Calix (CALX) 10-K 20 Feb 14 2013 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2012	Feb. 12, 2014	Jun. 28, 2013
Document and Entity Information [Abstract]	'	'	'
Entity Registrant Name	'CALIX, INC	'	'
Entity Central Index Key	'0001406666	'	'
Document Type	'10-K	'	'
Document Period End Date	31-Dec-13	'	'
Amendment Flag	'false	'	'
Document Fiscal Year Focus	'2013	'	'
Document Fiscal Period Focus	'FY	'	'
Current Fiscal Year End Date	'--12-31	'	'
Entity Filer Category	'Accelerated Filer	'	'
Entity Current Reporting Status	'Yes	'	'
Entity Voluntary Filers	'No	'	'
Entity Well-known Seasoned Issuer	'No	'	'
Trading Symbol	'calx	'	'
Entity Common Stock, Shares Outstanding	'	50,224,952	'
Entity Public Float	'	'	$409.40

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Current Assets:	'	'
Cash and cash equivalents	$82,747	$46,995
Restricted cash	295	0
Accounts receivable, net	43,520	59,519
Inventory	51,071	43,282
Deferred cost of revenue	21,076	21,077
Prepaid and other current assets	5,757	5,677
Total current assets	204,466	176,550
Property and equipment, net	17,473	21,083
Goodwill	116,175	116,175
Intangible assets, net	43,740	62,301
Other assets	1,745	1,788
Total assets	383,599	377,897
Current liabilities:	'	'
Accounts payable	23,163	16,804
Accrued liabilities	32,075	36,176
Deferred revenue	34,862	39,315
Total current liabilities	90,100	92,295
Long-term portion of deferred revenue	18,431	15,782
Other long-term liabilities	1,145	745
Total liabilities	109,676	108,822
Commitments and contingencies (See Note 5)	'	'
Stockholders' equity:	'	'
Preferred stock, $0.025 par value; 5,000,000 shares authorized; no shares issued and outstanding as of December 31, 2012 and December 31, 2011	0	0
Common stock, $0.025 par value; 100,000,000 shares authorized; 48,898,924 shares and 47,825,200 shares issued and outstanding as of December 31, 2012 and December 31, 2011, respectively	1,256	1,222
Additional paid-in capital	782,253	760,232
Accumulated other comprehensive income	190	132
Accumulated deficit	-509,776	-492,511
Total stockholders' equity	273,923	269,075
Total liabilities and stockholders' equity	$383,599	$377,897

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Statement of Financial Position [Abstract]	'	'
Preferred stock, par value	$0.03	$0.03
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$0.03	$0.03
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	50,224,952	48,898,924
Common stock, shares outstanding	50,224,952	48,898,924

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Loss (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Income Statement [Abstract]	'		'		'
Revenue	$382,618		$330,218		$344,669
Cost of revenue:	'		'		'
Products and services	203,191	[1]	185,103	[1]	195,698	[1]
Acquisition-related expenses	0		0		19,966
Amortization of intangible assets	8,353		7,539		9,552
Total cost of revenue	211,544		192,642		225,216
Gross profit	171,074		137,576		119,453
Operating expenses:	'		'		'
Research and development	79,299	[1]	66,748	[1]	67,725	[1]
Sales and marketing	68,075	[1]	62,129	[1]	55,551	[1]
General and administrative	31,945	[1]	26,114	[1]	27,002	[1]
Amortization of intangible assets	10,208		10,208		8,569
Acquisition-related Expenses	0	[1]	1,401	[1]	12,927	[1]
Total operating expenses	189,527		166,600		171,774
Loss from operations	-18,453		-29,024		-52,321
Interest and other income (expense), net:	'		'		'
Interest income	7		15		87
Interest expense	-167		-185		-184
Utilization of inventory credit	1,651		0		0
Gain on bargain purchase	0		1,029		0
Other income (expense), net	-317		-3		92
Total interest and other income (expense), net	1,174		856		-5
Loss before provision for (benefit from) income taxes	-17,279		-28,168		-52,326
Provision for (benefit from) income taxes	-14		158		224
Net loss	-17,265		-28,326		-52,550
Net loss per common share:	'		'		'
Basic and diluted (Per Share)	($0.35)		($0.59)		($1.15)
Weighted-average number of shares used to compute net loss per common share:	'		'		'
Basic and diluted (Shares)	49,419		48,180		45,546
Other comprehensive income, net of tax:	'		'		'
Unrealized loss on investments, net	0		0		-21
Foreign currency translation adjustments, net	58		34		88
Total other comprehensive income, net of tax	58		34		67
Comprehensive loss	($17,207)		($28,292)		($52,483)
[1]	Includes stock-based compensation as follows (in thousands): Years Ended December 31, 2013, 2012, and 2011;Cost of revenue: $1,468, $1,433, $1,503;Research and development: $4,896, $4,227, $4,828;Sales and marketing: $5,577, $5,160, $4,500;General administrative: $7,980, $6,617, $9,538;Acquisition-related expenses: $0, $0, $1,234;Total: $19,921, $17,437, $21,603.

Consolidated_Statements_of_Com1

Consolidated Statements of Comprehensive Loss (Parenthetical) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Stock based compensation	$19,921	$17,437	$21,603
Cost of revenue [Member]	'	'	'
Stock based compensation	1,468	1,433	1,503
Research and development [Member]	'	'	'
Stock based compensation	4,896	4,227	4,828
Sales and marketing [Member]	'	'	'
Stock based compensation	5,577	5,160	4,500
General and administrative [Member]	'	'	'
Stock based compensation	7,980	6,617	9,538
Acquisition-related expenses [Member]	'	'	'
Stock based compensation	$0	$0	$1,234

Conoslidated_Statements_of_Sto

Conoslidated Statements of Stockholders' Equity (USD $)	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Accumulated deficit [Member]
In Thousands, except Share data, unless otherwise specified
Beginning Balance at Dec. 31, 2010	$195,303	$968	$605,939	$31	($411,635)
Beginning Balance, shares at Dec. 31, 2010	'	38,712,000	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'
Stock-based compensation	21,603	'	21,603	'	'
Stock Issued for Occam Acquisition, shares	6,359,000	'	'	'	'
Acquisition of Occam networks	118,628	159	118,469	'	'
Exercise of stock options and warrants, shares	'	207,000	'	'	'
Exercise of stock options and warrants	804	5	799	'	'
issuance of vested restricted stock units, net of taxes withheld, shares	'	1,703,000	'	'	'
Issuance of vested restricted stock units, net of taxes withheld	-10,376	42	-10,418	'	'
Restricted stock awards issued, shares	'	423,000	'	'	'
Restricted stock awards issued	0	11	-11	'	'
Stock issued under employee stock purchase plan, shares	'	421,000	'	'	'
Stock issued under employee stock purchase plan	3,938	10	3,928	'	'
Net loss	-52,550	'	'	'	-52,550
Other comprehensive income	67	'	'	67	'
Ending Balance at Dec. 31, 2011	277,417	1,195	740,309	98	-464,185
Ending Balance, shares at Dec. 31, 2011	'	47,825,000	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'
Stock-based compensation	17,437	'	17,437	'	'
Exercise of stock options and warrants, shares	'	115,000	'	'	'
Exercise of stock options and warrants	194	3	191	'	'
issuance of vested restricted stock units, net of taxes withheld, shares	'	400,000	'	'	'
Issuance of vested restricted stock units, net of taxes withheld	-1,554	10	-1,564	'	'
Stock issued under employee stock purchase plan, shares	'	619,000	'	'	'
Stock issued under employee stock purchase plan	4,063	16	4,047	'	'
Shares withheld for taxes for vested restricted stock awards, shares	'	-35,000	'	'	'
Shares withheld for taxes for vested restricted stock awards	-190	-1	-189	'	'
Restricted stock awards forfeited, shares	'	-25,000	'	'	'
Restricted stock awards forfeited	0	-1	1	'	'
Net loss	-28,326	'	'	'	-28,326
Other comprehensive income	34	'	'	34	'
Ending Balance at Dec. 31, 2012	269,075	1,222	760,232	132	-492,511
Ending Balance, shares at Dec. 31, 2012	48,898,924	48,899,000	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'
Stock-based compensation	19,921	'	19,921	'	'
Exercise of stock options and warrants, shares	160,000	160,000	'	'	'
Exercise of stock options and warrants	747	4	743	'	'
issuance of vested restricted stock units, net of taxes withheld, shares	'	529,000	'	'	'
Issuance of vested restricted stock units, net of taxes withheld	-3,031	14	-3,045	'	'
Stock issued under employee stock purchase plan, shares	685,781	685,781	'	'	'
Stock issued under employee stock purchase plan	4,828	17	4,811	'	'
Shares withheld for taxes for vested restricted stock awards, shares	'	-34,000	'	'	'
Shares withheld for taxes for vested restricted stock awards	-410	-1	-409	'	'
Restricted stock awards forfeited, shares	'	-15,000	'	'	'
Restricted stock awards forfeited	0	0	0	'	'
Net loss	-17,265	'	'	'	-17,265
Other comprehensive income	58	'	'	58	'
Ending Balance at Dec. 31, 2013	$273,923	$1,256	$782,253	$190	($509,776)
Ending Balance, shares at Dec. 31, 2013	50,224,952	50,225,000	'	'	'

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating activities:	'	'	'
Net loss	($17,265)	($28,326)	($52,550)
Adjustments to reconcile net loss to net cash provided by operating activities:	'	'	'
Amortization of premiums relating to available-for-sale securities	0	0	244
Depreciation and amortization	10,181	8,562	7,954
Loss on retirement of property and equipment	569	262	2,449
Amortization of intangible assets	18,561	17,747	18,121
Stock-based compensation	19,921	17,437	21,603
Utilization of inventory credit	-1,651	0	0
Gain on bargain purchase	0	-1,029	0
Changes in operating assets and liabilities:	'	'	'
Restricted cash	-295	754	300
Accounts receivable, net	15,999	-13,011	13,722
Inventory	-6,138	11,308	8,557
Deferred cost of revenue	1	-13,379	73
Prepaids and other assets	535	47	-148
Accounts payable	6,359	2,554	-7,818
Accrued liabilities	-4,217	-869	-386
Deferred revenue	-1,804	26,403	2,781
Other long-term liabilities	62	-782	-313
Net cash provided by operating activities	40,818	27,678	14,589
Investing activities:	'	'	'
Purchase of property and equipment	-6,987	-10,179	-7,355
Sales and maturities of marketable securities	0	0	31,755
Acquisitions, net of cash acquired	0	-12,000	-60,809
Net cash used in investing activities	-6,987	-22,179	-36,409
Financing activities:	'	'	'
Proceeds from exercise of stock options and other	747	194	804
Proceeds from employee stock purchase plan	4,828	4,063	3,938
Taxes withheld upon vesting of restricted stock units and restricted stock awards	-3,441	-1,744	-10,376
Payments for debt issuance costs	-316	'	'
Net cash provided by (used in) financing activities	1,818	2,513	-5,634
Effect of exchange rate changes on cash and cash equivalents	103	45	88
Net increase (decrease) in cash and cash equivalents	35,752	8,057	-27,366
Cash and cash equivalents at beginning of period	46,995	38,938	66,304
Cash and cash equivalents at end of period	82,747	46,995	38,938
Supplemental disclosures of cash flow information	'	'	'
Interest paid	57	68	87
Income taxes paid	96	125	79
Non-cash financing and investing activities:	'	'	'
Property and equipment acquired using credits from Ericsson Inc.	125	'	'
Value of common stock issued in acquisition	'	'	117,258
Fair value of equity awards assumed in connection with acquisition	'	'	$1,370

Description_of_Business_and_Si

Description of Business and Significant Accounting Policies (Notes)	12 Months Ended
	Dec. 31, 2013
DescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesAbstract [Abstract]	'
Description of Business and Significant Accounting Policies	'
	1	Description of Business and Significant Accounting Policies
	Company
	Calix, Inc. (together with its subsidiaries, “Calix,” the “Company,” “our,” “we,” or “us”) was incorporated in August 1999, and is a Delaware corporation. The Company is a leading provider in North America of broadband communications access systems and software for fiber- and copper-based network architectures that enable communications service providers ("CSPs") to transform their networks and connect to their residential and business subscribers. The Company enables CSPs to provide a wide range of revenue-generating services, from basic voice and data to advanced broadband services, over legacy and next-generation access networks. The Company focuses solely on CSP access networks, the portion of the network that governs available bandwidth and determines the range and quality of services that can be offered to subscribers. The Company develops and sells carrier-class hardware and software products, which the Company refers to as the Unified Access portfolio that are designed to enhance and transform CSP access networks to meet the changing demands of subscribers rapidly and cost-effectively.
	Basis of Presentation
	The Company's fiscal year begins on January 1st and ends on December 31st. Quarterly periods are based on a 4-4-5 fiscal calendar with the first, second and third fiscal quarters ending on the 13th Saturday of each fiscal period.
	The accompanying consolidated financial statements, including the accounts of Calix, Inc. and its wholly owned subsidiaries, have been prepared in accordance with the requirements of the U.S. Securities and Exchange Commission (“SEC”). In the opinion of management, the consolidated financial statements include all normal and recurring adjustments that are considered necessary for the fair presentation of the Company’s financial position and operating results. All significant intercompany balances and transactions have been eliminated in consolidation.
	Applicable Accounting Guidance
	Any reference in these notes to applicable accounting guidance (“guidance”) is meant to refer to the authoritative U.S. generally accepted accounting principles ("GAAP") as found in the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”).
	Use of Estimates
	The preparation of financial statements is in conformity with U.S. GAAP, which requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. For the Company, these estimates include, but are not limited to: allowances for doubtful accounts and sales returns, excess and obsolete inventory, allowances for obligations to its contract manufacturers, valuation of stock-based compensation, useful lives assigned to long-lived assets and acquired intangible assets, warranty costs, and contingencies. Actual results could differ from those estimates, and such differences could be material to the Company's financial position and results of operations.
	Business Combination
	The Company accounted for its business acquisitions under ASC Topic 805, “Business Combinations” ("ASC Topic 805"). Under this guidance all of the assets acquired and liabilities assumed are recognized at their fair value as of the acquisition date. The excess of the purchase price over the estimated fair values of the net tangible and intangible assets acquired is recorded as goodwill. If a business combination results in a bargain purchase for the Company, the economic gain resulting from the fair value received being greater than the purchase price is recorded as a gain that is included in other income (expense), net in the Consolidated Statements of Comprehensive Loss. Prior to recognizing the gain, the Company reassesses whether it has correctly identified all of the assets acquired and liabilities assumed and recognizes any additional assets or liabilities that result from that review. The Company also reviews the measurement procedures used in valuing the assets acquired and liabilities assumed.
	While the Company uses its best estimates and assumptions as a part of calculating the fair value at the acquisition date, the Company's estimates are inherently uncertain and subject to refinement. As a result, during the measurement period, which maybe up to one year from the acquisition date, the Company may record adjustments retrospectively to the fair value of assets acquired and liabilities assumed, with the corresponding offset to goodwill, or records a corresponding other income or expense in the case of a bargain purchase. Upon the conclusion of the measurement period or final determination of the fair value of assets acquired or liabilities assumed, whichever comes first, any subsequent adjustments are recorded to the Company's Consolidated Statements of Comprehensive Loss.
	Transaction costs associated with the business combinations are expensed as incurred, and are included in acquisition-related expenses within operating expenses in the Consolidated Statements of Comprehensive Loss.
	Revenue Recognition
	The Company derives revenue primarily from the sale of hardware products and related software. Revenue is recognized when all of the following criteria have been met:
	•	Persuasive evidence of an arrangement exists.   The Company generally relies upon sales agreements and customer purchase orders as evidence of an arrangement.
	•	Delivery has occurred.  The Company uses the shipping terms of the arrangement or evidence of customer acceptance to verify delivery or performance.
	•	Sales price is fixed or determinable.   The Company assesses whether the sales price is fixed or determinable based on the payment terms and whether the sales price is subject to refund or adjustment. Payment terms to customers can range from net 30 to net 120 days.
	•	Collectability is reasonably assured.  The Company assesses collectability based primarily on creditworthiness of customers and their payment histories.
	Revenue from installation and training services are recognized as the services are completed. Post-sales software support revenue and extended warranty services revenue are deferred and recognized ratably over the period during which the services are to be performed. To date, service revenue has comprised an insignificant portion of the Company's revenue and the Company has not reported service revenue separately from product revenue in its financial statements. In instances where substantive acceptance provisions are specified in the customer agreement, revenue is deferred until all acceptance criteria have been met. From time to time, the Company offers customers sales incentives, which include volume rebates and discounts. These amounts are estimated on a quarterly basis and recorded as a reduction of revenue.
	The Company enters into arrangements with certain of its customers who receive government supported loans and grants from the U.S. Department of Agriculture's Rural Utility Service (“RUS”) to finance capital spending. Under the terms of an RUS equipment contract that includes installation services, the customer does not take possession and control and title does not pass until formal acceptance is obtained from the customer. Under this type of arrangement, the Company does not recognize revenue until it has received formal acceptance from the customer. For RUS arrangements that do not involve installation services, the Company recognizes revenue in accordance with the revenue recognition policy described above.
	The Company's products contain both software and non-software components that function together to deliver the products' essential functionality. When the Company enters into sales arrangements that consist of multiple deliverables of its product and service offerings, the Company allocates the total consideration of the arrangement to each separable deliverable based on its relative selling price. The Company limits the amount allocable to delivered elements to the amount that is not contingent upon the delivery of additional items or meeting specified performance conditions, and recognizes revenue on each deliverable in accordance with its revenue recognition policy. The determination of selling price for each deliverable is based on a selling price hierarchy, which is vendor-specific objective evidence (“VSOE”) if available, third-party evidence (“TPE”) if VSOE is not available, or estimated selling price (“ESP”) if neither VSOE nor TPE is available. VSOE of selling price is based on the price charged when the element is sold separately. In determining VSOE, the Company requires that a substantial majority of the selling prices of an element fall within a narrow range when each element is sold separately. The Company has established VSOE for its training and post-sales software support services based on the normal pricing practices of these services when sold separately. TPE of selling price is established by evaluating whether there are similar competitor products or services that are sold in stand-alone sales transaction to similarly situated customers. Generally, the Company's marketing strategy differs from that of its peers and its offerings contain a significant level of customization and differentiation such that the comparable pricing of products with similar functionality cannot be obtained. Additionally, as the Company is unable to reliably determine what similar competitor products' selling prices are on a stand-alone basis, it is not typically able to determine TPE. ESP is established considering multiple factors including, but not limited to geographies market conditions, competitive landscape, internal costs, gross margin objectives, characteristics of targeted customers and pricing practices. The determination of ESP is made through consultation with and formal approval by management, taking into consideration the go-to-market strategy.
	Cost of Revenue
	Cost of revenue consists primarily of finished goods inventory purchased from the Company’s contract manufacturers, payroll and related expenses associated with managing the relationships with contract manufacturers, depreciation of manufacturing test equipment, warranty costs, excess and obsolete inventory costs, shipping charges, and amortization of certain intangible assets. For the year ended December 31, 2011, cost of revenue also includes acquisition-related expenses associated with the acquisition of Occam primarily related to a charge resulting from the required revaluation of Occam inventory to its estimated fair value and an associated write-down of acquired inventory determined as excess and obsolete.
	Stock-Based Compensation
	In accordance with ASC Topic 718, "Compensation - Stock Compensation" ("ASC Topic 718"), stock-based awards are recorded at fair value as of the grant date and recognized to expense over the employee’s requisite service period (generally the vesting period), which the Company has elected to amortize on a straight-line basis. Stock-based compensation expense is reduced by the Company’s estimated forfeitures on all unvested awards.
	The fair value of stock option and employee stock purchase right is estimated at the grant date using the Black-Scholes option valuation model. The fair value of restricted stock unit and restricted stock award is based on the closing market price of the Company's common stock on the date of grant. The fair value of performance restricted stock unit ("PRSU") with a market condition is estimated on the date of grant, using a Monte Carlo simulation model to estimate the total return ranking of the Company's stock in relation to the peer group over each performance period. Compensation cost on PRSUs with a market condition is not adjusted for subsequent changes in the Company's stock performance or the level of ultimate vesting.
	Warranty
	The Company offers limited warranties for its hardware products for a period of one or five years, depending on the product type. Warranty service revenues are deferred and recognized ratably over the period during which the services are to be performed. The Company recognizes estimated costs related to warranty activities as a component of cost of revenue upon product shipment. The estimates are based on historical product failure rates and historical costs incurred in correcting product failures. The recorded amount is adjusted from time to time for specifically identified warranty exposure. Actual warranty expenses are charged against the Company’s estimated warranty liability when incurred. Factors that affect the Company’s warranty liability include the number of installed units and historical and anticipated rates of warranty claims and cost per claim.
	Research and Development
	Research and development costs include costs of developing new products and processes, as well as design and engineering costs. Such costs are charged to research and development expense as incurred.
	Development costs related to software incorporated in the Company’s products incurred subsequent to the establishment of technological feasibility are capitalized and amortized over the estimated useful lives of the related products. Technological feasibility is established upon completion of a working model.
	Credit Risk and Inventory Supplier Concentrations
	Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash and cash equivalents and accounts receivable. Cash equivalents consist of money market funds, which are invested through financial institutions in the United States. Deposits in these financial institutions may, at times, exceed federally insured limits. The Company has not experienced any losses in such accounts. The Company also has approximately $2.8 million of cash held by its foreign subsidiaries in China and the United Kingdom. Management believes that the financial institutions that hold the Company’s cash and cash equivalents are financially sound and, accordingly, minimal credit risk exists with respect to these cash and cash equivalents.
	Concentrations of credit risk in relation to customers with an accounts receivable balance of 10% or greater of total accounts receivable and customers with net revenues of 10% or greater of total revenues are presented below for the periods indicated.
			Percentage of Accounts Receivable		Percentage of Revenue
			At December 31,		Years Ended December 31,
			2013	2012	2013	2012	2011
	CenturyLink		15%	13%	26%	21%	20%
	Ericsson (1)		12%	*	*	*	*
	(1) Includes certain of Ericsson's consolidated subsidiaries.
	* Less than 10% of total accounts receivable or revenue.
	The Company maintains an allowance for doubtful accounts for estimated losses resulting from the inability of its customers to make required payments. The Company records a specific allowance based on an analysis of individual past-due balances. Additionally, based on its historical write-offs and collections experience, the Company records an additional allowance based on a percentage of outstanding receivables. The Company performs credit evaluations of its customers’ financial condition. These evaluations require significant judgment and are based on a variety of factors including, but not limited to, current economic trends, payment history and financial review of the customer. Actual collection losses may differ from management’s estimates, and such differences could be material to the Company’s financial position and results of operations.
	The Company depends primarily on a small number of outside contract manufacturers for the bulk of its finished goods inventory. In particular, the Company relies on Flextronics for the manufacture of most of its products. The Company generally purchases its products through purchase orders with its suppliers or contract manufacturers. While the Company seeks to maintain a sufficient reserve of its products, the Company’s business and results of operations could be adversely affected by a stoppage or delay in receiving such products, the receipt of defective parts, an increase in price of such products or the Company’s inability to obtain lower prices from its contract manufacturers and suppliers in response to competitive pressures.
	Fair Value of Financial Instruments
	The carrying amounts of cash and cash equivalents, trade receivables, marketable securities, accounts payable, and other accrued liabilities approximate their fair value due to their relatively short-term nature. The carrying amount of the other long-term liabilities approximates its fair value.
	Cash, Cash Equivalents, and Marketable Securities
	The Company has invested its excess cash primarily in money market funds in 2013 and 2012. Before 2012, the Company also invested some cash in highly liquid debt instruments. The Company considers all investments with maturities of three months or less when purchased to be cash equivalents. Marketable securities represent highly liquid debt instruments with maturities greater than 90 days at date of purchase. Cash, cash equivalents and marketable securities are stated at amounts that approximate fair value based on quoted market prices.
	The Company’s investments have been classified and accounted for as available-for-sale. Such investments are recorded at fair value and unrealized holding gains and losses are reported as a separate component of comprehensive loss in the stockholders’ equity until realized. Should the Company determine that any unrealized losses on the investments are other-than-temporary, the amount of that impairment to be recognized in earnings will depend on whether the Company intends to sell the security or more likely than not will be required to sell the security before recovery of its amortized cost basis less any current period credit loss. During 2011, all of the Company's marketable securities had been sold or matured. Realized gains and losses, which have been immaterial, are determined on the specific identification method and are reflected in results of operations.
	Restricted Cash
	As of December 31, 2013, the Company had $0.3 million cash restricted for collateralizing the outstanding letters of credit with Silicon Valley Bank. As of December 31, 2012, there were no restricted cash balances.
	Inventory
	Inventory, which primarily consisted of finished goods purchased from contract manufacturers, is stated at the lower of cost, determined by the first-in, first-out method, or market value. Inbound shipping costs are included in cost of inventory. In addition, the Company, from time to time, procures component inventory primarily as a result of manufacturing discontinuation of critical components by suppliers. The Company regularly monitors inventory quantities on hand and records write-downs for excess and obsolete inventories based on the Company’s estimate of demand for its products, potential obsolescence of technology, product life cycles, and whether pricing trends or forecasts indicate that the carrying value of inventory exceeds its estimated selling price. These factors are impacted by market and economic conditions, technology changes, and new product introductions and require estimates that may include elements that are uncertain. Actual demand may differ from forecasted demand and may have a material effect on gross margins. If inventory is written down, a new cost basis is established that cannot be increased in future periods. Shipments from our suppliers or contract manufacturers before the Company receives them are recorded as in-transit inventory when title and the significant risks and rewards of ownership have passed to the Company.
	Deferred Cost of Revenue
	When the Company’s products have been shipped, but the product revenue associated with the arrangement has been deferred as a result of not meeting the criteria for immediate revenue recognition, the Company also defers the related inventory costs for the delivered items until all criteria are met for revenue recognition. Deferred cost of revenue also includes installation service costs related to customer installation projects in which the revenue has been deferred until completion of the project and, to a lesser extent, trial orders that are pending acceptance.
	Property and Equipment
	Property and equipment are stated at cost, less accumulated depreciation, and are depreciated using the straight-line method over the estimated useful life of each asset. Computer equipment is depreciated over two years; purchased software is depreciated over three years; test equipment is depreciated over three years; furniture and fixtures are depreciated over seven years; and leasehold improvements are depreciated over the shorter of the respective lease term or the estimated useful life of the asset. Maintenance and repairs are charged to expense as incurred.
	Goodwill
	The Company records goodwill when consideration paid in a business acquisition exceeds the fair value of the net tangible assets and the identified intangible assets acquired. Goodwill is not amortized but instead is subject to an annual impairment test or more frequently if events or changes in circumstances indicate that it may be impaired. The Company evaluates goodwill on an annual basis as of the end of the second quarter of each fiscal year. Management has determined that it operates as a single reporting unit and, therefore, evaluates goodwill impairment at the enterprise level.
	In an annual impairment test, the Company first assesses qualitative factors to determine whether it is necessary to perform the two-step quantitative goodwill impairment test. In assessing the qualitative factors, management considers the impact of these key factors: macro-economic conditions, industry and market environment, overall financial performance of the Company, cash flow from operating activities, market capitalization and stock price. If the Company determines as a result of the qualitative assessment that it is more likely than not that the fair value of a reporting unit is less than its carrying amount, then the quantitative test is required. Otherwise, no further testing is required.
	In a quantitative test, the Company compares its fair value to its carrying value including goodwill. The Company determines its fair value using both an income approach and a market approach. Under the income approach, the Company determines fair value based on estimated future cash flows, discounted by an estimated weighted-average cost of capital, which reflects the overall level of inherent risk of the Company and the rate of return an outside investor would expect to earn. Under the market-based approach, the Company utilizes information regarding the Company as well as publicly available industry information to determine earnings multiples that are used to value the Company. If the carrying value of the Company exceeds its fair value, the Company will determine the amount of impairment loss by comparing the implied fair value of goodwill with the carrying value of goodwill. An impairment charge is recognized for the excess of the carrying value of goodwill over its implied fair value.
	At the end of the second quarter of 2013, the Company has completed its annual goodwill impairment test. Based on its assessment of the aforementioned qualitative factors, management concluded that the fair value of the Company was more likely than not greater than its carrying amount as of June 29, 2013. As such, it was not necessary to perform the two-step quantitative goodwill impairment test at the time. Subsequent to the 2013 annual impairment test, there have been no significant events or circumstances affecting the valuation of goodwill. As of December 31, 2013, there was no impairment to the carrying value of the Company's goodwill. There were no impairment losses for goodwill during 2012 and 2011.
Intangible Assets and Other Long-Lived Assets
Intangible assets with finite useful lives are amortized over their estimated useful life, generally five years. The Company periodically evaluates long-lived assets, including intangible assets, for impairment whenever events or changes in circumstances indicate that a potential impairment may have occurred. If such events or changes in circumstances arise, the Company compares the carrying amount of the long-lived assets to the estimated future undiscounted cash flows expected to be generated by the long-lived assets. If the estimated aggregate undiscounted cash flows are less than the carrying amount of the long-lived assets, an impairment charge, calculated as the amount by which the carrying amount of the assets exceeds the fair value of the assets, is recorded. The fair value of long-lived assets is determined based on the estimated discounted cash flows expected to be generated from the assets. The Company has reviewed events and changes to its business during the year and has determined that there was no impairment to its intangible assets and other long-lived assets during 2013. The Company did not incur any impairment losses for intangible assets and other long-lived assets during 2012 and 2011.
Income Taxes
The Company evaluates its tax positions and estimates its current tax exposure along with assessing temporary differences that result from different book to tax treatment of items not currently deductible for tax purposes. These differences result in deferred tax assets and liabilities on the Company’s balance sheets, which are estimated based upon the difference between the financial statement and tax bases of assets and liabilities using the enacted tax rates that will be in effect when these differences reverse. In general, deferred tax assets represent future tax benefits to be received when certain expenses previously recognized in the Company’s statements of operations become deductible expenses under applicable income tax laws or loss or credit carryforwards are utilized. Accordingly, realization of the Company’s deferred tax assets is dependent on future taxable income against which these deductions, losses and credits can be utilized.
The Company must assess the likelihood that the Company’s deferred tax assets will be recovered from future taxable income, and to the extent the Company believes that recovery is not more likely than not, the Company must establish a valuation allowance. Management judgment is required in determining the Company’s provision for income taxes, the Company’s deferred tax assets and liabilities and any valuation allowance recorded against the Company’s net deferred tax assets. Excluding our foreign operations, the Company recorded a full valuation allowance at each balance sheet date presented because, based on the available evidence, the Company believes it is more likely than not that it will not be able to utilize all of its deferred tax assets in the future. The Company intends to maintain the full valuation allowances until sufficient evidence exists to support the reversal of the valuation allowances.
Foreign Currency Translation
Assets and liabilities of the Company’s wholly owned foreign subsidiaries are translated from their respective functional currencies at exchange rates in effect at the balance sheet date, and revenues and expenses are translated at the monthly average exchanges rates. Any material resulting translation adjustments are reflected as a separate component of stockholders’ equity. Realized foreign currency transaction gains and losses were not significant during the years ended December 31, 2013, 2012 and 2011.
Recent Accounting Pronouncements
In July 2013, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update No. 2013-11, Income Taxes (Topic 740): Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists (a consensus of the FASB Emerging Issues Task Force) ("ASU 2013-11"), which provides explicit guidance on the financial statement presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss or a tax credit carryforward exists. Under the new standard update, in most circumstances, an unrecognized tax benefit should be presented in the Company's financial statements as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss or a tax credit carryforward. The amendments should be applied prospectively to all unrecognized tax benefits that exist at the effective date. Retrospective application is permitted. ASU 2013-11 will be effective for the Company beginning in the first quarter of fiscal 2014. The Company does not expect adoption of this guidance to have a material impact on its financial statements.
In February 2013, the FASB issued Accounting Standards Update No. 2013-02, Comprehensive Income (Topic 220): Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income ("ASU 2013-02"), to improve the reporting of reclassifications out of accumulated other comprehensive income. ASU 2013-02 requires an entity to report the effect of significant reclassifications out of accumulated other comprehensive income on the respective line items in net income if the amount being reclassified is required under U.S. GAAP to be reclassified in its entirety to net income. For other amounts that are not required under U.S. GAAP to be reclassified in their entirety from accumulated other comprehensive income to net income in the same reporting period, an entity is required to cross-reference other disclosures required under U.S. GAAP that provide additional detail about those amounts. ASU 2013-02 was effective for the Company in its first quarter of fiscal 2013 and was applied prospectively. Other than requiring additional disclosures, adoption of this guidance did not have an impact on the financial statements of the Company.

Business_Combinations_Notes

Business Combinations (Notes)	12 Months Ended
	Dec. 31, 2013
Business Combinations [Abstract]	'
Business Combinations	'
	2. Business Combinations
	Acquisition of Ericsson Fiber Access Assets
	On November 2, 2012, Calix acquired the fiber access assets of Ericsson Inc. ("Ericsson"), including the Ericsson EDA 1500 GPON solution and its complementary ONT portfolio, under an Asset Purchase Agreement ("EFAA Acquisition"). In connection with this acquisition, Calix and Ericsson also signed a non-exclusive global reseller agreement, under which Calix became Ericsson's preferred global partner for broadband access applications. Calix expected this partnership to provide Calix with an extensive new global reseller channel, and Calix believed that its acquisition of Ericsson's fiber access portfolio delivered powerful new complements to Calix's industry-leading Unified Access portfolio. Calix expected that this partnership would also provide Ericsson's existing fiber access customers with world-class support and maintenance, and an expanded portfolio of access systems and software from a leading company totally focused on access.
	The EFAA Acquisition was accounted for as a business combination under ASC Topic 805. The Company finalized the fair values of the acquired assets and assumed liabilities from Ericsson, as summarized in the following table (in thousands), and closed the measurement period in 2013.
		At November 2, 2012
	Inventory	$	9,361
	Other current asset	739
	Property and equipment	3,616
	Other current liabilities	(124		)
	Deferred tax liability	(563		)
	Net assets acquired	13,029
	Gain on bargain purchase	(1,029		)
	Total purchase price	$	12,000
	Total consideration for the purchase price was $12.0 million in cash. Because the fair value of identifiable assets acquired, net of liabilities assumed, exceeded the consideration transferred, the Company recognized a bargain purchase gain of $1.0 million, net of income taxes. The Company reassessed the recognition and measurement of identifiable assets acquired and liabilities assumed and concluded that all acquired assets and assumed liabilities were recognized and that the valuation procedures and resulting measures were appropriate. The gain is included as a separate line item on the Company's Consolidated Statements of Comprehensive Loss for the year ended December 31, 2012.
	Pursuant to the Asset Purchase Agreement, the Company received a credit of approximately $3.3 million ("Ericsson Credit") that would expire on August 31, 2013 without cash value. The Ericsson Credit was recorded at fair value as of the date of the acquisition and it could be used for consulting services, additional inventory, and test equipment agreed to by both parties. During 2013, due to the Company's marketing and selling effort as well as changes in the market, the Company succeeded in obtaining inventories and equipment from Ericsson using the Ericsson Credit in a total amount in excess of the fair value of the Ericsson Credit that was recorded by the Company upon the completion of the acquisition. The Company recorded such inventories received at their fair market value and recognized a gain of $1.7 million for the amount in excess of the fair value of the Ericsson Credit within 'Utilization of inventory credit' in our consolidated statement of comprehensive loss. Subsequent to the acquisition, Ericsson extended the expiration date of the Ericsson Credit to December 31, 2014.
	The Company recognized $1.4 million of acquisition-related costs in 2012 in connection with the EFAA Acquisition. These costs are included in the Consolidated Statements of Comprehensive Loss in the line item entitled “Acquisition-related expenses” within Operating expenses.
	The assets, liabilities, and operating results associated with the EFAA Acquisition have been included in the Company's consolidated financial statements from the date of acquisition. For 2013, it is impracticable to determine the results of operations or the revenue which resulted from the EFAA acquisition as the acquired business had been integrated into our operations in 2013. For 2012, approximately $0.6 million of our total revenue resulted from the EFAA acquisition. Pro forma results of operations have not been presented because it is impracticable to obtain the historical operating results of EFAA before the acquisition on a standalone basis and that the effect of the acquisition was not material to our consolidated results of operations.
	Acquisition of Occam Networks
	On February 22, 2011, the Company completed its acquisition of Occam Networks, Inc. ("Occam") in a stock and cash transaction valued at approximately $213.1 million which consisted of $94.5 million of cash consideration and a value of $118.6 million of common stock and equity awards issued. In connection with the consummation of the acquisition, each outstanding share of common stock of Occam was converted, effective as of February 22, 2011, into the right to receive: (i) 0.2925 shares of Calix common stock and (ii) $3.8337 in cash. In addition, (a) each outstanding Occam stock option or restricted stock unit as of immediately prior to the effective time of the acquisition which was or became vested as of the effective time of the acquisition with a per share exercise price that was less than (i) $3.8337 plus (ii) 0.2925 multiplied by the average volume weighted average trading price of Calix common stock during the five consecutive trading days ending on the trading day that was one day before the effective time of the acquisition, such amount being referred to as the cash-out consideration and (b) Occam options or restricted stock units held by persons who were not Occam employees or consultants immediately prior to the effective time of the acquisition were automatically canceled and extinguished and the vested portion thereof was automatically converted into the right to receive the cash-out consideration for the aggregate number of shares of Occam common stock that were issuable upon the exercise of such stock options or restricted stock units, less any applicable per share exercise price.
	Unvested portions of each outstanding Occam stock option or restricted stock unit held by Occam employees who continued to be employed by Calix or its subsidiaries after the effective time of the merger transaction that were not cashed out and canceled as described above were, at the effective time, automatically converted into options or restricted stock units, as the case may be, for Calix common stock, subject to adjustments in accordance with the compensatory award exchange ratio, and subject to the terms and conditions of such award prior to the effective time, including vesting and exercisability. The fair value of Calix stock options and restricted stock units issued to employees of Occam was $5.8 million including those accelerated for Occam executives associated with their severance agreements, which were executed subsequent to the acquisition date. The fair value of options was estimated using a Black-Scholes option pricing model.
	The following table represents the weighted average assumptions used to estimate fair value of stock options:
		At February 22, 2011
	Expected volatility	52%
	Expected life (years)	3.95
	Expected dividend yield	—
	Risk-free interest rate	1.65%
	The acquisition of Occam was accounted for under the acquisition method of accounting, which requires the acquired assets and assumed liabilities to be recorded based on their estimated fair values. The fair values assigned to the acquired assets and assumed liabilities are based on valuations using management's best estimates and assumptions utilizing the best information available at the time these consolidated financial statements were issued. During the measurement period (which is not to exceed one year from the acquisition date), the Company is required to retrospectively adjust the provisional assets or liabilities if new information is obtained about facts and circumstances that existed as of the acquisition date that, if known, would have resulted in the recognition of those assets or liabilities as of that date.
	The Company finalized the fair values of the acquired assets and assumed liabilities and closed the measurement period in 2011. The following table summarizes the fair value of the acquired assets and assumed liabilities related to the acquisition of Occam (in thousands):
		At February 22, 2011
	Cash and cash equivalents	$	33,631
	Restricted cash	1,054
	Accounts receivable	16,854
	Inventory	29,229
	Prepaid expenses and other assets	854
	Property and equipment	7,363
	Intangible assets:
	Trade name (useful life of 6 months)	2,290
	Customer relationships (useful life of 5 years)	51,040
	Core developed technology (useful life of 5 years)	25,494
	In-process technology	16,270
	Purchase order backlog (useful life of 10 months)	2,560
	Total intangible assets	97,654
	Goodwill	50,599
	Current liabilities	(22,414		)
	Deferred revenue	(866		)
	Long-term liabilities	(890		)
	Total	$	213,068
	Trade names represented acquired product names, which were expected to have a useful life of six months. Customer relationships represented agreements with existing Occam customers and have estimated useful lives of five years.
	Core developed technology represented technology that had reached technological feasibility and includes Occam's primary product line. The fair value of the core developed technology was determined using future discounted cash flows related to the projected income stream of the developed technology for a discrete projection period. Core developed technology is being amortized over its estimated useful life of five years.
	In-process technology represented projects that had not reached technological feasibility at the time of the acquisition and they did not have a finite useful life. See Note 3, "Goodwill and Intangible Assets" of these Notes to Consolidated Financial Statements for an update of the in-process technology acquired from Occam.
	Acquired backlog represented goods and services that the Occam customers were contractually obligated to receive in the future and was expected to have a ten month life.
	During the year ended December 31, 2011, the Company incurred $20.0 million of acquisition-related expenses that was recorded in cost of revenue, resulting from the required revaluation of inventory to its estimated fair value and an associated write-down of inventory determined as excess and obsolete. The Company also recorded $12.9 million of acquisition-related expenses within operating expenses in the twelve months ended December 31, 2011, related to severance for terminated employees and salaries for transitional employees, expenses associated with consolidating facilities, transaction costs for financial advisory, legal and accounting services, and stock-based compensation expense primarily related to accelerated vesting for certain Occam executives who terminated subsequent to the acquisition date.
	The premium paid by the Company in this transaction was attributable to the strategic benefits of creating a more competitive and efficient company, more capable of competing against larger telecommunications equipment companies in more markets and the significant cost synergies that would be obtained by the combined organization. The combined organization was expected to provide communications service providers globally with an enhanced portfolio of advanced broadband access systems, and accelerate innovation across the expanded Calix Unified Access portfolio. The acquisition was expected to result in more access options over both fiber and copper for communications service providers to deploy, which could expedite the proliferation of advanced broadband services to both residential and business subscribers, including such services as high-speed Internet, Internet protocol television, voice over internet protocol ("VOIP"), Ethernet business services, and other advanced broadband applications.
	The results of operations of Occam have been included in the Company's consolidated financial statements since the acquisition date. Pro forma results of operations are not presented because they are not significantly different from our actual consolidated results of operations for 2011 as this acquisition occurred in February 2011.

Goodwill_and_Intangible_Assets

Goodwill and Intangible Assets (Notes)	12 Months Ended
	Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'
Goodwill and Intangible Assets	'
	3. Goodwill and Intangible Assets
	Goodwill
	Goodwill was recorded as a result of the Company's acquisitions of Occam in February 2011 and Optical Solutions, Inc. ("OSI") in February 2006. This goodwill is not deductible for tax purposes, and there have been no adjustments or impairment to goodwill since the acquisition dates.
	Intangible Assets
	Intangible assets are carried at cost, less accumulated amortization. The details of intangible assets as of December 31, 2013 and December 31, 2012 are disclosed in the following table (in thousands):
			31-Dec-13							31-Dec-12
			Gross		Accumulated			Net		Gross		Accumulated			Net
			Carrying		Amortization					Carrying		Amortization
			Amount							Amount
	Core developed technology		$	68,964	$	(47,339	)	$	21,625	$	68,964	$	(38,986	)	$	29,978
	Customer relationships		54,740		(32,625		)	22,115		54,740		(22,417		)	32,323
	Total intangible assets, excluding goodwill		$	123,704	$	(79,964	)	$	43,740	$	123,704	$	(61,403	)	$	62,301
	At the end of the first quarter of 2012, upon the completion of the research and development efforts associated with the $16.3 million in-process technology that was acquired from Occam, the Company determined that this technology had a useful life of 5 years and therefore reclassified it as core developed technology. The Company began amortizing this intangible asset to cost of revenue during the second quarter of 2012.
	Amortization expense for intangible assets was $18.6 million, $17.7 million, and $18.1 million for the years ended December 31, 2013, 2012, and 2011, respectively. Expected future amortization expense for the fiscal years indicated is as follows (in thousands):
	Period	Expected Amortization Expense
	2014	$	18,561
	2015	18,561
	2016	5,805
	2017	813
	Total	$	43,740

Balance_Sheet_Details_Notes

Balance Sheet Details (Notes)	12 Months Ended
	Dec. 31, 2013
Balance Sheet Related Disclosures [Abstract]	'
Balance Sheet Details	'
	4. Balance Sheet Details
	Cash and cash equivalents consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Cash	$	62,905		$	27,157
	Money market funds	19,842			19,838
	Total cash and cash equivalents	$	82,747		$	46,995
	Accounts receivable, net consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Accounts receivable	$	44,642		$	61,680
	Allowance for doubtful accounts	(358		)	(421		)
	Product return reserve	(764		)	(1,740		)
	Accounts receivable, net	$	43,520		$	59,519
	Inventory consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Raw materials	$	6,591		$	9,377
	Finished goods	44,480			33,905
	Total inventory	$	51,071		$	43,282
	Property and equipment, net consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Test equipment	$	36,932		$	37,595
	Computer equipment and purchased software	27,280			31,582
	Furniture and fixtures	1,614			1,470
	Leasehold improvements	7,077			6,763
	Total	72,903			77,410
	Accumulated depreciation and amortization	(55,430		)	(56,327		)
	Property and equipment, net	$	17,473		$	21,083
	Depreciation and amortization expense was $10.2 million, $8.6 million, $8.0 million for the years ended December 31, 2013, 2012, and 2011, respectively.
	Accrued liabilities consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Accrued compensation and related benefits	$	13,127		$	12,906
	Accrued warranty	10,856			11,762
	Accrued professional and consulting fees	1,634			1,740
	Accrued excess and obsolete inventory at contract manufacturers	756			1,357
	Accrued customer rebates	712			1,565
	Accrued business travel expenses	540			593
	Sales and use tax payable	521			929
	Income taxes payable	368			627
	Accrued other	3,561			4,697
	Total accrued liabilities	$	32,075		$	36,176
	Deferred cost of revenue consisted entirely of products and services. Deferred revenue consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Deferred Revenue:
	Product and services - current	$	32,051		$	36,715
	Extended warranty - current	2,811			2,600
	Extended warranty - non-current	18,335			15,711
	Product and services - non-current	96			71
	Total deferred revenue	$	53,293		$	55,097
	The following table provides the balances and changes in the components of accumulated other comprehensive income (loss) for the years indicated (in thousands):
		Foreign Currency Translation Adjustments			Unrealized Gain (Loss) on Investments			Accumulated Other Comprehensive Income
	Balance at 12/31/2010	$	10		$	21		$	31
	Current period other comprehensive income (loss)	88			(21		)	67
	Balance at 12/31/2011	98			—			98
	Current period other comprehensive income	34			—			34
	Balance at 12/31/2012	132			—			132
	Current period other comprehensive income	58			—			58
	Balance at 12/31/2013	$	190		$	—		$	190

Commitments_and_Contingencies_

Commitments and Contingencies (Notes)	12 Months Ended
	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	5. Commitments and Contingencies
	Lease Commitments
	The Company leases office space under non-cancelable operating leases. Certain of the Company’s operating leases contain renewal options and rent acceleration clauses. Future minimum payments under the non-cancelable operating leases consisted of the following as of December 31, 2013 (in thousands):
	Period	Minimum Future Lease Payments
	2014	$	3,438
	2015	2,743
	2016	2,252
	2017	2,177
	2018	1,894
	Thereafter	252
	Total	$	12,756
	The above total minimum payments have not been reduced by minimum sublease rentals of $0.2 million due in the future under non-cancelable sublease of a portion of the Company's office in Fremont, California.
	The Company leases its primary office space in Petaluma, California under a lease agreement ("Petaluma Lease") that extends through February 2014. On January 28, 2013, the Company entered into an amendment to its Petaluma Lease ("Amendment") to extend the lease term to February 2019. In connection with the Petaluma Lease and the Amendment, the Company received lease incentives of $1.2 million and $0.4 million, respectively, which can be used for leasehold improvements or be applied as credits to rent payments. The Company had capitalized the full amount of the lease incentives upon inception of the respective agreement and these incentives are being amortized to reduce rent expense over the extended lease term. As of December 31, 2013, total unamortized lease incentive was $0.5 million, of which $0.1 million and $0.4 million were included in "Accrued liabilities" and "Other long-term liabilities", respectively, in the Consolidated Balance Sheet as of December 31, 2013. Payments under the Company’s operating leases that escalate over the term of the lease are recognized as rent expense on a straight-line basis.
	The above table also includes future minimum lease payments primarily for our facilities in Minneapolis, Minnesota; Acton, Massachusetts; Nanjing, China; Richardson, Texas; and Fremont, San Jose, and Santa Barbara, California, which expire at various dates through 2019, and for certain office equipment under non-cancelable operating lease agreements, which expire at various dates through 2015.
	For the years ended December 31, 2013, 2012 and 2011, total rent expense of the Company, net of sublease income, was $3.9 million, $3.5 million, $3.6 million, respectively.
	Purchase Commitments
	The Company’s primary contract manufacturers place orders for component inventory in advance based upon the Company’s build forecasts in order to reduce manufacturing lead times and ensure adequate component supply. The components are used by the contract manufacturers to build the products included in the build forecasts. The Company does not take ownership of the components and any outstanding orders do not represent firm purchase commitments pursuant to the Company’s agreement with the contract manufacturer. The Company will provide purchase orders to its contract manufacturers in order to fulfill its monthly finished product inventory requirements. The Company incurs a liability when the manufacturer has converted the component inventory to a finished product and takes ownership of the inventory when transferred to the designated shipping warehouse. However, historically, the Company has reimbursed its primary contract manufacturer for component inventory purchases when this inventory has been rendered excess or obsolete, for example due to manufacturing and engineering change orders resulting from design changes, manufacturing discontinuation of parts by its suppliers, or in cases where inventory levels greatly exceed projected demand. The estimated excess and obsolete inventory liabilities related to such manufacturing and engineering change orders, which are included in accrued liabilities in the accompanying balance sheets, were $0.8 million and $1.4 million as of December 31, 2013 and 2012, respectively. The Company records these amounts in cost of products and services in its Consolidated Statements of Comprehensive Loss.
	As of December 31, 2013, the Company had non-cancelable outstanding purchase orders of $16.3 million for finished goods to be delivered by its contract manufacturers within one year.
	Accrued Warranty
	The Company provides a warranty for its hardware products. Hardware generally has a one to five-year warranty from the date of shipment. The Company accrues for potential warranty claims based on the Company’s historical claims experience. The adequacy of the accrual is reviewed on a periodic basis and adjusted, if necessary, based on additional information as it becomes available.
	Changes in the Company’s warranty reserve in the periods as indicated were as follows (in thousands):
		Years Ended December 31,
		2013			2012			2011
	Balance at beginning of period	$	11,762		$	12,104		$	3,789
	Accrued warranty from the Occam acquisition	—			—			8,500
	Warranty charged to cost of revenue	4,350			4,701			5,883
	Utilization of warranty	(5,256		)	(5,043		)	(6,068		)
	Balance at end of period	$	10,856		$	11,762		$	12,104
	Litigation
	From time to time, the Company is involved in various legal proceedings arising from the normal course of business activities.
	On September 16, 2010, the Company, two direct, wholly-owned subsidiaries of the Company, and Occam entered into an Agreement and Plan of Merger and Reorganization (the “Merger Agreement”). In response to the announcement of the Merger Agreement on October 6, 2010, a purported class action complaint was filed by stockholders of Occam in the Delaware Court of Chancery: Steinhardt v. Howard-Anderson, et al. (Case No. 5878-VCL). On November 24, 2010, these stockholders filed an amended complaint (the “amended Steinhardt complaint”). The amended Steinhardt complaint named Occam (which has since been merged into Calix) and the members of the Occam board of directors as defendants. The amended Steinhardt complaint did not name Calix as a defendant.
	The amended Steinhardt complaint sought injunctive relief rescinding the merger transaction and an award of damages in an unspecified amount, as well as plaintiffs' costs, attorney's fees, and other relief.
	The merger transaction was completed on February 22, 2011. On January 6, 2012, the Delaware court ruled on a motion for sanctions brought by the defendants against certain of the lead plaintiffs. The Delaware court found that lead plaintiffs Michael Steinhardt, Steinhardt Overseas Management, L.P., and Ilex Partners, L.L.C., collectively the “Steinhardt Plaintiffs,” had engaged in improper trading of Calix shares, and dismissed the Steinhardt Plaintiffs from the case with prejudice. The court further held that the Steinhardt Plaintiffs are: (i) barred from receiving any recovery from the litigation, (ii) required to self-report to the SEC, (iii) directed to disclose their improper trading in any future application to serve as lead plaintiff, and (iv) ordered to disgorge trading profits of $0.5 million,to be distributed to the remaining members of the class of former Occam stockholders. The Delaware court also granted the motion of the remaining lead plaintiffs, Herbert Chen and Derek Sheeler, for class certification, and certified Messrs. Chen and Sheeler as class representatives. The certified class is a non-opt-out class consisting of all owners of Occam common stock whose shares were converted to shares of Calix on the date of the merger transaction, with the exception of the defendants in the Delaware action and their affiliates. Chen and Sheeler, on behalf of the class of similarly situated former Occam stockholders, continue to seek an award of damages in an unspecified amount.
	Fact discovery in the case closed on April 30, 2013. On June 11, 2013, the plaintiffs filed their Second Amended Class Action Complaint for Breach of Fiduciary Duty (“Second Amended Complaint”). The Second Amended Complaint adds Occam's former CFO as a defendant, and alleges that each of the defendants breached their fiduciary duties by failing to attempt to obtain the best purchase price for Occam and failing to disclose certain allegedly material facts about the merger transaction in the preliminary proxy statement and prospectus included in the Registration Statement on Form S-4 filed with the SEC on November 2, 2010.
	On July 17, 2013, attorneys representing all of the defendants named in the Second Amended Complaint filed Defendants' Opening Brief in Support of Their Motion for Summary Judgment, arguing that all defendants are entitled to summary judgment on all counts of the Second Amended Complaint. Plaintiffs' answering brief to the motion for summary judgment was filed on September 3, 2013, and defendants' reply brief was filed on October 4, 2013. A hearing on the motion for summary judgment was held on December 6, 2013. A decision on that motion is pending. If that decision does not dispose of the case entirely, the case is likely to go to trial at some time in 2014.
	The Company believes that the allegations in the Second Amended Complaint are without merit and intends to continue to vigorously contest the action. However, there can be no assurance that the Company will be successful in defending this ongoing action. In addition, the Company has obligations, under certain circumstances, to hold harmless and indemnify each of the former Occam directors and officers against judgments, fines, settlements and expenses related to claims against such directors and otherwise to the fullest extent permitted under Delaware law and Occam's bylaws and certificate of incorporation. Such obligations may apply to this lawsuit.
	The Company is not currently a party to any other legal proceedings that, if determined adversely to the Company, would individually or in the aggregate have a material adverse effect on the Company's business, operating results or financial condition.
	Guarantees
	The Company from time to time enters into certain types of contracts that contingently require it to indemnify various parties against claims from third parties. These contracts primarily relate to (i) certain real estate leases, under which the Company may be required to indemnify property owners for environmental and other liabilities, and other claims arising from the Company’s use of the applicable premises, (ii) certain agreements with the Company’s officers, directors, and employees, under which the Company may be required to indemnify such persons for liabilities arising out of their relationship with the Company, (iii) contracts under which the Company may be required to indemnify customers against third-party claims that a Company product infringes a patent, copyright, or other intellectual property right and (iv) procurement or license agreements, under which the Company may be required to indemnify licensors or vendors for certain claims that may be brought against them arising from the Company’s acts or omissions with respect to the supplied products or technology.
	Generally, a maximum obligation under these contracts is not explicitly stated. Because the obligated amounts associated with these types of agreements are not explicitly stated, the overall maximum amount of the obligation cannot be reasonably estimated. Historically, the Company has not been required to make payments under these obligations, and no liabilities have been recorded for these obligations in the Company’s balance sheets.

Fair_Value_Measurements_Notes

Fair Value Measurements (Notes)	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Fair Value Measurements	'
	6. Fair Value Measurements
	In accordance with ASC Topic 820, "Fair Value Measurements and Disclosures," (“ASC Topic 820”), the Company measures its cash equivalents and marketable securities at fair value on a recurring basis. ASC Topic 820 clarifies that fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, ASC Topic 820 establishes a three-tier value hierarchy, which prioritizes the inputs used in measuring fair value as follows:
	Level 1 – Observable inputs that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets.
	Level 2 – Observable inputs other than quoted prices included in Level 1 for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-driven valuations in which all significant inputs and significant value drivers are observable in active markets.
	Level 3 – Unobservable inputs to the valuation derived from fair valuation techniques in which one or more significant inputs or significant value drivers are unobservable. The fair value hierarchy also requires the Company to maximize the use of observable inputs, when available, and to minimize the use of unobservable inputs when determining inputs and determining fair value.
	The following table sets forth the Company's financial assets measured at fair value as of December 31, 2013 and December 31, 2012, based on the three-tier fair value hierarchy (in thousands):
	As of December 31, 2013	Level 1		Total
	Money market funds	$	19,842	$	19,842
	Total	$	19,842	$	19,842
	As of December 31, 2012	Level 1		Total
	Money market funds	$	19,838	$	19,838
	Total	$	19,838	$	19,838
	The Company's money market funds consisted of highly liquid investments with original maturities of three months or less and are classified as cash equivalents. The carrying amounts of our money market funds approximate their fair values due to their nature, duration and short maturities. The fair values of money market funds were derived from quoted market prices as active markets for these instruments exist. The Company has no level 2 or level 3 financial assets.

Net_Loss_per_Share_Notes

Net Loss per Share (Notes)	12 Months Ended
	Dec. 31, 2013
Earnings Per Share [Abstract]	'
Net Loss per Share	'
	7. Net Loss per Share
	The following table sets forth the computation of basic and diluted net loss per share for the periods indicated (in thousands, except per share data):
		Years Ended December 31,
		2013			2012			2011
	Numerator:
	Net loss	$	(17,265	)	$	(28,326	)	$	(52,550	)
	Denominator:
	Weighted-average common shares outstanding	49,419			48,180			45,546
	Basic and diluted net loss per common share	$	(0.35	)	$	(0.59	)	$	(1.15	)
	Potentially dilutive shares, weighted-average	5,308			4,454			3,695
	For all the three years presented, unvested restricted stock awards are included in the calculation of basic weighted-average shares because such shares are participating securities, however the impact was immaterial.
	Potentially dilutive shares are excluded from the computation of the basic and diluted net loss per share because their effect is antidilutive. These antidilutive shares were primarily from stock options, restricted stock units and performance restricted stock awards.

Stockholders_Equity_Notes

Stockholders' Equity (Notes)	12 Months Ended
	Dec. 31, 2013
Stockholders' Equity Note [Abstract]	'
Stockholders' Equity	'
	8. Stockholders’ Equity
	Common Stock
	On March 2, 2010, the Company’s board of directors approved an amended and restated certificate of incorporation that increased the authorized common stock to 100 million shares and the authorized preferred stock to 5.0 million shares effective immediately prior to the completion of the Company’s initial public offering on March 26, 2010.
	On March 21, 2010, the Company’s board of directors approved an amended and restated certificate of incorporation effecting a 2-for-3 reverse stock split of its common stock and all convertible preferred stock. The par value and the authorized shares of the common stock and convertible preferred stock were not adjusted as a result of the reverse stock split. All issued and outstanding common stock, convertible preferred stock, warrants for common stock, warrants for preferred stock, and per share amounts contained in the financial statements have been retroactively adjusted to reflect this reverse stock split for all periods presented. The reverse stock split was effected on March 23, 2010.
	On March 26, 2010, the Company completed its initial public offering in which 4,166,666 shares of common stock were sold by the Company at a public offering price of $13.00 per share. Gross proceeds of $54.2 million from the sale of common stock by the Company were reduced by issuance costs of $4.6 million and underwriters fees of $3.8 million. On April 8, 2010, the Company issued and sold 949,339 shares of common stock resulting from the exercise of the underwriters’ option to purchase common shares associated with the Company’s initial public offering. This sale resulted in gross proceeds of $12.3 million based on an initial public offering price of $13.00 per share of common stock, which were reduced by underwriters’ discount and offering expenses payable by the Company of $0.8 million.
	On February 22, 2011, in connection with the acquisition of Occam, the Company issued 6.4 million shares of the Company’s common stock, a value of $117.2 million. For more information regarding the acquisition of Occam see Note 2, “Business Combinations” of these Notes to Consolidated Financial Statements.
	Holders of our common stock are entitled to receive dividends, if any, as may be declared from time to time by our board of directors out of legally available funds. No dividends have been declared or paid as of December 31, 2013. In the event of our liquidation, dissolution or winding up, holders of our common stock will be entitled to share ratably in the net assets legally available for distribution to stockholders after the payment of all of our debts and other liabilities and the satisfaction of any liquidation preference granted to the holders of any then outstanding shares of preferred stock.
	Preferred Stock
	The board of directors has the authority, without action by stockholders with the exception of stockholders who hold board positions, to designate and issue up to 5.0 million shares of preferred stock in one or more series and to fix the rights, preferences, privileges and restrictions thereof. These rights, preferences and privileges could include dividend rights, conversion rights, voting rights, terms of redemption, liquidation preferences, sinking fund terms and the number of shares constituting any series or the designation of such series, any or all of which may be greater than the rights of common stock. The issuance of the Company’s preferred stock could adversely affect the voting power of holders of common stock and the likelihood that such holders will receive dividend payments and payments upon liquidation. In addition, the issuance of preferred stock could have the effect of delaying, deferring or preventing a change in control of the Company or other corporate action. Subsequent to the Company’s initial public offering and the conversion of all preferred stock outstanding at that date, the board of directors has not designated any rights, preference or powers of any preferred stock and no shares of preferred stock have been issued.
	Equity Incentive Plans
	Prior to March 2010, the Company had the 2000 Stock Plan ("2000 Plan") and the Amended and Restated 2002 Stock Plan ("2002 Plan") (together, "Prior Plans"). Under the Prior Plans, the Company may grant incentive stock options at a price not less than 100% of the fair market value of the common stock on the date of grant and non-statutory stock options at a price not less than 85%, or, with respect to the 2002 Plan, 100% of the fair market value of the common stock on the date of grant. Before April 2004, certain options could be granted with the right to exercise those options before vesting. The majority of the stock options granted under the Prior Plans vest over 4 years and expire in 10 years.
	On March 2, 2010, the Company’s Board of Directors approved the 2010 Equity Incentive Award Plan ("2010 Plan") which allows the Company to grant stock options, restricted stock awards ("RSA"), restricted stock units ("RSU"), performance restricted stock units ("PRSU"), stock appreciation rights, dividend equivalents, deferred stock, and stock payments to employees, directors and consultants of the Company. A total of 4,666,666 shares of common stock were reserved for future issuance under the 2010 Plan, which became effective upon the completion of the Company’s initial public offering of common stock. In addition, on the first day of each year beginning in 2011 and ending in 2020, the 2010 Plan provides for an annual automatic increase to the shares reserved for issuance and no more than 17,150,494 shares of Common Stock may be issued upon the exercise of Incentive Stock Options. Pursuant to the automatic annual increase, total 1,999,998 additional shares had been reserved under the 2010 Plan since 2011.
	Upon the effectiveness of the 2010 Plan, equity awards were granted only under the 2010 Plan and shares of common stock previously reserved for issuance under the Prior Plans became available for issuance under the 2010 Plan. To date, awards granted under the 2010 Plan consist of stock options, RSAs, RSUs and PRSUs.
	Stock options granted under the 2010 Plan are granted in general at a price not less than 100% of the fair market value of the common stock on the date of grant. Generally, the options issued under the 2010 Plan vest 25% on the first anniversary of the vesting commencement date and on a monthly basis thereafter for a period of an additional three years. The options have a maximum term of ten years.
	Each RSU granted under the 2010 Plan represents a right to receive one share of the Company’s common stock (subject to adjustment for certain specified changes in the capital structure of the Company) upon the completion of a specific period of continued service. The majority of RSUs granted vest over four years.
	In July 2011, the Company granted 423,000 RSAs to executives under the 2010 Plan, which vest 25% per year for 4 years from the grant date. Upon issuance of RSA, the holder is entitled to have all the rights of a stockholder, subject to the restrictions in his or her Award Agreement, including the right to receive all dividends and other distributions paid or made with respect to the shares.
	In 2012, the Company commenced granting PRSUs to its executives with two-year and three-year performance periods. The performance criterion is based on the relative total shareholder return (“TSR”) of Calix common stock as compared to the TSR of the Company’s peer group. The TSR is calculated by dividing (a) the average closing trading price for the 90-day period ending on the last day of the applicable performance period by (b) the average closing trading price for the 90-day period immediately preceding the first day of the applicable performance period. This TSR is then used to derive the achievement ratio, which is then multiplied by the number of units in the grant to derive the common stock to be issued for each performance period, which may equal from zero percent (0%) to two hundred percent (200%) of the target award.
	Stock Option Exchange Program
	On September 23, 2009, the Company completed a stock option exchange program, which was approved by its board of directors, pursuant to which eligible employees were able to exchange eligible stock options for restricted stock units on a one-for-one basis. Pursuant to the exchange, the Company canceled options for 3.4 million shares of the Company’s common stock and issued an equivalent number of RSUs to eligible holders on September 23, 2009, of which 50% vested in October 2010 and the remaining 50% vested in May 2011. In connection with the RSU grants, the unrecognized compensation expense related to the exchanged options was expensed over the remainder of the original vesting period of the options exchanged. The incremental cost due to the exchange was deferred until a liquidity event, which happened with the Company’s IPO, and had been recognized in accordance with the vesting periods described above.
	Stock Options
	The following table summarizes the activity of stock options under the Company’s equity incentive plans (in thousands, except per share data):
						Weighted-				Weighted-Average
						Average				Remaining		Aggregate
			Number of			Exercise Price				Contractual Life		Intrinsic
	Stock Options		Shares			Per Share				(in years)		Value (1)
	Outstanding as of December 31, 2012		2,213			$	13.51
	Granted		573			8.57
	Exercised		(160	)		4.66
	Forfeited or expired		(66	)		13.32
	Outstanding as of December 31, 2013		2,560			$	12.96			7.6		$	2,474
	Vested and expected to vest at December 31, 2013		2,520			$	13.02			7.6		$	2,414
	(1) Amounts represent the difference between the exercise price and the fair market value of common stock at December 31, 2013 for all in the money options outstanding.
	During the years ended December 31, 2013, 2012, and 2011, total intrinsic value of stock options exercised was $1.0 million, $0.6 million, $2.7 million, respectively. Total cash received from employees as a result of stock option exercises in 2013, 2012, and 2011 was $0.7 million, $0.2 million, $0.8 million, respectively.
	The following table summarizes information about stock options outstanding and exercisable at December 31, 2013 (in thousands, except year and per share data):
									Options Outstanding									Options Exercisable
												Weighted-Average		Weighted-							Weighted-
									Number			Remaining		Average				Number			Average
									of Shares			Contractual Life		Exercise Price				of Shares			Exercise Price
	Range of Exercise Prices								Outstanding			(in years)		Per Share				Exercisable			Per Share
	$	1.2		—	$	6.8			453			7.3		$	6.31			255			$	6.12
	6.95			—	8.38				183			8.2		7.67				61			7.47
	8.41			—	8.41				467			9.1		8.41				95			8.41
	8.55			—	10.71				436			8		10.45				216			10.35
	10.85			—	18.86				508			7.2		15.58				351			15.74
	19.4			—	4,401.93				513			6.4		24.42				387			25.4
	$	1.2		—	$	4,401.93			2,560			7.6		$	12.96			1,365			$	14.94
	Restricted Stock Units, Performance Restricted Stock Units, and Restricted Stock Awards
	The following table summarizes the activities of the Company's RSUs, PRSUs, and RSAs under the Company’s equity incentive plans (in thousands, except per share data):
		RSUs							PRSUs							RSAs
					Weighted-Average							Weighted-Average							Weighted-Average
					Grant Date							Grant Date							Grant Date
		Number of			Fair Value				Number of			Fair Value				Number of			Fair Value
		Shares			Per Share				Shares			Per Share				Shares			Per Share
	Outstanding at December 31, 2012	1,762			$	11.67			183			$	14.78			299			$	21.67
	Granted	705			9.2				230			11.24				—			—
	Vested	(822	)		11.07				—			—				(95	)		21.67
	Canceled	(139	)		9.51				—			—				(15	)		21.67
	Outstanding at December 31, 2013	1,506			$	11.04			413			$	12.81			189			$	21.67
	Upon vesting of certain RSUs and RSAs, the Company withheld shares with value equivalent to the employees’ minimum statutory obligation for the applicable income and other employment taxes, and remitted the cash to the appropriate taxing authorities. The number of shares withheld was based on the value of the RSUs or RSAs on their vesting date as determined by the Company’s closing stock price. The withheld shares are reserved for future grant and issuance under the 2010 Plan.
	Modification of Stock Awards
	In February 2013, the Company entered into a Transition and Separation Agreement ("Agreement") with Roger Weingarth, the Company's former Executive Vice President and Chief Operating Officer. Under the Agreement, Mr. Weingarth transitioned to the role of advisor to the Chief Executive Officer of the Company effective as of April 1, 2013, and would terminate his employment with the Company on March 31, 2014 ("Termination Date"). Upon his termination, the Agreement provides for, among other things, the acceleration of the vesting of his unvested stock options, RSAs and RSUs held by him as of the Termination Date. In accordance with ASC Topic 718, total fair value of the accelerated stock awards after the modification is $0.6 million, which is being recognized on a straight-line basis over the remaining service period through the Termination Date. During the year ended December 31, 2013, $0.5 million of the total fair value has been recognized in general and administrative expenses of the Consolidated Statement of Comprehensive Loss in this Form 10-K.
	Employee Stock Purchase Plan
	The Company’s 2010 Employee Stock Purchase Plan, as amended (“2010 ESPP”) allows employees to purchase shares of the Company’s common stock through payroll deductions of up to 15 percent of their annual compensation subject to certain Internal Revenue Code limitations. In addition, no participant may purchase more than 2,000 shares of common stock in each offering period.
The offering periods under the 2010 ESPP are six-month periods commencing on June 1 and December 1 of each year. The price of common stock purchased under the plan is 85 percent of the lower of the fair market value of the common stock on the commencement date and exercise date of each six-month offering period.
The 2010 ESPP, as amended in 2012, provides for the issuance of a maximum of 4.3 million shares of common stock. During the twelve months ended December 31, 2013, 685,781 shares were purchased and issued. As of December 31, 2013, there were 2.6 million shares available for issuance.
Stock Based Compensation
In accordance with ASC Topic 718, stock-based compensation expense associated with stock options, RSUs, PRSUs, RSAs, and purchase rights under the 2010 ESPP is measured at the grant date based on the fair value of the award, and is recognized, net of forfeitures, as expense over the remaining requisite service period on a straight-line basis. During the years ended December 31, 2013, 2012, and 2011, the Company recorded stock-based compensation expense of $19.9 million, $17.4 million and $21.6 million, respectively.
The following table summarizes the weighted-average grant date fair values of the Company's stock-based awards granted in the periods indicated:
	Years Ended December 31,
	2013				2012				2011
Stock options	$	4.89			$	4.68			$	9.77
RSUs	$	9.2			$	6.55			$	21.33
PRSUs	$	11.24			$	14.81			N/A
RSAs	N/A				N/A				$	21.67
ESPP	$	2.94			$	2.34			$	3.48
The Company values the RSUs and RSAs at the closing market price of the Company’s common stock on the date of grant.
The fair value of the PRSU with a market condition is estimated on the date of award, using a Monte Carlo simulation model to estimate the TSR of the Company's stock in relation to the peer group over each performance period. Compensation cost on PRSUs with a market condition is not adjusted for subsequent changes in the Company's stock performance or the level of ultimate vesting.
The Company estimates the fair value of stock options and purchase rights under the 2010 ESPP at the grant date using the Black-Scholes option-pricing model. This model requires the use of the following assumptions:
(i) Expected volatility of the Company's common stock - Starting in the fourth quarter of 2012, the Company computed its expected volatility assumption based on a blended volatility (50% historical volatility and 50% implied volatility from traded options on the Company's common stock). This change of the method was made as the Company's common stock has now been publicly traded for more than two years, a sufficient history of stock prices had been developed. The selection of a blended volatility assumption was based upon the Company's assessment that a blended volatility is more representative of the Company's future stock price trend as it weighs the historical volatility with the future implied volatility. Expected volatilities computed using this new method for stock options granted in the fourth quarter of 2012 was 66%. Prior to the fourth quarter of 2012, the Company’s computation of expected volatility was based on the Company’s peer group in the industry in which the Company does business. Expected volatilities computed using the old method for stock options granted in the first three quarters of 2012 ranged from 55% to 56%.
(ii) Expected life of the option award - Represents the weighted-average period that the stock options are expected to remain outstanding. The Company’s computation of expected life utilizes the simplified method in accordance with Staff Accounting Bulletin No. 110 ("SAB 110") due to the lack of sufficient historical exercise data to provide a reasonable basis upon which to estimate expected term. The mid-point between the vesting date and the expiration date is used as the expected term under this method.
(iii) Expected dividend yield - Assumption is based on the Company's history of not paying dividends and no future expectations of dividend payouts.
(iv) Risk-free interest rate - Based on the U.S. Treasury yield curve in effect at the time of grant with maturities approximating the grant’s expected life.
The following table summarizes the weighted-average assumptions used in estimating the grant-date fair value of stock options and of each employee’s purchase right under the 2010 ESPP in the periods indicated:
	Years Ended December 31,
Stock Options	2013			2012			2011
Expected volatility	62	%		56	%		52	%
Expected life (years)	6.05			6.25			6.25
Expected dividend yield	—			—			—
Risk-free interest rate	1.14	%		1.06	%		2.11	%
	Years Ended December 31,
ESPP	2013			2012			2011
Expected volatility	50	%		63	%		52	%
Expected life (years)	0.5			0.5			0.5
Expected dividend yield	—			—			—
Risk-free interest rate	0.09	%		0.13	%		0.66	%
In addition, the Company applies an estimated forfeiture rate to awards granted and records stock-based compensation expense only for those awards that are expected to vest. Forfeiture rates are estimated at the time of grant based on the Company's historical experience. Further, to the extent the Company's actual forfeiture rate is different from management's estimate, stock-based compensation is adjusted accordingly.
On February 22, 2011, in connection with the acquisition of Occam (see Note 2, "Business Combinations" of these Notes to Consolidated Financial Statements), the Company issued 536,190 stock options and 42,654 RSUs to certain Occam employees. The grants were in exchange for certain options and RSUs that were held by Occam employees prior to the acquisition which retained the original vesting schedule of the initial Occam grants, except for certain equity awards held by Occam executives that were accelerated in association with their severance agreements. The Company estimated the fair value of $5.8 million of the options and RSUs in accordance with ASC Topic 718. In accordance with ASC Topic 805, the Company allocated the value of $1.4 million of certain options and RSUs to consideration in the business combination with the remaining value of $4.5 million allocated to post-combination expense to be recognized over the remaining service period of the grants.
As of December 31, 2013, unrecognized stock-based compensation expenses by award type, net of estimated forfeitures, and their expected weighted-average recognition periods are summarized in the following table (in thousands).
		As of December 31, 2013
		Stock Option				RSU				PRSU				RSA				ESPP
Unrecognized stock-based compensation expense		$	6,391			$	10,861			$	1,801			$	2,392			$	662
Weighted-average amortization period (in years)		2.2				2.3				1.3				1.5				0.4
Common Stock Warrants
Warrants to purchase convertible preferred stock that did not expire at the close of the Company’s initial public offering, in March 2010, converted to warrants to purchase common stock at the applicable conversion rate for the related preferred stock. As of December 31, 2013, the following warrants to purchase common stock were outstanding (in thousands, except per share data):
Expiration Date		Exercise Price				Number of Warrants Outstanding
		Per Share
August 16, 2014		$	10.26			8
September 4, 2017		$	19.56			15
						23
Shares Reserved for Future Issuance
The Company had common shares reserved for future issuance as follows (in thousands):
	As of December 31,
	2013			2012			2011
Stock options outstanding	2,560			2,213			1,661
Restricted stock units outstanding	1,506			1,762			1,775
Performance restricted stock units outstanding	413			183			—
Shares available for future grant under 2010 Plan	3,652			3,959			4,508
Shares available for future issuance under ESPP	2,574			3,260			579
Common stock warrants	23			23			23
Total	10,728			11,400			8,546

Employee_Benefit_Plan

Employee Benefit Plan	12 Months Ended
	Dec. 31, 2013
Compensation and Retirement Disclosure [Abstract]	'
Employee Benefit Plan	'
	9. Employee Benefit Plan
	The Company sponsors a 401(k) tax-deferred savings plan for all employees who meet certain eligibility requirements. Participants may contribute, on a pre-tax basis, a percentage of their annual compensation, but not to exceed a maximum contribution amount pursuant to Section 401(k) of the Internal Revenue Code. The Company, at the discretion of the board of directors, may make additional matching contributions on behalf of the participants. The Company made matching contributions totaling $1.5 million, $1.4 million, and $1.3 million in 2013, 2012 and 2011, respectively.

Credit_Facility_Notes

Credit Facility (Notes)	12 Months Ended
	Dec. 31, 2013
Line of Credit Facility [Abstract]	'
Credit Facility	'
	10. Credit Facility
	The Company had a revolving credit facility ("Prior Credit Facility") of $30.0 million with Silicon Valley Bank based upon a percentage of eligible accounts receivable, which matured on June 30, 2013. After the Prior Credit Facility matured on June 30, 2013, the Company cash collateralized the outstanding letters of credit with Silicon Valley Bank. As of December 31, 2013, the Company had $0.3 million cash restricted for collateralizing the outstanding letters of credit with Silicon Valley Bank.
	On July 29, 2013, the Company entered into a credit agreement with Bank of America, N.A. The credit agreement is structured such that other financial institutions can at a later time become party to the credit agreement through an amendment via a syndication process (collectively, together with Bank of America, N.A., the "Lenders"). The credit agreement provides for a revolving facility in the aggregate principal amount of up to $50.0 million, which includes a $20.0 million sublimit for the issuance of letters of credit and a $10.0 million sublimit for a swingline facility. Subject to customary conditions, up to $25.0 million of the revolving facility may be converted to a term loan facility at any time prior to the maturity of the revolving facility. The revolving facility matures on July 29, 2016, but may be extended up to two times (each extension for an additional one-year period) upon mutual agreement of the Company and the Lenders. The credit facility is secured by substantially all of the Company's assets, including its intellectual property. Proceeds of the credit facility may be used for general corporate purposes and permitted acquisitions.
	Loans under the credit facility bear interest at an annual rate equal to the base rate plus 0.75% to 1.25% or LIBOR plus 2.00% to 2.50% based on a leverage ratio of consolidated funded indebtedness to consolidated Adjusted EBITDA (customarily defined). Interest on the revolving facility is due quarterly, and any outstanding interest and principal is due on the maturity date of the revolving facility. The Company is required to repay principal on a term loan in twenty equal quarterly payments from the date the Company enters into a term loan, and all outstanding principal and accrued interest is due on the revolving facility maturity date. Swingline loans must be repaid on the earlier of (i) ten business days after a loan is made and (ii) the revolving facility maturity date. The Company is also required to pay commitment fees of 0.25% per year on any unused portions of this facility.
	The credit facility includes affirmative and negative covenants applicable to the Company that are typical for credit facilities of this type. Furthermore, the credit agreement requires us to maintain certain financial covenants, including a maximum consolidated leverage ratio, and a minimum consolidated liquidity ratio of cash, cash equivalents and accounts receivable to consolidated funded indebtedness. As of December 31, 2013, the Company was in compliance with these requirements. The credit facility also includes customary events of default, the occurrence and continuation of which would provide the Lenders with the right to demand immediate repayment of any principal and unpaid interest under the credit facility, and to exercise remedies against us and the collateral securing the loans under the credit facility.
	As of December 31, 2013, there was $50.0 million available for borrowing under this credit facility.
	The Company incurred $0.3 million of debt issuance costs that were directly attributable to the issuance of this credit facility. These costs will be amortized over three years starting from the effective date of the credit facility. As of December 31, 2013, the unamortized debt issuance costs of $0.3 million were included within "Other assets" in the Company's Consolidated Balance Sheets.

Income_Taxes_Notes

Income Taxes (Notes)	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	11. Income Taxes
	The Company recorded a provision for/(benefit from) income taxes of $(14) thousand, $0.2 million, and $0.2 million, in 2013, 2012 and 2011, respectively. The income tax benefit for 2013 primarily consisted of state alternative minimum tax (AMT) and state and foreign income taxes, net of the tax benefit recorded from the utilization of a portion of the AMT net operation loss (NOL) acquired from Occam. The remainder of the AMT NOL, which was approximately $5.3 million as of December 31, 2013, will be carried forward by the Company to offset future AMT income.
	Provision for (benefit from) income taxes consisted of the following for the periods indicated (in thousands):
		Years Ended December 31,
		2013				2012				2011
	Federal current income tax (benefit)	$	(274	)		$	152			$	—
	State current income tax	41				73				114
	Foreign current income tax	315				440				228
	Federal deferred income tax (benefit)	—				(474		)		—
	State deferred income tax (benefit)	—				(89		)		—
	Foreign deferred income tax (benefit)	(96		)		56				(118		)
	Provision for (benefit from) income taxes	$	(14	)		$	158			$	224
	The differences between the statutory tax rate and the effective tax rate, expressed as a percentage of loss before income taxes, were as follows:
		Years Ended December 31,
		2013			2012			2011
	Federal statutory rate	34	%		34	%		34	%
	State statutory rate	3.4	%		5.2	%		5.2	%
	Foreign operations	1.4	%		0.1	%		0.2	%
	Release of FIN 48 liability and interest	0.7	%		—	%		—	%
	R&D tax credits	13.1	%		2.5	%		2.1	%
	Release of valuation allowance related to EFAA acquisition	—	%		2	%		—	%
	Acquisition-related costs	—	%		1.2	%		(1.5	)%
	Other permanent items	(4.5	)%		0.1	%		(1.6	)%
	2012 tax true-up	1	%		—	%		—	%
	Valuation allowance	(49.0	)%		(45.7	)%		(38.8	)%
	Effective tax rate	0.1	%		(0.6	)%		(0.4	)%
	The significant components of the Company’s deferred tax assets and liabilities were as follows (in thousands):
		As of December 31,
		2013				2012
	Deferred tax assets:
	Net operating loss carryforwards	$	168,431			$	180,005
	Tax credit carryforwards	22,507				20,154
	Depreciation and amortization	2,996				2,858
	Accruals and reserves	11,479				11,353
	Deferred revenue	12,037				13,367
	Stock-based compensation	5,570				3,592
	Other	450				294
	Gross deferred tax assets	223,470				231,623
	Valuation allowance	(207,315		)		(207,441		)
	Net deferred tax assets	16,155				24,182
	Deferred tax liabilities:
	Intangible assets	(15,988		)		(24,120		)
	Net deferred tax assets reflected in balance sheet	$	167			$	62
	Management reviews the recognition of deferred tax assets to determine if realization of such assets is more likely than not. The realization of the Company’s deferred tax assets is dependent upon future earnings. The Company has been in a cumulative loss position since inception, which represents a significant piece of negative evidence. Using the more likely than not criteria specified in the applicable accounting guidance, this negative evidence cannot be overcome by positive evidence currently available to the Company and as a result the Company has established a full valuation allowance against its deferred tax assets with the exception of certain foreign deferred tax assets. The Company’s valuation allowance decreased by $0.1 million in 2013 and increased by $5.4 million in 2012. As of December 31, 2013 and 2012, respectively, the valuation allowance included $0.1 million related to excess tax benefits of stock option deductions prior to the adoption of ASC Topic 718. The benefits will increase additional paid-in capital when realized.
	As of December 31, 2013, the Company had U.S. federal and state net operating losses of approximately $550.1 million and $174.2 million, respectively. The U.S. federal net operation loss carryforwards will expire at various dates beginning in 2018 and through 2031 if not utilized. The state net operation loss carryforwards will expire at various dates beginning in 2014 and through 2031, if not utilized. As of December 31, 2013 and 2012, the Company had $37.2 million and $36.3 million in federal deductions, respectively, and $34.0 million and $33.3 million in state deductions, respectively, related to excess tax benefits from stock options which are not included in the net operation loss carryforward amounts in the table above since they have not met the realization criteria of ASC Topic 718. The tax benefits from these deductions will increase additional paid-in capital when realized. Additionally, the Company has U.S. federal, California and other various U.S. states research and development credits of approximately $18.5 million, $22.0 million and $1.8 million as of December 31, 2013, respectively. The U.S. federal research and development credits will begin to expire in 2020 and through 2033, and the California research and development credits have no expiration date. The credits related to other various U.S. states will begin to expire in 2015 and through 2028. During 2013, the Company performed a Section 382 study of the Internal Revenue Code (and similar state provisions) through December 31, 2012, which resulted in no adjustment of the Company’s net operation loss carryforwards.
	Uncertain Tax Positions
	ASC Topic 740, “Income Taxes,” prescribes a recognition threshold and measurement attribute to the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. The guidance also provides guidance on derecognition, classification, accounting in interim periods and disclosure requirements for uncertain tax positions. The standard requires the Company to recognize the financial statement effects of an uncertain tax position when it is more likely than not that such position will be sustained upon audit. The Company recognizes accrued interest and penalties related to unrecognized tax benefits as interest expense and income tax expense, respectively, in statements of operations.
	The following table reconciles the Company's unrecognized tax benefits for the years ended December 31, 2013 and 2012 (in thousands):
		Years Ended December 31,
		2013				2012
	Balance at beginning of period	$	13,238			$	12,543
	Additions for tax positions related to prior year	317				228
	Reductions for tax positions related to prior year	(48		)		(37		)
	Additions for tax positions related to current year	990				504
	Reductions from a lapse of applicable statute of limitations	(115		)		—
	Balance at end of period	$	14,382			$	13,238
	The total amount of unrecognized tax benefits that would affect the Company’s effective tax rate is none and $0.1 million as of December 31, 2013 and December 31, 2012, respectively. There were no accrued interest or penalties for uncertain income tax as of December 31, 2013.
	The Company files tax returns in the United State and various state jurisdictions, the United Kingdom and China. The tax years 1999 through 2013 remain open and subject to examination by the appropriate governmental agencies in the U.S. due to tax attribute carryforwards.

Segment_Information_Notes

Segment Information (Notes)	12 Months Ended
	Dec. 31, 2013
Segment Reporting [Abstract]	'
Segment Information	'
	12. Segment Information
	The Company develops, markets and sells communications access systems and software, and there are no segment managers who are held accountable for operations, operating results and plans for levels or components below the Company unit level. Accordingly, the Company is considered to be in a single reporting segment and operating unit structure. The Company’s chief operating decision maker is the Company’s Chief Executive Officer, who reviews financial information presented on a Company-wide basis, accompanied by disaggregated information about revenues by geographic region for purposes of allocating resources and evaluating financial performance.
	Geographic Information:
	The following is a summary of revenues by geographic region based upon the location of the customers (in thousands):
		Years Ended December 31,
		2013		2012		2011
	United States	$	333,403	$	306,003	$	323,070
	Caribbean	17,466		9,343		12,837
	Europe	17,397		268		211
	Canada	10,231		10,894		6,691
	Other	4,121		3,710		1,860
	Total	$	382,618	$	330,218	$	344,669
	The Company's property and equipment, net of accumulated depreciation, are located in the following geographical areas (in thousands):
		As of December 31,
		2013		2012		2011
	United States	$	14,969	$	18,390	$	14,339
	China	2,504		2,693		1,791
	Total	$	17,473	$	21,083	$	16,130

Quarterly_Financial_Data_Unaud

Quarterly Financial Data - Unaudited (Notes)	12 Months Ended
	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'
Quarterly Financial Data - Unaudited	'
	13. Quarterly Financial Data—Unaudited
	The Company's fiscal year begins on January 1st and ends on December 31st. Quarterly periods are based on a 4-4-5 fiscal calendar with the first, second and third fiscal quarters ending on the 13th Saturday of each fiscal period. As a result, the Company had two fewer days in the first quarter of 2013 and one more day in the fourth quarter of 2013 than in the respective 2012 periods.
	The following table presents selected unaudited quarterly financial data of the Company (in thousands, except per share data). The Company’s quarterly results of operations for these periods are not necessarily indicative of future results of operations.
		Fiscal Year 2013 Quarter Ended
		30-Mar			29-Jun			28-Sep			December 31 (1)
	Revenue	$	90,548		$	94,439		$	103,628		$	94,003
	Gross profit	41,115			42,505			47,407			40,047
	Operating loss	(5,540		)	(4,845		)	(12		)	(8,056		)
	Net income (loss)	(6,203		)	(5,153		)	544			(6,453		)
	Net income (loss) per common share, basic	$	(0.13	)	$	(0.10	)	$	0.01		$	(0.13	)
	Net income (loss) per common share, diluted	$	(0.13	)	$	(0.10	)	$	0.01		$	(0.13	)
		Fiscal Year 2012 Quarter Ended
		31-Mar			30-Jun			29-Sep			December 31 (2)
	Revenue	$	78,565		$	78,928		$	81,301		$	91,424
	Gross profit	33,819			33,221			33,506			37,030
	Operating loss	(7,369		)	(6,830		)	(7,077		)	(7,748		)
	Net loss	(7,521		)	(7,091		)	(7,140		)	(6,574		)
	Net loss per common share, basic and diluted	$	(0.16	)	$	(0.15	)	$	(0.15	)	$	(0.14	)
	(1) For the fourth quarter of 2013, net loss included $1.7 million of gain from utilization of inventory credit from Ericsson. See Note 2, "Business Combinations" of these Notes to the Consolidated Financial Statements for details of the Ericsson Credit.
	(2) The Company acquired Ericsson's fiber access assets in November 2012. The quarterly financial data included the results of this acquisition only for periods subsequent to the acquisition date. See Note 2, “Business Combinations" of these Notes to the Consolidated Financial Statements for details of this acquisition. For the fourth quarter of 2012, operating loss included $1.4 million of acquisition-related expenses and net loss included $1.0 million of gain from bargain purchase of Ericsson's fiber access assets.

Schedule_II_Valuation_and_Qual

Schedule II. Valuation and Qualifying Accounts (Notes)	12 Months Ended
	Dec. 31, 2013
Valuation and Qualifying Accounts [Abstract]	'
Schedule II. Valuation and Qualifying Accounts	'
	Schedule II. Valuation and Qualifying Accounts
				Additions
				Charged to
		Balance		Costs or			Deductions
		At Beginning		Expenses or			and Write			Balance At
		of Year		Revenue			Offs			End of Year
		(In thousands)
	Year ended December 31, 2013
	Allowance for doubtful accounts	$	421	$	(13	)	$	(50	)	$	358
	Product return reserve	1,740		3,535			(4,511		)	764
	Year ended December 31, 2012
	Allowance for doubtful accounts	$	402	$	112		$	(93	)	$	421
	Product return reserve	835		5,474			(4,569		)	1,740
	Year ended December 31, 2011
	Allowance for doubtful accounts	$	617	$	130		$	(345	)	$	402
	Product return reserve	551		4,996			(4,712		)	835

Description_of_Business_and_Si1

Description of Business and Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Company	'
	Company
	Calix, Inc. (together with its subsidiaries, “Calix,” the “Company,” “our,” “we,” or “us”) was incorporated in August 1999, and is a Delaware corporation. The Company is a leading provider in North America of broadband communications access systems and software for fiber- and copper-based network architectures that enable communications service providers ("CSPs") to transform their networks and connect to their residential and business subscribers. The Company enables CSPs to provide a wide range of revenue-generating services, from basic voice and data to advanced broadband services, over legacy and next-generation access networks. The Company focuses solely on CSP access networks, the portion of the network that governs available bandwidth and determines the range and quality of services that can be offered to subscribers. The Company develops and sells carrier-class hardware and software products, which the Company refers to as the Unified Access portfolio that are designed to enhance and transform CSP access networks to meet the changing demands of subscribers rapidly and cost-effectively.
Basis of Presentation	'
	Basis of Presentation
	The Company's fiscal year begins on January 1st and ends on December 31st. Quarterly periods are based on a 4-4-5 fiscal calendar with the first, second and third fiscal quarters ending on the 13th Saturday of each fiscal period.
	The accompanying consolidated financial statements, including the accounts of Calix, Inc. and its wholly owned subsidiaries, have been prepared in accordance with the requirements of the U.S. Securities and Exchange Commission (“SEC”). In the opinion of management, the consolidated financial statements include all normal and recurring adjustments that are considered necessary for the fair presentation of the Company’s financial position and operating results. All significant intercompany balances and transactions have been eliminated in consolidation.
Applicable Accounting Guidance	'
	Applicable Accounting Guidance
	Any reference in these notes to applicable accounting guidance (“guidance”) is meant to refer to the authoritative U.S. generally accepted accounting principles ("GAAP") as found in the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”).
Use of Estimates	'
	Use of Estimates
	The preparation of financial statements is in conformity with U.S. GAAP, which requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. For the Company, these estimates include, but are not limited to: allowances for doubtful accounts and sales returns, excess and obsolete inventory, allowances for obligations to its contract manufacturers, valuation of stock-based compensation, useful lives assigned to long-lived assets and acquired intangible assets, warranty costs, and contingencies. Actual results could differ from those estimates, and such differences could be material to the Company's financial position and results of operations.
Business Combination	'
	Business Combination
	The Company accounted for its business acquisitions under ASC Topic 805, “Business Combinations” ("ASC Topic 805"). Under this guidance all of the assets acquired and liabilities assumed are recognized at their fair value as of the acquisition date. The excess of the purchase price over the estimated fair values of the net tangible and intangible assets acquired is recorded as goodwill. If a business combination results in a bargain purchase for the Company, the economic gain resulting from the fair value received being greater than the purchase price is recorded as a gain that is included in other income (expense), net in the Consolidated Statements of Comprehensive Loss. Prior to recognizing the gain, the Company reassesses whether it has correctly identified all of the assets acquired and liabilities assumed and recognizes any additional assets or liabilities that result from that review. The Company also reviews the measurement procedures used in valuing the assets acquired and liabilities assumed.
	While the Company uses its best estimates and assumptions as a part of calculating the fair value at the acquisition date, the Company's estimates are inherently uncertain and subject to refinement. As a result, during the measurement period, which maybe up to one year from the acquisition date, the Company may record adjustments retrospectively to the fair value of assets acquired and liabilities assumed, with the corresponding offset to goodwill, or records a corresponding other income or expense in the case of a bargain purchase. Upon the conclusion of the measurement period or final determination of the fair value of assets acquired or liabilities assumed, whichever comes first, any subsequent adjustments are recorded to the Company's Consolidated Statements of Comprehensive Loss.
	Transaction costs associated with the business combinations are expensed as incurred, and are included in acquisition-related expenses within operating expenses in the Consolidated Statements of Comprehensive Loss.
Revenue Recognition	'
	Revenue Recognition
	The Company derives revenue primarily from the sale of hardware products and related software. Revenue is recognized when all of the following criteria have been met:
	•	Persuasive evidence of an arrangement exists.   The Company generally relies upon sales agreements and customer purchase orders as evidence of an arrangement.
	•	Delivery has occurred.  The Company uses the shipping terms of the arrangement or evidence of customer acceptance to verify delivery or performance.
	•	Sales price is fixed or determinable.   The Company assesses whether the sales price is fixed or determinable based on the payment terms and whether the sales price is subject to refund or adjustment. Payment terms to customers can range from net 30 to net 120 days.
	•	Collectability is reasonably assured.  The Company assesses collectability based primarily on creditworthiness of customers and their payment histories.
	Revenue from installation and training services are recognized as the services are completed. Post-sales software support revenue and extended warranty services revenue are deferred and recognized ratably over the period during which the services are to be performed. To date, service revenue has comprised an insignificant portion of the Company's revenue and the Company has not reported service revenue separately from product revenue in its financial statements. In instances where substantive acceptance provisions are specified in the customer agreement, revenue is deferred until all acceptance criteria have been met. From time to time, the Company offers customers sales incentives, which include volume rebates and discounts. These amounts are estimated on a quarterly basis and recorded as a reduction of revenue.
	The Company enters into arrangements with certain of its customers who receive government supported loans and grants from the U.S. Department of Agriculture's Rural Utility Service (“RUS”) to finance capital spending. Under the terms of an RUS equipment contract that includes installation services, the customer does not take possession and control and title does not pass until formal acceptance is obtained from the customer. Under this type of arrangement, the Company does not recognize revenue until it has received formal acceptance from the customer. For RUS arrangements that do not involve installation services, the Company recognizes revenue in accordance with the revenue recognition policy described above.
	The Company's products contain both software and non-software components that function together to deliver the products' essential functionality. When the Company enters into sales arrangements that consist of multiple deliverables of its product and service offerings, the Company allocates the total consideration of the arrangement to each separable deliverable based on its relative selling price. The Company limits the amount allocable to delivered elements to the amount that is not contingent upon the delivery of additional items or meeting specified performance conditions, and recognizes revenue on each deliverable in accordance with its revenue recognition policy. The determination of selling price for each deliverable is based on a selling price hierarchy, which is vendor-specific objective evidence (“VSOE”) if available, third-party evidence (“TPE”) if VSOE is not available, or estimated selling price (“ESP”) if neither VSOE nor TPE is available. VSOE of selling price is based on the price charged when the element is sold separately. In determining VSOE, the Company requires that a substantial majority of the selling prices of an element fall within a narrow range when each element is sold separately. The Company has established VSOE for its training and post-sales software support services based on the normal pricing practices of these services when sold separately. TPE of selling price is established by evaluating whether there are similar competitor products or services that are sold in stand-alone sales transaction to similarly situated customers. Generally, the Company's marketing strategy differs from that of its peers and its offerings contain a significant level of customization and differentiation such that the comparable pricing of products with similar functionality cannot be obtained. Additionally, as the Company is unable to reliably determine what similar competitor products' selling prices are on a stand-alone basis, it is not typically able to determine TPE. ESP is established considering multiple factors including, but not limited to geographies market conditions, competitive landscape, internal costs, gross margin objectives, characteristics of targeted customers and pricing practices. The determination of ESP is made through consultation with and formal approval by management, taking into consideration the go-to-market strategy.
Cost of Revenue	'
	Cost of Revenue
	Cost of revenue consists primarily of finished goods inventory purchased from the Company’s contract manufacturers, payroll and related expenses associated with managing the relationships with contract manufacturers, depreciation of manufacturing test equipment, warranty costs, excess and obsolete inventory costs, shipping charges, and amortization of certain intangible assets. For the year ended December 31, 2011, cost of revenue also includes acquisition-related expenses associated with the acquisition of Occam primarily related to a charge resulting from the required revaluation of Occam inventory to its estimated fair value and an associated write-down of acquired inventory determined as excess and obsolete.
Stock-based Compensation	'
	Stock-Based Compensation
	In accordance with ASC Topic 718, "Compensation - Stock Compensation" ("ASC Topic 718"), stock-based awards are recorded at fair value as of the grant date and recognized to expense over the employee’s requisite service period (generally the vesting period), which the Company has elected to amortize on a straight-line basis. Stock-based compensation expense is reduced by the Company’s estimated forfeitures on all unvested awards.
	The fair value of stock option and employee stock purchase right is estimated at the grant date using the Black-Scholes option valuation model. The fair value of restricted stock unit and restricted stock award is based on the closing market price of the Company's common stock on the date of grant. The fair value of performance restricted stock unit ("PRSU") with a market condition is estimated on the date of grant, using a Monte Carlo simulation model to estimate the total return ranking of the Company's stock in relation to the peer group over each performance period. Compensation cost on PRSUs with a market condition is not adjusted for subsequent changes in the Company's stock performance or the level of ultimate vesting.
Warranty	'
	Warranty
	The Company offers limited warranties for its hardware products for a period of one or five years, depending on the product type. Warranty service revenues are deferred and recognized ratably over the period during which the services are to be performed. The Company recognizes estimated costs related to warranty activities as a component of cost of revenue upon product shipment. The estimates are based on historical product failure rates and historical costs incurred in correcting product failures. The recorded amount is adjusted from time to time for specifically identified warranty exposure. Actual warranty expenses are charged against the Company’s estimated warranty liability when incurred. Factors that affect the Company’s warranty liability include the number of installed units and historical and anticipated rates of warranty claims and cost per claim.
Research and Development	'
	Research and Development
	Research and development costs include costs of developing new products and processes, as well as design and engineering costs. Such costs are charged to research and development expense as incurred.
	Development costs related to software incorporated in the Company’s products incurred subsequent to the establishment of technological feasibility are capitalized and amortized over the estimated useful lives of the related products. Technological feasibility is established upon completion of a working model.
Credit Risk and Inventory Supplier Concentrations	'
	Credit Risk and Inventory Supplier Concentrations
	Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash and cash equivalents and accounts receivable. Cash equivalents consist of money market funds, which are invested through financial institutions in the United States. Deposits in these financial institutions may, at times, exceed federally insured limits. The Company has not experienced any losses in such accounts. The Company also has approximately $2.8 million of cash held by its foreign subsidiaries in China and the United Kingdom. Management believes that the financial institutions that hold the Company’s cash and cash equivalents are financially sound and, accordingly, minimal credit risk exists with respect to these cash and cash equivalents.
	Concentrations of credit risk in relation to customers with an accounts receivable balance of 10% or greater of total accounts receivable and customers with net revenues of 10% or greater of total revenues are presented below for the periods indicated.
			Percentage of Accounts Receivable		Percentage of Revenue
			At December 31,		Years Ended December 31,
			2013	2012	2013	2012	2011
	CenturyLink		15%	13%	26%	21%	20%
	Ericsson (1)		12%	*	*	*	*
	(1) Includes certain of Ericsson's consolidated subsidiaries.
	* Less than 10% of total accounts receivable or revenue.
	The Company maintains an allowance for doubtful accounts for estimated losses resulting from the inability of its customers to make required payments. The Company records a specific allowance based on an analysis of individual past-due balances. Additionally, based on its historical write-offs and collections experience, the Company records an additional allowance based on a percentage of outstanding receivables. The Company performs credit evaluations of its customers’ financial condition. These evaluations require significant judgment and are based on a variety of factors including, but not limited to, current economic trends, payment history and financial review of the customer. Actual collection losses may differ from management’s estimates, and such differences could be material to the Company’s financial position and results of operations.
	The Company depends primarily on a small number of outside contract manufacturers for the bulk of its finished goods inventory. In particular, the Company relies on Flextronics for the manufacture of most of its products. The Company generally purchases its products through purchase orders with its suppliers or contract manufacturers. While the Company seeks to maintain a sufficient reserve of its products, the Company’s business and results of operations could be adversely affected by a stoppage or delay in receiving such products, the receipt of defective parts, an increase in price of such products or the Company’s inability to obtain lower prices from its contract manufacturers and suppliers in response to competitive pressures.
Fair Value of Financial Instruments	'
	Fair Value of Financial Instruments
	The carrying amounts of cash and cash equivalents, trade receivables, marketable securities, accounts payable, and other accrued liabilities approximate their fair value due to their relatively short-term nature. The carrying amount of the other long-term liabilities approximates its fair value.
Cash, Cash Equivalents, and Marketable Securities	'
	Cash, Cash Equivalents, and Marketable Securities
	The Company has invested its excess cash primarily in money market funds in 2013 and 2012. Before 2012, the Company also invested some cash in highly liquid debt instruments. The Company considers all investments with maturities of three months or less when purchased to be cash equivalents. Marketable securities represent highly liquid debt instruments with maturities greater than 90 days at date of purchase. Cash, cash equivalents and marketable securities are stated at amounts that approximate fair value based on quoted market prices.
	The Company’s investments have been classified and accounted for as available-for-sale. Such investments are recorded at fair value and unrealized holding gains and losses are reported as a separate component of comprehensive loss in the stockholders’ equity until realized. Should the Company determine that any unrealized losses on the investments are other-than-temporary, the amount of that impairment to be recognized in earnings will depend on whether the Company intends to sell the security or more likely than not will be required to sell the security before recovery of its amortized cost basis less any current period credit loss. During 2011, all of the Company's marketable securities had been sold or matured. Realized gains and losses, which have been immaterial, are determined on the specific identification method and are reflected in results of operations.
Restricted Cash	'
	Restricted Cash
	As of December 31, 2013, the Company had $0.3 million cash restricted for collateralizing the outstanding letters of credit with Silicon Valley Bank. As of December 31, 2012, there were no restricted cash balances.
Inventory	'
	Inventory
	Inventory, which primarily consisted of finished goods purchased from contract manufacturers, is stated at the lower of cost, determined by the first-in, first-out method, or market value. Inbound shipping costs are included in cost of inventory. In addition, the Company, from time to time, procures component inventory primarily as a result of manufacturing discontinuation of critical components by suppliers. The Company regularly monitors inventory quantities on hand and records write-downs for excess and obsolete inventories based on the Company’s estimate of demand for its products, potential obsolescence of technology, product life cycles, and whether pricing trends or forecasts indicate that the carrying value of inventory exceeds its estimated selling price. These factors are impacted by market and economic conditions, technology changes, and new product introductions and require estimates that may include elements that are uncertain. Actual demand may differ from forecasted demand and may have a material effect on gross margins. If inventory is written down, a new cost basis is established that cannot be increased in future periods. Shipments from our suppliers or contract manufacturers before the Company receives them are recorded as in-transit inventory when title and the significant risks and rewards of ownership have passed to the Company.
Deferred Cost of Revenue	'
	Deferred Cost of Revenue
	When the Company’s products have been shipped, but the product revenue associated with the arrangement has been deferred as a result of not meeting the criteria for immediate revenue recognition, the Company also defers the related inventory costs for the delivered items until all criteria are met for revenue recognition. Deferred cost of revenue also includes installation service costs related to customer installation projects in which the revenue has been deferred until completion of the project and, to a lesser extent, trial orders that are pending acceptance.
Property and Equipment	'
	Property and Equipment
	Property and equipment are stated at cost, less accumulated depreciation, and are depreciated using the straight-line method over the estimated useful life of each asset. Computer equipment is depreciated over two years; purchased software is depreciated over three years; test equipment is depreciated over three years; furniture and fixtures are depreciated over seven years; and leasehold improvements are depreciated over the shorter of the respective lease term or the estimated useful life of the asset. Maintenance and repairs are charged to expense as incurred.
Goodwill	'
	Goodwill
	The Company records goodwill when consideration paid in a business acquisition exceeds the fair value of the net tangible assets and the identified intangible assets acquired. Goodwill is not amortized but instead is subject to an annual impairment test or more frequently if events or changes in circumstances indicate that it may be impaired. The Company evaluates goodwill on an annual basis as of the end of the second quarter of each fiscal year. Management has determined that it operates as a single reporting unit and, therefore, evaluates goodwill impairment at the enterprise level.
	In an annual impairment test, the Company first assesses qualitative factors to determine whether it is necessary to perform the two-step quantitative goodwill impairment test. In assessing the qualitative factors, management considers the impact of these key factors: macro-economic conditions, industry and market environment, overall financial performance of the Company, cash flow from operating activities, market capitalization and stock price. If the Company determines as a result of the qualitative assessment that it is more likely than not that the fair value of a reporting unit is less than its carrying amount, then the quantitative test is required. Otherwise, no further testing is required.
	In a quantitative test, the Company compares its fair value to its carrying value including goodwill. The Company determines its fair value using both an income approach and a market approach. Under the income approach, the Company determines fair value based on estimated future cash flows, discounted by an estimated weighted-average cost of capital, which reflects the overall level of inherent risk of the Company and the rate of return an outside investor would expect to earn. Under the market-based approach, the Company utilizes information regarding the Company as well as publicly available industry information to determine earnings multiples that are used to value the Company. If the carrying value of the Company exceeds its fair value, the Company will determine the amount of impairment loss by comparing the implied fair value of goodwill with the carrying value of goodwill. An impairment charge is recognized for the excess of the carrying value of goodwill over its implied fair value.
	At the end of the second quarter of 2013, the Company has completed its annual goodwill impairment test. Based on its assessment of the aforementioned qualitative factors, management concluded that the fair value of the Company was more likely than not greater than its carrying amount as of June 29, 2013. As such, it was not necessary to perform the two-step quantitative goodwill impairment test at the time. Subsequent to the 2013 annual impairment test, there have been no significant events or circumstances affecting the valuation of goodwill. As of December 31, 2013, there was no impairment to the carrying value of the Company's goodwill. There were no impairment losses for goodwill during 2012 and 2011.
Intangible Assets and Other Long-Lived Assets	'
	Intangible Assets and Other Long-Lived Assets
	Intangible assets with finite useful lives are amortized over their estimated useful life, generally five years. The Company periodically evaluates long-lived assets, including intangible assets, for impairment whenever events or changes in circumstances indicate that a potential impairment may have occurred. If such events or changes in circumstances arise, the Company compares the carrying amount of the long-lived assets to the estimated future undiscounted cash flows expected to be generated by the long-lived assets. If the estimated aggregate undiscounted cash flows are less than the carrying amount of the long-lived assets, an impairment charge, calculated as the amount by which the carrying amount of the assets exceeds the fair value of the assets, is recorded. The fair value of long-lived assets is determined based on the estimated discounted cash flows expected to be generated from the assets. The Company has reviewed events and changes to its business during the year and has determined that there was no impairment to its intangible assets and other long-lived assets during 2013. The Company did not incur any impairment losses for intangible assets and other long-lived assets during 2012 and 2011.
Income Taxs	'
	Income Taxes
	The Company evaluates its tax positions and estimates its current tax exposure along with assessing temporary differences that result from different book to tax treatment of items not currently deductible for tax purposes. These differences result in deferred tax assets and liabilities on the Company’s balance sheets, which are estimated based upon the difference between the financial statement and tax bases of assets and liabilities using the enacted tax rates that will be in effect when these differences reverse. In general, deferred tax assets represent future tax benefits to be received when certain expenses previously recognized in the Company’s statements of operations become deductible expenses under applicable income tax laws or loss or credit carryforwards are utilized. Accordingly, realization of the Company’s deferred tax assets is dependent on future taxable income against which these deductions, losses and credits can be utilized.
	The Company must assess the likelihood that the Company’s deferred tax assets will be recovered from future taxable income, and to the extent the Company believes that recovery is not more likely than not, the Company must establish a valuation allowance. Management judgment is required in determining the Company’s provision for income taxes, the Company’s deferred tax assets and liabilities and any valuation allowance recorded against the Company’s net deferred tax assets. Excluding our foreign operations, the Company recorded a full valuation allowance at each balance sheet date presented because, based on the available evidence, the Company believes it is more likely than not that it will not be able to utilize all of its deferred tax assets in the future. The Company intends to maintain the full valuation allowances until sufficient evidence exists to support the reversal of the valuation allowances.
Foreign Currency Translation	'
	Foreign Currency Translation
	Assets and liabilities of the Company’s wholly owned foreign subsidiaries are translated from their respective functional currencies at exchange rates in effect at the balance sheet date, and revenues and expenses are translated at the monthly average exchanges rates. Any material resulting translation adjustments are reflected as a separate component of stockholders’ equity. Realized foreign currency transaction gains and losses were not significant during the years ended December 31, 2013, 2012 and 2011.
Recently Adopted Accounting Guidance	'
	Recent Accounting Pronouncements
	In July 2013, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update No. 2013-11, Income Taxes (Topic 740): Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists (a consensus of the FASB Emerging Issues Task Force) ("ASU 2013-11"), which provides explicit guidance on the financial statement presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss or a tax credit carryforward exists. Under the new standard update, in most circumstances, an unrecognized tax benefit should be presented in the Company's financial statements as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss or a tax credit carryforward. The amendments should be applied prospectively to all unrecognized tax benefits that exist at the effective date. Retrospective application is permitted. ASU 2013-11 will be effective for the Company beginning in the first quarter of fiscal 2014. The Company does not expect adoption of this guidance to have a material impact on its financial statements.
	In February 2013, the FASB issued Accounting Standards Update No. 2013-02, Comprehensive Income (Topic 220): Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income ("ASU 2013-02"), to improve the reporting of reclassifications out of accumulated other comprehensive income. ASU 2013-02 requires an entity to report the effect of significant reclassifications out of accumulated other comprehensive income on the respective line items in net income if the amount being reclassified is required under U.S. GAAP to be reclassified in its entirety to net income. For other amounts that are not required under U.S. GAAP to be reclassified in their entirety from accumulated other comprehensive income to net income in the same reporting period, an entity is required to cross-reference other disclosures required under U.S. GAAP that provide additional detail about those amounts. ASU 2013-02 was effective for the Company in its first quarter of fiscal 2013 and was applied prospectively. Other than requiring additional disclosures, adoption of this guidance did not have an impact on the financial statements of the Company.

Description_of_Business_and_Si2

Description of Business and Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Schedule of Customer Concentration Risk	'
	Concentrations of credit risk in relation to customers with an accounts receivable balance of 10% or greater of total accounts receivable and customers with net revenues of 10% or greater of total revenues are presented below for the periods indicated.
		Percentage of Accounts Receivable		Percentage of Revenue
		At December 31,		Years Ended December 31,
		2013	2012	2013	2012	2011
	CenturyLink	15%	13%	26%	21%	20%
	Ericsson (1)	12%	*	*	*	*
	(1) Includes certain of Ericsson's consolidated subsidiaries.
	* Less than 10% of total accounts receivable or revenue.

Business_Combinations_Tables

Business Combinations (Tables)	12 Months Ended
	Dec. 31, 2013
EFAA Acquisition [Member]	'
Business Acquisition [Line Items]	'
Assets Acquired and Liabilities Assumed	'
	The Company finalized the fair values of the acquired assets and assumed liabilities from Ericsson, as summarized in the following table (in thousands), and closed the measurement period in 2013.
		At November 2, 2012
	Inventory	$	9,361
	Other current asset	739
	Property and equipment	3,616
	Other current liabilities	(124		)
	Deferred tax liability	(563		)
	Net assets acquired	13,029
	Gain on bargain purchase	(1,029		)
	Total purchase price	$	12,000
Occam Acquisition [Member]	'
Business Acquisition [Line Items]	'
Valuation Assumptions, Stock Options	'
	The following table represents the weighted average assumptions used to estimate fair value of stock options:
		At February 22, 2011
	Expected volatility	52%
	Expected life (years)	3.95
	Expected dividend yield	—
	Risk-free interest rate	1.65%
Assets Acquired and Liabilities Assumed	'
	The following table summarizes the fair value of the acquired assets and assumed liabilities related to the acquisition of Occam (in thousands):
		At February 22, 2011
	Cash and cash equivalents	$	33,631
	Restricted cash	1,054
	Accounts receivable	16,854
	Inventory	29,229
	Prepaid expenses and other assets	854
	Property and equipment	7,363
	Intangible assets:
	Trade name (useful life of 6 months)	2,290
	Customer relationships (useful life of 5 years)	51,040
	Core developed technology (useful life of 5 years)	25,494
	In-process technology	16,270
	Purchase order backlog (useful life of 10 months)	2,560
	Total intangible assets	97,654
	Goodwill	50,599
	Current liabilities	(22,414		)
	Deferred revenue	(866		)
	Long-term liabilities	(890		)
	Total	$	213,068

Goodwill_and_Intangible_Assets1

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'
Summary of intangible assets	'
	The details of intangible assets as of December 31, 2013 and December 31, 2012 are disclosed in the following table (in thousands):
			31-Dec-13							31-Dec-12
			Gross		Accumulated			Net		Gross		Accumulated			Net
			Carrying		Amortization					Carrying		Amortization
			Amount							Amount
	Core developed technology		$	68,964	$	(47,339	)	$	21,625	$	68,964	$	(38,986	)	$	29,978
	Customer relationships		54,740		(32,625		)	22,115		54,740		(22,417		)	32,323
	Total intangible assets, excluding goodwill		$	123,704	$	(79,964	)	$	43,740	$	123,704	$	(61,403	)	$	62,301
Summary of expected future amortization	'
	Expected future amortization expense for the fiscal years indicated is as follows (in thousands):
	Period	Expected Amortization Expense
	2014	$	18,561
	2015	18,561
	2016	5,805
	2017	813
	Total	$	43,740

Balance_Sheet_Details_Tables

Balance Sheet Details (Tables)	12 Months Ended
	Dec. 31, 2013
Balance Sheet Related Disclosures [Abstract]	'
Cash and Cash Equivalents Details	'
	Cash and cash equivalents consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Cash	$	62,905		$	27,157
	Money market funds	19,842			19,838
	Total cash and cash equivalents	$	82,747		$	46,995
Accounts Receivable, net, Details	'
	Accounts receivable, net consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Accounts receivable	$	44,642		$	61,680
	Allowance for doubtful accounts	(358		)	(421		)
	Product return reserve	(764		)	(1,740		)
	Accounts receivable, net	$	43,520		$	59,519
Inventory Details	'
	Inventory consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Raw materials	$	6,591		$	9,377
	Finished goods	44,480			33,905
	Total inventory	$	51,071		$	43,282
Property and Equipment, net, Details	'
	Property and equipment, net consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Test equipment	$	36,932		$	37,595
	Computer equipment and purchased software	27,280			31,582
	Furniture and fixtures	1,614			1,470
	Leasehold improvements	7,077			6,763
	Total	72,903			77,410
	Accumulated depreciation and amortization	(55,430		)	(56,327		)
	Property and equipment, net	$	17,473		$	21,083
Accrued Liabilities Details	'
	Accrued liabilities consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Accrued compensation and related benefits	$	13,127		$	12,906
	Accrued warranty	10,856			11,762
	Accrued professional and consulting fees	1,634			1,740
	Accrued excess and obsolete inventory at contract manufacturers	756			1,357
	Accrued customer rebates	712			1,565
	Accrued business travel expenses	540			593
	Sales and use tax payable	521			929
	Income taxes payable	368			627
	Accrued other	3,561			4,697
	Total accrued liabilities	$	32,075		$	36,176
Deferred Revenue Details	'
	Deferred revenue consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Deferred Revenue:
	Product and services - current	$	32,051		$	36,715
	Extended warranty - current	2,811			2,600
	Extended warranty - non-current	18,335			15,711
	Product and services - non-current	96			71
	Total deferred revenue	$	53,293		$	55,097
Accumulated Other Comprehensive Income (Loss) Details	'
	The following table provides the balances and changes in the components of accumulated other comprehensive income (loss) for the years indicated (in thousands):
		Foreign Currency Translation Adjustments			Unrealized Gain (Loss) on Investments			Accumulated Other Comprehensive Income
	Balance at 12/31/2010	$	10		$	21		$	31
	Current period other comprehensive income (loss)	88			(21		)	67
	Balance at 12/31/2011	98			—			98
	Current period other comprehensive income	34			—			34
	Balance at 12/31/2012	132			—			132
	Current period other comprehensive income	58			—			58
	Balance at 12/31/2013	$	190		$	—		$	190

Commitments_and_Contingencies_1

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]	'
Schedule of Future Minimum Rental Payments for Operating Leases	'
	Future minimum payments under the non-cancelable operating leases consisted of the following as of December 31, 2013 (in thousands):
	Period	Minimum Future Lease Payments
	2014	$	3,438
	2015	2,743
	2016	2,252
	2017	2,177
	2018	1,894
	Thereafter	252
	Total	$	12,756
Product warranty activities [Roll Forward]	'
	Changes in the Company’s warranty reserve in the periods as indicated were as follows (in thousands):
		Years Ended December 31,
		2013			2012			2011
	Balance at beginning of period	$	11,762		$	12,104		$	3,789
	Accrued warranty from the Occam acquisition	—			—			8,500
	Warranty charged to cost of revenue	4,350			4,701			5,883
	Utilization of warranty	(5,256		)	(5,043		)	(6,068		)
	Balance at end of period	$	10,856		$	11,762		$	12,104

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Summary of fair values of financial assets	'
	The following table sets forth the Company's financial assets measured at fair value as of December 31, 2013 and December 31, 2012, based on the three-tier fair value hierarchy (in thousands):
	As of December 31, 2013	Level 1		Total
	Money market funds	$	19,842	$	19,842
	Total	$	19,842	$	19,842
	As of December 31, 2012	Level 1		Total
	Money market funds	$	19,838	$	19,838
	Total	$	19,838	$	19,838

Net_Loss_per_Share_Tables

Net Loss per Share (Tables)	12 Months Ended
	Dec. 31, 2013
Earnings Per Share [Abstract]	'
Schedule of net loss per share	'
	The following table sets forth the computation of basic and diluted net loss per share for the periods indicated (in thousands, except per share data):
		Years Ended December 31,
		2013			2012			2011
	Numerator:
	Net loss	$	(17,265	)	$	(28,326	)	$	(52,550	)
	Denominator:
	Weighted-average common shares outstanding	49,419			48,180			45,546
	Basic and diluted net loss per common share	$	(0.35	)	$	(0.59	)	$	(1.15	)
	Potentially dilutive shares, weighted-average	5,308			4,454			3,695

Stockholders_Equity_Tables

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2013
Stockholders' Equity Note [Abstract]	'
Schedule of Stock Options Activity	'
	The following table summarizes the activity of stock options under the Company’s equity incentive plans (in thousands, except per share data):
						Weighted-				Weighted-Average
						Average				Remaining		Aggregate
			Number of			Exercise Price				Contractual Life		Intrinsic
	Stock Options		Shares			Per Share				(in years)		Value (1)
	Outstanding as of December 31, 2012		2,213			$	13.51
	Granted		573			8.57
	Exercised		(160	)		4.66
	Forfeited or expired		(66	)		13.32
	Outstanding as of December 31, 2013		2,560			$	12.96			7.6		$	2,474
	Vested and expected to vest at December 31, 2013		2,520			$	13.02			7.6		$	2,414
	(1) Amounts represent the difference between the exercise price and the fair market value of common stock at December 31, 2013 for all in the money options outstanding.
Schedule of Stock Options by Exercise Price Range	'
	The following table summarizes information about stock options outstanding and exercisable at December 31, 2013 (in thousands, except year and per share data):
									Options Outstanding									Options Exercisable
												Weighted-Average		Weighted-							Weighted-
									Number			Remaining		Average				Number			Average
									of Shares			Contractual Life		Exercise Price				of Shares			Exercise Price
	Range of Exercise Prices								Outstanding			(in years)		Per Share				Exercisable			Per Share
	$	1.2		—	$	6.8			453			7.3		$	6.31			255			$	6.12
	6.95			—	8.38				183			8.2		7.67				61			7.47
	8.41			—	8.41				467			9.1		8.41				95			8.41
	8.55			—	10.71				436			8		10.45				216			10.35
	10.85			—	18.86				508			7.2		15.58				351			15.74
	19.4			—	4,401.93				513			6.4		24.42				387			25.4
	$	1.2		—	$	4,401.93			2,560			7.6		$	12.96			1,365			$	14.94
Schedule of Restricted Stock and Restricted Stock Units Activity	'
	The following table summarizes the activities of the Company's RSUs, PRSUs, and RSAs under the Company’s equity incentive plans (in thousands, except per share data):
		RSUs							PRSUs							RSAs
					Weighted-Average							Weighted-Average							Weighted-Average
					Grant Date							Grant Date							Grant Date
		Number of			Fair Value				Number of			Fair Value				Number of			Fair Value
		Shares			Per Share				Shares			Per Share				Shares			Per Share
	Outstanding at December 31, 2012	1,762			$	11.67			183			$	14.78			299			$	21.67
	Granted	705			9.2				230			11.24				—			—
	Vested	(822	)		11.07				—			—				(95	)		21.67
	Canceled	(139	)		9.51				—			—				(15	)		21.67
	Outstanding at December 31, 2013	1,506			$	11.04			413			$	12.81			189			$	21.67
Schedule of Grant Date Fair Values	'
	The following table summarizes the weighted-average grant date fair values of the Company's stock-based awards granted in the periods indicated:
		Years Ended December 31,
		2013				2012				2011
	Stock options	$	4.89			$	4.68			$	9.77
	RSUs	$	9.2			$	6.55			$	21.33
	PRSUs	$	11.24			$	14.81			N/A
	RSAs	N/A				N/A				$	21.67
	ESPP	$	2.94			$	2.34			$	3.48
Valuation Assumptions, Stock Options	'
	The following table summarizes the weighted-average assumptions used in estimating the grant-date fair value of stock options and of each employee’s purchase right under the 2010 ESPP in the periods indicated:
		Years Ended December 31,
	Stock Options	2013			2012			2011
	Expected volatility	62	%		56	%		52	%
	Expected life (years)	6.05			6.25			6.25
	Expected dividend yield	—			—			—
	Risk-free interest rate	1.14	%		1.06	%		2.11	%
Valuation Assumptions, ESPP	'
		Years Ended December 31,
	ESPP	2013			2012			2011
	Expected volatility	50	%		63	%		52	%
	Expected life (years)	0.5			0.5			0.5
	Expected dividend yield	—			—			—
	Risk-free interest rate	0.09	%		0.13	%		0.66	%
Schedule of Unrecognized Compensation Cost	'
	As of December 31, 2013, unrecognized stock-based compensation expenses by award type, net of estimated forfeitures, and their expected weighted-average recognition periods are summarized in the following table (in thousands).
			As of December 31, 2013
			Stock Option				RSU				PRSU				RSA				ESPP
	Unrecognized stock-based compensation expense		$	6,391			$	10,861			$	1,801			$	2,392			$	662
	Weighted-average amortization period (in years)		2.2				2.3				1.3				1.5				0.4
Schedule of Warrants	'
	As of December 31, 2013, the following warrants to purchase common stock were outstanding (in thousands, except per share data):
	Expiration Date		Exercise Price				Number of Warrants Outstanding
			Per Share
	August 16, 2014		$	10.26			8
	September 4, 2017		$	19.56			15
							23
Shares Reserved For Future Issuance	'
	The Company had common shares reserved for future issuance as follows (in thousands):
		As of December 31,
		2013			2012			2011
	Stock options outstanding	2,560			2,213			1,661
	Restricted stock units outstanding	1,506			1,762			1,775
	Performance restricted stock units outstanding	413			183			—
	Shares available for future grant under 2010 Plan	3,652			3,959			4,508
	Shares available for future issuance under ESPP	2,574			3,260			579
	Common stock warrants	23			23			23
	Total	10,728			11,400			8,546

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]	'
	Provision for (benefit from) income taxes consisted of the following for the periods indicated (in thousands):
		Years Ended December 31,
		2013				2012				2011
	Federal current income tax (benefit)	$	(274	)		$	152			$	—
	State current income tax	41				73				114
	Foreign current income tax	315				440				228
	Federal deferred income tax (benefit)	—				(474		)		—
	State deferred income tax (benefit)	—				(89		)		—
	Foreign deferred income tax (benefit)	(96		)		56				(118		)
	Provision for (benefit from) income taxes	$	(14	)		$	158			$	224
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	'
	The differences between the statutory tax rate and the effective tax rate, expressed as a percentage of loss before income taxes, were as follows:
		Years Ended December 31,
		2013			2012			2011
	Federal statutory rate	34	%		34	%		34	%
	State statutory rate	3.4	%		5.2	%		5.2	%
	Foreign operations	1.4	%		0.1	%		0.2	%
	Release of FIN 48 liability and interest	0.7	%		—	%		—	%
	R&D tax credits	13.1	%		2.5	%		2.1	%
	Release of valuation allowance related to EFAA acquisition	—	%		2	%		—	%
	Acquisition-related costs	—	%		1.2	%		(1.5	)%
	Other permanent items	(4.5	)%		0.1	%		(1.6	)%
	2012 tax true-up	1	%		—	%		—	%
	Valuation allowance	(49.0	)%		(45.7	)%		(38.8	)%
	Effective tax rate	0.1	%		(0.6	)%		(0.4	)%
Schedule of Deferred Tax Assets and Liabilities	'
	The significant components of the Company’s deferred tax assets and liabilities were as follows (in thousands):
		As of December 31,
		2013				2012
	Deferred tax assets:
	Net operating loss carryforwards	$	168,431			$	180,005
	Tax credit carryforwards	22,507				20,154
	Depreciation and amortization	2,996				2,858
	Accruals and reserves	11,479				11,353
	Deferred revenue	12,037				13,367
	Stock-based compensation	5,570				3,592
	Other	450				294
	Gross deferred tax assets	223,470				231,623
	Valuation allowance	(207,315		)		(207,441		)
	Net deferred tax assets	16,155				24,182
	Deferred tax liabilities:
	Intangible assets	(15,988		)		(24,120		)
	Net deferred tax assets reflected in balance sheet	$	167			$	62
Unrecognized Tax Benefits Activity	'
	The following table reconciles the Company's unrecognized tax benefits for the years ended December 31, 2013 and 2012 (in thousands):
		Years Ended December 31,
		2013				2012
	Balance at beginning of period	$	13,238			$	12,543
	Additions for tax positions related to prior year	317				228
	Reductions for tax positions related to prior year	(48		)		(37		)
	Additions for tax positions related to current year	990				504
	Reductions from a lapse of applicable statute of limitations	(115		)		—
	Balance at end of period	$	14,382			$	13,238

Segment_Information_Tables

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2013
Segment Reporting [Abstract]	'
Revenue by Geographic Region	'
	The following is a summary of revenues by geographic region based upon the location of the customers (in thousands):
		Years Ended December 31,
		2013		2012		2011
	United States	$	333,403	$	306,003	$	323,070
	Caribbean	17,466		9,343		12,837
	Europe	17,397		268		211
	Canada	10,231		10,894		6,691
	Other	4,121		3,710		1,860
	Total	$	382,618	$	330,218	$	344,669
Property and Equipment by Geographic Region	'
	The Company's property and equipment, net of accumulated depreciation, are located in the following geographical areas (in thousands):
		As of December 31,
		2013		2012		2011
	United States	$	14,969	$	18,390	$	14,339
	China	2,504		2,693		1,791
	Total	$	17,473	$	21,083	$	16,130

Quarterly_Financial_Data_Unaud1

Quarterly Financial Data - Unaudited (Tables)	12 Months Ended
	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'
Schedule of Quarterly Financial Information [Table Text Block]	'
	The following table presents selected unaudited quarterly financial data of the Company (in thousands, except per share data). The Company’s quarterly results of operations for these periods are not necessarily indicative of future results of operations.
		Fiscal Year 2013 Quarter Ended
		30-Mar			29-Jun			28-Sep			December 31 (1)
	Revenue	$	90,548		$	94,439		$	103,628		$	94,003
	Gross profit	41,115			42,505			47,407			40,047
	Operating loss	(5,540		)	(4,845		)	(12		)	(8,056		)
	Net income (loss)	(6,203		)	(5,153		)	544			(6,453		)
	Net income (loss) per common share, basic	$	(0.13	)	$	(0.10	)	$	0.01		$	(0.13	)
	Net income (loss) per common share, diluted	$	(0.13	)	$	(0.10	)	$	0.01		$	(0.13	)
		Fiscal Year 2012 Quarter Ended
		31-Mar			30-Jun			29-Sep			December 31 (2)
	Revenue	$	78,565		$	78,928		$	81,301		$	91,424
	Gross profit	33,819			33,221			33,506			37,030
	Operating loss	(7,369		)	(6,830		)	(7,077		)	(7,748		)
	Net loss	(7,521		)	(7,091		)	(7,140		)	(6,574		)
	Net loss per common share, basic and diluted	$	(0.16	)	$	(0.15	)	$	(0.15	)	$	(0.14	)
	(1) For the fourth quarter of 2013, net loss included $1.7 million of gain from utilization of inventory credit from Ericsson. See Note 2, "Business Combinations" of these Notes to the Consolidated Financial Statements for details of the Ericsson Credit.
	(2) The Company acquired Ericsson's fiber access assets in November 2012. The quarterly financial data included the results of this acquisition only for periods subsequent to the acquisition date. See Note 2, “Business Combinations" of these Notes to the Consolidated Financial Statements for details of this acquisition. For the fourth quarter of 2012, operating loss included $1.4 million of acquisition-related expenses and net loss included $1.0 million of gain from bargain purchase of Ericsson's fiber access assets.

Description_of_Business_and_Si3

Description of Business and Significant Accounting Policies - Customer Concentration Risk (Details)	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
CenturyLink [Member]	'		'	'
Concentration Risk [Line Items]	'		'	'
Percentage of Accounts Receivable	15.00%		13.00%	'
Percentage of Revenue	26.00%		21.00%	20.00%
Ericsson [Member]	'		'	'
Concentration Risk [Line Items]	'		'	'
Percentage of Accounts Receivable	12.00%	[1]	'	'
[1]	Includes certain of Ericsson's consolidated subsidiaries.

Description_of_Business_and_Si4

Description of Business and Significant Accounting Policies - Useful Lives of Property and Equipment (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013
In Thousands, unless otherwise specified			Computer Equipment [Member]	Purchased Software [Member]	Test Equipment [Member]	Furniture and Fixtures [Member]	Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]	'	'	'	'	'	'	'
Restricted Cash and Cash Equivalents	$295	$0	'	'	'	'	'
Useful Life of Property and Equipment	'	'	'2 years	'3 years	'3 years	'7 years	'
Useful Life of Leasehold Improvements	'	'	'	'	'	'	'the shorter of the respective lease term or the estimated useful life of the asset

Description_of_Business_and_Si5

Description of Business and Significant Accounting Policies - Textual (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule of Certain Terms [Line Items]	'	'	'
Cash held by foreign subsidiaries	$2,800,000	'	'
Restricted cash	295,000	0	'
Accumulated Impairment Loss of Goodwill	0	'	'
Goodwill, Impairment Loss	'	0	0
Finite-Lived Intangible Asset, Useful Life	'5 years	'	'
Impairment of Intangible and Long-Lived Assets	$0	$0	$0
Minimum [Member]	'	'	'
Schedule of Certain Terms [Line Items]	'	'	'
Customer Payment Term	'30 days	'	'
Product Warranty Period	'1 year	'	'
Maximum [Member]	'	'	'
Schedule of Certain Terms [Line Items]	'	'	'
Customer Payment Term	'120 days	'	'
Product Warranty Period	'5 years	'	'

Business_Combinations_Assets_A

Business Combinations - Assets Acquired and Liabilities Assumed (Details) (USD $)	12 Months Ended								0 Months Ended	3 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Feb. 22, 2011	Feb. 22, 2011	Feb. 22, 2011	Feb. 22, 2011	Feb. 22, 2011	Nov. 02, 2012	Dec. 31, 2012
				Occam Acquisition [Member]	Occam Acquisition [Member]	Occam Acquisition [Member]	Occam Acquisition [Member]	Occam Acquisition [Member]	EFAA Acquisition [Member]	EFAA Acquisition [Member]
					Trade Names [Member]	Customer Relationships [Member]	Existing and Core Developed Technologies [Member]	Purchase Order Backlog [Member]
Business Acquisition [Line Items]	'	'	'	'	'	'	'	'	'	'
Cash and Cash Equivalents	'	'	'	$33,631	'	'	'	'	'	'
Restricted Cash	'	'	'	1,054	'	'	'	'	'	'
Accounts Receivables	'	'	'	16,854	'	'	'	'	'	'
Inventory	'	'	'	29,229	'	'	'	'	9,361	'
Other Current Asset	'	'	'	'	'	'	'	'	739	'
Prepaid Expenses and Other Assets	'	'	'	854	'	'	'	'	'	'
Property and Equipment	'	'	'	7,363	'	'	'	'	3,616	'
Total Intangible Assets	'	'	'	97,654	'	'	'	'	'	'
Goodwill	116,175	116,175	'	50,599	'	'	'	'	'	'
Current Liabilities	'	'	'	-22,414	'	'	'	'	-124	'
Deferred Tax Liability	'	'	'	'	'	'	'	'	-563	'
Deferred Revenue	'	'	'	-866	'	'	'	'	'	'
Long Term Liabilities	'	'	'	-890	'	'	'	'	'	'
Net Assets Acquired	'	'	'	'	'	'	'	'	13,029	'
Gain on bargain purchase	0	-1,029	0	'	'	'	'	'	-1,029	-1,000
Total Purchase Price	'	'	'	'	'	'	'	'	12,000	'
Total	'	'	'	213,068	'	'	'	'	'	'
Intangible Assets	'	'	'	'	'	'	'	'	'	'
Intangible Assets Acquired, Finite-Lived	'	'	'	'	2,290	51,040	25,494	2,560	'	'
In-process Technology	'	'	'	$16,270	'	'	'	'	'	'

Business_Combinations_Assets_A1

Business Combinations - Assets Acquired and Liabilities Assumed Parenthetical (Details)	12 Months Ended	0 Months Ended
	Dec. 31, 2013	Feb. 22, 2011	Feb. 22, 2011	Feb. 22, 2011	Feb. 22, 2011
		Occam Acquisition [Member]	Occam Acquisition [Member]	Occam Acquisition [Member]	Occam Acquisition [Member]
		Trade Names [Member]	Customer Relationships [Member]	Existing and Core Developed Technologies [Member]	Purchase Order Backlog [Member]
Business Acquisition [Line Items]	'	'	'	'	'
Finite-Lived Intangible Asset, Useful Life	'5 years	'6 months	'5 years	'5 years	'10 months

Business_Combinations_Occam_Fa

Business Combinations - Occam Fair Value Assumptions (Details)	0 Months Ended
	Feb. 22, 2011
Weighted average assumptions used to estimate fair value of stock options	'
Expected volatility	52.00%
Expected life	'3 years 11 months 12 days
Expected dividend yield	0.00%
Risk free interest rate	1.65%

Business_Combinations_Textual_

Business Combinations - Textual (Details) (USD $)

3 Months Ended

12 Months Ended

0 Months Ended

3 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Nov. 02, 2012

Dec. 31, 2012

Dec. 31, 2012

Feb. 22, 2011

Dec. 31, 2011

EFAA Acquisition [Member]

EFAA Acquisition [Member]

EFAA Acquisition [Member]

Occam Acquisition [Member]

Occam Acquisition [Member]

Business Acquisition [Line Items]

'

'

'

'

'

'

'

'

'

Total Consideration

'

'

'

'

$12,000,000

'

'

'

'

Gain on bargain purchase

'

0

1,029,000

0

1,029,000

1,000,000

'

'

'

Credit Received

'

'

'

'

3,300,000

'

'

'

'

Gain from utilization of inventory credit

1,700,000

1,651,000

0

0

'

'

'

'

'

Revenue of Acquiree

'

'

'

'

'

'

600,000

'

'

Cash Consideration

'

'

'

'

'

'

'

94,500,000

'

Value of Common Stock and Equity Awards Issued

'

'

'

118,628,000

'

'

'

118,600,000

'

Stock Conversion Ratio

'

'

'

'

'

'

'

0.2925

'

Cash Conversion

'

'

'

'

'

'

'

3.8337

'

Aggregate Fair Value of Stock Options and RSUs Granted

'

19,921,000

17,437,000

21,603,000

'

'

'

5,800,000

'

Acquisition-related expenses, COGS

'

0

0

19,966,000

'

'

'

'

20,000,000

[1]

Acquisition-related Expenses, Opex

'

0

[1]

1,401,000

[1]

12,927,000

[1]

'

1,400,000

[1]

1,400,000

[1]

'

12,900,000

[1]

Total value of the acquisition

'

'

'

'

'

'

'

$213,068,000

'

[1]

Includes stock-based compensation as follows (in thousands): Years Ended December 31, 2013, 2012, and 2011;Cost of revenue: $1,468, $1,433, $1,503;Research and development: $4,896, $4,227, $4,828;Sales and marketing: $5,577, $5,160, $4,500;General administrative: $7,980, $6,617, $9,538;Acquisition-related expenses: $0, $0, $1,234;Total: $19,921, $17,437, $21,603.

Goodwill_and_Intangible_Assets2

Goodwill and Intangible Assets - Schedule of Intangible Assets (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Summary of intangible assets	'	'
Gross carrying amount, intangible assets excluding goodwill	$123,704	$123,704
Accumulated amortization	-79,964	-61,403
Net, amortizable intangible assets	43,740	62,301
Core developed technology [Member]	'	'
Summary of intangible assets	'	'
Gross carrying amount, amortizable intangible assets	68,964	68,964
Accumulated amortization	-47,339	-38,986
Net, amortizable intangible assets	21,625	29,978
Customer relationships [Member]	'	'
Summary of intangible assets	'	'
Gross carrying amount, amortizable intangible assets	54,740	54,740
Accumulated amortization	-32,625	-22,417
Net, amortizable intangible assets	$22,115	$32,323

Goodwill_and_Intangible_Assets3

Goodwill and Intangible Assets - Expected Future Amortization (Details) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Summary of expected future amortization	'
2014	$18,561
2015	18,561
2016	5,805
2017	813
Total	$43,740

Goodwill_and_Intangible_Assets4

Goodwill and Intangible Assets - Textual (Details) (USD $)	12 Months Ended			3 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Mar. 31, 2012	Feb. 22, 2011
				Core Developed Technologies [Member]	Core Developed Technologies [Member]
Goodwill and Intangible Assets Disclosure [Abstract]	'	'	'	'	'
Accumulated Impairment Loss of Goodwill	$0	'	'	'	'
Amortization expense	18,561,000	17,747,000	18,121,000	'	'
Intangible Assets (Textual) [Abstract]	'	'	'	'	'
In-process technology	'	'	'	'	$16,300,000
Useful life	'	'	'	'5 years	'

Balance_Sheet_Details_Cash_and

Balance Sheet Details - Cash and Cash Equivalent (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
In Thousands, unless otherwise specified
Cash and Cash Equivalents [Abstract]	'	'	'	'
Cash	$62,905	$27,157	'	'
Money market funds	19,842	19,838	'	'
Total cash and cash equivalents	$82,747	$46,995	$38,938	$66,304

Balance_Sheet_Details_Accounts

Balance Sheet Details - Accounts Receivable (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Summary of accounts receivable, net	'	'
Accounts receivable	$44,642	$61,680
Allowance for doubtful accounts	-358	-421
Product return reserve	-764	-1,740
Accounts receivable, net	$43,520	$59,519

Balance_Sheet_Details_Inventor

Balance Sheet Details - Inventory (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Summary of inventory, net	'	'
Raw materials	$6,591	$9,377
Finished goods	44,480	33,905
Total inventory	$51,071	$43,282

Balance_Sheet_Details_Property

Balance Sheet Details - Property and Equipment, net (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Property, Plant and Equipment [Line Items]	'	'	'
Property and equipment, gross	$72,903	$77,410	'
Accumulated depreciation and amortization	-55,430	-56,327	'
Property and equipment, net	17,473	21,083	16,130
Test Equipment [Member]	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'
Property and equipment, gross	36,932	37,595	'
Computer equipment and purchased software [Member]	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'
Property and equipment, gross	27,280	31,582	'
Furniture and fixtures [Member]	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'
Property and equipment, gross	1,614	1,470	'
Leasehold improvements [Member]	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'
Property and equipment, gross	$7,077	$6,763	'

Balance_Sheet_Details_Accrued_

Balance Sheet Details - Accrued Liabilities (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Summary of accrued liabilities	'	'
Accrued compensation and related benefits	$13,127	$12,906
Accrued warranty	10,856	11,762
Accrued professional and consulting fees	1,634	1,740
Accrued excess and obsolete inventory at contract manufacturers	756	1,357
Accrued customer rebates	712	1,565
Accrued business travel expenses	540	593
Sales and use tax payable	521	929
Accrued Income Taxes, Current	368	627
Accrued Other	3,561	4,697
Total accrued liabilities	$32,075	$36,176

Balance_Sheet_Details_Deferred

Balance Sheet Details - Deferred Revenue (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Deferred Revenue Arrangement [Line Items]	'	'
Deferred Revenue, Current	$34,862	$39,315
Deferred Revenue, Noncurrent	18,431	15,782
Deferred Revenue	53,293	55,097
Product and Services	'	'
Deferred Revenue Arrangement [Line Items]	'	'
Deferred Revenue, Current	32,051	36,715
Deferred Revenue, Noncurrent	96	71
Extended Warranty	'	'
Deferred Revenue Arrangement [Line Items]	'	'
Deferred Revenue, Current	2,811	2,600
Deferred Revenue, Noncurrent	$18,335	$15,711

Balance_Sheet_Details_Accumula

Balance Sheet Details - Accumulated Other Comprehensive Income (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]	'	'	'	'
Accumulated Other Comprehensive Income (loss), Foreign Currency Translation Adjustments	$190	$132	$98	$10
Accumulated Other Comprehensive Income (loss), Unrealized Gain (loss) on Investments	0	0	0	21
Accumulated Other Comprehensive Income (Loss), Net of Tax	190	132	98	31
Foreign Currency Translation Adjustments	58	34	88	'
Unrealized loss on investments, net	0	0	-21	'
Other Comprehensive Income (Loss)	$58	$34	$67	'

Balance_Sheet_Details_Textual_

Balance Sheet Details - Textual (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Balance Sheet Related Disclosures [Abstract]	'	'	'
Depreciation and amortization	$10,181	$8,562	$7,954

Commitments_and_Contingencies_2

Commitments and Contingencies - Future Minimum Payments Under Operating Leases (Details) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]	'
2014	$3,438
2015	2,743
2016	2,252
2017	2,177
2018	1,894
Thereafter	252
Total	$12,756

Commitments_and_Contingencies_3

Commitments and Contingencies - Product Warranty Activities (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Product warranty activities [Roll Forward]	'	'	'
Balance at beginning of period	$11,762	$12,104	$3,789
Accrued warranty from the Occam acquisition	0	0	8,500
Warranty charged to cost of revenue	4,350	4,701	5,883
Utilization of warranty	-5,256	-5,043	-6,068
Balance at end of period	$10,856	$11,762	$12,104

Commitments_and_Contingencies_4

Commitments and Contingencies - Textual (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Lease Commitments	'	'	'
Future Sublease Rentals	$200,000	'	'
Unamortized Lease Incentive	500,000	'	'
Rent Expense	3,900,000	3,500,000	3,600,000
Purchase Commitments	'	'	'
Accrued Excess and Obsolete Inventory At Contract Manufacturer	756,000	1,357,000	'
Non-Cancelable Outstanding Purchase Orders	16,300,000	'	'
Litigation	'	'	'
Trading profits	500,000	'	'
Minimum [Member]	'	'	'
Accrued Warranty	'	'	'
Product Warranty Period	'1 year	'	'
Maximum [Member]	'	'	'
Accrued Warranty	'	'	'
Product Warranty Period	'5 years	'	'
Accrued Liabilities [Member]	'	'	'
Lease Commitments	'	'	'
Unamortized Lease Incentive	100,000	'	'
Other Noncurrent Liabilities [Member]	'	'	'
Lease Commitments	'	'	'
Unamortized Lease Incentive	400,000	'	'
Petaluma Lease [Member]	'	'	'
Lease Commitments	'	'	'
Lease Incentive Received	1,200,000	'	'
Amendment to Petaluma Lease [Member]	'	'	'
Lease Commitments	'	'	'
Lease Incentive Received	$400,000	'	'

Fair_Value_Measurements_Fair_V

Fair Value Measurements - Fair Value Measurements (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Summary of fair values of financial assets	'	'
Total	$19,842	$19,838
Money Market Funds [Member]	'	'
Summary of fair values of financial assets	'	'
Money market funds	19,842	19,838
Level 1 [Member]	'	'
Summary of fair values of financial assets	'	'
Total	19,842	19,838
Level 1 [Member] | Money Market Funds [Member]	'	'
Summary of fair values of financial assets	'	'
Money market funds	$19,842	$19,838

Net_Loss_per_Share_Basic_and_D

Net Loss per Share - Basic and Diluted Shares Calculation (Details) (USD $)

3 Months Ended

12 Months Ended

In Thousands, except Per Share data, unless otherwise specified

Dec. 31, 2013

Sep. 28, 2013

Jun. 29, 2013

Mar. 30, 2013

Dec. 31, 2012

Sep. 29, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Numerator:

'

'

'

'

'

'

'

'

'

'

'

Net loss

($6,453)

[1]

$544

($5,153)

($6,203)

($6,574)

[2]

($7,140)

($7,091)

($7,521)

($17,265)

($28,326)

($52,550)

Denominator:

'

'

'

'

'

'

'

'

'

'

'

Weighted-average common shares outstanding

'

'

'

'

'

'

'

'

49,419

48,180

45,546

Basic and diluted net loss per common share (Per Share)

'

'

'

'

($0.14)

[2]

($0.15)

($0.15)

($0.16)

($0.35)

($0.59)

($1.15)

Potentially dilutive shares, weighted-average

'

'

'

'

'

'

'

'

5,308

4,454

3,695

[1]

For the fourth quarter of 2013, net loss included $1.7 million of gain from utilization of inventory credit from Ericsson. See Note 2,B "Business Combinations" of these Notes to the Consolidated Financial Statements for details of the Ericsson Credit.

[2]

The Company acquired Ericsson's fiber access assets in November 2012. The quarterly financial data included the results of this acquisition only for periods subsequent to the acquisition date. See Note 2,B bBusiness Combinations" of these Notes to the Consolidated Financial Statements for details of this acquisition. For the fourth quarter of 2012, operating loss included $1.4 million of acquisition-related expenses and net loss included $1.0 million of gain from bargain purchase of Ericsson's fiber access assets.

Stockholders_Equity_Stock_Opti

Stockholders' Equity - Stock Options Activity (Details) (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
Stock Option Activity [Roll Forward]	'		'	'
Stock Options Outstanding, beginning	2,213		'	1,661
Stock options granted	573		'	'
Stock options exercised, shares	-160		'	'
Stock Options Forfeited and Expired	-66		'	'
Stock Options Outstanding, ending	2,560		'	1,661
Stock Options Vested and Expected to Vest	2,520		'	'
Weighted Average Exercise Price, Stock Options Outstanding	$12.96		$13.51	'
Weighted Average Exercise Price, Stock Options Granted	$8.57		'	'
Weighted-average Exercise Price, Stock Options Exercised	$4.66		'	'
Weighted Average Exercise Price, Stock Options Forfeited and Expired	$13.32		'	'
Weighted Average Exercise Price, Stock Options Vested and Expected to Vest	$13.02		'	'
Weighted Average Remaining Contractual Term, Stock Options Outstanding	'7 years 7 months		'	'
Weighted Average Remaining Contractual Term, Stock Options Vested and Expected to Vest	'7 years 7 months		'	'
Aggregate Intrinsic Value, Stock Options Outstanding	$2,474	[1]	'	'
Aggregate Intrinsic Value, Stock Options Vested and Expected to Vest	$2,414	[1]	'	'
[1]	Amounts represent the difference between the exercise price and the fair market value of common stock at December 31, 2013 for all in the money options outstanding.

Stockholders_Equity_Stock_Opti1

Stockholders' Equity - Stock Options By Exercise Price Range (Details) (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'
Exercise Price Lower Range Limit	$1.20
Exercise Price Upper Range Limit	$4,401.93
Number of Shares Outstanding	2,560
Weighted Average Remaining Contractual Life	'7 years 7 months
Weighted Average Exercise Price Per Share	$12.96
Number of Shares Exercisable	1,365
Weighted Average Exercise Price, Options Exercisable	$14.94
Range 1 [Member]	'
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'
Exercise Price Lower Range Limit	$1.20
Exercise Price Upper Range Limit	$6.80
Number of Shares Outstanding	453
Weighted Average Remaining Contractual Life	'7 years 4 months
Weighted Average Exercise Price Per Share	$6.31
Number of Shares Exercisable	255
Weighted Average Exercise Price, Options Exercisable	$6.12
Range 2 [Member]	'
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'
Exercise Price Lower Range Limit	$6.95
Exercise Price Upper Range Limit	$8.38
Number of Shares Outstanding	183
Weighted Average Remaining Contractual Life	'8 years 2 months
Weighted Average Exercise Price Per Share	$7.67
Number of Shares Exercisable	61
Weighted Average Exercise Price, Options Exercisable	$7.47
Range 3 [Member]	'
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'
Exercise Price Lower Range Limit	$8.41
Exercise Price Upper Range Limit	$8.41
Number of Shares Outstanding	467
Weighted Average Remaining Contractual Life	'9 years 1 month
Weighted Average Exercise Price Per Share	$8.41
Number of Shares Exercisable	95
Weighted Average Exercise Price, Options Exercisable	$8.41
Range 4 [Member]	'
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'
Exercise Price Lower Range Limit	$8.55
Exercise Price Upper Range Limit	$10.71
Number of Shares Outstanding	436
Weighted Average Remaining Contractual Life	'7 years 11 months 15 days
Weighted Average Exercise Price Per Share	$10.45
Number of Shares Exercisable	216
Weighted Average Exercise Price, Options Exercisable	$10.35
Range 5 [Member]	'
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'
Exercise Price Lower Range Limit	$10.85
Exercise Price Upper Range Limit	$18.86
Number of Shares Outstanding	508
Weighted Average Remaining Contractual Life	'7 years 2 months
Weighted Average Exercise Price Per Share	$15.58
Number of Shares Exercisable	351
Weighted Average Exercise Price, Options Exercisable	$15.74
Range 6 [Member]	'
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'
Exercise Price Lower Range Limit	$19.40
Exercise Price Upper Range Limit	$4,401.93
Number of Shares Outstanding	513
Weighted Average Remaining Contractual Life	'6 years 5 months
Weighted Average Exercise Price Per Share	$24.42
Number of Shares Exercisable	387
Weighted Average Exercise Price, Options Exercisable	$25.40

Stockholders_Equity_RSU_PRSU_a

Stockholders' Equity - RSU, PRSU, and RSA Activities (Details) (USD $)	12 Months Ended					1 Months Ended	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Jul. 31, 2011	Dec. 31, 2013	Dec. 31, 2011	Dec. 31, 2012
	Restricted Stock Units (RSUs) [Member]	Restricted Stock Units (RSUs) [Member]	Restricted Stock Units (RSUs) [Member]	Performance Restricted Stock Units [Member]	Performance Restricted Stock Units [Member]	Restricted Stocks [Member]	Restricted Stocks [Member]	Restricted Stocks [Member]	Restricted Stocks [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'	'	'	'	'
Weighted Average Grant Date Fair Value Per Share, Outstanding	$11.04	$11.67	'	$12.81	$14.78	'	$21.67	'	$21.67
Weighted Average Grant Date Fair Value Per Share, Granted	$9.20	$6.55	$21.33	$11.24	$14.81	'	$0	$21.67	'
Weighted Average Grant Date Fair Value Per Share, Vested	$11.07	'	'	$0	'	'	$21.67	'	'
Weighted Average Grant Date Fair Value Per Share, Canceled	$9.51	'	'	$0	'	'	$21.67	'	'
RSU, PRSU, and RSA Activities Roll Forward	'	'	'	'	'	'	'	'	'
Outstanding, Beginning of Year	1,762,000	1,775,000	'	183,000	0	'	299,000	'	'
Shares Granted	705,000	'	'	230,000	'	423,000	0	'	'
Shares Vested	-822,000	'	'	0	'	'	-95,000	'	'
Shares Canceled	-139,000	'	'	0	'	'	-15,000	'	'
Outstanding, End of Year	1,506,000	1,762,000	1,775,000	413,000	183,000	'	189,000	'	'

Stockholders_Equity_Fair_Value

Stockholders' Equity - Fair Value of Awards Granted (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Weighted-average Grant Date Fair Value Per Share, Stock Options	$4.89	$4.68	$9.77
Restricted Stock Units (RSUs) [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Weighted Average Grant Date Fair Value Per Share	$9.20	$6.55	$21.33
Performance Restricted Stock Units [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Weighted Average Grant Date Fair Value Per Share	$11.24	$14.81	'
Restricted Stocks [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Weighted Average Grant Date Fair Value Per Share	$0	'	$21.67
Employee Stock Purchase Plan [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Weighted Average Grant Date Fair Value Per Share	$2.94	$2.34	$3.48

Stockholders_Equity_Assumption

Stockholders' Equity - Assumptions (Details)	0 Months Ended	3 Months Ended	12 Months Ended
	Feb. 22, 2011	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
		Stock Options [Member]	Stock Options [Member]	Stock Options [Member]	Stock Options [Member]	Employee Stock Purchase Plan [Member]	Employee Stock Purchase Plan [Member]	Employee Stock Purchase Plan [Member]
Weighted average assumptions used to estimate fair value of stock options	'	'	'	'	'	'	'	'
Expected volatility	52.00%	66.00%	62.00%	56.00%	52.00%	50.00%	63.00%	52.00%
Expected life	'3 years 11 months 12 days	'	'6 years 19 days	'6 years 3 months	'6 years 3 months	'6 months	'6 months	'6 months
Expected dividend yield	0.00%	'	0.00%	0.00%	0.00%	0.00%	0.00%	0.00%
Risk free interest rate	1.65%	'	1.14%	1.06%	2.11%	0.09%	0.13%	0.66%

Stockholders_Equity_Unrecogniz

Stockholders' Equity - Unrecognized Stock-based Compensation Expenses (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013
Stock Options [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Unrecognized stock-based compensation expense	$6,391
Weighted-average amortization period	'2 years 2 months 17 days
Restricted Stock Units (RSUs) [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Unrecognized stock-based compensation expense	10,861
Weighted-average amortization period	'2 years 3 months 9 days
Performance Restricted Stock Units [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Unrecognized stock-based compensation expense	1,801
Weighted-average amortization period	'1 year 4 months 2 days
Restricted Stocks [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Unrecognized stock-based compensation expense	2,392
Weighted-average amortization period	'1 year 6 months 3 days
Employee Stock Purchase Plan [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Unrecognized stock-based compensation expense	$662
Weighted-average amortization period	'5 months

Stockholders_Equity_Warrants_O

Stockholders' Equity - Warrants Outstanding (Details)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013
Class of Warrant or Right [Line Items]	'
Number of Warrants Outstanding	23
Expiration Date 1 [Member]	'
Class of Warrant or Right [Line Items]	'
Expiration Date, Warrants	16-Aug-14
Exercise Price Per Share, Warrants	10.26
Number of Warrants Outstanding	8
Expiration Date 2 [Member]	'
Class of Warrant or Right [Line Items]	'
Expiration Date, Warrants	4-Sep-17
Exercise Price Per Share, Warrants	19.56
Number of Warrants Outstanding	15

Stockholders_Equity_Shares_Res

Stockholders' Equity - Shares Reserved For Future Issuance (Details)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Mar. 02, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Stock Options Outstanding	2,560,000	2,213,000	1,661,000	'
Shares Reserved For Future Issuance	10,728,000	11,400,000	8,546,000	'
Common Stock Warrants	23,000	23,000	23,000	'
Restricted Stock Units (RSUs) [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Outstanding Awards Other Than Option	1,506,000	1,762,000	1,775,000	'
Performance Restricted Stock Units [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Outstanding Awards Other Than Option	413,000	183,000	0	'
2010 Plan [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Shares Available for Future Grant	3,652,000	3,959,000	4,508,000	'
Shares Reserved For Future Issuance	'	'	'	4,666,666
Employee Stock Purchase Plan [Member]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'
Shares Reserved For Future Issuance	2,574,000	3,260,000	579,000	'

Stockholders_Equity_Textual_De

Stockholders' Equity - Textual (Details) (USD $)

0 Months Ended

12 Months Ended

0 Months Ended

3 Months Ended

12 Months Ended

9 Months Ended

12 Months Ended

0 Months Ended

1 Months Ended

12 Months Ended

36 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

Feb. 22, 2011

Mar. 26, 2010

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Mar. 26, 2010

Apr. 08, 2010

Mar. 26, 2010

Feb. 22, 2011

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Sep. 29, 2012

Sep. 29, 2012

Dec. 31, 2013

Feb. 22, 2011

Jul. 31, 2011

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2013

Mar. 02, 2010

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Sep. 23, 2009

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

IPO [Member]

Underwriter Option [Member]

Underwriter Option [Member]

Occam Acquisition [Member]

Stock Options [Member]

Stock Options [Member]

Stock Options [Member]

Stock Options [Member]

Stock Options [Member]

Stock Options [Member]

Restricted Stock Units (RSUs) [Member]

Restricted Stock Units (RSUs) [Member]

Restricted Stocks [Member]

Restricted Stocks [Member]

Performance Restricted Stock Units [Member]

Performance Restricted Stock Units [Member]

Performance Restricted Stock Units [Member]

Performance Restricted Stock Units [Member]

Performance Restricted Stock Units [Member]

Prior Plans [Member]

Prior Plans [Member]

2010 Plan [Member]

2010 Plan [Member]

2010 Plan [Member]

Employee Stock Purchase Plan [Member]

Employee Stock Purchase Plan [Member]

Employee Stock Purchase Plan [Member]

Stock Option Exchange Program [Member]

Incentive Stock Option [Member]

Non-qualified Stock Option [Member]

Non-qualified Stock Option [Member]

Minimum [Member]

Maximum [Member]

Occam Acquisition [Member]

Minimum [Member]

Minimum [Member]

Maximum [Member]

Maximum [Member]

Prior Plans [Member]

2000 Plan [Member]

2002 Plan [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Common Stock, Shares Authorized

'

'

100,000,000

100,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Preferred stock, shares authorized

'

'

5,000,000

5,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Common Stock Issuance Date

'

'

'

'

'

26-Mar-10

8-Apr-10

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Common Stock Sold in Initial Public Offering, shares

'

'

'

'

'

4,166,666

'

949,339

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

IPO Price Per Share

'

$13

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Proceeds from Issuance of Common Stock

'

'

'

'

'

$54,200,000

'

$12,300,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock Issuance Costs

'

'

'

'

'

4,600,000

'

800,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Underwriter's Fee

'

3,800,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock Issued for Occam Acquisition, shares

6,400,000

'

'

'

6,359,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock Issued For Occam Acquisition

117,200,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Dividends Declared Or Paid, Per Share

'

'

$0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Document Period End Date

'

'

'

31-Dec-13

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Preferred Stock, Shares Issued

'

'

0

0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Minimum Exercise Price Of Stock Option Percent

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

100.00%

'

'

'

'

'

'

100.00%

85.00%

100.00%

Vesting Period

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'4 years

'

'4 years

'

'

'

'

'

'

'

'

'

Contractual Term, Stock Options

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'10 years

'10 years

'

'

'

'

'

'

'

'

'

Maximum Shares Allowed To Be Issued

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

17,150,494

'

'

'

'

'

'

'

'

'

Automatic Annual Increase of Reserved Shares

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,999,998

'

'

'

'

'

'

'

'

Vesting Term

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'vest 25% per year for 4 years from the grant date

'

'

'

'

'

'

'

'

'vestB 25%B on the first anniversary of the vesting commencement date and on a monthly basis thereafter for a period of an additional three years

'

'

'

'

'

'

'

'

'

Common Stock, Conversion Basis

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'Each RSU granted under the 2010 Plan represents a right to receive one share of the Companybs common stock (subject to adjustment for certain specified changes in the capital structure of the Company) upon the completion of a specific period of continued service.

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Performance period, PRSU

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'2 years

'

'3 years

'

'

'

'

'

'

'

'

'

'

'

'

'

Target Performance Rate, PRSU

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

0.00%

'

200.00%

'

'

'

'

'

'

'

'

'

'

'

'

Stock Options Forfeited and Expired

'

'

66,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

3,400,000

'

'

'

Total Intrinsic Value For Stock Options Exercised

'

'

1,000,000

600,000

2,700,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Proceeds from Stock Options Exercised

'

'

700,000

200,000

800,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Fair value of accelerated stock awards

'

'

600,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Fair value recognized for accelerated stock awards

'

'

500,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

ESPP, maximum employee payroll deduction percentage

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

15.00%

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Maximum Number of Shares Per Employee

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2,000

'

'

'

'

'

'

ESPP, discounted purchase price percentage

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

85.00%

'

'

'

'

'

'

Shares authorized

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

4,300,000

'

'

'

'

'

'

Shares issued in connection with Employee Stock Purchase Plan

'

'

685,781

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Shares Reserved For Future Issuance

'

'

10,728,000

11,400,000

8,546,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

4,666,666

2,574,000

3,260,000

579,000

'

'

'

'

Stock based compensation

'

'

19,921,000

17,437,000

21,603,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Percent of Historical Volatility

'

'

50.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Percent of Implied Volatility

'

'

50.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Expected volatility

52.00%

'

'

'

'

'

'

'

'

66.00%

62.00%

56.00%

52.00%

55.00%

56.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock options granted, shares

'

'

573,000

'

'

'

'

'

536,190

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Awards granted, shares

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

705,000

42,654

423,000

0

230,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Aggregate Fair Value of Stock Options and RSUs Granted

'

'

19,921,000

17,437,000

21,603,000

'

'

'

5,800,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Consideration Transferred, Fair Value of Stock Options and RSUs Assumed

'

'

'

'

'

'

'

'

1,400,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Post Combination Expense

'

'

'

'

'

'

'

'

$4,500,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Employee_Benefit_Plan_Textual_

Employee Benefit Plan - Textual (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]	'	'	'
Company matching contributions, 401(K) Plan	$1.50	$1.40	$1.30

Credit_Facility_Textual_Detail

Credit Facility - Textual (Details) (USD $)	0 Months Ended	12 Months Ended
	Jul. 29, 2013	Dec. 31, 2013	Sep. 28, 2013	Dec. 31, 2012
	extention
Line of Credit Facility [Line Items]	'	'	'	'
Revolving credit facility, maximum capacity	$50,000,000	'	'	'
Revolving credit facility, maturity date	29-Jul-16	'	'	'
Restricted cash	'	295,000	'	0
Number of one-year period extensions	2	'	'	'
Line of Credit Facility, Frequency of Payment and Payment Terms	'Interest on the revolving facility is due quarterly, and any outstanding interest and principal is due on the maturity date of the revolving facility.	'	'	'
Commitment fee percentage	'	0.25%	'	'
Revolving credit facility, available for borrowing	'	50,000,000	'	'
Payments of Debt Issuance Costs	'	316,000	'	'
Unamortized Debt Issuance Expense	'	'	300,000	'
Prior Credit Facility [Member]	'	'	'	'
Line of Credit Facility [Line Items]	'	'	'	'
Revolving credit facility, maximum capacity	'	30,000,000	'	'
Revolving credit facility, maturity date	'	30-Jun-13	'	'
Letter of Credit [Member]	'	'	'	'
Line of Credit Facility [Line Items]	'	'	'	'
Revolving credit facility, maximum capacity	20,000,000	'	'	'
Swingline Facility Member [Member]	'	'	'	'
Line of Credit Facility [Line Items]	'	'	'	'
Revolving credit facility, maximum capacity	10,000,000	'	'	'
Long-term Debt [Member]	'	'	'	'
Line of Credit Facility [Line Items]	'	'	'	'
Revolving credit facility, maximum capacity	$25,000,000	'	'	'
Base Rate [Member] | Minimum [Member]	'	'	'	'
Line of Credit Facility [Line Items]	'	'	'	'
Debt Instrument, Basis Spread on Variable Rate	0.75%	'	'	'
Base Rate [Member] | Maximum [Member]	'	'	'	'
Line of Credit Facility [Line Items]	'	'	'	'
Debt Instrument, Basis Spread on Variable Rate	1.25%	'	'	'
LIBOR [Member] | Minimum [Member]	'	'	'	'
Line of Credit Facility [Line Items]	'	'	'	'
Debt Instrument, Basis Spread on Variable Rate	2.00%	'	'	'
LIBOR [Member] | Maximum [Member]	'	'	'	'
Line of Credit Facility [Line Items]	'	'	'	'
Debt Instrument, Basis Spread on Variable Rate	2.50%	'	'	'

Income_Taxes_Components_of_Inc

Income Taxes - Components of Income Tax Provision (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Provision For Income Taxes [Line Items]	'	'	'
Federal current income tax	($274)	$152	$0
State current income tax	41	73	114
Foreign current income tax	315	440	228
Federal deferred income tax (benefit)	0	-474	0
State deferred income tax (benefit)	0	-89	0
Foreign deferred income tax (benefit)	-96	56	-118
Provision for (benefit from) income taxes	($14)	$158	$224

Income_Taxes_Income_Tax_Rate_R

Income Taxes - Income Tax Rate Reconciliation (Details)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Rate Reconcilation [Line Items]	'	'	'
Federal statutory rate	34.00%	34.00%	34.00%
State statutory rate	3.40%	5.20%	5.20%
Foreign operations	1.40%	0.10%	0.20%
Release of FIN 48 liability and interest	0.70%	0.00%	0.00%
R&D tax credits	13.10%	2.50%	2.10%
Other permanent items	-4.50%	0.10%	-1.60%
2012 tax true-up	1.00%	0.00%	0.00%
Valuation allowance	-49.00%	-45.70%	-38.80%
Effective Tax Rate	0.10%	-0.60%	-0.40%
Release of valuation allowance related to EFAA acquisition [Member]	'	'	'
Income Tax Rate Reconcilation [Line Items]	'	'	'
Other adjustments	0.00%	2.00%	0.00%
Acquisition-related Costs [Member]	'	'	'
Income Tax Rate Reconcilation [Line Items]	'	'	'
Other adjustments	0.00%	1.20%	-1.50%

Income_Taxes_Components_of_Def

Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Deferred Tax Assets, Net [Abstract]	'	'
Net Operating Loss Carryforwards	$168,431	$180,005
Tax Credit Carryforward, Amount	22,507	20,154
Depreciation and Amortization	2,996	2,858
Accruals and Reserves	11,479	11,353
Deferred Revenue	12,037	13,367
Stock-based Compensation	5,570	3,592
Other	450	294
Gross Deferred Tax Assets	223,470	231,623
Valuation Allowance	-207,315	-207,441
Net Deferred Tax Assets	16,155	24,182
Deferred Tax Liabilities, Gross [Abstract]	'	'
Intangible Assets	-15,988	-24,120
Deferred Tax Assets, Net	$167	$62

Income_Taxes_Unrecognized_Tax_

Income Taxes - Unrecognized Tax Benefits Activity (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Unrecognized Tax Benefits Roll Forward	'	'
Beginning Balance	$13,238	$12,543
Additions For Tax Positions Related To Prior Year	317	228
Reductions For Tax Positions Related To Prior Year	-48	-37
Additions For Tax Positions Related To Current Year	990	504
Reductions from a lapse of applicable statute of limitations	-115	0
Ending Balance	$14,382	$13,238

Income_Taxes_Textual_Details

Income Taxes - Textual (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Taxes [Line Items]	'	'	'
Provision for (benefit from) income taxes	($14,000)	$158,000	$224,000
Increase (decrease) In Valuation Allowance	-100,000	5,400,000	'
Excess tax benefits of stock option deductions included in valuation allowance	100,000	100,000	'
Research and Development Credits	22,507,000	20,154,000	'
Unrecognized tax benefits that would impact effective tax rate uncertain income taxes	0	100,000	'
Accrued interest or penalties for uncertain income tax	0	'	'
US Federal [Member]	'	'	'
Income Taxes [Line Items]	'	'	'
Operating Loss Carryforwards	550,100,000	'	'
Deduction related to excess tax benefits from stock options which are not included in net operating loss carryforward	37,200,000	36,300,000	'
Research and Development Credits	18,500,000	'	'
State	'	'	'
Income Taxes [Line Items]	'	'	'
Operating Loss Carryforwards	174,200,000	'	'
Deduction related to excess tax benefits from stock options which are not included in net operating loss carryforward	34,000,000	33,300,000	'
California State [Member]	'	'	'
Income Taxes [Line Items]	'	'	'
Research and Development Credits	22,000,000	'	'
Other State [Member]	'	'	'
Income Taxes [Line Items]	'	'	'
Research and Development Credits	1,800,000	'	'
Occam Acquisition [Member]	'	'	'
Income Taxes [Line Items]	'	'	'
Operating Loss Carryforwards	$5,300,000	'	'

Segment_Information_Revenue_by

Segment Information - Revenue by Geographic Region (Details) (USD $)

3 Months Ended

12 Months Ended

In Thousands, unless otherwise specified

Dec. 31, 2013

Sep. 28, 2013

Jun. 29, 2013

Mar. 30, 2013

Dec. 31, 2012

Sep. 29, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Revenues from External Customers and Long-Lived Assets [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Revenue

$94,003

[1]

$103,628

$94,439

$90,548

$91,424

[2]

$81,301

$78,928

$78,565

$382,618

$330,218

$344,669

United States, Country [Member]

'

'

'

'

'

'

'

'

'

'

'

Revenues from External Customers and Long-Lived Assets [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Revenue

'

'

'

'

'

'

'

'

333,403

306,003

323,070

Canada [Member]

'

'

'

'

'

'

'

'

'

'

'

Revenues from External Customers and Long-Lived Assets [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Revenue

'

'

'

'

'

'

'

'

10,231

10,894

6,691

Europe [Member]

'

'

'

'

'

'

'

'

'

'

'

Revenues from External Customers and Long-Lived Assets [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Revenue

'

'

'

'

'

'

'

'

17,397

268

211

Caribbean

'

'

'

'

'

'

'

'

'

'

'

Revenues from External Customers and Long-Lived Assets [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Revenue

'

'

'

'

'

'

'

'

17,466

9,343

12,837

Other [Member]

'

'

'

'

'

'

'

'

'

'

'

Revenues from External Customers and Long-Lived Assets [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Revenue

'

'

'

'

'

'

'

'

$4,121

$3,710

$1,860

[1]

For the fourth quarter of 2013, net loss included $1.7 million of gain from utilization of inventory credit from Ericsson. See Note 2,B "Business Combinations" of these Notes to the Consolidated Financial Statements for details of the Ericsson Credit.

[2]

The Company acquired Ericsson's fiber access assets in November 2012. The quarterly financial data included the results of this acquisition only for periods subsequent to the acquisition date. See Note 2,B bBusiness Combinations" of these Notes to the Consolidated Financial Statements for details of this acquisition. For the fourth quarter of 2012, operating loss included $1.4 million of acquisition-related expenses and net loss included $1.0 million of gain from bargain purchase of Ericsson's fiber access assets.

Segment_Information_Property_a

Segment Information - Property and Equipment by Geographic Region (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Property, Plant and Equipment, Net	$17,473	$21,083	$16,130
United States, Country [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Property, Plant and Equipment, Net	14,969	18,390	14,339
China [Member]	'	'	'
Revenues from External Customers and Long-Lived Assets [Line Items]	'	'	'
Property, Plant and Equipment, Net	$2,504	$2,693	$1,791

Quarterly_Financial_Data_Unaud2

Quarterly Financial Data - Unaudited Quarterly Financial Data - Unaudited (Details) (USD $)	3 Months Ended										12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013		Sep. 28, 2013	Jun. 29, 2013	Mar. 30, 2013	Dec. 31, 2012		Sep. 29, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Quarterly Financial Information Disclosure [Abstract]	'		'	'	'	'		'	'	'	'	'	'
Revenue	$94,003	[1]	$103,628	$94,439	$90,548	$91,424	[2]	$81,301	$78,928	$78,565	$382,618	$330,218	$344,669
Gross profit	40,047	[1]	47,407	42,505	41,115	37,030	[2]	33,506	33,221	33,819	171,074	137,576	119,453
Operating loss	-8,056	[1]	-12	-4,845	-5,540	-7,748	[2]	-7,077	-6,830	-7,369	-18,453	-29,024	-52,321
Net income (loss)	($6,453)	[1]	$544	($5,153)	($6,203)	($6,574)	[2]	($7,140)	($7,091)	($7,521)	($17,265)	($28,326)	($52,550)
Net income (loss) per common share, basic (Per Share)	($0.13)	[1]	$0.01	($0.10)	($0.13)	'		'	'	'	'	'	'
Net income (loss) per common share, diluted (Per Share)	($0.13)	[1]	$0.01	($0.10)	($0.13)	'		'	'	'	'	'	'
Basic and diluted net loss per common share (Per Share)	'		'	'	'	($0.14)	[2]	($0.15)	($0.15)	($0.16)	($0.35)	($0.59)	($1.15)
[1]	For the fourth quarter of 2013, net loss included $1.7 million of gain from utilization of inventory credit from Ericsson. See Note 2,B "Business Combinations" of these Notes to the Consolidated Financial Statements for details of the Ericsson Credit.
[2]	The Company acquired Ericsson's fiber access assets in November 2012. The quarterly financial data included the results of this acquisition only for periods subsequent to the acquisition date. See Note 2,B bBusiness Combinations" of these Notes to the Consolidated Financial Statements for details of this acquisition. For the fourth quarter of 2012, operating loss included $1.4 million of acquisition-related expenses and net loss included $1.0 million of gain from bargain purchase of Ericsson's fiber access assets.

Quarterly_Financial_Data_Unaud3

Quarterly Financial Data - Unaudited Quarterly Financial Data - Unaudited (Parenthetical) (Details) (USD $)

3 Months Ended

12 Months Ended

0 Months Ended

3 Months Ended

12 Months Ended

In Thousands, unless otherwise specified

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Nov. 02, 2012

Dec. 31, 2012

Dec. 31, 2012

EFAA Acquisition [Member]

EFAA Acquisition [Member]

EFAA Acquisition [Member]

Business Acquisition [Line Items]

'

'

'

'

'

'

'

Gain from utilization of inventory credit

$1,700

$1,651

$0

$0

'

'

'

Acquisition-related Expenses, Opex

'

0

[1]

1,401

[1]

12,927

[1]

'

1,400

[1]

1,400

[1]

Gain on bargain purchase

'

$0

$1,029

$0

$1,029

$1,000

'

[1]

Includes stock-based compensation as follows (in thousands): Years Ended December 31, 2013, 2012, and 2011;Cost of revenue: $1,468, $1,433, $1,503;Research and development: $4,896, $4,227, $4,828;Sales and marketing: $5,577, $5,160, $4,500;General administrative: $7,980, $6,617, $9,538;Acquisition-related expenses: $0, $0, $1,234;Total: $19,921, $17,437, $21,603.

Schedule_II_Valuation_and_Qual1

Schedule II. Valuation and Qualifying Accounts - Valuation and Qualitying Accounts (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Allowance for Doubtful Accounts [Member]	'	'	'
Movement in Valuation Allowances and Reserves [Roll Forward]	'	'	'
Balance At Beginning of Year	$421	$402	$617
Additions Charged to Cost or Expense or Revenue	-13	112	130
Deductions and Write Offs	-50	-93	-345
Balance At End of Year	358	421	402
Product Return Reserve [Member]	'	'	'
Movement in Valuation Allowances and Reserves [Roll Forward]	'	'	'
Balance At Beginning of Year	1,740	835	551
Additions Charged to Cost or Expense or Revenue	3,535	5,474	4,996
Deductions and Write Offs	-4,511	-4,569	-4,712
Balance At End of Year	$764	$1,740	$835