled to receive certain benefits if their employment is terminated by the Company, including severance payments, accelerated vesting of stock options and continuation of certain insurance benefits.
	Legal Matters
	The Company is subject to various lawsuits and other claims that arise from time to time in the ordinary course of business. These actions may be based on alleged patent infringement or other matters. The Company intends to defend itself vigorously against any such actions. The Company establishes reserves for specific liabilities in connection with legal actions that it deems to be probable and estimable.
	In management’s opinion, the Company is not currently involved in any legal proceedings that, individually or in the aggregate, could have a material effect on the Company’s financial condition, operations, or cash flows.

Description_of_Business_and_Su1

Description of Business and Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2013
Description of Business and Summary of Significant Accounting Policies	'
Reclassifications	'
	Reclassifications
	Certain prior-year amounts have been reclassified in order to conform to the current-year presentation. The reclassification is related to gains or losses on inventory purchase commitments from accrued liabilities into the applicable caption on the statements of cash flows. This reclassification had no effect on the previously reported net cash (used in) provided by operating activities.
Unaudited Interim Financial Statements	'
	Unaudited Interim Financial Statements
	The accompanying condensed consolidated balance sheets and the condensed consolidated statements of operations, comprehensive income (loss), and cash flows are unaudited. These unaudited interim condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (‘‘GAAP’’) on the same basis as the audited consolidated financial statements and, in the opinion of management, reflect all adjustments, consisting of only normal recurring adjustments, considered necessary to present fairly the Company’s financial position, results of operations and cash flows. The results of operations for the three and nine months ended September 30, 2013 are not necessarily indicative of the results that may be expected for the year ending December 31, 2013, or any other future interim or annual period.
	These unaudited interim condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and related notes included in the Company’s Prospectus filed with the Securities and Exchange Commission (the “SEC”) on August 2, 2013. The December 31, 2012 consolidated balance sheet included herein was derived from the audited financial statements as of that date.
Basis of Presentation	'
	Basis of Presentation
	The unaudited condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated in the unaudited condensed consolidated financial statements.
Initial Public Offering	'
	Initial Public Offering
	On August 7, 2013, the Company completed its initial public offering (“IPO”) of common stock in which the Company sold and issued 4,600,000 shares of common stock at a price of $16.00 per share. As a result of the IPO, the Company raised a total of $73.6 million in gross proceeds, or approximately $65.6 million in net proceeds after deducting underwriting discounts and commissions of $5.2 million and offering expenses of approximately $2.8 million.
Stock Split	'
	Stock Split
	In July 2013, the Company’s board of directors and stockholders approved an amendment to the Company’s amended and restated certificate of incorporation. The amendment provided for a 1-for-5.2 reverse stock split of the outstanding common stock and outstanding convertible preferred stock (collectively, “Capital Stock”), which became effective on July 18, 2013. Accordingly, (i) every 5.2 shares of Capital Stock have been combined into one share of Capital Stock, (ii) the number of shares of Capital Stock into which each outstanding option or warrant to purchase Capital Stock is exercisable, as the case may be, have been proportionately decreased on a 5.2-for-1 basis, and (iii) the exercise price for each such outstanding option or warrant to purchase Capital Stock has been proportionately increased on a 1-for-5.2 basis. All of the share numbers, share prices, and exercise prices have been adjusted within these financial statements, on a retroactive basis, to reflect this 1-for-5.2 reverse stock split.
Segment Reporting	'
	Segment Reporting
	Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker, the Chief Executive Officer, in making decisions regarding resource allocation and accessing performance. To date, the Company has viewed its operations and manages its business as one segment.
Concentrations of Risk	'
	Concentrations of Risk
	Financial instruments that potentially subject the Company to a concentration of credit risk consist of cash and cash equivalents and accounts receivable. The Company deposits cash and cash equivalents with one high-credit-quality financial institution and maintains balances that exceed federally insured amounts. The Company has policies that limit its investments as to types of investments, maturity, liquidity, credit quality, concentration and diversification of issuers.
	The Company’s accounts receivable are derived from revenue earned from customers primarily located in the United States and Canada. The Company’s sales to customers located outside the United States are generally denominated in United States dollars, except for sales to customers located in the United Kingdom, which are denominated in pounds sterling. There were no individual account balances greater than 10% of total accounts receivable at December 31, 2012 and September 30, 2013.
	No customer accounted for more than 10% of total revenue for the three- and nine-month periods ended September 30, 2012 and 2013.
	The Company relies on a limited number of suppliers for its contract manufacturing. A significant disruption in the operations of these manufacturers would impact the production of the Company’s products for a substantial period of time, which could have a material adverse effect on the Company’s business, financial condition and results of operations.
Geographic Information	'
	Geographic Information
	The Company’s revenue includes amounts earned through sales to customers located outside of the United States. With the exception of Canada, no single foreign country accounted for more than 10% of total revenue for the three- and nine-month periods ended September 30, 2012 and 2013. The following table sets forth revenue from the U.S., Canadian and all other international customers combined (in thousands):
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
		2012			2013			2012			2013
	Revenue-United States	$	17,845		$	22,264		$	51,347		$	61,430
	Revenue-Canada	3,344			3,641			9,184			10,690
	Revenue-all other international sources	7,416			7,736			18,316			20,635
	Total revenue	$	28,605		$	33,641		$	78,847		$	92,755
	International revenue (excluding Canada) as a percent of total revenue	26		%	23		%	23		%	22		%
Use of Accounting Estimates	'
	Use of Accounting Estimates
	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, the Company evaluates its estimates including those related to revenue recognition, sales returns, provisions for doubtful accounts, product warranty, inventory obsolescence, litigation, determination of fair value of stock options, deferred tax asset valuation allowances and income taxes. Actual results may differ from those estimates.
Product Warranty	'
	Product Warranty
	The Company provides its customers a limited product warranty of two years, which requires the Company to repair or replace defective products during the warranty period at no cost to the customer. The Company estimates the costs that may be incurred to replace or repair defective products and records a reserve at the time revenue is recognized. Factors that affect the Company’s warranty liability include the number of installed systems, the Company’s historical experience and management’s judgment regarding anticipated rates of product warranty returns. The Company assesses the adequacy of its recorded warranty liability each period and makes adjustments to the liability as necessary.
	The following table presents the changes in the product warranty liability (in thousands):
		Warranty Liability
	Balance at December 31, 2012	$	1,155
	Warranty costs accrued	420
	Warranty claims	(414		)
	Balance at September 30, 2013	$	1,161
Fair Value of Financial Instruments	'
	Fair Value of Financial Instruments
	The carrying amounts reported in the accompanying condensed consolidated financial statements for cash and cash equivalents, accounts payable and accrued liabilities approximate their fair value because of the short-term nature of the accounts. The fair value of the notes payable approximates its carrying value based on the variable nature of interest rates and current market rates available to the Company.
Net Income (Loss) Per Share	'
	Net Income (Loss) Per Share
	Basic net income (loss) per share is computed using the weighted-average number of common shares outstanding during the period. Diluted net income (loss) per share is computed using the weighted-average number of common shares outstanding and potentially dilutive common shares outstanding during the period that have a dilutive effect on net income per share. Potentially dilutive common shares result from the assumed exercise of outstanding stock options and the assumed conversion of outstanding convertible preferred stock and warrants using the if-converted method. In a net loss position, diluted net loss per share is computed using only the weighted-average number of common shares outstanding during the period, as any additional common shares would be anti-dilutive.
	The following table presents the reconciliation of the numerator and denominator used in the calculation of basic and diluted net income (loss) per share (in thousands):
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
		2012			2013			2012			2013
	Numerator:
	Net income (loss)	$	(4,092	)	$	1,731		$	(6,256	)	$	1,233
	Denominator:
	Weighted average common stock outstanding for basic net income (loss) per common share	2,363			14,389			2,324			6,511
	Effect of dilutive securities—stock options, convertible preferred stock, and warrants to purchase common stock and preferred stock	—			9,167			—			14,695
	Weighted average common shares and dilutive securities outstanding	2,363			23,556			2,324			21,206
	The following weighted-average common stock equivalents were anti-dilutive and therefore were excluded from the calculation of diluted net income (loss) per share (in thousands):
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
		2012		2013		2012		2013
	Convertible preferred stock	15,294		—		15,294		—
	Options to purchase common stock	4,366		253		4,312		355
	Warrants to purchase common stock	541		—		541		—
	Warrants to purchase preferred stock	194		—		194		1
	Total	20,395		253		20,341		356
Recent Accounting Pronouncements	'
	Recent Accounting Pronouncements
	In February 2013, the FASB issued ASU 2013-02, ‘‘Comprehensive Income: Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income.’’ The amended guidance requires an entity to present the effects on the line items of net income of significant reclassifications out of accumulated other comprehensive income if the amount being reclassified is required under U.S. generally accepted accounting principles to be reclassified in its entirety to net income in the same reporting period. The guidance is effective prospectively for the reporting periods beginning after December 15, 2012. This new guidance was effective for the Company beginning January 1, 2013. The adoption of this guidance did not have an impact on the Company’s results of operations, financial position, or cash flows as it relates only to financial statement presentation.

Description_of_Business_and_Su2

Description of Business and Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2013
Description of Business and Summary of Significant Accounting Policies	'
Schedule of revenue from U.S., Canadian and all other international customers combined	'
	The following table sets forth revenue from the U.S., Canadian and all other international customers combined (in thousands):
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
		2012			2013			2012			2013
	Revenue-United States	$	17,845		$	22,264		$	51,347		$	61,430
	Revenue-Canada	3,344			3,641			9,184			10,690
	Revenue-all other international sources	7,416			7,736			18,316			20,635
	Total revenue	$	28,605		$	33,641		$	78,847		$	92,755
	International revenue (excluding Canada) as a percent of total revenue	26		%	23		%	23		%	22		%
Schedule of changes in the product warranty liability	'
	The following table presents the changes in the product warranty liability (in thousands):
		Warranty Liability
	Balance at December 31, 2012	$	1,155
	Warranty costs accrued	420
	Warranty claims	(414		)
	Balance at September 30, 2013	$	1,161
Schedule of reconciliation of the numerator and denominator used in the calculation of basic and diluted net income (loss) per share	'
	The following table presents the reconciliation of the numerator and denominator used in the calculation of basic and diluted net income (loss) per share (in thousands):
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
		2012			2013			2012			2013
	Numerator:
	Net income (loss)	$	(4,092	)	$	1,731		$	(6,256	)	$	1,233
	Denominator:
	Weighted average common stock outstanding for basic net income (loss) per common share	2,363			14,389			2,324			6,511
	Effect of dilutive securities—stock options, convertible preferred stock, and warrants to purchase common stock and preferred stock	—			9,167			—			14,695
	Weighted average common shares and dilutive securities outstanding	2,363			23,556			2,324			21,206
Schedule of anti-dilutive weighted-average common stock equivalents excluded from the calculation of diluted net income (loss) per share	'
	The following weighted-average common stock equivalents were anti-dilutive and therefore were excluded from the calculation of diluted net income (loss) per share (in thousands):
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
		2012		2013		2012		2013
	Convertible preferred stock	15,294		—		15,294		—
	Options to purchase common stock	4,366		253		4,312		355
	Warrants to purchase common stock	541		—		541		—
	Warrants to purchase preferred stock	194		—		194		1
	Total	20,395		253		20,341		356

Balance_Sheet_Components_Table

Balance Sheet Components (Tables)	9 Months Ended
	Sep. 30, 2013
Balance Sheet Components	'
Schedule of inventories	'
	Inventories consisted of the following (in thousands):
		December 31,			September 30,
		2012			2013
	Finished goods	$	12,306		$	14,202
	Component parts	209			1,357
		$	12,515		$	15,559
Schedule of property and equipment, net	'
	Property and equipment, net consisted of the following (in thousands):
		December 31,			September 30,
		2012			2013
	Computer equipment and software	$	3,518		$	3,817
	Manufacturing tooling and test equipment	2,731			2,647
	Furniture and fixtures	1,801			1,965
	Lab and warehouse equipment	1,974			2,311
	Marketing equipment	419			424
	Leasehold improvements	803			1,390
		11,246			12,554
	Less: accumulated depreciation	(8,580		)	(8,914		)
		$	2,666		$	3,640
Schedule of intangible assets, net	'
	Intangible assets, net consisted of the following (in thousands):
		December 31,			September 30,
		2012			2013
	Acquired technology	$	1,357		$	1,628
	Less: accumulated amortization	(431		)	(658		)
		$	926		$	970
Schedule of other assets	'
	Other assets consisted of the following (in thousands):
		December 31,			September 30,
		2012			2013
	Prepaid licensing	700			735
	Deposits	187			395
		$	887		$	1,130
Schedule of accrued liabilities	'
	Accrued liabilities consisted of the following (in thousands):
		December 31,			September 30,
		2012			2013
	Current portion of settlement obligations (see Note 5)	$	2,229		$	887
	Sales returns and warranty accruals	2,045			2,104
	Compensation accruals	1,495			2,118
	Other accrued liabilities	802			439
		$	6,571		$	5,548

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2013
Fair Value Measurements	'
Schedule of fair value of financial instruments measured on a recurring basis	'
	The fair values of these financial assets and the redeemable preferred stock warrant were determined using the following inputs (in thousands):
		Fair value measurements at
		December 31, 2012 using
		Level 1		Level 2		Level 3		Total
	Cash equivalents:
	Money market funds	$	15,554	$	—	$	—	$	15,554
	Other liabilities:
	Redeemable preferred stock warrants	—		—		601		601
		Fair value measurements at
		September 30, 2013 using
		Level 1		Level 2		Level 3		Total
	Cash equivalents:
	Money market funds	$	79,004	$	—	$	—	$	79,004
	Other liabilities:
	Redeemable preferred stock warrants	—		—		—		—

LongTerm_Obligations_Tables

Long-Term Obligations (Tables)	9 Months Ended
	Sep. 30, 2013
Long-Term Obligations	'
Schedule of future annual payments on the settlement obligations	'
	Future annual payments on the settlement obligations as of September 30, 2013 are shown in the table below (in thousands):
	2013	$	20
	2014	920
	2015	20
	2016	20
		980
	Less amount representing interest	(33		)
	Present value of settlement obligations	947
	Less current portion of settlement obligations	(887		)
	Long-term portion of settlement obligations	$	60

Redeemable_Convertible_Preferr1

Redeemable Convertible Preferred Stock and Stockholders' Deficit (Tables)	9 Months Ended
	Sep. 30, 2013
Redeemable Convertible Preferred Stock and Stockholders' Deficit	'
Schedule of redeemable convertible preferred stock	'
	Redeemable convertible preferred stock consisted of the following at December 31, 2012 and August 7, 2013 (in thousands, except share data):
		Shares		Shares		Aggregate
		Authorized		Issued and		Liquidation
				Outstanding		Preference
	Series A	8,150,000		1,567,306		$	4,075
	Series B	18,124,230		3,485,425		14,735
	Series C	14,215,791		2,726,476		15,000
	Series D	7,789,215		1,497,921		15,890
	Series E	5,045,662		965,927		11,000
	Series F	5,988,024		1,151,542		20,000
	Series G	8,677,338		1,668,707		15,450
	Series G-1	2,073,148		216,015		2,000
	Series H	13,100,000		2,014,641		20,000
		83,163,408		15,293,960		$	118,150
Summary of warrants to purchase common and preferred stock	'
	Warrants to purchase common and preferred stock are summarized in the following table:
		Number of Shares Subject to Warrant
		December 31,		September 30,		Exercise Price
		2012		2013
	Warrants to purchase shares of common stock	71,153		—		$	7.49
	Warrants to purchase shares of common stock	470,082		—		9.93
	Warrants to purchase Series C redeemable convertible preferred stock (1)	7,325		—		5.5
	Warrants to purchase Series E redeemable convertible preferred stock (1)	4,390		—		11.39
	Warrants to purchase shares of common stock (1)	—		7,325		5.5
	Warrants to purchase shares of common stock (1)	—		4,390		11.39
	Warrants to purchase Series G-1 redeemable convertible preferred stock	182,666		—		9.26
		735,616		11,715
	(1)                                 Warrants to purchase Series C and Series E redeemable convertible preferred stock were converted into warrants to purchase shares of common stock upon the closing of the Company’s initial public offering.
Summary of stock option activity	'
		Shares		Weighted			Weighted			Weighted
		Subject to		Average			Average			Average
		Options		Grant Date			Exercise			Remaining
		Outstanding		Fair Value			Price			Contractual
										Life (Years)
	Balance at December 31, 2012	4,649,238		$	3.33		$	5.56		7.2
	Granted	456,098		10.28			13.63
	Exercised	(88,582	)	2.39			4.14
	Expired	(31,722	)	3.39			5.62
	Forfeited	(35,467	)	4.6			7.33
	Balance at September 30, 2013	4,949,565		3.99			6.36			6.7
	Exercisable options at September 30, 2013	3,061,051		$	2.79		$	4.65		5.5
	Vested and expected to vest at September 30, 2013	4,607,844		3.85			6.19
Summary of information about stock options outstanding and exercisable	'
	The following table summarizes information about stock options outstanding and exercisable at September 30, 2013:
		Options Outstanding							Options Exercisable
	Range of Exercise Prices	Weighted			Number of		Weighted-		Number of		Weighted-
		Average			Underlying		Average		Underlying		Average
		Exercise			Shares		Remaining		Shares		Remaining
		Price					Contractual				Contractual
							Life (in				Life (in
							years)				years)
	$0.26 - 1.30	$	0.56		190,939		1.2		190,939		1.2
	1.35 - 2.60	2.18			473,347		2.7		473,347		2.7
	2.65 - 3.90	3.23			325,523		3.8		325,523		3.8
	3.95 - 5.20	4.87			954,522		5.5		926,448		5.5
	5.25 - 6.50	6.19			1,734,885		8		933,316		7.9
	6.55 - 7.80	7.49			118,947		6.8		95,260		6.8
	7.85 - 9.10	8.84			239,893		8.7		81,075		8.7
	9.15 – 22.77	11.4			911,509		8.9		35,143		9.1
					4,949,565				3,061,051
Summary of aggregate intrinsic-value of options exercised, outstanding and exercisable	'
	The following table summarizes the aggregate intrinsic-value of options exercised, outstanding and exercisable (in thousands):
		For the nine months ended
		and as of September 30, 2013
	Options Exercised	$	1,130
	Options Outstanding	55,147
	Options Exercisable	38,783
Schedule of assumptions used to estimate fair value of option awards	'
		Three Months Ended September 30,				Nine Months Ended September 30,
		2012		2013		2012		2013
	Expected volatility	61	%	57	%	61-63	%	56-59	%
	Expected dividends	0	%	0	%	0	%	0	%
	Expected terms (in years)	6.0-6.1		5.5-6.1		5.5-6.1		3.3-7.2
	Risk-free rate	0.8	%	1.5-1.7	%	0.8-0.9	%	0.8-1.7	%
	Forfeiture rate	7.9	%	7.2	%	7.9	%	7.2	%
Schedule of total stock-based compensation expense classified in statements of operations	'
	Total stock-based compensation expense has been classified as follows in the accompanying statements of operations (in thousands):
		Three Months						Nine Months
		Ended						Ended
		September 30,						September 30,
		2012			2013			2012			2013
	Cost of revenue	$	18		$	15		$	53		$	46
	Research and development	202			419			461			974
	Sales and marketing	139			187			421			543
	General and administrative	363			319			1,159			1,085
	Total stock-based compensation expense	$	722		$	940		$	2,094		$	2,648

Related_Party_Transactions_Tab

Related Party Transactions (Tables)	9 Months Ended
	Sep. 30, 2013
Related Party Transactions	'
Schedule of revenue from product sales to companies affiliated with investors	'
	The Company has entered into sales agreements with certain of its investors. The following table sets forth revenue from product sales to companies affiliated with these investors (in thousands):
		Three Months Ended				Nine Months Ended
		September 30,				September 30,
		2012		2013		2012		2013
	Company 1	$	747	$	694	$	1,567	$	2,059
	Company 2	211		—		813		128
	Company 3	372		262		1,139		748
	Company 4	368		4		784		423
		$	1,698	$	960	$	4,303	$	3,358

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2013
Commitments and Contingencies	'
Schedule of future minimum rental payments required under non-cancelable operating leases	'
	Future minimum rental payments required under non-cancelable operating leases with initial or remaining terms in excess of one year consist of the following as of September 30, 2013 (in thousands):
	2013	$	370
	2014	1,452
	2015	1,451
	2016	1,312
	2017	1,124
	Thereafter	557
		$	6,266

Description_of_Business_and_Su3

Description of Business and Summary of Significant Accounting Policies (Details) (USD $)	0 Months Ended		9 Months Ended
	Aug. 07, 2013	Jul. 18, 2013	Sep. 30, 2013
			item
IPO	'	'	'
Common stock sold and issued in IPO (in shares)	4,600,000	'	'
Common stock price (in dollars per share)	$16	'	'
Gross proceeds from the IPO	$73,600,000	'	'
Net proceeds from IPO	65,600,000	'	65,556,000
Underwriting discounts and commissions	5,200,000	'	'
Offering expenses	$2,800,000	'	'
Stock Split	'	'	'
Reverse stock split of outstanding common stock	'	0.1923	'
Segment Reporting	'	'	'
Number of operating segments	'	'	1
Concentrations of Risk	'	'	'
Number of high-credit-quality financial institutions with which cash and cash equivalents are deposited	'	'	1

Description_of_Business_and_Su4

Description of Business and Summary of Significant Accounting Policies (Details 2) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenue from U.S., Canadian and all other international customers combined	'	'	'	'
Total revenue	$33,641	$28,605	$92,755	$78,847
International revenue (excluding Canada) as a percent of total revenue	23.00%	26.00%	22.00%	23.00%
United States	'	'	'	'
Revenue from U.S., Canadian and all other international customers combined	'	'	'	'
Total revenue	22,264	17,845	61,430	51,347
Canada	'	'	'	'
Revenue from U.S., Canadian and all other international customers combined	'	'	'	'
Total revenue	3,641	3,344	10,690	9,184
All other international sources	'	'	'	'
Revenue from U.S., Canadian and all other international customers combined	'	'	'	'
Total revenue	$7,736	$7,416	$20,635	$18,316

Description_of_Business_and_Su5

Description of Business and Summary of Significant Accounting Policies (Details 3) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013
Product Warranty	'
Product warranty period	'2 years
Changes in the product warranty liability	'
Balance at beginning of period	$1,155
Warranty costs accrued	420
Warranty claims	-414
Balance at end of period	$1,161

Description_of_Business_and_Su6

Description of Business and Summary of Significant Accounting Policies (Details 4) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Numerator:	'	'	'	'
Net income (loss)	$1,731	($4,092)	$1,233	($6,256)
Denominator:	'	'	'	'
Weighted average common stock outstanding for basic net income (loss) per common share (in shares)	14,389	2,363	6,511	2,324
Effect of dilutive securities-stock options, convertible preferred stock, and warrants to purchase common stock and preferred stock (in shares)	9,167	'	14,695	'
Weighted average common shares and dilutive securities outstanding	23,556	2,363	21,206	2,324
Anti-dilutive weighted-average common stock equivalents excluded from the calculation of diluted net income (loss) per share	'	'	'	'
Total (in shares)	253	20,395	356	20,341
Convertible preferred stock	'	'	'	'
Anti-dilutive weighted-average common stock equivalents excluded from the calculation of diluted net income (loss) per share	'	'	'	'
Total (in shares)	'	15,294	'	15,294
Options to purchase common stock	'	'	'	'
Anti-dilutive weighted-average common stock equivalents excluded from the calculation of diluted net income (loss) per share	'	'	'	'
Total (in shares)	253	4,366	355	4,312
Warrants to purchase common stock	'	'	'	'
Anti-dilutive weighted-average common stock equivalents excluded from the calculation of diluted net income (loss) per share	'	'	'	'
Total (in shares)	'	541	'	541
Warrants to purchase preferred stock	'	'	'	'
Anti-dilutive weighted-average common stock equivalents excluded from the calculation of diluted net income (loss) per share	'	'	'	'
Total (in shares)	'	194	1	194

Balance_Sheet_Components_Detai

Balance Sheet Components (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Inventories	'	'
Finished goods	$14,202	$12,306
Component parts	1,357	209
Total inventories	15,559	12,515
Property and equipment, net	'	'
Property and equipment, gross	12,554	11,246
Less: accumulated depreciation	-8,914	-8,580
Property and equipment, net	3,640	2,666
Computer equipment and software	'	'
Property and equipment, net	'	'
Property and equipment, gross	3,817	3,518
Manufacturing tooling and test equipment	'	'
Property and equipment, net	'	'
Property and equipment, gross	2,647	2,731
Furniture and fixtures	'	'
Property and equipment, net	'	'
Property and equipment, gross	1,965	1,801
Lab and warehouse equipment	'	'
Property and equipment, net	'	'
Property and equipment, gross	2,311	1,974
Marketing equipment	'	'
Property and equipment, net	'	'
Property and equipment, gross	424	419
Leasehold improvements	'	'
Property and equipment, net	'	'
Property and equipment, gross	$1,390	$803

Balance_Sheet_Components_Detai1

Balance Sheet Components (Details 2) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Intangible assets, net	'	'
Intangible assets, net	$970	$926
Other assets	'	'
Prepaid licensing	735	700
Deposits	395	187
Other assets total	1,130	887
Accrued liabilities	'	'
Current portion of settlement obligations	887	2,229
Sales returns and warranty accruals	2,104	2,045
Compensation accruals	2,118	1,495
Other accrued liabilities	439	802
Total accrued liabilities	5,548	6,571
Acquired technology	'	'
Intangible assets, net	'	'
Intangible assets, gross	1,628	1,357
Less: accumulated amortization	-658	-431
Intangible assets, net	$970	$926

Fair_Value_Measurements_Detail

Fair Value Measurements (Details) (USD $)	Aug. 07, 2013	Sep. 30, 2013	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2012
	Preferred stock warrants	Measured on a recurring basis	Measured on a recurring basis	Measured on a recurring basis	Measured on a recurring basis	Measured on a recurring basis	Measured on a recurring basis
		Level 1	Level 1	Level 3	Total	Total	Total
		Money market funds	Money market funds	Redeemable preferred stock warrants	Redeemable preferred stock warrants	Money market funds	Money market funds
Fair Value Measurements	'	'	'	'	'	'	'
Cash equivalents	'	$79,004,000	$15,554,000	'	'	$79,004,000	$15,554,000
Other liabilities	'	'	'	601,000	601,000	'	'
Aggregate fair value of warrant liability	$1,300,000	'	'	'	'	'	'

Acquisition_Details

Acquisition (Details) (USD $)	9 Months Ended	0 Months Ended
	Sep. 30, 2013	Jun. 21, 2013	Jun. 21, 2013	Jun. 21, 2013
		Technology company	Technology company	Technology company
			Minimum	Maximum
Acquisition	'	'	'	'
Acquired stock (as a percent)	'	100.00%	'	'
Aggregate purchase price	'	$259,000	'	'
Cash payment	88,000	10,000	'	'
Notes payable	'	74,000	'	'
Exercise price of options to purchase shares of common stock (in dollars per share)	'	$11.28	'	'
Estimated useful life of identifiable intangible assets	'	'	'2 years	'3 years
Future amortization expense of acquired identifiable intangible assets	'	'	'	'
Remaining 2013	'	48,000	'	'
2014	'	96,000	'	'
2015	'	88,000	'	'
2016	'	$40,000	'	'

LongTerm_Obligations_Details

Long-Term Obligations (Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Jun. 30, 2013	Sep. 30, 2013	Jun. 30, 2013	Jun. 30, 2013	Sep. 30, 2013	Jun. 30, 2013	Jun. 30, 2013	Aug. 12, 2013	Sep. 30, 2013
			Revolving credit facility	Revolving credit facility	Revolving credit facility	Revolving credit facility	Term borrowings	Term borrowings	Term borrowings	Unsecured notes payable	Unsecured notes payable
					LIBOR	Prime rate	item		Prime rate		item
Long-Term Obligations	'	'	'	'	'	'	'	'	'	'	'
Maximum borrowing capacity	'	'	$13,000,000	'	'	'	'	$2,750,000	'	'	'
Variable interest rate basis	'	'	'	'	'LIBOR	'prime	'	'	'prime	'	'
Basis spread on variable rate (as a percent)	'	'	'	'	2.50%	'	'	'	0.50%	'	'
Interest rate at the end of period (as a percent)	'	'	'	3.25%	'	'	3.75%	'	'	'	'
Annual commitment fee	'	'	20,000	'	'	'	'	'	'	'	'
Commitment fee for quarterly unused capacity (as a percent)	'	'	0.38%	'	'	'	'	'	'	'	'
Number of equal monthly payments of principal plus interest	'	'	'	'	'	'	39	'	'	'	'
Current borrowing capacity	'	'	'	13,000,000	'	'	2,000,000	'	'	'	'
Borrowings outstanding	'	'	'	0	'	'	'	'	'	'	'
Settlement Obligation	'	'	'	'	'	'	'	'	'	'	'
Implied interest rate (as a percent)	'	'	'	'	'	'	'	'	'	'	3.75%
Number of settlement obligations accelerated and became due and payable	'	'	'	'	'	'	'	'	'	'	1
Final payment of obligation	'	'	'	'	'	'	'	'	'	2,100,000	'
Interest expense recorded	'	'	'	'	'	'	'	'	'	200,000	'
Future annual payments on the settlement obligations	'	'	'	'	'	'	'	'	'	'	'
2013	20,000	'	'	'	'	'	'	'	'	'	'
2014	920,000	'	'	'	'	'	'	'	'	'	'
2015	20,000	'	'	'	'	'	'	'	'	'	'
2016	20,000	'	'	'	'	'	'	'	'	'	'
Total	980,000	'	'	'	'	'	'	'	'	'	'
Less amount representing interest	-33,000	'	'	'	'	'	'	'	'	'	'
Present value of settlement obligations	947,000	'	'	'	'	'	'	'	'	'	'
Less current portion of settlement obligations	-887,000	-2,229,000	'	'	'	'	'	'	'	'	'
Long-term portion of settlement obligations	$60,000	'	'	'	'	'	'	'	'	'	'

Income_Taxes_Details

Income Taxes (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Income Taxes	'	'	'	'
Income tax expense	$103	$0	$132	$0
Effective income tax rate (as a percent)	6.00%	0.00%	10.00%	0.00%
U.S. federal statutory rate (as a percent)	34.00%	'	34.00%	'

Redeemable_Convertible_Preferr2

Redeemable Convertible Preferred Stock and Stockholders' Deficit (Details) (USD $)	9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Aug. 07, 2013	Dec. 31, 2012
Redeemable Convertible Preferred Stock	'	'	'
Converted into one share of common stock	1	'	'
Carrying value of redeemable preferred stock	'	$116,300	$116,313
Shares Authorized	0	83,163,408	83,163,408
Shares Issued	0	15,293,960	15,293,960
Shares Outstanding	0	15,293,960	15,293,960
Aggregate Liquidation Preference	0	118,150	118,150
Preferred stock dividend declared (in dollars per share)	$0	'	'
Series A	'	'	'
Redeemable Convertible Preferred Stock	'	'	'
Shares Authorized	'	8,150,000	8,150,000
Shares Issued	'	1,567,306	1,567,306
Shares Outstanding	'	1,567,306	1,567,306
Aggregate Liquidation Preference	'	4,075	4,075
Dividend rate per share per year (in dollars per share)	$0.21	'	'
Series B	'	'	'
Redeemable Convertible Preferred Stock	'	'	'
Shares Authorized	'	18,124,230	18,124,230
Shares Issued	'	3,485,425	3,485,425
Shares Outstanding	'	3,485,425	3,485,425
Aggregate Liquidation Preference	'	14,735	14,735
Dividend rate per share per year (in dollars per share)	$0.34	'	'
Series C	'	'	'
Redeemable Convertible Preferred Stock	'	'	'
Shares Authorized	'	14,215,791	14,215,791
Shares Issued	'	2,726,476	2,726,476
Shares Outstanding	'	2,726,476	2,726,476
Aggregate Liquidation Preference	'	15,000	15,000
Dividend rate per share per year (in dollars per share)	$0.44	'	'
Series D	'	'	'
Redeemable Convertible Preferred Stock	'	'	'
Shares Authorized	'	7,789,215	7,789,215
Shares Issued	'	1,497,921	1,497,921
Shares Outstanding	'	1,497,921	1,497,921
Aggregate Liquidation Preference	'	15,890	15,890
Dividend rate per share per year (in dollars per share)	$0.85	'	'
Series E	'	'	'
Redeemable Convertible Preferred Stock	'	'	'
Shares Authorized	'	5,045,662	5,045,662
Shares Issued	'	965,927	965,927
Shares Outstanding	'	965,927	965,927
Aggregate Liquidation Preference	'	11,000	11,000
Dividend rate per share per year (in dollars per share)	$0.91	'	'
Series F	'	'	'
Redeemable Convertible Preferred Stock	'	'	'
Shares Authorized	'	5,988,024	5,988,024
Shares Issued	'	1,151,542	1,151,542
Shares Outstanding	'	1,151,542	1,151,542
Aggregate Liquidation Preference	'	20,000	20,000
Dividend rate per share per year (in dollars per share)	$1.39	'	'
Series G	'	'	'
Redeemable Convertible Preferred Stock	'	'	'
Shares Authorized	'	8,677,338	8,677,338
Shares Issued	'	1,668,707	1,668,707
Shares Outstanding	'	1,668,707	1,668,707
Aggregate Liquidation Preference	'	15,450	15,450
Dividend rate per share per year (in dollars per share)	$0.74	'	'
Series G - 1	'	'	'
Redeemable Convertible Preferred Stock	'	'	'
Shares Authorized	'	2,073,148	2,073,148
Shares Issued	'	216,015	216,015
Shares Outstanding	'	216,015	216,015
Aggregate Liquidation Preference	'	2,000	2,000
Dividend rate per share per year (in dollars per share)	$0.74	'	'
Series H	'	'	'
Redeemable Convertible Preferred Stock	'	'	'
Shares Authorized	'	13,100,000	13,100,000
Shares Issued	'	2,014,641	2,014,641
Shares Outstanding	'	2,014,641	2,014,641
Aggregate Liquidation Preference	'	$20,000	$20,000
Dividend rate per share per year (in dollars per share)	$0.79	'	'

Redeemable_Convertible_Preferr3

Redeemable Convertible Preferred Stock and Stockholders' Deficit (Details 2) (USD $)

0 Months Ended

3 Months Ended

9 Months Ended

0 Months Ended

Aug. 07, 2013

Sep. 30, 2013

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2013

Dec. 31, 2012

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2013

Dec. 31, 2012

Dec. 31, 2012

Aug. 07, 2013

Dec. 31, 2012

Dec. 31, 2009

Redeemable preferred stock warrants

Redeemable preferred stock warrants

Common stock warrants

Common stock warrants

Common stock warrants

Common stock warrants

Preferred stock warrants

Preferred stock warrants

Preferred stock warrants

Preferred stock warrants

Preferred stock warrants

Other income (expense)

Other income (expense)

Transaction 1

Transaction 2

Transaction 3

Transaction 4

Series C redeemable convertible preferred stock

Series E redeemable convertible preferred stock

Series G-1 redeemable convertible preferred stock

Series G-1 redeemable convertible preferred stock

Series G-1 redeemable convertible preferred stock

Warrants to Purchase Stock and Preferred Stock Warrant Liability

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of Shares Subject to Warrant

'

11,715

735,616

'

'

71,153

470,082

7,325

4,390

7,325

4,390

'

182,666

182,666

Exercise Price (in dollars per share)

'

'

'

'

'

$7.49

$9.93

$5.50

$11.39

$5.50

$11.39

'

$9.26

$9.26

Number of warrants exercised to purchase shares of common and preferred stock (in shares)

723,901

'

'

'

'

'

'

'

'

'

'

'

'

'

Fair value of warrant

'

'

$601,000

'

'

'

'

'

'

'

'

$1,300,000

'

$400,000

Offering price (in dollars per share)

$16

'

'

'

'

'

'

'

'

'

'

'

'

'

Change in fair value included in other income (expense)

'

'

'

($29,000)

$700,000

'

'

'

'

'

'

'

'

'

Common stock, shares issued to warrant holders upon net exercise

293,232

'

'

'

'

'

'

'

'

'

'

76,964

'

'

Redeemable_Convertible_Preferr4

Redeemable Convertible Preferred Stock and Stockholders' Deficit (Details 3) (Stock options, USD $)	9 Months Ended	12 Months Ended	9 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Sep. 30, 2013	Aug. 07, 2013
			2003 Plan	2013 Plan	2013 Plan
Stock Options	'	'	'	'	'
Life of options granted	'	'	'10 years	'	'
Vesting period	'	'	'4 years	'	'
Number of shares available for issuance	'	'	'	2,328,805	2,390,401
Annual increase in shares authorized for issuance as a percentage of shares outstanding	'	'	'	'	5.00%
Shares Subject to Options Outstanding	'	'	'	'	'
Balance at the beginning of the period (in shares)	4,649,238	'	'	'	'
Granted (in shares)	456,098	'	'	'	'
Exercised (in shares)	-88,582	'	'	'	'
Expired (in shares)	-31,722	'	'	'	'
Forfeited (in shares)	-35,467	'	'	'	'
Balance at the end of the period (in shares)	4,949,565	4,649,238	'	'	'
Exercisable options (in shares)	3,061,051	'	'	'	'
Vested and expected to vest at the end of the period (in shares)	4,607,844	'	'	'	'
Weighted Average Grant Date Fair Value	'	'	'	'	'
Balance at the beginning of the period (in dollars per share)	$3.33	'	'	'	'
Granted (in dollars per share)	$10.28	'	'	'	'
Exercised (in dollars per share)	$2.39	'	'	'	'
Expired (in dollars per share)	$3.39	'	'	'	'
Forfeited (in dollars per share)	$4.60	'	'	'	'
Balance at the end of the period (in dollars per share)	$3.99	$3.33	'	'	'
Exercisable options (in dollars per share)	$2.79	'	'	'	'
Vested and expected to vest (in dollars per share)	$3.85	'	'	'	'
Weighted Average Exercise Price	'	'	'	'	'
Balance at the beginning of the period (in dollars per share)	$5.56	'	'	'	'
Granted (in dollars per share)	$13.63	'	'	'	'
Exercised (in dollars per share)	$4.14	'	'	'	'
Expired (in dollars per share)	$5.62	'	'	'	'
Forfeited (in dollars per share)	$7.33	'	'	'	'
Balance at the end of the period (in dollars per share)	$6.36	$5.56	'	'	'
Exercisable options at the end of the period (in dollars per share)	$4.65	'	'	'	'
Vested and expected to vest (in dollars per share)	$6.19	'	'	'	'
Weighted-Average Remaining Contractual Life	'	'	'	'	'
Outstanding options	'6 years 8 months 12 days	'7 years 2 months 12 days	'	'	'
Exercisable options	'5 years 6 months	'	'	'	'

Redeemable_Convertible_Preferr5

Redeemable Convertible Preferred Stock and Stockholders' Deficit (Details 4) (Stock Options, USD $)	9 Months Ended
	Sep. 30, 2013
Options Outstanding	'
Number of Underlying Shares	4,949,565
Options Exercisable	'
Number of Underlying Shares	3,061,051
0.26-1.30	'
Redeemable Convertible Preferred Stock and Stockholders' Deficit	'
Range of Exercise Price, low end of range (in dollars per share)	$0.26
Range of Exercise Price, high end of range (in dollars per share)	$1.30
Options Outstanding	'
Weighted Average Exercise Price (in dollars per share)	$0.56
Number of Underlying Shares	190,939
Weighted-Average Remaining Contractual Life	'1 year 2 months 12 days
Options Exercisable	'
Number of Underlying Shares	190,939
Weighted-Average Remaining Contractual Life	'1 year 2 months 12 days
1.35-2.60	'
Redeemable Convertible Preferred Stock and Stockholders' Deficit	'
Range of Exercise Price, low end of range (in dollars per share)	$1.35
Range of Exercise Price, high end of range (in dollars per share)	$2.60
Options Outstanding	'
Weighted Average Exercise Price (in dollars per share)	$2.18
Number of Underlying Shares	473,347
Weighted-Average Remaining Contractual Life	'2 years 8 months 12 days
Options Exercisable	'
Number of Underlying Shares	473,347
Weighted-Average Remaining Contractual Life	'2 years 8 months 12 days
2.65-3.90	'
Redeemable Convertible Preferred Stock and Stockholders' Deficit	'
Range of Exercise Price, low end of range (in dollars per share)	$2.65
Range of Exercise Price, high end of range (in dollars per share)	$3.90
Options Outstanding	'
Weighted Average Exercise Price (in dollars per share)	$3.23
Number of Underlying Shares	325,523
Weighted-Average Remaining Contractual Life	'3 years 9 months 18 days
Options Exercisable	'
Number of Underlying Shares	325,523
Weighted-Average Remaining Contractual Life	'3 years 9 months 18 days
3.95-5.20	'
Redeemable Convertible Preferred Stock and Stockholders' Deficit	'
Range of Exercise Price, low end of range (in dollars per share)	$3.95
Range of Exercise Price, high end of range (in dollars per share)	$5.20
Options Outstanding	'
Weighted Average Exercise Price (in dollars per share)	$4.87
Number of Underlying Shares	954,522
Weighted-Average Remaining Contractual Life	'5 years 6 months
Options Exercisable	'
Number of Underlying Shares	926,448
Weighted-Average Remaining Contractual Life	'5 years 6 months
5.25-6.50	'
Redeemable Convertible Preferred Stock and Stockholders' Deficit	'
Range of Exercise Price, low end of range (in dollars per share)	$5.25
Range of Exercise Price, high end of range (in dollars per share)	$6.50
Options Outstanding	'
Weighted Average Exercise Price (in dollars per share)	$6.19
Number of Underlying Shares	1,734,885
Weighted-Average Remaining Contractual Life	'8 years
Options Exercisable	'
Number of Underlying Shares	933,316
Weighted-Average Remaining Contractual Life	'7 years 10 months 24 days
6.55-7.80	'
Redeemable Convertible Preferred Stock and Stockholders' Deficit	'
Range of Exercise Price, low end of range (in dollars per share)	$6.55
Range of Exercise Price, high end of range (in dollars per share)	$7.80
Options Outstanding	'
Weighted Average Exercise Price (in dollars per share)	$7.49
Number of Underlying Shares	118,947
Weighted-Average Remaining Contractual Life	'6 years 9 months 18 days
Options Exercisable	'
Number of Underlying Shares	95,260
Weighted-Average Remaining Contractual Life	'6 years 9 months 18 days
7.85-9.10	'
Redeemable Convertible Preferred Stock and Stockholders' Deficit	'
Range of Exercise Price, low end of range (in dollars per share)	$7.85
Range of Exercise Price, high end of range (in dollars per share)	$9.10
Options Outstanding	'
Weighted Average Exercise Price (in dollars per share)	$8.84
Number of Underlying Shares	239,893
Weighted-Average Remaining Contractual Life	'8 years 8 months 12 days
Options Exercisable	'
Number of Underlying Shares	81,075
Weighted-Average Remaining Contractual Life	'8 years 8 months 12 days
9.15-22.77	'
Redeemable Convertible Preferred Stock and Stockholders' Deficit	'
Range of Exercise Price, low end of range (in dollars per share)	$9.15
Range of Exercise Price, high end of range (in dollars per share)	$22.77
Options Outstanding	'
Weighted Average Exercise Price (in dollars per share)	$11.40
Number of Underlying Shares	911,509
Weighted-Average Remaining Contractual Life	'8 years 10 months 24 days
Options Exercisable	'
Number of Underlying Shares	35,143
Weighted-Average Remaining Contractual Life	'9 years 1 month 6 days

Redeemable_Convertible_Preferr6

Redeemable Convertible Preferred Stock and Stockholders' Deficit (Details 5) (Stock options, USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Intrinsic-value	'	'	'	'
Options Exercised	'	'	$1,130	'
Options Outstanding	55,147	'	55,147	'
Options Exercisable	$38,783	'	$38,783	'
Assumptions used to estimate fair value of stock options	'	'	'	'
Expected volatility (as a percent)	57.00%	61.00%	'	'
Expected volatility, minimum (as a percent)	'	'	56.00%	61.00%
Expected volatility, maximum (as a percent)	'	'	59.00%	63.00%
Expected dividends (as a percent)	0.00%	0.00%	0.00%	0.00%
Risk-free rate (as a percent)	'	0.80%	'	'
Risk-free rate, minimum (as a percent)	1.50%	'	0.80%	0.80%
Risk-free rate, maximum (as a percent)	1.70%	'	1.70%	0.90%
Forfeiture rate (as a percent)	7.20%	7.90%	7.20%	7.90%
Minimum	'	'	'	'
Assumptions used to estimate fair value of stock options	'	'	'	'
Expected term	'5 years 6 months	'6 years	'3 years 3 months 18 days	'5 years 6 months
Maximum	'	'	'	'
Assumptions used to estimate fair value of stock options	'	'	'	'
Expected term	'6 years 1 month 6 days	'6 years 1 month 6 days	'7 years 2 months 12 days	'6 years 1 month 6 days

Redeemable_Convertible_Preferr7

Redeemable Convertible Preferred Stock and Stockholders' Deficit (Details 6) (Stock options, USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Total stock-based compensation expense	'	'	'	'
Total stock-based compensation expense	$940,000	$722,000	$2,648,000	$2,094,000
Total unrecognized compensation cost related to non-vested stock option awards	8,100,000	'	8,100,000	'
Weighted-average period over which unrecognized compensation cost will be recognized	'	'	'3 years 1 month 6 days	'
Cost of revenue	'	'	'	'
Total stock-based compensation expense	'	'	'	'
Total stock-based compensation expense	15,000	18,000	46,000	53,000
Research and development	'	'	'	'
Total stock-based compensation expense	'	'	'	'
Total stock-based compensation expense	419,000	202,000	974,000	461,000
Sales and marketing	'	'	'	'
Total stock-based compensation expense	'	'	'	'
Total stock-based compensation expense	187,000	139,000	543,000	421,000
General and administrative	'	'	'	'
Total stock-based compensation expense	'	'	'	'
Total stock-based compensation expense	$319,000	$363,000	$1,085,000	$1,159,000

Related_Party_Transactions_Det

Related Party Transactions (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Related Party Transactions	'	'	'	'	'
Revenue from product sales	$960,000	$1,698,000	$3,358,000	$4,303,000	'
Accounts receivable	800,000	'	800,000	'	1,500,000
Investors | Company 1	'	'	'	'	'
Related Party Transactions	'	'	'	'	'
Revenue from product sales	694,000	747,000	2,059,000	1,567,000	'
Investors | Company 2	'	'	'	'	'
Related Party Transactions	'	'	'	'	'
Revenue from product sales	'	211,000	128,000	813,000	'
Investors | Company 3	'	'	'	'	'
Related Party Transactions	'	'	'	'	'
Revenue from product sales	262,000	372,000	748,000	1,139,000	'
Investors | Company 4	'	'	'	'	'
Related Party Transactions	'	'	'	'	'
Revenue from product sales	$4,000	$368,000	$423,000	$784,000	'

Commitments_and_Contingencies_1

Commitments and Contingencies (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Operating Leases	'	'	'	'
Rental expense	$300,000	$300,000	$1,000,000	$700,000
Future minimum rental payments	'	'	'	'
2013	370,000	'	370,000	'
2014	1,452,000	'	1,452,000	'
2015	1,451,000	'	1,451,000	'
2016	1,312,000	'	1,312,000	'
2017	1,124,000	'	1,124,000	'
Thereafter	557,000	'	557,000	'
Total	6,266,000	'	6,266,000	'
Purchase Commitments	'	'	'	'
Non-cancellable purchase commitments	$23,900,000	'	$23,900,000	'
Minimum	'	'	'	'
Operating Leases	'	'	'	'
Extension term of leases	'	'	'3 years	'
Maximum	'	'	'	'
Operating Leases	'	'	'	'
Extension term of leases	'	'	'5 years	'