Ixia (XXIA) 10-K 23 Jun 14 2013 FY Annual report Financial data

Document_And_Entity_Informatio

Document And Entity Information (USD $)	12 Months Ended
	Dec. 31, 2013	Jun. 16, 2014	Jun. 28, 2013
Document and Entity Information [Abstract]	'	'	'
Entity Registrant Name	'Ixia	'	'
Document Type	'10-K	'	'
Current Fiscal Year End Date	'--12-31	'	'
Entity Common Stock, Shares Outstanding	'	76,981,053	'
Entity Public Float	'	'	$1,056,492,377
Amendment Flag	'false	'	'
Entity Central Index Key	'0001120295	'	'
Entity Current Reporting Status	'No	'	'
Entity Voluntary Filers	'No	'	'
Entity Filer Category	'Large Accelerated Filer	'	'
Entity Well-known Seasoned Issuer	'No	'	'
Document Period End Date	31-Dec-13	'	'
Document Fiscal Year Focus	'2013	'	'
Document Fiscal Period Focus	'FY	'	'

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$34,189	$47,508
Short-term investments in marketable securities	51,507	126,851
Accounts receivable, net	109,590	103,523
Inventories	47,136	37,220
Prepaid expenses and other current assets	42,096	42,942
Total current assets	284,518	358,044
Investments in marketable securities	'	3,119
Property, plant and equipment, net	35,932	28,763
Intangible assets, net	189,949	157,003
Goodwill	371,832	260,457
Other assets	12,233	11,863
Total assets	894,464	819,249
Current liabilities:	'	'
Accounts payable	19,011	12,114
Accrued expenses and other	53,748	52,525
Deferred revenues	89,217	66,096
Total current liabilities	161,976	130,735
Deferred revenues	15,106	8,695
Other liabilities	18,270	32,321
Convertible senior notes	200,000	200,000
Total liabilities	395,352	371,751
Commitments and contingencies (Note 10)	'	'
Shareholders’ equity:	'	'
Preferred stock, without par value; 1,000 shares authorized and none outstanding	'	'
Common stock, without par value; 200,000 shares authorized at December 31, 2013 and 2012; 76,849 and 74,126 shares issued and outstanding as of December 31, 2013 and 2012, respectively	178,347	158,933
Additional paid-in capital	191,976	168,980
Retained earnings	129,166	117,296
Accumulated other comprehensive income (loss)	-377	2,289
Total shareholders’ equity	499,112	447,498
Total liabilities and shareholders’ equity	$894,464	$819,249

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parentheticals) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Preferred stock, without par value (in Dollars per share)	'	'
Preferred stock, shares authorized	1,000	1,000
Preferred stock, shares outstanding	0	0
Common stock, without par value (in Dollars per share)	'	'
Common stock, shares authorized	200,000	200,000
Common stock, shares issued	76,849	74,126
Common stock, shares outstanding	76,849	74,126

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	12 Months Ended
Share data in Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Revenues:	'		'		'
Products	$352,712,000		$330,315,000		$249,423,000
Services	114,544,000		83,119,000		61,947,000
Total revenues	467,256,000		413,434,000		311,370,000
Costs and operating expenses: (1)	'		'		'
Cost of revenues - products (2)	89,136,000	[1]	71,668,000	[1]	56,801,000	[1]
Cost of revenues - services	13,867,000		10,493,000		6,520,000
Research and development	117,502,000		98,169,000		75,101,000
Sales and marketing	137,724,000		117,214,000		87,011,000
General and administrative	47,158,000		45,607,000		33,648,000
Amortization of intangible assets	40,805,000		30,018,000		15,980,000
Acquisition and other related	6,920,000		11,861,000		1,100,000
Restructuring	1,840,000		4,077,000		'
Total costs and operating expenses	454,952,000		389,107,000		276,161,000
Income from operations	12,304,000		24,327,000		35,209,000
Interest income and other, net	6,269,000		2,255,000		2,059,000
Interest expense	-7,771,000		-7,215,000		-7,200,000
Income before income taxes	10,802,000		19,367,000		30,068,000
Income tax (benefit) expense	-1,068,000		-26,093,000		3,355,000
Net income	11,870,000		45,460,000		26,713,000
Earnings per share:	'		'		'
Basic (in Dollars per share)	$0.16		$0.63		$0.39
Diluted (in Dollars per share)	$0.15		$0.59		$0.37
Weighted average number of common and common equivalent shares outstanding:	'		'		'
Basic (in Shares)	75,757		72,183		69,231
Diluted (in Shares)	77,513		84,505		71,664
Cost of Revenues - Products [Member]	'		'		'
Costs and operating expenses: (1)	'		'		'
Amortization of intangible assets	$26,000,000		$20,300,000		$10,800,000
[1]	Cost of revenues - products excludes amortization of intangible assets, related to purchased technology of $26.0 million, $20.3 million and $10.8 million for the years ended December 31, 2013, 2012 and 2011, respectively, which is included in Amortization of intangible assets.

Consolidated_Statements_of_Ope1

Consolidated Statements of Operations (Parentheticals) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Amortization of intangible assets	$40,805	$30,018	$15,980
Cost of Revenues - Products [Member]	'	'	'
Stock-based compensation	550	423	402
Amortization of intangible assets	26,000	20,300	10,800
Cost of Revenues - Services [Member]	'	'	'
Stock-based compensation	209	162	153
Research and Development Expense [Member]	'	'	'
Stock-based compensation	8,065	6,242	4,286
Selling and Marketing Expense [Member]	'	'	'
Stock-based compensation	7,367	5,352	3,296
General and Administrative Expense [Member]	'	'	'
Stock-based compensation	$4,571	$7,462	$4,454

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
Net income	$11,870		$45,460	$26,713
Other comprehensive income (loss)	'		'	'
Change in unrealized gains and losses on investments, net of tax	-2,028		586	-456
Cumulative translation adjustment	-638	[1]	-527	232
Total other comprehensive (loss) income, net of tax	-2,666		59	-224
Comprehensive income	$9,204		$45,519	$26,489
[1]	All amounts are net-of-tax. Amounts in parentheses indicate reductions.

Consolidated_Statements_of_Sha

Consolidated Statements of Shareholders' Equity (USD $)	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
In Thousands
Balance at Dec. 31, 2010	$115,590	$133,249	$45,123	$2,454	$296,416
Balance (in Shares) at Dec. 31, 2010	67,613	'	'	'	'
Net income	'	'	26,713	'	26,713
Change in unrealized gains and losses on investments, net of tax	'	'	'	-456	-456
Cumulative translation adjustment	'	'	'	232	232
Shares issued pursuant to stock incentive plans and employee stock purchase plan options	16,740	'	'	'	16,740
Shares issued pursuant to stock incentive plans and employee stock purchase plan options (in Shares)	2,627	'	'	'	'
Stock-based compensation	'	12,591	'	'	12,591
Balance at Dec. 31, 2011	132,330	145,840	71,836	2,230	352,236
Balance (in Shares) at Dec. 31, 2011	70,240	'	'	'	'
Net income	'	'	45,460	'	45,460
Change in unrealized gains and losses on investments, net of tax	'	'	'	586	586
Cumulative translation adjustment	'	'	'	-527	-527
Shares issued pursuant to stock incentive plans and employee stock purchase plan options	26,603	'	'	'	26,603
Shares issued pursuant to stock incentive plans and employee stock purchase plan options (in Shares)	3,886	'	'	'	'
Stock-based compensation	'	19,641	'	'	19,641
Stock award tax benefit	'	3,499	'	'	3,499
Balance at Dec. 31, 2012	158,933	168,980	117,296	2,289	447,498
Balance (in Shares) at Dec. 31, 2012	74,126	'	'	'	74,126
Net income	'	'	11,870	'	11,870
Change in unrealized gains and losses on investments, net of tax	'	'	'	-2,028	-2,028
Cumulative translation adjustment	'	'	'	-638	-638	[1]
Shares issued pursuant to stock incentive plans and employee stock purchase plan options	19,414	'	'	'	19,414
Shares issued pursuant to stock incentive plans and employee stock purchase plan options (in Shares)	2,723	'	'	'	'
Stock-based compensation	'	20,762	'	'	20,762
Stock award tax benefit	'	2,234	'	'	2,234
Balance at Dec. 31, 2013	$178,347	$191,976	$129,166	($377)	$499,112
Balance (in Shares) at Dec. 31, 2013	76,849	'	'	'	76,849
[1]	All amounts are net-of-tax. Amounts in parentheses indicate reductions.

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash flows from operating activities:	'	'	'
Net income	$11,870,000	$45,460,000	$26,713,000
Adjustments to reconcile net income to net cash provided operating activities:	'	'	'
Depreciation	16,061,000	16,034,000	13,354,000
Amortization of intangible assets	40,805,000	30,018,000	15,980,000
Realized gain on sale of available-for-sale securities	-4,469,000	-1,300,000	-437,000
Stock-based compensation	20,762,000	19,641,000	12,591,000
Deferred income taxes	-6,664,000	-42,363,000	-918,000
Excess tax benefits from stock-based compensation	-2,477,000	-3,025,000	'
Changes in operating assets and liabilities, net of effect of acquisitions:	'	'	'
Accounts receivable, net	3,416,000	-21,771,000	4,141,000
Inventories	-11,036,000	-2,445,000	2,046,000
Prepaid expenses and other current assets	-6,773,000	1,483,000	34,000
Other assets	3,154,000	54,000	786,000
Accounts payable	3,195,000	5,521,000	-5,085,000
Accrued expenses and other	-7,442,000	11,135,000	-8,834,000
Deferred revenues	24,362,000	18,389,000	866,000
Other liabilities	1,736,000	2,183,000	-343,000
Net cash provided by operating activities	86,500,000	80,314,000	61,331,000
Cash flows from investing activities:	'	'	'
Purchases of property and equipment	-12,131,000	-17,726,000	-15,268,000
Purchases of available-for-sale securities	-191,973,000	-168,623,000	-389,398,000
Proceeds from available-for-sale securities	271,585,000	381,904,000	309,495,000
Purchases of other intangible assets	-893,000	-843,000	-430,000
Payments in connection with acquisitions, net of cash acquired	-188,298,000	-298,928,000	-15,823,000
Net cash used in investing activities	-121,710,000	-104,216,000	-111,424,000
Cash flows from financing activities:	'	'	'
Debt issuance costs	'	-947,000	'
Proceeds from exercise of stock options and employee stock purchase plan options	19,414,000	26,603,000	16,740,000
Excess tax benefits from stock-based compensation	2,477,000	3,025,000	'
Net cash provided by financing activities	21,891,000	28,681,000	16,740,000
Net (decrease) increase in cash and cash equivalents	-13,319,000	4,779,000	-33,353,000
Cash and cash equivalents at beginning of year	47,508,000	42,729,000	76,082,000
Cash and cash equivalents at end of year	34,189,000	47,508,000	42,729,000
Cash paid during the period for:	'	'	'
Interest	6,000,000	6,000,000	6,133,000
Income taxes	10,334,000	7,596,000	4,887,000
Supplemental disclosure of non-cash investing activities:	'	'	'
Purchased and unpaid property and equipment	1,104,000	'	'
Transfers of inventory to property and equipment	$7,663,000	'	'

Note_1_Description_of_Business

Note 1 - Description of Business, Basis of Presentation, Significant Accounting Policies and Recent Accounting Pronouncements	12 Months Ended
	Dec. 31, 2013
Disclosure Text Block [Abstract]	'
Business Description and Accounting Policies [Text Block]	'
		1	Description of Business, Basis of Presentation, Significant Accounting Policies and Recent Accounting Pronouncements
	Description of Business
	Ixia was incorporated on May 27, 1997 as a California corporation. We are a leading provider of converged Internet Protocol (IP) network test and network visibility solutions. Equipment manufacturers, service providers, enterprises, and government agencies use our solutions to design, verify, and monitor a broad range of Ethernet, Wi-Fi, 3G and 4G/LTE equipment and networks. Our product solutions consist of our hardware platforms, such as our chassis, interface cards and appliances, software application tools, and services, including our warranty and maintenance offerings and professional services.
	The Company is headquartered in Calabasas, California with operations across the U.S. and the rest of the world.  Our revenues are principally derived from shipments within the U.S. and to the EMEA and Asia Pacific regions.
	Basis of Presentation
	The accompanying consolidated financial statements for the years ended December 31, 2013, 2012 and 2011 have been prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP").
	Use of Estimates
	In the normal course of preparing financial statements in conformity with accounting principles generally accepted in the United States, management is required to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
	Principles of Consolidation
	All subsidiaries are consolidated as they are 100% owned by us. All intercompany transactions and accounts are eliminated in consolidation.
	Significant Accounting Policies
	Cash and Cash Equivalents
	We consider all highly liquid investments with a maturity of three months or less at the date of purchase to be cash equivalents. Cash and cash equivalents are carried at cost, which approximates fair value. We generally place funds that are in excess of current needs in high credit quality instruments such as money market funds. There are no restrictions on the use of cash and cash equivalents.
	Fair Value of Financial Instruments
	Our financial instruments, including cash and cash equivalents, short-term investments, accounts receivable and accounts payable are carried at cost, which approximates their fair values because of the short-term maturity of these instruments and the relative stability of interest rates. See Note 3 for information related to the fair value of our convertible senior notes.
	Fair value is defined as the exit price, or the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants as of the measurement date. There is an established hierarchy for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring the most observable inputs be used when available. Observable inputs are inputs market participants would use in valuing the asset or liability and are developed based on market data obtained from independent sources. Unobservable inputs are inputs that reflect the assumptions about the factors that market participants would use in valuing the asset or liability.
	Foreign Currency Forward Contracts
	We utilize foreign currency forward contracts to hedge certain accounts receivable amounts that are denominated in Japanese Yen, Euros and British Pounds.  These contracts are cash flow hedges used to reduce the risk associated with exchange rate movements, as gains and losses on these contracts are intended to offset exchange losses and gains on underlying exposures.  Foreign currency contracts are typically short-term in duration ranging from one to four months. We do not enter into foreign exchange forward contracts for speculative or trading purposes. Foreign currency contracts are recorded at fair market values and the change in their fair value is recorded as gain or loss in the consolidated statements of operations as a component of Interest income and other, net.
	As of December 31, 2013, we held five open foreign currency forward contracts with a notional value of $7.0 million and a net fair value of approximately $54,000. As of December 31, 2012, we held 20 open foreign currency forward contracts with a notional value of $6.5 million and a net fair value of approximately $99,000. During 2013, net gains related to the change in fair value of such foreign currency forward contracts were $658,000. During 2012 and 2011, net losses related to the change in fair value of such foreign currency forward contracts were not significant. Net gains related to the change in fair value are reported as a component of Interest income and other, net in the consolidated statement of income. The fair value of foreign currency forward contracts are reported as a component of Prepaid and other current expenses in the consolidated balance sheet.
	Investments in Marketable Securities
	We maintain a portfolio of cash equivalents and investments in a variety of fixed and variable rate securities, including U.S. government and federal agency securities, corporate debt securities, and money market funds. The primary objective of our investment activities is to maintain the safety of principal and preserve liquidity while maximizing yields without significantly increasing risk. We do not enter into investments for trading or speculative purposes. We determine the appropriate classification of investments in marketable securities at the time of purchase.  Accretion and amortization of purchase discounts and premiums are included in interest income and other, net. Available-for-sale securities are stated at fair value. The net unrealized gains or losses on available-for-sale securities are reported as a separate component of accumulated other comprehensive income or loss, net of tax. The specific identification method is used to compute realized gains and losses on our marketable securities. In 2013, 2012 and 2011, we had gross realized gains of $4.5 million, $1.3 million and $437,000, respectively. In 2013, 2012 and 2011, gross realized losses were not significant.
	We regularly review our investment portfolio to determine if any security is other-than-temporarily impaired, which would require us to record an impairment charge in the period any such determination is made. In making this judgment, we evaluate, among other things, the duration and extent to which the fair value of a security is less than its cost and our intent and ability to sell, or whether we will more likely than not be required to sell, the security before recovery of its amortized cost basis. We have evaluated our investments as of December 31, 2013 and have determined that no investments with unrealized losses are other-than-temporarily impaired. We do not intend to sell and it is not more likely than not that we would be required to sell these investments before recovery of their amortized cost basis, which may be at maturity.
	It is possible that we could recognize future impairment charges on our investment securities we currently own if future events, new information or the passage of time cause us to determine that a decline in our carrying value is other-than-temporary. We will continue to review and analyze these securities for triggering events each reporting period. See Note 6 for additional information.
	Accounts Receivable and Allowance for Doubtful Accounts
	Trade accounts receivable are recorded at the invoiced amount. The allowance for doubtful accounts is based on our best estimate of the amount of probable credit losses in existing accounts receivable.  We review the allowance for doubtful accounts and provisions are made upon a specific review of all significant past due receivables. For those receivables not specifically reviewed, provisions are provided at a general rate that considers historical write-off experience and other qualitative factors.   Account balances are charged off against the allowance when we believe it is probable the receivable will not be recovered.
	Inventories
	Inventories are goods held for sale in the normal course of business. Inventories are stated at the lower of cost (first-in, first-out) or market. The inventory balance consists of raw materials, work in process (“WIP”) and finished goods. Raw materials include low level components, many of which are purchased from vendors, WIP is partially assembled products and finished goods are products that are ready to be shipped to end customers. Consideration is given to inventory shipped and received near the end of a period and the transaction is recorded when transfer of title occurs. We evaluate inventory for excess and obsolescence and adjust to net realizable value based on inventory that is obsolete or in excess of current demand.
	Property, Plant and Equipment
	Property, plant and equipment are stated at cost less accumulated depreciation. Depreciation of our computer software and equipment is computed using the straight-line method based upon the estimated useful lives of the applicable assets, ranging from three to five years. Building and leasehold improvements are amortized over the lesser of their estimated useful lives or the remaining lease term. Useful lives are evaluated periodically by management in order to determine recoverability in light of current technological conditions. Property, plant and equipment also includes the cost of our products used for research and development which are classified as development equipment and are depreciated over five years to research and development. We also capitalize and depreciate over a two-year period costs of our products used for sales and marketing activities, including product demonstrations for potential customers, which is included in Sales and marketing in the consolidated statements of operations. Repairs and maintenance are charged to expense as incurred while renewals and improvements are capitalized. Upon the sale or retirement of Property, plant and equipment, the accounts are relieved of the cost and the related Accumulated depreciation, with any resulting gain or loss included in the consolidated statements of operations.
	Goodwill
	Goodwill is recorded as the difference, if any, between the aggregate consideration paid for an acquisition and the fair value of the acquired net tangible and intangible assets. Although goodwill is not amortized, we review our goodwill for impairment annually, or more frequently when events occur or circumstances indicate that the carrying amount of goodwill may not be recoverable. The impairment evaluation includes a comparison of the carrying value of the reporting unit to its fair value. If the reporting unit fair value exceeds its carrying value, then no impairment exists. If the fair value does not exceed its carrying value, then additional analysis is performed to determine the amount of any goodwill impairment. We completed our annual goodwill impairment test of our single reporting unit as of December 31, 2013 and determined that there was no impairment.
	Intangible Assets
	Intangible assets consist primarily of acquired intellectual property, such as technologies, customer relationships, and trade names.
	Acquired intangible assets with finite lives, including purchased technology, customer relationships, service agreements, trade names, and non-compete agreements are amortized over their estimated useful lives and reflected in the Amortization of intangible assets line item on our consolidated statements of operations.
	Intangible assets with finite lives are tested for impairment whenever events or circumstances indicate that the carrying amount of an asset (asset group) may not be recoverable. Circumstances which could trigger a review include, but are not limited to: significant adverse change in the extent or manner in which the intangible asset is being used, significant adverse changes in the business climate or legal factors; current period cash flow or operating losses combined with a history of losses or a forecast of continuing losses associated with the use of the asset; or current expectation that the asset will more likely than not be sold or disposed significantly before the end of its estimated useful life.
	An impairment loss is recognized when the carrying amount of an asset exceeds the estimated undiscounted cash flows used in determining the fair value of the asset. The amount of the impairment loss recorded is calculated by the excess of the asset’s carrying value over its fair value. Fair value is generally determined using a discounted cash flow analysis and may involve the use of significant estimates and assumptions, some of which may be based in part on historical experience, forecasted information and discount rates. No such impairment charges were recorded during the years ended December 31, 2013, 2012 and 2011.
	Litigation
	We are a defendant in one class action and in one consolidated shareholder derivative action. We accrue for losses when the loss is deemed probable and the liability can reasonably be estimated. Where a liability is probable and there is a range of estimated loss with no best estimate in the range, we record the minimum estimated liability related to the claim. As additional information becomes available, we assess the potential liability related to our pending litigation and revise our estimates. See Note 10 for additional information.
	Product Warranty
	We generally provide an initial standard warranty (90-day or 12-month periods) on our hardware products after product shipment and accrue for estimated future warranty costs based on actual historical experience and other relevant data, as appropriate, at the time product revenue is recognized. All product warranty expenses associated with our initial standard warranty are reflected within Cost of revenues-products in the accompanying consolidated statements of operations. Accrued product warranty costs are included as a component of accrued expenses and other in the accompanying consolidated balance sheets.
	Activity in the product warranty liability account for the years presented is as follows (in thousands):
			December 31,			December 31,			December 31,
			2013			2012			2011
	Balance at beginning of year		$	665		$	703		$	697
	Current year provision			2,219			629			709
	Acquired liability (Net Optics acquisition)			117			—			—
	Expenditures			(2,355	)		(667	)		(703	)
	Balance at end of year		$	646		$	665		$	703
	Revenue Recognition
	In October 2009, the Financial Accounting Standards Board (“FASB”) issued authoritative guidance for the accounting of multiple-deliverable revenue arrangements, which establishes the accounting and reporting guidance for arrangements including multiple revenue-generating activities. This new authoritative guidance for arrangements with multiple deliverables requires that arrangement consideration be allocated at the inception of an arrangement to all deliverables using the relative selling price method. It also establishes a selling price hierarchy for determining the selling price of each deliverable. The new guidance also eliminates the residual method of allocation for multiple-deliverable revenue arrangements that are outside the scope of software revenue recognition guidance.
	In October 2009, the FASB also issued authoritative guidance for the accounting of certain revenue arrangements that include software elements, which changes the accounting model for revenue arrangements that include both tangible products and software elements that are “essential to the functionality” of the tangible products, and excludes these products from the software revenue accounting guidance.
	We adopted the new guidance on revenue recognition in the first quarter of 2011 on a prospective basis for applicable revenue arrangements originating or materially modified on or after January 1, 2011. The impact of the adoption of the new revenue recognition guidance is to accelerate the timing of revenue recognition principally related to partial shipments of hardware products at the end of accounting periods, which impact may vary from period to period. In periods prior to the adoption of the new guidance, the revenue related to partial shipments of our hardware products which were sold with software deliverables was deferred under the software revenue recognition guidance until the shipment or delivery of all items of a multiple element arrangement had occurred, other than the delivery of post contract customer support and maintenance (“PCS”). PCS was deferred based on established vendor specific objective evidence (“VSOE”) of selling price. As our revenues are generated from the sale of hardware and software products, and related services, a portion of our revenues will continue to be recognized under the software revenue recognition guidance (see below for additional information).
	Sales of our network test hardware products primarily consist of traffic generation and analysis hardware platforms containing multi-slot chassis and interface cards. Our primary network test hardware platform is enabled by our operating system software that is essential to the functionality of the hardware platform. Sales of our network visibility hardware products typically include an integrated, purpose-built hardware appliance with essential, proprietary software. Our software products consist of a comprehensive suite of technology-specific applications for certain of our network test hardware platforms. Our software products are typically installed on and work with these hardware products to further enhance the core functionality of the overall network test system, although some of our software products can be operated independently from our network test platforms.
	Our service revenues primarily consist of technical support, warranty and software maintenance services related to our network test and visibility hardware and software products. Many of our products include up to one year of these services with the initial product purchase and our customers may separately purchase extended services for annual or multi-year periods. Our technical support, warranty and software maintenance services include assistance with the set-up, configuration and operation of our products, repair or replacement of defective products, bug fixes, and unspecified when and if available software upgrades. For certain network test products, our technical support and software maintenance service revenues also include our Application and Threat Intelligence (ATI) service, which provides a comprehensive suite of application protocols, software updates and technical support. The ATI service provides full access to the latest security attacks and application updates for use in real-world test and assessment scenarios. Our customers may purchase the ATI service for annual or multi-year periods. Service revenues also include training and other professional services.
	As our systems typically include hardware and software products, and the related services, we recognize our revenue in accordance with authoritative guidance on both hardware and software revenue recognition. Furthermore, in accordance with the amended revenue recognition guidance, our hardware platform and certain other products that include both tangible products and software elements that function together to deliver the tangible product’s essential functionality have been scoped out of software revenue recognition guidance, and therefore these products are accounted for as hardware products for revenue recognition purposes.
	For our hardware and software products, and related services, we recognize revenue based on the following four criteria: whether (i) evidence of an arrangement exists, which is typically in the form of a customer purchase order; (ii) delivery has occurred (i.e., risks and rewards of ownership have passed to the customer); (iii) the sales price is fixed or determinable; and (iv) collectibility is deemed reasonably assured (or probable for software-related deliverables). Provided that the above criteria are met, revenue from hardware and software product sales is typically recognized upon shipment and service revenues are recognized as the services are provided or completed. Our service revenues from our initial and separately purchased technical support, warranty and software maintenance arrangements are recognized on a straight-line basis over the applicable contractual period.
	Our systems are generally fully functional at the time of shipment and do not require us to perform any significant production, modification, customization or installation after shipment. If our arrangements include acceptance provisions based on customer specified criteria for which we cannot reliably demonstrate that the delivered product meets all the specified criteria, revenue is deferred until the earlier of the receipt of written customer acceptance or the expiration of the acceptance period. In addition, our arrangements generally do not include any provisions for cancellation, termination or refunds.
	Multiple Element Arrangements and Allocation of Value
	Our arrangements with our customers to provide our systems typically include a combination of our hardware and software products, as well as the related technical support, warranty and software maintenance services of these products, and therefore are commonly referred to as multiple element arrangements. When sales arrangements involve hardware and software elements, we use a two-step process to allocate value to each element in the arrangement:
		-1	The total arrangement fee is allocated to the separate non-software deliverables (e.g., chassis, interface cards, and software PCS related to our operating system software that is essential to the functionality of our hardware platform) and the software-related deliverables as a group (e.g., application software and software PCS) based on a relative selling price (“RSP”) method applied to all elements in the arrangement using the selling price hierarchy in the amended revenue recognition guidance as discussed below, and
		-2	The value assigned to the software group for the software deliverables is then allocated to each software element based on the residual method, whereby value is allocated first to the undelivered elements, typically PCS, and the residual portion of the value is then allocated to the delivered elements (typically the software products) and recognized as revenue, provided all other revenue recognition criteria discussed above have been met. The fair value of an element must be based on vendor specific objective evidence (“VSOE”) of the selling price, which typically only exists for technical support, warranty and software maintenance services as discussed below.
	Under the RSP method, the selling price to be used in the allocation of the total arrangement fee to each of the elements, or deliverables, is based on a selling price hierarchy, where the selling price for each element is based on (i) VSOE, if available; (ii) third-party evidence (“TPE”), if available and VSOE is not available; or (iii) the best estimate of selling price (“BESP”), if neither VSOE nor TPE are available.
	We determine VSOE of fair value based on a bell-shaped curve approach, considering the actual sales prices charged to customers when the same element is sold separately, provided it is substantive. All of our products are sold as multiple element arrangement and not sold separately, as our products include an initial period (generally 90-day or 12-month periods) of free technical support, warranty and software maintenance services. Accordingly, we have not established VSOE for nearly all of our products. On a regular basis, we separately sell extended technical support, warranty and software maintenance services upon the expiration of the initial contractual periods included in an initial sales arrangement and have been able to establish VSOE for our technical support, warranty and software maintenance services.
We generally are not able to determine TPE for our products or services because our products are not interchangeable with those of our competitors. Furthermore, we are unable to reliably determine competitive selling prices when the applicable competitive products are sold separately. As such, we use BESP for all of our products and services when allocating the total consideration of multiple element arrangements to each of the deliverables under step one of the allocation process described above except for our technical support, warranty and software maintenance services where we use VSOE. We determine BESP for a product or service by considering multiple factors including, analyzing historical sales price data for standalone and bundled arrangements, published price lists, geographies and customer types. Our estimate of BESP used in our allocation of arrangement consideration requires significant judgment and we review these estimated selling prices on a quarterly basis.
The allocation of value to each deliverable in a multiple element arrangement is completed at the inception of an arrangement, which is typically the receipt of a customer purchase order. The allocated value of each non-software deliverable is then recognized as revenue when each element is delivered, provided all of the other revenue recognition criteria discussed above have been met. For software deliverables, the total software group allocation (or total arrangement consideration for customer orders that include only software products and related services) is allocated based on the residual method which requires that we first allocate value to the undelievered element at vendor specific objective evidence (“VSOE”) of the selling price of the undelivered element and the remaining portion of the arrangement fee is allocated to the delivered elements. As we do not sell our software products without technical support, warranty and software maintenance services, we are unable to establish VSOE for our software products, and therefore use the residual method under the software revenue recognition guidance to allocate the software group (or arrangement) value to each software deliverable. Under the residual method, the software group (or arrangement) value is allocated first to the undelivered elements, typically technical support, warranty and software maintenance services based on VSOE, and the residual portion of the value is then allocated to the delivered elements (typically the software products) and recognized as revenue, provided all other revenue recognition criteria discussed above have been met. If VSOE cannot be established for an undelivered element within the software group (or arrangement), we defer the entire value allocated to the software group (or arrangement) until the earlier of (i) delivery of all elements (other than technical support, warranty and software maintenance services, provided VSOE has been established) or (ii) establishment of VSOE of the undelivered element(s). If the only undelivered element(s) relates to a service for which VSOE has not been established, the entire allocated value of the software group (or arrangement) is recognized as revenue over the longer of the service or contractual period of the technical support, warranty and software maintenance services.
Prior to the adoption of the amended revenue recognition guidance on January 1, 2011, our multiple element arrangements did not go through the two-step allocation process described above. The total arrangement consideration was assigned to each deliverable, including hardware products, based on VSOE in accordance with software revenue recognition guidance as described above. As a result, the substantial majority of our revenue was recognized under the residual method as VSOE was only established for our technical support, warranty and software maintenance services. This resulted in the deferral of revenue at the balance sheet date for partial shipments of multiple element arrangements. Under the amended revenue recognition guidance, we are able to allocate value to our hardware products, based on our best estimate of the selling price, and as a result are now typically able to recognize revenue for our hardware products when delivered, assuming all other revenue recognition criteria noted above have been met.
Sales to Distributors
We use distributors and resellers to complement our direct sales and marketing efforts in certain markets and/or for certain products. Due to the broad range of features and options available with our hardware and software products, distributors and resellers generally do not stock our products and typically place orders with us after receiving an order from an end customer. These distributors and resellers receive business terms of sale similar to those received by our other customers; and payment to Ixia is not contingent on sell-through to and receipt of payment from the end customer. As such, for sales to distributors and resellers, we recognize revenue when the risks and rewards of ownership have transferred to the distributor or reseller provided that the other revenue recognition criteria noted above have been met.
Cost of Revenues
Our cost of revenues related to the sale of our hardware and software products includes materials, payments to third party contract manufacturers, royalties, and salaries and other expenses related to our manufacturing and supply operations personnel. We outsource the majority of our manufacturing operations, and we conduct supply chain management, quality assurance, documentation control, shipping and some final assembly and testing at our facilities in Calabasas, California, Austin, Texas and in Penang, Malaysia. Accordingly, a significant portion of our cost of revenues related to our products consists of payments to our contract manufacturers. Cost of revenues related to the provision of services includes salaries and other expenses associated with technical support services and the cost of extended warranty and maintenance services. Cost of revenues does not include the amortization of purchased technology related to our acquisitions of certain businesses, product lines and technologies of $26.0 million, $20.3 million and $10.8 million for the years ended December 31, 2013, 2012 and 2011, respectively, which are included within our Amortization of intangible assets line item on our consolidated statements of operations.
Research and Development
Research and development expenses consist primarily of salaries and other personnel costs related to the design, development, testing and enhancement of our products. Costs related to research and development activities, including those incurred to establish the technological feasibility of a software product, are expensed as incurred. If technological feasibility is established, all development costs incurred until general product release are subject to capitalization. To date, establishment of technological feasibility of our products and general release have substantially coincided. As a result, we have not capitalized any development costs.
Software Developed for Internal Use
We capitalize costs of software, consulting services, hardware and payroll-related costs incurred to purchase or develop internal-use software in accordance with the authoritative guidance on accounting for the costs of computer software developed or obtained for internal use. Internally developed software includes enterprise-level business software that we are customizing to meet our specific operational needs. To date, internal costs incurred to purchase or develop software for internal use have not been significant. Internally developed software is amortized over five years. Purchased software is amortized over three years.
Advertising
Advertising costs are expensed as incurred. Advertising costs included in sales and marketing were $2.9 million, $2.0 million and $1.1 million for the years ended December 31, 2013, 2012 and 2011, respectively.
Acquisition and Other Related Costs
Acquisition and other related costs are expensed as incurred and consist primarily of transaction and integration related costs such as success-based banking fees, professional fees for legal, accounting, tax, due diligence, valuation and other related services, change in control payments, amortization of deferred compensation, consulting fees, required regulatory costs, certain employee, facility and infrastructure transition costs, and other related expenses. We expect our acquisition and other related expenses to fluctuate over time based on the timing of our acquisitions and related integration activities.
Stock-Based Compensation
Share-based payments, including grants of stock options, restricted stock units and employee stock purchase rights, are required to be recognized in the financial statements based on the estimated fair values for accounting purposes on the grant date. We use the Black-Scholes option pricing model to estimate the fair value for accounting purposes of stock options and employee stock purchase rights. We use the grant date closing share sales price of a share of our common stock to estimate the fair value for accounting purposes of restricted stock units. The determination of the fair value of share-based awards utilizing the Black-Scholes model is affected by our stock price and a number of assumptions, including expected volatility, expected life and risk-free interest rate. The expected life and expected volatility are estimated based on historical data. The risk-free interest rate assumption is based on U.S. constant maturities over the expected life of the award. Stock-based compensation expense recognized in our consolidated financial statements is based on awards that are ultimately expected to vest. The amount of stock-based compensation expense is reduced for estimated forfeitures based on historical experience as well as future expectations. Forfeitures are required to be estimated at the time of grant and revised, if necessary, in subsequent periods if estimated and actual forfeitures differ from these initial estimates. We evaluate the assumptions used to value share-based awards on a periodic basis. We recognize stock-based compensation expense based on the graded, or accelerated multiple-option, approach over the vesting period.
We have outstanding share-based awards that have performance-based vesting conditions. Awards with performance-based vesting conditions require the achievement of certain financial or other performance criteria as a condition to the vesting. We recognize the estimated fair value of performance-based awards, net of estimated forfeitures, as stock-based compensation expense over the performance period, using graded approach, based upon our determination of whether it is probable that the performance targets will be achieved. At each reporting period, we reassess the probability of achieving the performance criteria and the performance period required to meet those targets. Determining whether the performance criteria will be achieved involves judgment, and the estimate of stock-based compensation expense may be revised periodically based on changes in the probability of achieving the performance criteria. Revisions are reflected in the period in which the estimate is changed. If performance goals are not met, no stock-based compensation expense is recognized, and, to the extent stock-based compensation was previously recognized, such stock-based compensation is reversed.
Income Taxes
We account for income taxes using the liability method. Deferred taxes are determined based on the differences between the financial statement and tax bases of assets and liabilities, using enacted tax rates in effect for the year in which the differences are expected to reverse. Valuation allowances are established when necessary to reduce deferred tax assets to the amounts expected more likely than not to be realized.
We recognize, in our consolidated financial statements, the impact of tax positions that are more likely than not to be sustained upon examination based on the technical merits of the positions. See Note 9 for additional information.
Earnings Per Share
Basic earnings per share is computed using the weighted-average number of common shares outstanding during the period. Diluted earnings per share is computed using the weighted-average number of common shares and dilutive potential common shares outstanding during the period. Dilutive potential common shares primarily consist of shares underlying our convertible senior notes, employee stock options and restricted stock units. See Note 13 for additional information.
Foreign Currency Translation and Transactions
Assets and liabilities of non-U.S. subsidiaries that operate in a local currency environment are translated to U.S. Dollars at exchange rates in effect at the balance sheet date, with the resulting translation adjustments included as a separate component in accumulated other comprehensive income (loss). Income and expense accounts are translated at average exchange rates during the year. Where the U.S. Dollar is the functional currency, certain balance sheet and income statement accounts are remeasured at historical exchange rates and translation adjustments from the remeasurement of the local currency amounts to U.S. Dollars are included in interest income and other, net. During the years ended December 31, 2013, 2012 and 2011, we had net foreign currency income and (losses) of $267,000, ($519,000) and ($672,000), respectively, attributable to our foreign operations, which includes net gains and losses on forward contracts.
Comprehensive Income
Comprehensive income (loss) includes all changes in equity (net assets) during a period from non-owner sources. Accumulated other comprehensive income (loss) includes unrealized gains and losses on investments and foreign currency translation adjustments.
Segments
Operating segments are defined as components of an enterprise engaged in business activities for which discrete financial information is available and regularly reviewed by the chief operating decision maker (“CODM”) of the enterprise to make decisions about resources to be allocated to the segment and to assess its performance. Our CODM is our Acting Chief Executive Officer who reviews our consolidated budgets and results for the purposes of allocating resources and evaluating financial performance.  Accordingly, we have determined that we operated within one business segment as of, and for the years ended, December 31, 2013, 2012 and 2011. See Note 5 for entity-wide disclosures about products and services, geographic areas and major customers.
Recent Accounting Pronouncements
During May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers, which provides new guidance on the recognition of revenue and states that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The standard will be effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early adoption is not permitted. We have not evaluated the impact of the adoption of this accounting standard update on our consolidated financial position or results of operations.
In July 2013, the Financial Accounting Standards Board (“FASB”) issued changes to the presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists. These changes require an entity to present an unrecognized tax benefit as a liability in the financial statements if (i) a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is not available at the reporting date under the tax law of the applicable jurisdiction to settle any additional income taxes that would result from the disallowance of a tax position, or (ii) the tax law of the applicable jurisdiction does not require the entity to use, and the entity does not intend to use, the deferred tax asset to settle any additional income taxes that would result from the disallowance of a tax position. Otherwise, an unrecognized tax benefit is required to be presented in the 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. Previously, there was diversity in practice as no explicit guidance existed. The effective date for this disclosure guidance is for fiscal years beginning after December 15, 2013 and is consistent with our current practices.
In February 2013, FASB issued ASU No. 2013-02, Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income Under this standard, entities will be required to disclose additional information with respect to changes in accumulated other comprehensive income (AOCI) balances by component and significant items reclassified out of AOCI. Expanded disclosures for presentation of changes in AOCI involve disaggregating the total change of each component of other comprehensive income (for example, unrealized gains or losses on available for sale marketable securities) as well as presenting separately for each such component the portion of the change in AOCI related to (1) amounts reclassified into income and (2) current-period other comprehensive income. Additionally, for amounts reclassified into income, disclosure in one location would be required, based upon each specific AOCI component, of the amounts impacting individual income statement line items. Disclosure of the income statement line item impacts will be required only for components of AOCI reclassified into income in their entirety. Therefore, disclosure of the income statement line items affected by AOCI components such as net periodic benefit costs would not be included. The disclosures required with respect to income statement line item impacts would be made in either the notes to the consolidated financial statements or parenthetically on the face of the consolidated statements of operations. The effective date for this disclosure guidance was for fiscal years beginning after December 15, 2012. We adopted this new guidance prospectively in the quarter ended March 31, 2013 by including the appropriate disclosures. The implementation of this update did not impact our financial position, results of operations or cash flows as it was disclosure-only in nature.
In July 2012, the FASB issued ASU No. 2012-02, Testing Indefinite-Lived Intangible Assets for Impairment. Under this standard, entities testing long-lived intangible assets for impairment now have an option of performing a qualitative assessment to determine whether further impairment testing is necessary. If an entity determines, on the basis of qualitative factors, that the fair value of the indefinite-lived intangible asset is more-likely-than-not less than the carrying amount, the existing quantitative impairment test is required. Otherwise, no further impairment testing is required. The effective date for this disclosure guidance is for fiscal years beginning after December 15, 2012, with early adoption permitted. We adopted this new guidance on January 1, 2013. The adoption of this new guidance did not have a significant impact on our consolidated financial position, results of operations and cash flows.

Note_2_Acquisitions

Note 2 - Acquisitions	12 Months Ended
	Dec. 31, 2013
Business Combinations [Abstract]	'
Business Combination Disclosure [Text Block]	'
		2	Acquisitions
	VeriWave, Inc.
	On July 18, 2011, we completed our acquisition of all of the capital stock of VeriWave, Inc. (“VeriWave”).  The aggregate purchase price totaled $15.8 million, and was funded from our existing cash and cash equivalents.
	For the year ended December 31, 2012, acquisition and other related costs related to the VeriWave transaction were not significant. For the year ended December 31, 2011, acquisition and other related costs, including integration activities were $972,000. These acquisition and other related costs have been expensed as incurred, and have been included within the Acquisition and other related expenses line item on our consolidated statements of operations.
	The following table summarizes the allocation of the purchase price to the estimated fair values of the assets acquired and liabilities assumed at the date of acquisition (in thousands):
	Cash and cash equivalents		$	235
	Accounts receivable			1,660
	Inventories			320
	Prepaid and other assets			268
	Identifiable intangible assets			8,800
	Goodwill			7,045
	Total assets acquired			18,328
	Accounts payable and accrued expenses			(2,020	)
	Deferred revenues			(500	)
	Net assets acquired		$	15,808
	The identifiable intangible assets of $8.8 million consist of $4.3 million of acquired technology, $3.5 million of customer relationships, and $1.0 million of other identifiable intangible assets. These intangible assets will be amortized using a straight-line method over their expected useful lives ranging from six months to six years. The goodwill recorded in the United States in connection with this transaction is not deductible for income tax purposes. We do not consider the acquisition of VeriWave material for further disclosure.
	Anue Systems, Inc.
	On June 1, 2012, we completed our acquisition of all of the outstanding shares of capital stock and other equity interests of Anue Systems, Inc. (“Anue”).  Anue provides solutions to monitor and test complex networks, including Anue’s Net Tool Optimizer solution that efficiently aggregates and filters network traffic to help optimize network monitoring tool usage.  With this acquisition, we have expanded our addressable market, broadened our product portfolio and grown our customer base.  In addition, we are leveraging Anue’s sales channels and assembled workforce, including its experienced development team.  These factors, among others, contributed to a purchase price in excess of the estimated fair value of Anue’s net identifiable assets acquired (see summary of net assets below), and, as a result, we have recorded goodwill in connection with this transaction.
	In the second quarter of 2013, we finalized our purchase price allocation. The aggregate cash consideration paid totaled $152.4 million and was funded from our existing cash and sale of investments.
	Acquisition and other related costs, including integration activities, approximated $269,000 and $4.9 million for the years ended December 31, 2013 and 2012, respectively. These acquisition and other related costs have been expensed as incurred and have been included within the Acquisition and other related line item on our consolidated statements of operations.
	The following table summarizes the allocation of the purchase price to the estimated fair values of the assets acquired and liabilities assumed at the date of acquisition (in thousands):
	Cash and cash equivalents		$	3,659
	Accounts receivable			12,016
	Inventories			4,380
	Prepaid and other assets			2,980
	Fixed assets			1,600
	Identifiable intangible assets			74,700
	Goodwill			91,008
	Total assets acquired			190,343
	Accounts payable, accrued expenses and other liabilities			(7,942	)
	Deferred revenues			(6,997	)
	Deferred tax liability, net			(22,964	)
	Net assets acquired		$	152,440
	During 2013, we updated the allocation of our purchase price to increase the value of our accounts receivable balance by $173,000, decrease accounts payable, accrued expenses and other liabilities by $172,000, and decrease our deferred tax liability, net by $22,000, resulting in a net decrease in goodwill of $367,000. As these changes were not material, we did not recast our prior period financial statements for such changes. The above table reflects these changes.
	The identifiable intangible assets of $74.7 million consist of $45.0 million of acquired technology, $21.9 million of customer relationships, $4.0 million for the trade name, $2.1 million related to non-compete agreements and $1.7 million of other identifiable intangible assets. The fair values of the identifiable intangible assets have been estimated using the income approach, which includes the discounted cash flow and relief-from-royalty methods. These intangible assets will be amortized using a straight-line method over their expected useful lives ranging from six months to six years.  The goodwill recorded in connection with this transaction is not deductible for U.S. income tax purposes.
	BreakingPoint Systems, Inc.
	On August 24, 2012, we completed our acquisition of all of the outstanding shares of capital stock of BreakingPoint Systems, Inc. (“BreakingPoint”).  BreakingPoint is a leader in security testing, and its solutions provide global visibility into emerging threats and applications, along with advance insight into the resiliency of an organization’s information technology infrastructure under operationally relevant conditions and malicious attacks. With this acquisition, we have expanded our addressable market, broadened our product portfolio and grown our customer base. In addition, we are leveraging BreakingPoint’s sales channels and assembled workforce, including its experienced product development and sales teams. These factors, among others, contributed to a purchase price in excess of the estimated fair value of BreakingPoint’s net identifiable assets acquired (see summary of net assets below), and, as a result, we have recorded goodwill in connection with this transaction.
	In the third quarter of 2013, we finalized our purchase price allocation. The aggregate cash consideration paid totaled $163.7 million and was funded from our existing cash and sale of investments.
	Acquisition and other related costs, including integration activities, approximated $2.1 and $6.9 million for the years ended December 31, 2013 and 2012, respectively. These acquisition and other related costs have been expensed as incurred, and have been included within the Acquisition and other related line item on our consolidated statements of operations.
	In connection with the acquisition, we may be obligated to pay up to $3.2 million to certain pre-acquisition employees of BreakingPoint over a weighted average period of less than two years provided they remain employees of Ixia. As of December 31, 2013, we have paid $2.4 million related to this obligation. For the years ended December 31, 2013 and 2012, $1.1 million and $2.1 million was expensed and recorded within the Acquisition and other related line item on our consolidated statements of operations. The remaining accrual was included as a component of Accrued expenses and other in our consolidated balance sheets.
	The following table summarizes the allocation of the purchase price to the estimated fair values of the assets acquired and liabilities assumed at the date of acquisition (in thousands):
	Cash and cash equivalents		$	13,417
	Accounts receivable			4,610
	Inventories			3,156
	Prepaid and other assets			796
	Fixed assets			936
	Identifiable intangible assets			65,600
	Goodwill			102,330
	Total assets acquired			190,845
	Accounts payable, accrued expenses and other liabilities			(6,889	)
	Deferred revenues			(6,387	)
	Deferred tax liability, net			(13,882	)
	Net assets acquired		$	163,687
	During 2013, we updated the preliminary allocation of our purchase price to increase the value of our accounts receivable balance by $58,000, decrease the value of our deferred tax liability balance by $264,000 and decrease goodwill by $322,000. As these changes were not material, we did not recast our prior period financial statements for such changes. The above table reflects these changes.
	The identifiable intangible assets of $65.6 million consist of $22.7 million of acquired technology, $20.6 million of customer relationships, $16.6 million of service agreements, $2.9 million for the trade name, $2.2 million related to non-compete agreements and $600,000 of other identifiable intangible assets. The fair values of the identifiable intangible assets have been estimated using the income approach, which includes the discounted cash flow and relief-from-royalty methods. These intangible assets will be amortized using a straight-line method over their expected useful lives ranging from two weeks to six years.  The goodwill recorded in connection with this transaction is not deductible for U.S. income tax purposes.
	Net Optics, Inc.
	On December 5, 2013, we completed our acquisition of all of the outstanding shares of common stock and all other equity interests of Net Optics, Inc. (“Net Optics”). Net Optics is a leading provider of total application and network visibility solutions. With this acquisition, we have expanded our product portfolio, strengthened our service provider and enterprise customer base and broadened our sales channel and partner programs. In addition, we expect to realize certain operational synergies and leverage Net Optics’ existing sales channels, partner relationships and assembled workforce, including its experienced product development team in Santa Clara and its global sales force. These factors, among others, contributed to a purchase price in excess of the estimated fair value of Net Optics’ net identifiable assets acquired (see summary of net assets below), and, as a result, we have recorded goodwill in connection with this transaction.
	The aggregate purchase price totals $193.8 million and is subject to certain post-closing adjustments including an adjustment based on the final amount of Net Optics’ closing net working capital and tax reimbursements to sellers. The acquisition was funded from our existing cash and sale of investments.
	Acquisition and other related costs, including integration activities, approximated $4.0 million for the year ended December 31, 2013. These acquisition and other related costs have been expensed as incurred, and have been included within the Acquisition and other related line item on our consolidated statements of operations. The preliminary purchase price allocation is pending the completion of certain items, such as the final tax attributes that will be determined upon the filing of certain pre-acquisition tax returns and the final purchase price adjustments that will be determined once the closing balance sheet is finalized and agreed to by both parties.
	The following table summarizes the preliminary allocation of the purchase price to the estimated fair values of the assets acquired and liabilities assumed at the date of acquisition (in thousands):
	Cash and cash equivalents		$	1,967
	Accounts receivable			9,253
	Inventories			6,543
Prepaid and other assets			1,742
Fixed assets,			2,976
Identifiable intangible assets			72,858
Goodwill			112,064
Total assets acquired			207,403
Accounts payable, accrued expenses and other liabilities			(8,441	)
Deferred revenues			(5,170	)
Net assets acquired		$	193,792
The identifiable intangible assets of $72.9 million consist of $50.0 million of acquired technology, $15.8 million of customer relationships and related service agreements, $3.7 million related to non-compete agreements, $3.0 million for the trade name, and $0.4 million of other identifiable intangible assets. The fair values of the identifiable intangible assets have been estimated using the income approach, which includes the discounted cash flow and relief-from-royalty methods. These intangible assets will be amortized using a straight-line method over their expected useful lives ranging from four months to seven years. The goodwill recorded in connection with this transaction is tax deductible for U.S. income tax purposes.
Pro Forma and Post Acquisition Results (Unaudited)
The following table summarizes the unaudited pro forma total revenues and net income of the combined entities, including Ixia, had the acquisition of Net Optics occurred January 1, 2012, and the acquisitions of Anue and BreakingPoint had occurred on January 1, 2011 (in thousands):
		Year Ended
		December 31,
		2013			2012			2011
Total revenues		$	516,767		$	514,075		$	382,192
Net income			(2,097	)		(2,006	)		46,441
The pro forma combined results in the table above have been prepared for comparative purposes only and include acquisition related adjustments for, among others items, reductions in revenues and increases in costs related to the estimated fair value adjustments to deferred revenues and inventory, respectively, certain acquisition related costs, amortization of identifiable intangible assets, and the related income tax effects for these adjustments (including to record the $22.7 million and $12.1 million partial releases of our valuation allowance in the first quarter of 2011 rather than in the second and third quarters of 2012, respectively). The pro forma combined results in the table above excluded the impact of the VeriWave acquisition as such results were not material.
Post-acquisition results for Net Optics operations have been included in our consolidated financial statements since the acquisition date (i.e., December 5, 2013), which approximated $4.8 million of total revenues and a loss before income taxes of approximately $1.9 million for the year ended December 31, 2013. Post-acquisition results for Anue and BreakingPoint’s operations have been included in our consolidated financial statements, which include combined revenues of $54.9 million and a combined loss before income taxes of approximately $7.9 million for the year ended December 31, 2012, respectively.
The pro forma combined results, as well as those of Net Optics included in our results subsequent to the acquisition date, do not purport to be indicative of the results of operations which would have resulted had the acquisition been effective at the beginning of the applicable periods noted above, or the future results of operations of the combined entity.

Note_3_Long_Term_Debt

Note 3 - Long Term Debt	12 Months Ended
	Dec. 31, 2013
Disclosure Text Block [Abstract]	'
Long-term Debt [Text Block]	'
		3	Long Term Debt
	Convertible Senior Notes
	On December 7, 2010, we issued $200.0 million in aggregate principal amount of 3.00% Convertible Senior Notes (the “Notes”) due December 15, 2015 unless earlier repurchased or converted. The unsecured Notes were offered and sold only to qualified institutional buyers pursuant to Rule 144A under the Securities Act of 1933, as amended (the “Securities Act”). The Notes are governed by the terms of an indenture agreement (the “Indenture”) dated December 7, 2010, which was filed with the Securities and Exchange Commission (the “SEC”) on December 8, 2010.
	The Notes bear interest at a rate of 3.00% per year, payable semiannually in arrears on June 15 and December 15 of each year, which began on June 15, 2011. We may in certain instances be required to pay additional interest if the Notes are not freely tradable by the holders thereof (other than our affiliates) beginning six months after the date of issuance and in connection with events of default, including events of default relating to our failure to comply with our reporting obligations to the trustee and the SEC. After a default under the Indenture, if the trustee or the holders of at least 25% in aggregate principal amount of the Notes give us notice of, and direct us to cure, the default and the default is not cured within 60 days thereafter, then unless a waiver is obtained from the holders of more than 50% in aggregate principal amount of the Notes, an event of default will occur under the Indenture. Upon any such event of default, we may elect that for the first 180 days (or such lesser amount of time during which the event of default continues), the sole remedy be the payment of additional interest at an annual rate equal to 0.50%. In the event that such additional interest becomes payable because of our failure to timely file certain reports with the SEC and the trustee, the filing of such reports will cure the event of default and the interest rate will be reduced (so long as no other events of default then exist). If we elect to pay such additional interest and the event of default is not cured within the 180-day period, or if we do not make such an election to pay additional interest when the event of default first occurs, the trustee or the holders of at least 25% in aggregate principal amount of the Notes may declare the Notes to be due and payable immediately. During 2013, 2012 and 2011, we made interest payments of $6.0 million in all respective years.
	Debt issuance costs were approximately $6.0 million, which were capitalized to deferred issuance costs and are being amortized to interest expense over the five year term of the Notes using the straight-line method. During each of 2013, 2012 and 2011, we charged amortization expense of $1.2 million to interest expense pertaining to deferred issuance costs.
	The Notes are convertible at any time prior to the close of business on the third business day immediately preceding the maturity date at the holder’s option, into shares of our Common Stock at an initial conversion rate of 51.4536 shares per $1,000 principal amount of Notes, which represents an initial conversion price of approximately $19.43 per share. The conversion rate is subject to adjustment for certain events that occur prior to maturity, such as a change in control transaction as defined in the Indenture.
	We may not redeem the Notes prior to the maturity date. If a fundamental change (such as a change in control event or if our Common Stock ceases to be listed or quoted on any of the New York Stock Exchange, the Nasdaq Global Select Market or the Nasdaq Global Market or any of their respective successors) occurs prior to the maturity date, holders may require us to repurchase for cash all or part of their Notes at a repurchase price equal to 100% of the principal amount of the Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date.
	The Indenture provides for customary events of default (subject in certain cases to grace and cure periods) including, without limitation, (i) the failure to pay amounts due under the Notes, (ii) the failure to deliver the shares of our Common Stock due upon conversion of any Note, (iii) our failure to comply with other agreements contained in the Indenture or in the Notes, (iv) payment defaults on, or acceleration of, other indebtedness, (v) the failure to pay certain judgments, and (vi) certain events of bankruptcy, insolvency or reorganization with respect to the Company. An event of default under the Indenture (other than an event of default related to certain events of bankruptcy, insolvency or reorganization) will allow either the trustee or the holders of at least 25% in aggregate principal amount of the then outstanding Notes to cause the acceleration of the Notes. An event of default related to certain events of bankruptcy, insolvency or reorganization with respect to the Company will automatically cause the acceleration of the Notes.
	On or about May 1, 2014, the trustee provided us with notice that we were in default under the Indenture because we had not timely filed with the trustee this Form 10-K, our Quarterly Report on Form 10-Q for the quarter ended September 30, 2013 (the “2013 Third Quarter Form 10-Q”) and a Current Report on Form 8-K/A relating to our acquisition of Net Optics in December 2013. We expect to cure such defaults on or about the date of the filing of this Form 10-K by filing with the SEC and the trustee all such delinquent reports. We are also currently in default of our obligation under the Indenture to timely file with the trustee our Quarterly Report on Form 10-Q for the quarter ended March 31, 2014 (the “2014 First Quarter Form 10-Q”). The trustee or the holders of at least 25% of aggregate principal amount of the Notes may elect to give us notice of such default and to demand that we cure it. As of the date of the filing of this Form 10-K with the SEC, no such notice has been given.
	Because we have been delinquent in the filing of certain of our periodic financial reports with the SEC, we are not in compliance with the Nasdaq listing rule that requires us to timely file such reports with the SEC. On May 2, 2014, Nasdaq’s Listing Qualifications Department notified us that, due to our delay in filing with the SEC this Form 10-K and our 2013 Third Quarter Form 10-Q, our common stock would be delisted unless we timely requested a hearing before a Nasdaq Listings Qualification Panel (a “Panel”). We timely requested such a hearing, which was held on June 12, 2014. At the hearing, we presented a plan to regain compliance with the rule and requested an extension of time in which to do so. The delisting of our common stock has been stayed until the Panel’s decision regarding our listing status. On May 15, 2014, Nasdaq advised us that the delayed filing of the 2014 First Quarter Form 10-Q serves as an additional basis for the delisting determination. After filing this Form 10-K and the 2013 Third Quarter Form 10-Q with the SEC, we will continue to be delinquent in our filing of periodic financial reports with the SEC due to our delay in filing the 2014 First Quarter Form 10-Q.
	As of December 31, 2013 and 2012, the estimated fair value of our $200.0 million principal convertible senior notes approximated $215.7 million and $230.1 million, respectively. The estimated fair value of the Notes was determined based on the market price of the Notes as of December 31, 2013 and 2012, which are based on Level 2 inputs.
	Senior Secured Revolving Credit Facility
	On December 21, 2012, we entered into a credit agreement (the “Credit Facility Agreement”) establishing a senior secured revolving credit facility (the “Credit Facility”) with certain institutional lenders and Bank of America, N.A., as administrative agent, that provides for an aggregate loan amount of up to $150.0 million. The Credit Facility is expected to mature on December 21, 2016, but may mature on September 14, 2015 if we do not have available liquidity (domestic cash and investments, plus availability under the Credit Facility) of $25.0 million in excess of the amount required to repay our Notes of $200.0 million in full beginning on June 15, 2015. If we satisfy this requirement between June 15, 2015 and September 14, 2015, but fail to do so after September 15, 2015 and prior to December 15, 2015, the maturity date is the date on which the requirement is no longer satisfied.
	The Credit Facility, which includes a sublimit of up to $25.0 million for the issuance of standby letters of credit and a swingline facility of up to $15.0 million, to be used, among other things, to fund our working capital needs, to fund capital expenditures and for other general corporate purposes (including acquisitions), stock repurchases and any partial refinancing of our Notes. We may from time to time request an increase to the Credit Facility by an amount of up to $50.0 million, which increase would be subject to the consent of the lender or lenders (if any) assuming the increased obligations.
	Borrowings under the Credit Facility bear interest at either (i) the Base Rate, which is equal to the highest of (a) the administrative agent’s prime rate, (b) the federal funds rate plus 0.50% and (c) the London Interbank Offered Rate ("LIBOR") for a one-month interest period plus 1.00% or (ii)  LIBOR plus the applicable margin. The applicable margin ranges are from 1.75% to 2.25% for LIBOR loans and 0.75% to 1.25% for Base Rate loans, and depends on the Company’s total leverage ratio (as defined in the Credit Facility Agreement). Interest is payable quarterly. No amounts were drawn down under this Credit Facility as of December 31, 2013.
	Our obligations under the Credit Facility are guaranteed by Net Optics, Inc., Anue Systems, Inc., BreakingPoint Systems, Inc., Catapult Communications Corporation and VeriWave, Inc., all of which are wholly owned domestic subsidiaries of Ixia, and by any future domestic or foreign subsidiaries of Ixia or such guarantors, provided that no foreign subsidiary will be required to become a guarantor to the extent the guaranty would result in a material adverse tax consequence to the Company. The Credit Facility is secured by a first priority security interest in substantially all existing and after acquired tangible and intangible personal property of Ixia and of the guarantors and by the pledge by Ixia and by the guarantors of all outstanding equity securities of their respective domestic subsidiaries and 65% of the outstanding equity securities of directly owned foreign subsidiaries.
	Debt issuance costs were approximately $947,000 which were capitalized to deferred issuance costs and are being amortized as interest expense over the expected four year term of the Credit Facility using the straight-line method, which is not materially different from the effective interest method. Amortization recorded to interest expense pertaining to debt issuance was $270,000 in 2013 and the amount was not significant in 2012.
	We are required to pay a commitment fee on the unused portion of the Credit Facility of up to a maximum of $450,000 or 0.30% depending on the Company’s total leverage ratio.
	The Credit Facility Agreement requires the Company to comply with certain covenants, including maintaining (i) an interest coverage ratio (as defined in the Credit Facility Agreement) of greater than 3.50 to 1.00, measured quarterly on a trailing twelve months basis and (ii) a maximum leverage ratio (as defined in the Credit Facility Agreement) of not greater than 3.50 to 1.00 through June 30, 2014 and 3.00 to 1.00 thereafter, measured quarterly on a trailing twelve months basis. The Credit Facility Agreement also requires us to timely provide certain periodic financial statements to the lenders. In connection with the delayed delivery to the lenders of our financial statements for the quarters ended September 30, 2013, December 31, 2013 and March 31, 2014 and of our audited financial statements for the fiscal year ended December 31, 2013, we have entered into agreements with the lenders that amended the Credit Facility Agreement to extend the dates for such deliveries. We otherwise would have been in breach of certain covenants under the Credit Facility Agreement. Most recently, on June 12, 2014, we amended the Credit Facility Agreement to extend the date for delivery of (i) our audited financial statements for the fiscal year ended December 31, 2013 to June 20, 2014 and (ii) our financial statements for the quarter ended March 31, 2014 to June 27, 2014. The Company intends to deliver such audited financial statements to the lenders on the date of the filing of this Form 10-K with the SEC. If the financial statements for the quarter ended March 31, 2014 are not delivered to the lenders on or before June 27, 2014, then unless a subsequent extension or waiver is provided by the lenders, we will be in breach of this covenant under the Credit Facility Agreement.
	Effective April 30, 2014, we entered into a waiver agreement with the lenders that included a waiver of any breach of the Credit Facility Agreement (which requires us to comply with the Indenture governing our Notes) arising out of our failure to comply with certain covenants in the Indenture. Those covenants require us to timely file with the trustee under the Indenture our periodic financial and other reports that we are required to file with the SEC, and to make our SEC filings on a timely basis. Under the waiver, the lenders temporarily waived any default arising out of our failure to timely file with the trustee (i) our 2013 Third Quarter Form 10-Q, (ii) this Form 10-K and (iii) a Current Report on Form 8-K/A relating to our acquisition of Net Optics that was due to be filed with the SEC no later than on February 18, 2014. The temporary waiver automatically expires on the earlier of (i) 60 days after receipt of notice from either the trustee or the holders of 25% of the principal amount of the Notes demanding that remedial action be taken in respect of the delayed filings (such a notice was given by the trustee on or about May 1, 2014) and (ii) the occurrence of any other default or event of default under the Indenture. Our need for this waiver will expire upon the filing with the SEC of (i) our 2013 Third Quarter Form 10-Q, (ii) this Form 10-K and (iii) our Current Report on Form 8-K/A relating to Net Optics.
	On May 15, 2014, we entered into an amendment and waiver agreement with the lenders that included a waiver from the lenders of any breach of the Credit Facility Agreement (which requires us to comply with the Indenture governing our Notes) arising out of our failure to comply with the covenant in the Indenture that requires us to timely file with the trustee our 2014 First Quarter Form 10-Q. This waiver is only effective as long as (i) no event of default occurs under the Indenture due to our failure to complete any necessary remedial action in respect of the delayed filing within 60 days of receipt of notice from either the trustee under the Indenture or the holders of 25% of the principal amount of our Notes demanding such remedial action (as of the date of the filing of this Form 10-K with the SEC, no such notice has been given) and (ii) no delisting of our common stock from the Nasdaq Global Select Market occurs.
	The Credit Facility Agreement also provides for customary events of default (subject to grace and cure periods in certain cases) including, without limitation, (a) failure to pay (with no grace period for the nonpayment of principal); (b) defaults under other documents executed and delivered in connection with the Credit Facility Agreement; (c) bankruptcy or the commencement of insolvency proceedings, including the appointment of a receiver; (d) changes of control; and (e) failure to perform or observe covenants contained in the Credit Facility Agreement or related documents. Upon the occurrence of an event of default, the principal and accrued interest under the Credit Facility then outstanding may be declared due and payable. An event of default related to certain events of bankruptcy, insolvency or reorganization with respect to the Company will automatically cause the acceleration of payment of the unpaid principal and accrued interest of all outstanding loans.

Note_4_Restructuring_Costs

Note 4 - Restructuring Costs	12 Months Ended
	Dec. 31, 2013
Restructuring and Related Activities [Abstract]	'
Restructuring and Related Activities Disclosure [Text Block]	'
		4	Restructuring Costs
	During the third quarter of 2012, our management approved, committed to and initiated a plan to restructure our operations following our August 24, 2012 acquisition of BreakingPoint (“BreakingPoint Restructuring”). The BreakingPoint Restructuring included a net reduction in force of approximately 29 positions (primarily impacting our research and development team in Melbourne, Australia). For the year ended December 31, 2012, we recognized restructuring costs of approximately $4.1 million, and of this amount, $2.7 million primarily related to one-time employee termination benefits consisting of severance and other related costs and $1.4 million related to facility costs associated with the closure of our office in Melbourne, Australia and other costs, which were recorded to the Restructuring line item within our consolidated statement of operations. As of December 31, 2012, $1.0 million of such costs were accrued to the Accrued expenses and other line item within our consolidated balance sheets. The BreakingPoint Restructuring was substantially completed during the fourth quarter of 2012. The remaining accrual relates primarily to lease termination costs which are expected to be paid by the end of the second quarter of 2015.
	During the fourth quarter of 2013, our management approved, committed to and initiated a plan to restructure our Test operations (“Test Restructuring”). The Test Restructuring included a net reduction in force of approximately 120 positions, (primarily impacting our research and development team in Bangalore, India), which represented approximately 6.5% of our worldwide work force. For the year ended December 31, 2013, we recognized restructuring costs of approximately $1.8 million, primarily related to one-time employee termination benefits consisting of severance and other related costs, which were recorded to the Restructuring line item within our consolidated statement of operations. As of December 31, 2013, $1.1 million of such costs were accrued to the Accrued expenses and other line item within our consolidated balance sheets. The Test Restructuring was substantially completed during the fourth quarter of 2013.
	Activity related to our restructuring plans are as follows (in thousands):
			Total			BreakingPoint			Test
						Restructuring			Restructuring
	Accrual at December 31, 2011		$	-		$	-		$	-
	Charges			4,077			4,077			-
	Payments			(2,275	)		(2,275	)		-
	Non-cash items			(776	)		(776	)		-
	Accrual at December 31, 2012			1,026			1,026			-
	Charges			1,833			51			1,782
	Payments			(1,161	)		(474	)		(687	)
	Non-cash items			(191	)		(191	)		-
	Accrual at December 31, 2013		$	1,507		$	412		$	1,095

Note_5_Concentrations

Note 5 - Concentrations	12 Months Ended
	Dec. 31, 2013
Risks and Uncertainties [Abstract]	'
Concentration Risk Disclosure [Text Block]	'
		5	Concentrations
	Credit Risk
	Financial instruments that subject us to concentrations of credit risk consist primarily of cash and cash equivalents, investments and trade accounts receivable. We maintain our cash and cash equivalents with financial institutions that management deems reputable, and at times, cash balances may be in excess of FDIC insurance limits. We extend differing levels of credit to customers, typically do not require collateral, and maintain reserves for potential credit losses based upon the expected collectability of accounts receivable.
	Revenue by Product Line
	We have two product lines: Network Test Solutions and Network Visibility Solutions. Our Network Test products include our multi-slot test chassis and appliances, our traffic generation interface cards, our suite of test applications, and the related technical support, warranty and software maintenance services, including our Application and Threat Intelligence (ATI) service. Our Network Visibility products include our network packet brokers, bypass switches, virtual and physical taps and the related technical support, warranty and software maintenance services. The following table presents revenue by product line (in thousands):
			Year ended December 31,
			2013			2012			2011
	Network Test Solutions		$	376,297		$	376,673		$	311,370
	Network Visibility Solutions			90,959			36,761			-
	Total		$	467,256		$	413,434		$	311,370
	Significant Customers
	For the year ended December 31, 2013, two customers comprised more than 10% of total revenues. For the years ended December 31, 2012 and 2011, only one customer comprised more than 10% of total revenues as follows:
			Year Ended December 31,
			2013			2012			2011
	Customer A			10.6	%		13.5	%		14	%
	Customer B			14.3	%		*			*
	* Less than 10%
	As of December 31, 2013 and 2012, customers A and B did not have receivable balances comprised of more than 10% of total accounts receivable.
	International Data
	For the years ended December 31, 2013, 2012 and 2011, the percentage of total international revenues based on customer location consisted of the following:
			Year Ended December 31,
			2013			2012			2011
	International revenues			36.9	%		41.4	%		49.4	%
	For the years ended December 31, 2013, 2012 and 2011, the percentage of total revenues from product shipments to Japan was as follows:
			Year Ended December 31,
			2013			2012			2011
	Japan			*			10.6	%		*
	* Less than 10%
	As of December 31, 2013 and 2012, our property and equipment, net were geographically located as follows (in thousands):
			As of December 31,
			2013			2012
	United States		$	22,614		$	12,728
	India			5,300			6,706
	Romania			4,715			4,376
	Other			3,303			4,953
	Total		$	35,932		$	28,763

Note_6_Selected_Balance_Sheet_

Note 6 - Selected Balance Sheet Data	12 Months Ended
	Dec. 31, 2013
Disclosure Text Block Supplement [Abstract]	'
Supplemental Balance Sheet Disclosures [Text Block]	'
		6	Selected Balance Sheet Data
	Accounts Receivable, Net
	Accounts receivable, net consisted of the following (in thousands):
			December 31,			December 31,
			2013			2012
	Trade accounts receivable		$	110,430		$	104,959
	Allowance for doubtful accounts			(840	)		(1,436	)
	Total		$	109,590		$	103,523
	Activity in the allowance for doubtful accounts during the years presented is as follows (in thousands):
			December 31,			December 31,			December 31,
			2013			2012			2011
	Balance at beginning of year		$	1,436		$	1,747		$	1,073
	Additions: charged to costs and expenses			125			131			1,141
	Deductions: write-offs, net of recoveries			(721	)		(442	)		(467	)
	Balance at end of year		$	840		$	1,436		$	1,747
	Investments in Marketable Securities
	Investments in marketable securities as of December 31, 2013 consisted of the following (in thousands):
			Amortized			Gross Unrealized			Gross Unrealized			Fair
			Cost			Gains			Losses			Value
	Available-for-sale – short-term:
	U.S. Treasury, government and agency debt securities		$	31,717		$	26		$	(1	)	$	31,742
	Corporate debt securities			19,720			56			(11	)		19,765
	Total		$	51,437		$	82		$	(12	)	$	51,507
	Investments in marketable securities as of December 31, 2012 consisted of the following (in thousands):
			Amortized			Gross Unrealized			Gross Unrealized			Fair
			Cost			Gains			Losses			Value
	Available-for-sale – short-term:
	U.S. Treasury, government and agency debt securities		$	77,823		$	48		$	(1	)	$	77,870
	Corporate debt securities			47,933			1,068			(20	)		48,981
				125,756			1,116			(21	)		126,851
	Available-for-sale – long-term:
	Auction rate securities			820			2,301			(2	)		3,119
				820			2,301			(2	)		3,119
	Total		$	126,576		$	3,417		$	(23	)	$	129,970
	As of December 31, 2013 and 2012, the unrealized losses of our investment in available-for-sale securities that have been in a continuous unrealized loss position for more the 12 months or longer were insignificant. Unrealized losses related to these investments are due to interest rate fluctuations as opposed to changes in credit quality. In addition, we do not intend to sell and it is not more likely than not that we would be required to sell these investments before recovery of their amortized cost basis, which may be at maturity. As a result, there is no other-than-temporary impairment for these investments at December 31, 2013 and 2012.
	The amortized cost and fair value of our investments at December 31, 2013, by contractual years-to-maturity, are as follows (in thousands):
			Amortized
			Cost			Fair Value
	Due in less than 1 year		$	5,885		$	5,887
	Due within 1-2 years			30,793			30,837
	Due within 2-5 years			14,359			14,383
	Due after 5 years			400			400
	Total		$	51,437		$	51,507
	Inventories
	Inventories consisted of the following (in thousands):
			December 31,			December 31,
			2013			2012
	Raw materials		$	7,468		$	4,530
	Work in process			15,166			14,144
	Finished goods			24,502			18,546
	Total		$	47,136		$	37,220
	Property, Plant and Equipment, Net
	Property, plant and equipment, net consisted of the following (dollars in thousands):
						December 31,			December 31,
			Useful Life			2013			2012
			(in years)
	Computer equipment		3			$	13,790		$	11,931
	Computer software		5-Mar				16,085			13,676
	Demonstration equipment		2				25,934			25,422
	Development equipment		5				26,725			21,189
	Furniture and other equipment		5				18,413			15,062
	Building and leasehold improvements		Jan-40				19,419			11,842
	Total						120,366			99,122
Accumulated depreciation						(84,434	)		(70,359	)
Total					$	35,932		$	28,763
Accrued Expenses and Other
Accrued expenses and other consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
Compensation and related expenses		$	16,025		$	10,007
Vacation			9,310			7,552
Bonuses			6,789			12,211
Commissions			5,179			6,126
Professional fees			2,812			2,245
Other taxes			2,262			3,493
Income taxes			776			3,999
Other			10,595			6,892
Total		$	53,748		$	52,525

Note_7_Fair_Value_Measurements

Note 7 - Fair Value Measurements	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Fair Value Disclosures [Text Block]	'
		7	Fair Value Measurements
	Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in the principal or most advantageous market for an asset or liability in an orderly transaction between market participants at the measurement date.
	Fair Value Hierarchy
	The hierarchy below lists three levels of fair value based on the extent to which inputs used in measuring fair value are observable in the market. We categorize each of our fair value measurements in one of these three levels based on the lowest level input that is significant to the fair value measurement in its entirety. This hierarchy prioritizes the inputs into three broad levels as follows:
	Level 1.	Observable inputs such as quoted prices in active markets;
	Level 2.	Inputs, other than the quoted prices in active markets, that are observable either directly or indirectly; and
	Level 3.	Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions.
	Financial assets carried at fair value as of December 31, 2013 and 2012 are summarized below (in thousands):
			31-Dec-13										31-Dec-12
			Fair Value			Quoted			Significant		Significant		Fair Value		Quoted		Significant		Significant
						Prices in			Other		Unobservable				Prices in		Other		Unobservable
						Active			Observable		Inputs				Active		Observable		Inputs
						Markets for			Inputs		(Level 3)				Markets for		Inputs		(Level 3)
						Identical			(Level 2)						Identical		(Level 2)
						Assets									Assets
						(Level 1)									(Level 1)
	Cash equivalents:
	Money market funds		$	30		$	30		$	—	$	—	$	185	$	185	$	—	$	—
	Corporate debt securities			5,898			—			5,898		—		—		—		—		—
	Short-term investments:
	U.S. Treasury, government and agency debt securities			31,742			—			31,742		—		77,870		—		77,870		—
	Corporate debt securities			19,765			—			19,765		—		48,981		—		48,981		—
	Long-term investments:
	Auction rate securities			—			—			—		—		3,119		—		—		3,119
	Total financial assets		$	57,435		$	30		$	57,405	$	—	$	130,155	$	185	$	126,851	$	3,119
	Our cash and investment instruments are classified within Level 1 or Level 2 of the fair value hierarchy based on quoted prices, broker or dealer quotations, or alternative pricing sources with reasonable levels of price transparency.
	To estimate the fair value of our money market funds, U.S. treasury, government and agency debt securities and corporate debt securities, we use the estimated fair value per our investment brokerage/custodial statements. To the extent deemed necessary, we may also obtain non-binding market quotes to corroborate the estimated fair values reflected in our investment brokerage/custodial statements.
	During 2013, we sold auction rate securities (“ARS”) that were classified as Level 3 financial assets.  These ARS had a par value of $4.4 million and the sales resulted in a realized gains of $2.9 million (included within our Interest income and other, net line item on our consolidated statements of operations.) As of December 31, 2013, we did not hold any Level 3 assets.
	As of December 31, 2012, we held $3.1 million of auction rate securities which we classified as Level 3 because they are valued using valuation models with unobservable marketable inputs. Given the disruption in the auction process, there was no longer an actively quoted market price for these securities. Accordingly, we utilized models to estimate the fair values of these auction rate securities based on, certain unobservable inputs and other items, including: (i) the underlying structure of each security; (ii) the present value of future principal, interest and/or dividend payments discounted at the appropriate rate considering the market rate and conditions; (iii) consideration of the probabilities of default, auction failure, or repurchase at par for each period; and (iv) credit quality and estimates of the recovery rates in the event of default for each security.
	There were no transfers of assets between levels within the fair value hierarchy for the years ended December 31, 2013 and 2012.
	The following table summarizes the activity for the years ended December 31, 2013 and 2012 for our auction rate securities where fair value measurements are estimated utilizing Level 3 inputs (in thousands):
			Year Ended December 31,
			2013			2012
	Beginning balance		$	3,119		$	2,774
	Unrealized (gain) loss reclassified from/recorded in other comprehensive income			(2,299	)		513
	Realized gain recorded in earnings			2,870			32
	Sales			(3,690	)		(200	)
	Ending balance		$	—		$	3,119
	There were no unrealized losses recorded in earnings for Level 3 assets still held at December 31, 2013 and 2012.

Note_8_Goodwill_and_Other_Inta

Note 8 - Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'
Goodwill and Intangible Assets Disclosure [Text Block]	'
		8	Goodwill and Other Intangible Assets
	The following table presents the 2012 and 2013 activity for our goodwill (in thousands):
	Balance at January 1, 2012:		$	66,429
	Acquisition of Anue			91,376
	Acquisition of BreakingPoint			102,652
	Balance at December 31, 2012:		$	260,457
	Purchase price allocation adjustment for Anue			(367	)
	Purchase price allocation adjustment for BreakingPoint			(322	)
	Acquisition of Net Optics			112,064
	Balance at December 31, 2013		$	371,832
	We have not had any historical goodwill impairment charges.
	The following table presents our purchased intangible assets (in thousands) as of December 31, 2013:
			Weighted Average					Accumulated
			Useful Life			Gross		Amortization			Net
			(in years)
	Other intangible assets:
	Technology		5.5			$	184,377	$	(81,876	)	$	102,501
	Customer relationships		6				71,700		(28,911	)		42,789
	Service agreements		6.2				36,200		(9,398	)		26,802
	Non-compete agreements		4.1				9,000		(2,545	)		6,455
	Trademark		5.1				11,300		(3,066	)		8,234
	Other		3.7				4,211		(1,043	)		3,168
	Total					$	316,788	$	(126,839	)	$	189,949
	The following table presents our purchased intangible assets (in thousands) as of December 31, 2012:
			Weighted Average					Accumulated
			Useful Life			Gross		Amortization			Net
			(in years)
	Other intangible assets:
	Technology		5.4			$	141,215	$	(66,704	)	$	74,511
	Customer relationships		6				70,376		(18,289	)		52,087
	Service agreements		5.7				22,700		(5,272	)		17,428
	Non-compete agreements		4.2				5,700		(1,520	)		4,180
	Trademark		5.3				8,976		(2,333	)		6,643
	Other		3.8				3,416		(1,262	)		2,154
	Total					$	252,383	$	(95,380	)	$	157,003
	The estimated future amortization expense of purchased intangible assets as of December 31, 2013 is as follows (in thousands):
	2014		$	46,691
	2015			41,979
	2016			38,660
	2017			31,502
	2018			20,048
	Thereafter			11,069
	Total		$	189,949

Note_9_Income_Taxes

Note 9 - Income Taxes	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Income Tax Disclosure [Text Block]	'
		9	Income Taxes
	The components of income before income taxes were (in thousands):
			Year Ended December 31,
			2013			2012			2011
	U.S.		$	(5,501	)	$	20,418		$	4,179
	Foreign			16,303			(1,051	)		25,889
	Total		$	10,802		$	19,367		$	30,068
	The U.S. pre-tax income was significantly higher in 2012 due to intra-entity royalties generated in the U.S. related to the license of certain intellectual property rights of Anue and BreakingPoint.
	Income tax (benefit) expense consisted of the following (in thousands):
			Year Ended December 31,
			2013			2012			2011
	Current:
	Federal		$	2,920		$	9,145		$	(676	)
	State			756			2,387			(172	)
	Foreign			1,920			4,735			4,024
	Deferred:
	Federal			(9,286	)		(27,910	)		142
	State			(1,342	)		(10,932	)		30
	Foreign			3,964			(3,518	)		7
	Income tax (benefit) expense		$	(1,068	)	$	(26,093	)	$	3,355
	The net effective income tax rate differed from the federal statutory income tax rate as follows (dollars in thousands):
			2013			2012			2011
	Federal statutory expense		$	3,779		$	6,779		$	10,526
	State taxes, net of federal benefit			(836	)		(8,828	)		(58	)
	Research and development credits			(5,128	)		-			(1,659	)
	Domestic production deduction			(499	)		(826	)		-
	Stock-based compensation			1,750			1,738			1,082
	Foreign rate differential			(2,935	)		(4,386	)		(5,029	)
	Acquisition related costs			-			991			113
	Deemed Dividend			817
	Inter-company royalty			3,932			-			-
	Valuation allowance			1,111			(22,578	)		(749	)
	Release of uncertain tax positions			(2,106	)		-			-
	Other			(953	)		1,017			(871	)
	Income tax (benefit) expense			(1,068	)		(26,093	)		3,355
	Net effective income tax rate			(9.9	%)		(134.7	%)		11.2	%
	During 2013, the Company’s lower effective tax rate of (9.9%) when compared to the federal statutory income tax rate was mainly due to the R&D credits generated during the year, benefit recorded for the 2012 Federal R&D credit during the first quarter of 2013 as a result of the statutory extension of the credit during 2013, and the release of accrual for uncertain tax benefits. The Company’s lower effective tax rate in 2012 of (134.7%) when compared to the federal statutory income tax rate was mainly the result of the Company releasing valuation allowances against its U.S. deferred tax assets and tax benefits received as a result of the Company’s operations in lower tax foreign jurisdictions. The Company’s lower effective tax rate during 2011 when compared to the federal statutory income tax rate was mainly the result of the benefit for research and development credits and benefits received as a result of the Company’s operations in lower tax foreign jurisdictions.
	The primary components of temporary differences that gave rise to deferred taxes were as follows (in thousands):
			December 31,			December 31,
			2013			2012
	Deferred tax assets:
	Allowance for doubtful accounts		$	6		$	326
	Research and development credit carryforward			18,375			14,241
	Foreign tax credit carryforward			455			1,418
	Deferred revenue			2,942			2,879
	Stock-based compensation			9,698			7,350
	Inventory adjustments			6,238			5,139
	Net operating loss carryforward			5,585			10,543
	Unrealized loss on investments			-			3,631
	Realized loss on investments			3,211
	Accrued liabilities and other			4,782			4,472
	Depreciation & amortization			-			3,468
				51,292			53,467
	Valuation allowance			(4,144	)		(1,977	)
				47,148			51,490
	Deferred tax liabilities:
	Depreciation and amortization			(27,351	)		(45,635	)
	Intercompany royalty			(14,259	)		-
	Net deferred tax assets		$	5,538		$	5,855
	As of December 31, 2013 and 2012, current deferred tax assets totaled $13.7 million and $24.2 million, respectively and were included within the Prepaid Expenses & Other Current Assets line item in our consolidated balance sheets. As of December 31, 2013 and 2012, long-term deferred tax assets totaled $0 and $5.6 million, respectively, and were included as part of the Other Assets line item in our consolidated balance sheets.
	As of December 31, 2013 and 2012, long-term deferred tax liabilities totaled $8.1 million and $23.9 million, respectively, and were included within the Other Liabilities line item in our consolidated balance sheets.
	The realizability of deferred income tax assets is based on a more likely than not standard.  If it is determined that it is more likely than not that deferred income tax assets will not be realized, a valuation allowance must be established against the deferred income tax assets.
	Realization of our deferred tax assets is dependent primarily on the generation of future taxable income.  In considering the need for a valuation allowance we consider our historical, as well as, future projected taxable income along with other positive and negative evidence in assessing the realizability of our deferred tax assets.
During 2012, management reevaluated its need for a full valuation allowance previously set against its U.S. deferred tax assets and concluded it is more likely than not that all of its U.S. deferred tax assets, with the exception of its deferred tax assets for capital loss carryforwards, will be realized. Management’s conclusion to release the valuation allowance in 2012 was due to, among other reasons, (i) the three-year cumulative pre-tax accounting income realized in the U.S., (ii) the significant utilization of its net operating loss carryfowards and R&D credits during 2011 and 2012 and (iii) the significant net deferred tax liabilities recorded in connection with the 2012 acquisitions of Anue and BreakingPoint.
For the years ended December 31, 2013, 2012 and 2011, we recorded changes in our valuation allowance of $2.2 million, ($34.8) million, and $800,000, respectively.
As of December 31, 2013, we have gross federal and state research and development credit carryforwards of approximately $17.4 million and $17.8 million, respectively. The federal carryovers begin to expire 2021, while the state carryovers have an indefinite carryover period.
At December 31, 2013, we have gross federal and state net operating loss (“NOLs”) carryforwards of approximately $13.6 million and $4.9 million, respectively.  The federal NOLs expire beginning 2025, and the state NOLs begin to expire in 2016.  Section 382 of the Internal Revenue Code imposes an annual limitation on the utilization of net operating loss carryforwards related to acquired corporations based on a statutory rate of return (usually the “applicable federal funds rate” as defined in the Internal Revenue Code) and the value of the corporation at the time of a “change in ownership” as defined by Section 382.  We estimate that our 2013 limitation under Section 382 of the Internal Revenue Code is approximately $21.2 million.
Cumulative undistributed earnings of foreign subsidiaries for which no deferred income taxes have been provided approximated $91.8 million and $80.4 million at December 31, 2013 and 2012, respectively. No provision for U.S. income and foreign withholding taxes has been made for unrepatriated foreign earnings because it is expected that such earnings will be reinvested indefinitely outside of the U.S. Under current tax laws and regulations, if our cash, cash equivalents or investments associated with the subsidiaries’ undistributed earnings were distributed to the United States in the form of dividends or otherwise, it would be included in our U.S. taxable income and we would be subject to additional U.S. income taxes and foreign withholding taxes. Determination of the amount of unrecognized deferred income tax liability related to these earnings is not practicable.
At December 31, 2013, we had gross unrecognized tax benefits of approximately $16.8 million. Of this total, approximately $8.6 million (net of the federal benefit on state issues) would affect our effective tax rate if recognized.  We classify liabilities for unrecognized tax benefits for which we do not anticipate payment or receipt of cash within one year in noncurrent other liabilities.
We recognize interest and penalties related to uncertain tax positions in income tax expense.  During the years ended December 31, 2013, 2012, and 2011, we recognized approximately $49,000, $63,000, and $118,000, net of federal benefit, of interest within our statements of operations.  We had accrued interest, net of federal benefit, of $172,400 and $1.5 million as of December 31, 2013 and December 31, 2012 respectively.  We file income tax returns in the U.S. federal jurisdiction and in various state and foreign jurisdictions.  With few minor exceptions, we are no longer subject to U.S. federal, state and local, or non-U.S. income tax examinations by tax authorities in material jurisdictions for the tax years ended prior to 2007. The U.S. Internal Revenue Service is currently examining our 2010 and 2009 federal income tax returns. We are subject to income tax in many jurisdictions outside the U.S. Our operations in certain jurisdictions remain subject to examination, some of which are currently under audit by local tax authorities. The resolutions of these audits are not expected to be material to our financial statements.
A reconciliation of the beginning and ending amounts of gross unrecognized tax benefits is as follows (in thousands):
		2013			2012			2011
Unrecognized Tax Benefits - Beginning balance		$	14,454		$	13,232		$	12,303
Acquired unrecognized tax benefits			-			300			-
Gross increases – Tax positions taken in prior period			1,364			-			-
Gross decreases – Tax positions taken in prior period			(264	)		-			(140	)
Gross increases – Tax positions taken in current period			2,757			1,834			2,256
Lapse of statute of limitations			(1,545	)		(912	)		(1,187	)
Unrecognized Tax Benefits – ending balance		$	16,766		$	14,454		$	13,232

Note_10_Commitments_and_Contin

Note 10 - Commitments and Contingencies	12 Months Ended
	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies Disclosure [Text Block]	'
		10	Commitments and Contingencies
	We lease our facilities under non-cancelable operating leases for varying periods through May 2023, excluding options to renew. Certain leases require us to pay property taxes, insurance and routine maintenance, and include escalation clauses. The following are the future minimum commitments under these leases (in thousands):
			Year Ending December 31,*
			2014	$	11,261
			2015		10,499
			2016		7,955
			2017		5,557
			2018		4,790
			Thereafter		14,891
			Total	$	54,953
	*Minimum payments have not been reduced by minimum sublease rentals of $0.8 million due in the future under non-cancelable subleases.
	Rent expense for the years ended December 31, 2013, 2012 and 2011 was approximately $9.9 million, $8.9 million and $7.7 million, respectively.
	Securities Class Action
	On November 14, 2013, a purported securities class action complaint captioned Felix Santore v. Ixia, Victor Alston, Atul Bhatnagar, Thomas B. Miller, and Errol Ginsberg was filed against us and certain of our current and former officers and directors in the United States District Court for the Central District of California. The lawsuit purports to be a class action brought on behalf of purchasers of the Company’s securities during the period from April 10, 2010 through October 14, 2013. The complaint alleges that the defendants violated the Securities Exchange Act of 1934, as amended (the ”Exchange Act”), by making materially false and misleading statements concerning the Company’s recognition of revenues related to its warranty and software maintenance contracts and the academic credentials and employment history of the Company’s former President and Chief Executive Officer. The complaint also alleges that the defendants made false and misleading statements, and failed to make certain disclosures, regarding the Company’s business, operations and prospects, including regarding the financial statements and internal financial controls that were the subject of the April 2013 restatement of certain of our prior period financial statements and regarding the academic credentials and employment history of our former President and Chief Executive Officer. The complaint alleges that the Company lacked adequate internal financial controls and issued materially false and misleading financial statements for fiscal years ended December 31, 2010 and 2011, and the fiscal quarters ended March 31, 2011, June 30, 2011, September 30, 2011, March 31, 2012, June 30, 2012 and September 30, 2012. The complaint, which purports to assert claims for violations of Sections 10(b) and 20(a) of the Exchange Act and Rule 10b-5 promulgated thereunder, seeks, on behalf of the purported class, an unspecified amount of monetary damages, interest, fees and expenses of attorneys and experts, and other relief.
	On January 14, 2014, four sets of plaintiffs filed motions for appointment of counsel and appointment of lead plaintiff. Those sets of plaintiffs were: (i) Shawn McGrory, (ii) Rob Giampietro and Sunandra Krishna, (iii) Oklahoma Firefighters Pension & Retirement System and Oklahoma Law Enforcement Retirement System (collectively the “Oklahoma Group”), and (iv) District No. 9, I.A. of M.&A.W. Pension Trust. On March 24, 2014, the court issued a minute order appointing the Oklahoma Group as lead Plaintiff and appointing the Oklahoma Group’s selection of Grant & Eisenhofer P.A. as lead counsel.
	On April 11, 2014, the Company, along with the other named defendants and the Oklahoma Group, stipulated that the Oklahoma Group could have 30 days to file an amended complaint and that the defendants would have 30 days to move, answer or otherwise respond to the amended complaint after its filing. On May 5, 2014, the Court issued an order approving the stipulation. That order required that the Oklahoma Group’s first amended complaint be filed on or before June 11, 2014, and that the Company’s and the other defendants’ responsive motion or pleading be filed within 30 days thereafter.
	On June 11, 2014, the Oklahoma Group filed an amended complaint, asserting claims against the same defendants under the same legal theories as were set forth in the initial complaint. The amended complaint also contains allegations that certain of the individual defendants increased their trading in the Company’s stock during February, March and May of 2011 and during February and March of 2013, and that the defendants sought to inflate the Company’s reported deferred revenues during the relevant period. The amended complaint purports to be brought on behalf of purchasers of the Company’s securities from February 4, 2011 through April 3, 2014. Although the Company denies the material allegations of the complaint and intends to vigorously pursue its defenses, we are in the very early stages of this litigation, and are unable to predict the outcome of the case or to estimate the amount of or potential range of loss with respect to this complaint. However, the ultimate disposition of the case could have a material adverse impact on the Company’s financial condition, results of operations and cash flows.
	Shareholder Derivative Actions
	Two derivative actions by purported shareholders of the Company, which were recently consolidated into one action, are pending in the U.S. District Court for the Central District of California. The lawsuits are captioned (i) Erie County Employees' Retirement System, Derivatively on Behalf of Nominal Defendant IXIA v. Victor Alston, Errol Ginsberg, Laurent Asscher, Jonathan Fram, Gail Hamilton, Jon Rager, Atul Bhatnagar, and Thomas B. Miller, defendants, and Ixia, nominal defendant and (ii) Colleen Witmer, derivatively on behalf of Ixia v. Victor Alston, Atul Bhatnagar, Thomas B. Miller, Errol Ginsberg, Jonathan Fram, Laurent Asscher, Gail Hamilton, Jon F. Rager, Christopher Lee Williams, Alan Grahame, Raymond De Graaf, Walker H. Colston II, and Ronald W. Buckly, defendants, and Ixia, nominal defendant. The Erie County and Witmer cases were previously filed in the Superior Court of the State of California in January 2014 and February 2014, respectively, but were subsequently dismissed and thereafter refiled in the U.S. District Court in May 2014.
	Both plaintiffs have entered into a stipulation with the Company and the individual defendants providing for consolidation of the two actions. Under that stipulation, which has been approved by the court, the plaintiffs have until June 27, 2014 to file a consolidated complaint.
	The Erie County complaint alleges that the defendants breached their fiduciary duties to the Company by disseminating false and misleading statements concerning the Company’s internal controls and financial results during fiscal years 2010 through 2013, including issuing false and misleading statements in press releases, filings of Quarterly Reports on Form 10-Q and Annual Reports on Form 10-K, and conference calls. The complaint seeks an unspecified amount of monetary damages on behalf of the Company from the defendants. The Witmer complaint alleges against all or, depending on the allegation, certain defendants, breach of fiduciary duty, gross mismanagement, abuse of control, unjust enrichment and violations of California statutory provisions. The complaint includes allegations regarding our former President and Chief Executive Officer, Vic Alston, our financial statements and our internal financial controls that are similar to the allegations in the purported class action lawsuit described above. The complaint also includes allegations that in February 2013 and March 2013, certain defendants made “illicit insider sales” of the Company’s securities while allegedly in possession of material adverse non-public information. The complaint seeks an unspecified amount of monetary damages, modification of our corporate governance policies, disgorgement of profits, benefits and compensation, attorneys’ fees and costs, expenses incurred in prosecuting the action, and other relief.
	The Company, on whose behalf the derivative action claims have purportedly been brought, intends to move to dismiss the consolidated complaint (once it has been filed) on the grounds that the derivative plaintiffs did not file the claims in accordance with applicable laws governing the filing of derivative actions. As we are in the very early stages of this litigation, we are unable to predict the outcome of the litigation or to estimate the amount of or potential range of loss with respect to the consolidated complaint.
	Indemnifications
	In the normal course of business, we provide certain indemnifications, commitments and guarantees of varying scope to customers, including against claims of intellectual property infringement made by third parties arising from the use of our products. We also have certain obligations to indemnify our officers, directors and employees for certain events or occurrences while the officer, director or employee is or was serving at our request in such capacity. The duration of these indemnifications, commitments and guarantees varies and in certain cases, is indefinite. Many of these indemnifications, commitments and guarantees do not provide for any limitation of the maximum potential future payments that we could be obligated to make. However, our director and officer insurance policy may enable us to recover a portion of any future payments related to our officer, director or employee indemnifications. Historically, costs related to these indemnifications, commitments and guarantees have not been significant. With the exception of the product warranty accrual associated with our initial standard warranty (see Note 1 for additional information), no liabilities have been recorded for these indemnifications, commitments and guarantees.

Note_11_Shareholders_Equity

Note 11 - Shareholders' Equity	12 Months Ended
	Dec. 31, 2013
Stockholders' Equity Note [Abstract]	'
Stockholders' Equity Note Disclosure [Text Block]	'
		11	Shareholders’ Equity
	Stock Award Plans
	Amended and Restated 1997 Equity and Incentive Plan
	Our Amended and Restated 1997 Equity and Incentive Plan, as amended (the “1997 Plan”), provides for the issuance of share-based awards to our eligible employees and consultants. The share-based awards may include incentive stock options (“ISO”), non-statutory stock options, restricted stock units (“RSU”) or restricted stock awards. Options become exercisable over a vesting period as determined by the Board of Directors and expire over terms not exceeding 10 years from the date of grant. The exercise price for options granted under the 1997 Plan may not be granted at less than 100% of the fair market value of our Common Stock on the date of grant (110% for ISOs granted to an employee who owns more than 10% of the voting shares of the outstanding stock). Options generally vest over a four-year period. In the event the holder ceases to be employed by us, all unvested options are forfeited and all vested options may be exercised within a period of up to 30 days after the optionee’s termination for cause, up to 90 days after termination other than for cause or as a result of death or disability, or up to 180 days after termination as a result of disability or death. The 1997 Plan terminated in May 2008 and as such, no shares are available for future grant. As of December 31, 2013, 150,000 awards remained outstanding under the 1997 Plan.
	Second Amended and Restated Ixia 2008 Equity Incentive Plan
	Our Second Amended and Restated Ixia 2008 Equity Incentive Plan, as amended (the “2008 Plan” or the “Plan”), provides for the issuance of share-based awards to our eligible employees, directors and consultants. The share-based awards may include ISOs, non-statutory stock options, stock appreciation rights, RSU or restricted stock awards. Options become exercisable over a vesting period as determined by the Board of Directors and expire over terms not exceeding 7 years from the date of grant. The exercise price for options granted under the 2008 Plan may not be granted at less than 100% of the fair market value of our Common Stock on the date of grant (110% for ISOs granted to an employee who owns more than 10% of the voting shares of the outstanding stock). Options generally vest over a four-year period. In the event the holder ceases to be employed by us, all unvested options are forfeited and all vested options may be exercised within a period of up to 90 days after termination other than (i) for termination for cause for which the vested options are forfeited on the termination date or (ii) as a result of death or disability for which vested options may be exercised for up to 180 days after termination. The 2008 Plan will terminate in May 2018, unless terminated sooner by the Board of Directors.
	In June 2013, our shareholders approved the Second Amended and Restated Ixia 2008 Equity Incentive Plan, which resulted in amendments to our Amended and Restated Ixia 2008 Equity Incentive Plan, as amended, that include the following:
		●	Increase in Share Reserve. Increased the total number of shares of our common stock available for future grants by 9.8 million shares for a total of 29.0 million shares of our common stock authorized and reserved over the term of the Plan, of which 13.0 million shares were available for future grant as of December 31, 2013.
		●	Types of Awards. Added cash awards to the types of awards that may be granted under the Plan, including performance-based incentives that are intended to comply with Section 162(m) of the Internal Revenue Code of 1986, as amended (the “Code”).
		●	Award Limits. Added (i) a limit on the total number of shares (i.e., 1,000,000) subject to options and share appreciation rights granted to an eligible participant in any calendar year, (ii) with respect to performance-based awards that are intended to comply with the exception under Section 162(m) of the Code, limits on the total number of shares (i.e., 1,000,000) subject to RSUs and restricted stock awards that an individual may earn over a 12-month period and on the total dollar amount (i.e., $2,000,000) subject to cash awards that an individual may earn over a 12-month period, and (iii) a limit (i.e., $500,000) on the total dollar value of equity and cash awards that may be granted to a non-employee director in any calendar year.
	The Plan also provides for the following:
		●	Shares Not Available for Awards. None of the following will be added to the shares available for awards under the Plan: (i) shares tendered by a participant or withheld by us in payment of the exercise price of an option, or to satisfy any tax withholding obligation with respect to options, and (ii) shares reacquired by us on the open market using cash proceeds from the exercise of options.
		●	Acquisitions and Combinations. In connection with acquisitions and combinations by us, we may grant under the Plan awards in substitution or exchange for awards or rights to future awards previously granted by the acquired or combined company without reducing the shares available under the Plan. Any shares subject to but not issued under any such substitute awards would not become available for other awards granted under the Plan. Also, in the event that a company acquired by us or with which we combine has a pre-existing plan approved by its shareholders that was not adopted in contemplation of the acquisition or combination, available shares under that plan may be used for Plan awards without reducing the shares available under the Plan. Any such awards may only be made to persons who were not eligible to receive awards under the Plan prior to the acquisition or combination and may not be made after the date that awards could have been made under the terms of the pre-existing plan.
	Share Cancellation
	Certain of the Company’s performance-based equity awards include a forfeiture provision that provides for the forfeiture of the unvested portion of such equity awards in the event that the Company concludes that it is required to restate its previously issued financial statements to reflect a less favorable financial condition and/or less favorable results of operations. On April 2, 2013, the Company concluded to restate certain previously issued unaudited condensed consolidated financial statements, and, due to such forfeiture provisions, we have for accounting purposes deemed such equity awards to have been automatically forfeited and subsequently re-granted. As a result, we recorded a reversal of stock-based compensation expenses for the deemed cancellation of $4.0 million for the quarter ended June 30, 2013 and additional stock-based compensation expenses for the deemed re-grant of $3.7 million for the year ended December 31, 2013.
	The following table summarizes stock option activity for the year ended December 31, 2013 (in thousands, except per share and contractual life data):
			Number			Weighted			Weighted			Aggregate
						Average			Average			Intrinsic
						Exercise Price			Remaining
									Contractual
			of Options			Per Share			Life (in years)			Value
	Outstanding as of December 31, 2012			6,333		$	12.37			5.04		$	30,281
	Granted			1,161			16.31
	Exercised			(1,117	)		8.49
	Forfeited/canceled			(1,379	)		14.76
	Outstanding as of December 31, 2013			4,998		$	13.49			4.37		$	8,932
	Vested and expected to vest as of December 31, 2013			4,797		$	13.4			4.27		$	8,884
	Exercisable as of December 31, 2013			2,886		$	11.98			3.36		$	8,101
	The weighted average grant-date fair value of options granted for the years ended December 31, 2013, 2012 and 2011 was $6.92, $5.89 and $6.40 per share, respectively. The total intrinsic value of options exercised during the years ended December 31, 2013, 2012 and 2011 was $12.5 million, $14.6 million and $11.3 million, respectively. As of December 31, 2013, the remaining unrecognized compensation expense related to stock options is expected to be recognized over a weighted average period of 1.33 years.
	The following table summarizes RSU activity for the year ended December 31, 2013 (in thousands, except per share data):
			Number			Weighted Average
			of Awards			Grant Date Fair Value
						Per Share
	Outstanding as of December 31, 2012			1,692		$	12.69
	Awarded			1,039			17.06
	Vested			(687	)		11.33
	Forfeited/canceled			(294	)		14.97
	Outstanding as of December 31, 2013			1,750		$	15.43
	The weighted average fair value of RSUs vested during the year ended December 31, 2013 was $7.8 million. The total intrinsic value of RSUs vested during the year ended December 31, 2013 was $3.6 million. The weighted average remaining contractual life and expense recognition period of the outstanding RSUs as of December 31, 2013 was 1.44 years.
	Employee Stock Purchase Plan
	The employee stock purchase plan (the “2000 Purchase Plan”) was adopted and approved in September 2000. The 2000 Purchase Plan became effective upon the closing of our initial public offering in October 2000 and was amended in May 2003 and in April 2006. The 2000 Purchase Plan permits eligible employees to purchase Common Stock, subject to limitations as set forth in the 2000 Purchase Plan, through payroll deductions which may not exceed the lesser of 15% of an employee’s compensation or $21,250 per annum. The 2000 Purchase Plan is implemented in a series of consecutive, overlapping 24-month offering periods, with each offering period consisting of four six-month purchase periods. Offering periods begin on the first trading day on or after May 1 and November 1 of each year. During each 24-month offering period under the 2000 Purchase Plan, participants accumulate payroll deductions which on the last trading day of each six-month purchase period within the offering period are applied toward the purchase of shares of our Common Stock at a purchase price equal to 85% of the lower of (i) the fair market value of a share of our Common Stock as of the first trading day of the 24-month offering period and (ii) the fair market value of a share of Common Stock on the last trading day of the six-month purchase period. The 2000 Purchase Plan expired in September 2010. The last offering period under the 2000 Purchase Plan commenced on May 1, 2010 and ended on April 30, 2012. We had reserved a total of 4.5 million shares of Common Stock for issuance under the 2000 Purchase Plan, no shares are available for future issuance as of December 31, 2013. For the years ended, December 31, 2013, 2012 and 2011, zero, 105,000 and 375,000 shares, respectively, were issued under the 2000 Purchase Plan.
	During 2010, our shareholders approved the 2010 Employee Stock Purchase Plan (the “Purchase Plan”). The 2010 Purchase Plan replaced the 2000 Purchase Plan. The 2010 Purchase Plan is implemented in a series of consecutive, overlapping 24-month offering periods, with each offering period consisting of four six-month purchase periods. Offering periods begin on the first trading day on or after May 1 and November 1 of each year. The first 24-month offering period under the 2010 Purchase Plan began on November 1, 2010 and ended on October 31, 2012. The Purchase Plan provides the potential for an automatic annual increase of up to 500,000 in the number of shares reserved for issuance under the Purchase Plan on May 1 of each year during the ten-year term of the plan. The 2010 Purchase Plan will terminate in March 2020, unless it is earlier terminated by the Board of Directors.
	In November 2012, the number of shares authorized and reserved for issuance under the Purchase Plan was also increased by an additional 500,000 shares pursuant to the automatic annual increase provision of the Purchase Plan.
	In June 2013, our shareholders approved a 2,000,000-share increase in the number of shares of our common stock authorized and reserved for issuance under our Purchase Plan. During May 2013, the number of shares authorized and reserved for issuance under the Purchase Plan was also increased by an additional 500,000 shares pursuant to the automatic annual increase provision of the Purchase Plan.
	We have reserved a total of 3,800,000 shares of Common Stock for issuance under the Purchase Plan, of which 2,164,000 shares are available for future issuance for the existing and future offering periods. For the years ended December 31, 2013, 2012 and 2011, 918,000, 562,000 and 156,000 shares, respectively, were issued under the Purchase Plan.
	Stock-Based Compensation Expense
	The Black-Scholes option-pricing model is used to calculate the estimated fair value of share-based awards for options and RSUs on the respective dates of grant for accounting purposes using the following weighted average assumptions:
			Year Ended December 31,
			2013			2012			2011
	Expected lives (in years)			3.6			4.1			3.3
	Risk-free interest rates			0.6	%		0.6	%		1.3	%
	Dividend yield			0	%		0	%		0	%
	Expected volatility			48.9	%		51.8	%		50.5	%
	The Black-Scholes option-pricing model is used to calculate the estimated fair value of share-based awards for our Purchase Plan for accounting purposes using the following weighted average assumptions: expected lives of 1.25 years, risk-free interest rates of 0.9%, dividend yield of 0.0% and expected volatility of 48.4%.
	Expected lives (in years) - The expected life was determined by estimating the expected option life, using historical data.
	Risk-free interest rates - The risk-free interest rate for periods equal to the expected term of the option is based on the U.S. Treasury yield curve in effect at the time of grant.
	Dividend yield - We have never declared or paid cash dividends on our Common Stock and do not anticipate paying any dividends in the foreseeable future.
	Volatility - The stock volatility is determined based on the weighted average historical weekly price changes of our common stock over the expected option term.
	The aggregate balance of gross unrecognized stock-based compensation to be expensed in the years 2014 through 2017 related to all unvested share-based awards as of December 31, 2013 was approximately $26.3 million. There was no capitalized stock-based compensation expense for any of the periods presented.
	Accumulated Other Comprehensive Income
	The following table summarizes, as of each balance sheet date, the changes in our accumulated other comprehensive income, by component, net of income taxes (in thousands):
			Gains and Losses			Foreign Currency			Total
			on Available-for-			Items (a)
Sale Securities (a)
Beginning balance, December 31, 2012		$	2,070		$	219		$	2,289
Other comprehensive income before reclassifications			702			(638	)		64
Amounts reclassified from accumulated other comprehensive income (b)			(2,730	)		-			(2,730	)
Net current-period other comprehensive income			(2,028	)		(638	)		(2,666	)
Ending balance, December 31, 2013		$	42		$	(419	)	$	(377	)
(a)	All amounts are net-of-tax. Amounts in parentheses indicate reductions.
(b)	Amount represents gain on the sale of securities and is included as a component of Interest income and other, net in the consolidated statements of operations.
Other Comprehensive Income
We sold available-for-sale securities in the year ended December 31, 2013 which resulted in a gross reclassification from accumulated other comprehensive income for realized gains of $4.4 million, which was included within our Interest income and other, net line item on our consolidated statements of operations. This realized gain, along with the related tax impact for the year ended December 31, 2013 of $1.7 million was reclassified from Accumulated other comprehensive income.
Prior to the reclassification for the sale of available-for-sale securities, we had a net unrealized gain of $1.1 million for the year ended December 31, 2013. The tax impact for the unrealized gain was an expense of $447,000 for the year ended December 31, 2013.

Note_12_Retirement_Plan

Note 12 - Retirement Plan	12 Months Ended
	Dec. 31, 2013
Compensation and Retirement Disclosure [Abstract]	'
Pension and Other Postretirement Benefits Disclosure [Text Block]	'
		12	Retirement Plan
	We provide a 401(k) Retirement Plan (the “Plan”) to eligible employees who may authorize contributions up to IRS annual deferral limits to be invested in employee elected investment funds. As determined annually by the Board of Directors, we may contribute matching funds of 50% of the employee contributions up to $2,500. These matching contributions vest based on the employee’s years of service with us. For the years ended December 31, 2013, 2012, and 2011, we expensed and made contributions to the Plan in the amount of approximately $1.5 million, $870,000, and $845,000, respectively.

Note_13_Earnings_Per_Share

Note 13 - Earnings Per Share	12 Months Ended
	Dec. 31, 2013
Earnings per share: [Abstract]	'
Earnings Per Share [Text Block]	'
		13	Earnings Per Share
	The following table sets forth the computation of basic and diluted earnings per share for the periods indicated (in thousands, except per share data):
			Year Ended December 31,
			2013		2012		2011
	Basic Presentation
	Numerator for basic earnings per share:
	Net income		$	11,870	$	45,460	$	26,713
	Denominator for basic earnings per share:
	Weighted average common shares outstanding			75,757		72,183		69,231
	Basic earnings per share		$	0.16	$	0.63	$	0.39
	Diluted Presentation
	Numerator for diluted earnings per share:
	Net income		$	11,870	$	45,460	$	26,713
	Interest expense on convertible senior notes, net of tax			-		4,399		-
	Net income used for diluted earnings per share		$	11,870	$	49,859	$	26,713
	Denominator for dilutive earnings per share:
	Weighted average common shares outstanding			75,757		72,183		69,231
	Effect of dilutive securities:
	Stock options and other share-based awards			1,756		2,031		2,433
	Convertible senior notes			-		10,291		-
	Dilutive potential common shares			77,513		84,505		71,664
	Diluted earnings per share		$	0.15	$	0.59	$	0.37
	The diluted earnings per share computation for the year ended December 31, 2013, exclude (i) the weighted average number of shares underlying our outstanding convertible senior notes of 10.3 million shares, as they are considered anti-dilutive because the related interest expense on a per common share “if converted” basis exceeds basic earnings per share, and (ii) the weighted average number of shares underlying our employee stock options and other share-based awards of 2.2 million shares, which were anti-dilutive because, in general, the exercise price of these awards exceeded the average closing sales price per share of our common stock.
	The diluted earnings per share computation for the year ended December 31, 2012, exclude the weighted average number of shares underlying our employee stock options and other share-based awards of 2.3 million shares, which were anti-dilutive because, in general, the exercise price of these awards exceeded the average closing sales price per share of our common stock.
	The diluted earnings per share computation for the year ended December 31, 2011, excludes (i) the weighted average number of shares underlying our outstanding convertible senior notes of 10.3 million shares, as they are considered anti-dilutive because the related interest expense on a per common share “if converted” basis exceeds basic earnings per share, and (ii) the weighted average number of shares underlying our employee stock options and other share-based awards of 1.1 million shares, which were anti-dilutive because, in general, the exercise price of these awards exceeded the average closing price per share of our common stock during 2011.

Note_14_Quarterly_Financial_Su

Note 14 - Quarterly Financial Summary (Unaudited)	12 Months Ended
	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'
Quarterly Financial Information [Text Block]	'
		14	Quarterly Financial Summary (Unaudited)
			For the three months ended
			2013									2012
			Dec. 31(3)			Sep. 30		Jun. 30		Mar. 31		Dec. 31		Sep. 30(4)		Jun. 30(5)		Mar. 31
	(in thousands)
	Consolidated Statement of Operations Data:
	Total revenues		$	120,629		$	113,164	$	112,004	$	121,459	$	125,469	$	110,605	$	90,702	$	86,658
	Total cost of revenues (1)			36,300			30,997		30,829		30,926		32,064		30,241		20,585		19,593
	Gross profit			84,329			82,167		81,175		90,533		93,405		80,364		70,117		67,065
	(Loss) income before income taxes			(4,842	)		4,225		4,387		7,032		4,821		2,669		5,265		6,612
	Net (loss) income (2)			(3,069	)		4,102		3,017		7,820		3,653		10,944		25,696		5,167
	Earnings per share:
	Basic		$	(0.04	)	$	0.05	$	0.04	$	0.1	$	0.05	$	0.15	$	0.36	$	0.07
	Diluted		$	(0.04	)	$	0.05	$	0.04	$	0.1	$	0.05	$	0.14	$	0.32	$	0.07
	-1	For the quarters ended December 31, 2013, September 30, 2013, June 30, 2013, March 31, 2013, December 31, 2012, September 30, 2012, June 30, 2012, and March 31, 2012, total cost of revenues include charges related to amortization of intangible assets of $6.7 million, $6.4 million, $6.4 million, $6.5 million, $7.0 million, $7.0 million, $3.6 million, and $2.7 million, respectively.
	-2	For the quarters ended September 30, 2012 and June 30, 2012, we recorded partial release of our valuation allowance of $12.1 million and $22.7 million in the third and second quarters of 2012, respectively.
	-3	During the quarter ended December 31, 2013, we completed the acquisition of Net Optics for approximately $193.8 million.
	-4	During the quarter ended September 30, 2012, we completed the acquisition of BreakingPoint for approximately $163.7 million.
	-5	During the quarter ended June 30, 2012, we completed the acquisition of Anue for approximately $152.4 million

Accounting_Policies_by_Policy_

Accounting Policies, by Policy (Policies)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Basis of Accounting, Policy [Policy Text Block]	'
	Description of Business
	Ixia was incorporated on May 27, 1997 as a California corporation. We are a leading provider of converged Internet Protocol (IP) network test and network visibility solutions. Equipment manufacturers, service providers, enterprises, and government agencies use our solutions to design, verify, and monitor a broad range of Ethernet, Wi-Fi, 3G and 4G/LTE equipment and networks. Our product solutions consist of our hardware platforms, such as our chassis, interface cards and appliances, software application tools, and services, including our warranty and maintenance offerings and professional services.
	The Company is headquartered in Calabasas, California with operations across the U.S. and the rest of the world.  Our revenues are principally derived from shipments within the U.S. and to the EMEA and Asia Pacific regions.
Restatement [Policy Text Block]	'
	Basis of Presentation
	The accompanying consolidated financial statements for the years ended December 31, 2013, 2012 and 2011 have been prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP").
Use of Estimates, Policy [Policy Text Block]	'
	Use of Estimates
	In the normal course of preparing financial statements in conformity with accounting principles generally accepted in the United States, management is required to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Consolidation, Policy [Policy Text Block]	'
	Principles of Consolidation
	All subsidiaries are consolidated as they are 100% owned by us. All intercompany transactions and accounts are eliminated in consolidation.
Cash and Cash Equivalents, Policy [Policy Text Block]	'
	Cash and Cash Equivalents
	We consider all highly liquid investments with a maturity of three months or less at the date of purchase to be cash equivalents. Cash and cash equivalents are carried at cost, which approximates fair value. We generally place funds that are in excess of current needs in high credit quality instruments such as money market funds. There are no restrictions on the use of cash and cash equivalents.
Fair Value of Financial Instruments, Policy [Policy Text Block]	'
	Fair Value of Financial Instruments
	Our financial instruments, including cash and cash equivalents, short-term investments, accounts receivable and accounts payable are carried at cost, which approximates their fair values because of the short-term maturity of these instruments and the relative stability of interest rates. See Note 3 for information related to the fair value of our convertible senior notes.
	Fair value is defined as the exit price, or the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants as of the measurement date. There is an established hierarchy for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring the most observable inputs be used when available. Observable inputs are inputs market participants would use in valuing the asset or liability and are developed based on market data obtained from independent sources. Unobservable inputs are inputs that reflect the assumptions about the factors that market participants would use in valuing the asset or liability.
Derivatives, Policy [Policy Text Block]	'
	Foreign Currency Forward Contracts
	We utilize foreign currency forward contracts to hedge certain accounts receivable amounts that are denominated in Japanese Yen, Euros and British Pounds.  These contracts are cash flow hedges used to reduce the risk associated with exchange rate movements, as gains and losses on these contracts are intended to offset exchange losses and gains on underlying exposures.  Foreign currency contracts are typically short-term in duration ranging from one to four months. We do not enter into foreign exchange forward contracts for speculative or trading purposes. Foreign currency contracts are recorded at fair market values and the change in their fair value is recorded as gain or loss in the consolidated statements of operations as a component of Interest income and other, net.
	As of December 31, 2013, we held five open foreign currency forward contracts with a notional value of $7.0 million and a net fair value of approximately $54,000. As of December 31, 2012, we held 20 open foreign currency forward contracts with a notional value of $6.5 million and a net fair value of approximately $99,000. During 2013, net gains related to the change in fair value of such foreign currency forward contracts were $658,000. During 2012 and 2011, net losses related to the change in fair value of such foreign currency forward contracts were not significant. Net gains related to the change in fair value are reported as a component of Interest income and other, net in the consolidated statement of income. The fair value of foreign currency forward contracts are reported as a component of Prepaid and other current expenses in the consolidated balance sheet.
Marketable Securities, Policy [Policy Text Block]	'
	Investments in Marketable Securities
	We maintain a portfolio of cash equivalents and investments in a variety of fixed and variable rate securities, including U.S. government and federal agency securities, corporate debt securities, and money market funds. The primary objective of our investment activities is to maintain the safety of principal and preserve liquidity while maximizing yields without significantly increasing risk. We do not enter into investments for trading or speculative purposes. We determine the appropriate classification of investments in marketable securities at the time of purchase.  Accretion and amortization of purchase discounts and premiums are included in interest income and other, net. Available-for-sale securities are stated at fair value. The net unrealized gains or losses on available-for-sale securities are reported as a separate component of accumulated other comprehensive income or loss, net of tax. The specific identification method is used to compute realized gains and losses on our marketable securities. In 2013, 2012 and 2011, we had gross realized gains of $4.5 million, $1.3 million and $437,000, respectively. In 2013, 2012 and 2011, gross realized losses were not significant.
	We regularly review our investment portfolio to determine if any security is other-than-temporarily impaired, which would require us to record an impairment charge in the period any such determination is made. In making this judgment, we evaluate, among other things, the duration and extent to which the fair value of a security is less than its cost and our intent and ability to sell, or whether we will more likely than not be required to sell, the security before recovery of its amortized cost basis. We have evaluated our investments as of December 31, 2013 and have determined that no investments with unrealized losses are other-than-temporarily impaired. We do not intend to sell and it is not more likely than not that we would be required to sell these investments before recovery of their amortized cost basis, which may be at maturity.
	It is possible that we could recognize future impairment charges on our investment securities we currently own if future events, new information or the passage of time cause us to determine that a decline in our carrying value is other-than-temporary. We will continue to review and analyze these securities for triggering events each reporting period. See Note 6 for additional information.
Receivables, Policy [Policy Text Block]	'
	Accounts Receivable and Allowance for Doubtful Accounts
	Trade accounts receivable are recorded at the invoiced amount. The allowance for doubtful accounts is based on our best estimate of the amount of probable credit losses in existing accounts receivable.  We review the allowance for doubtful accounts and provisions are made upon a specific review of all significant past due receivables. For those receivables not specifically reviewed, provisions are provided at a general rate that considers historical write-off experience and other qualitative factors.   Account balances are charged off against the allowance when we believe it is probable the receivable will not be recovered.
Inventory, Policy [Policy Text Block]	'
	Inventories
	Inventories are goods held for sale in the normal course of business. Inventories are stated at the lower of cost (first-in, first-out) or market. The inventory balance consists of raw materials, work in process (“WIP”) and finished goods. Raw materials include low level components, many of which are purchased from vendors, WIP is partially assembled products and finished goods are products that are ready to be shipped to end customers. Consideration is given to inventory shipped and received near the end of a period and the transaction is recorded when transfer of title occurs. We evaluate inventory for excess and obsolescence and adjust to net realizable value based on inventory that is obsolete or in excess of current demand.
Property, Plant and Equipment, Policy [Policy Text Block]	'
	Property, Plant and Equipment
	Property, plant and equipment are stated at cost less accumulated depreciation. Depreciation of our computer software and equipment is computed using the straight-line method based upon the estimated useful lives of the applicable assets, ranging from three to five years. Building and leasehold improvements are amortized over the lesser of their estimated useful lives or the remaining lease term. Useful lives are evaluated periodically by management in order to determine recoverability in light of current technological conditions. Property, plant and equipment also includes the cost of our products used for research and development which are classified as development equipment and are depreciated over five years to research and development. We also capitalize and depreciate over a two-year period costs of our products used for sales and marketing activities, including product demonstrations for potential customers, which is included in Sales and marketing in the consolidated statements of operations. Repairs and maintenance are charged to expense as incurred while renewals and improvements are capitalized. Upon the sale or retirement of Property, plant and equipment, the accounts are relieved of the cost and the related Accumulated depreciation, with any resulting gain or loss included in the consolidated statements of operations.
Goodwill and Intangible Assets, Policy [Policy Text Block]	'
	Goodwill
	Goodwill is recorded as the difference, if any, between the aggregate consideration paid for an acquisition and the fair value of the acquired net tangible and intangible assets. Although goodwill is not amortized, we review our goodwill for impairment annually, or more frequently when events occur or circumstances indicate that the carrying amount of goodwill may not be recoverable. The impairment evaluation includes a comparison of the carrying value of the reporting unit to its fair value. If the reporting unit fair value exceeds its carrying value, then no impairment exists. If the fair value does not exceed its carrying value, then additional analysis is performed to determine the amount of any goodwill impairment. We completed our annual goodwill impairment test of our single reporting unit as of December 31, 2013 and determined that there was no impairment.
	Intangible Assets
	Intangible assets consist primarily of acquired intellectual property, such as technologies, customer relationships, and trade names.
	Acquired intangible assets with finite lives, including purchased technology, customer relationships, service agreements, trade names, and non-compete agreements are amortized over their estimated useful lives and reflected in the Amortization of intangible assets line item on our consolidated statements of operations.
	Intangible assets with finite lives are tested for impairment whenever events or circumstances indicate that the carrying amount of an asset (asset group) may not be recoverable. Circumstances which could trigger a review include, but are not limited to: significant adverse change in the extent or manner in which the intangible asset is being used, significant adverse changes in the business climate or legal factors; current period cash flow or operating losses combined with a history of losses or a forecast of continuing losses associated with the use of the asset; or current expectation that the asset will more likely than not be sold or disposed significantly before the end of its estimated useful life.
	An impairment loss is recognized when the carrying amount of an asset exceeds the estimated undiscounted cash flows used in determining the fair value of the asset. The amount of the impairment loss recorded is calculated by the excess of the asset’s carrying value over its fair value. Fair value is generally determined using a discounted cash flow analysis and may involve the use of significant estimates and assumptions, some of which may be based in part on historical experience, forecasted information and discount rates. No such impairment charges were recorded during the years ended December 31, 2013, 2012 and 2011.
Commitments and Contingencies, Policy [Policy Text Block]	'
	Litigation
	We are a defendant in one class action and in one consolidated shareholder derivative action. We accrue for losses when the loss is deemed probable and the liability can reasonably be estimated. Where a liability is probable and there is a range of estimated loss with no best estimate in the range, we record the minimum estimated liability related to the claim. As additional information becomes available, we assess the potential liability related to our pending litigation and revise our estimates. See Note 10 for additional information.
Standard Product Warranty, Policy [Policy Text Block]	'
	Product Warranty
	We generally provide an initial standard warranty (90-day or 12-month periods) on our hardware products after product shipment and accrue for estimated future warranty costs based on actual historical experience and other relevant data, as appropriate, at the time product revenue is recognized. All product warranty expenses associated with our initial standard warranty are reflected within Cost of revenues-products in the accompanying consolidated statements of operations. Accrued product warranty costs are included as a component of accrued expenses and other in the accompanying consolidated balance sheets.
	Activity in the product warranty liability account for the years presented is as follows (in thousands):
			December 31,			December 31,			December 31,
			2013			2012			2011
	Balance at beginning of year		$	665		$	703		$	697
	Current year provision			2,219			629			709
	Acquired liability (Net Optics acquisition)			117			—			—
	Expenditures			(2,355	)		(667	)		(703	)
	Balance at end of year		$	646		$	665		$	703
Revenue Recognition, Policy [Policy Text Block]	'
	Revenue Recognition
	In October 2009, the Financial Accounting Standards Board (“FASB”) issued authoritative guidance for the accounting of multiple-deliverable revenue arrangements, which establishes the accounting and reporting guidance for arrangements including multiple revenue-generating activities. This new authoritative guidance for arrangements with multiple deliverables requires that arrangement consideration be allocated at the inception of an arrangement to all deliverables using the relative selling price method. It also establishes a selling price hierarchy for determining the selling price of each deliverable. The new guidance also eliminates the residual method of allocation for multiple-deliverable revenue arrangements that are outside the scope of software revenue recognition guidance.
	In October 2009, the FASB also issued authoritative guidance for the accounting of certain revenue arrangements that include software elements, which changes the accounting model for revenue arrangements that include both tangible products and software elements that are “essential to the functionality” of the tangible products, and excludes these products from the software revenue accounting guidance.
	We adopted the new guidance on revenue recognition in the first quarter of 2011 on a prospective basis for applicable revenue arrangements originating or materially modified on or after January 1, 2011. The impact of the adoption of the new revenue recognition guidance is to accelerate the timing of revenue recognition principally related to partial shipments of hardware products at the end of accounting periods, which impact may vary from period to period. In periods prior to the adoption of the new guidance, the revenue related to partial shipments of our hardware products which were sold with software deliverables was deferred under the software revenue recognition guidance until the shipment or delivery of all items of a multiple element arrangement had occurred, other than the delivery of post contract customer support and maintenance (“PCS”). PCS was deferred based on established vendor specific objective evidence (“VSOE”) of selling price. As our revenues are generated from the sale of hardware and software products, and related services, a portion of our revenues will continue to be recognized under the software revenue recognition guidance (see below for additional information).
	Sales of our network test hardware products primarily consist of traffic generation and analysis hardware platforms containing multi-slot chassis and interface cards. Our primary network test hardware platform is enabled by our operating system software that is essential to the functionality of the hardware platform. Sales of our network visibility hardware products typically include an integrated, purpose-built hardware appliance with essential, proprietary software. Our software products consist of a comprehensive suite of technology-specific applications for certain of our network test hardware platforms. Our software products are typically installed on and work with these hardware products to further enhance the core functionality of the overall network test system, although some of our software products can be operated independently from our network test platforms.
	Our service revenues primarily consist of technical support, warranty and software maintenance services related to our network test and visibility hardware and software products. Many of our products include up to one year of these services with the initial product purchase and our customers may separately purchase extended services for annual or multi-year periods. Our technical support, warranty and software maintenance services include assistance with the set-up, configuration and operation of our products, repair or replacement of defective products, bug fixes, and unspecified when and if available software upgrades. For certain network test products, our technical support and software maintenance service revenues also include our Application and Threat Intelligence (ATI) service, which provides a comprehensive suite of application protocols, software updates and technical support. The ATI service provides full access to the latest security attacks and application updates for use in real-world test and assessment scenarios. Our customers may purchase the ATI service for annual or multi-year periods. Service revenues also include training and other professional services.
	As our systems typically include hardware and software products, and the related services, we recognize our revenue in accordance with authoritative guidance on both hardware and software revenue recognition. Furthermore, in accordance with the amended revenue recognition guidance, our hardware platform and certain other products that include both tangible products and software elements that function together to deliver the tangible product’s essential functionality have been scoped out of software revenue recognition guidance, and therefore these products are accounted for as hardware products for revenue recognition purposes.
	For our hardware and software products, and related services, we recognize revenue based on the following four criteria: whether (i) evidence of an arrangement exists, which is typically in the form of a customer purchase order; (ii) delivery has occurred (i.e., risks and rewards of ownership have passed to the customer); (iii) the sales price is fixed or determinable; and (iv) collectibility is deemed reasonably assured (or probable for software-related deliverables). Provided that the above criteria are met, revenue from hardware and software product sales is typically recognized upon shipment and service revenues are recognized as the services are provided or completed. Our service revenues from our initial and separately purchased technical support, warranty and software maintenance arrangements are recognized on a straight-line basis over the applicable contractual period.
	Our systems are generally fully functional at the time of shipment and do not require us to perform any significant production, modification, customization or installation after shipment. If our arrangements include acceptance provisions based on customer specified criteria for which we cannot reliably demonstrate that the delivered product meets all the specified criteria, revenue is deferred until the earlier of the receipt of written customer acceptance or the expiration of the acceptance period. In addition, our arrangements generally do not include any provisions for cancellation, termination or refunds.
Revenue Recognition, Multiple-deliverable Arrangements, Description [Policy Text Block]	'
	Multiple Element Arrangements and Allocation of Value
	Our arrangements with our customers to provide our systems typically include a combination of our hardware and software products, as well as the related technical support, warranty and software maintenance services of these products, and therefore are commonly referred to as multiple element arrangements. When sales arrangements involve hardware and software elements, we use a two-step process to allocate value to each element in the arrangement:
		-1	The total arrangement fee is allocated to the separate non-software deliverables (e.g., chassis, interface cards, and software PCS related to our operating system software that is essential to the functionality of our hardware platform) and the software-related deliverables as a group (e.g., application software and software PCS) based on a relative selling price (“RSP”) method applied to all elements in the arrangement using the selling price hierarchy in the amended revenue recognition guidance as discussed below, and
		-2	The value assigned to the software group for the software deliverables is then allocated to each software element based on the residual method, whereby value is allocated first to the undelivered elements, typically PCS, and the residual portion of the value is then allocated to the delivered elements (typically the software products) and recognized as revenue, provided all other revenue recognition criteria discussed above have been met. The fair value of an element must be based on vendor specific objective evidence (“VSOE”) of the selling price, which typically only exists for technical support, warranty and software maintenance services as discussed below.
	Under the RSP method, the selling price to be used in the allocation of the total arrangement fee to each of the elements, or deliverables, is based on a selling price hierarchy, where the selling price for each element is based on (i) VSOE, if available; (ii) third-party evidence (“TPE”), if available and VSOE is not available; or (iii) the best estimate of selling price (“BESP”), if neither VSOE nor TPE are available.
	We determine VSOE of fair value based on a bell-shaped curve approach, considering the actual sales prices charged to customers when the same element is sold separately, provided it is substantive. All of our products are sold as multiple element arrangement and not sold separately, as our products include an initial period (generally 90-day or 12-month periods) of free technical support, warranty and software maintenance services. Accordingly, we have not established VSOE for nearly all of our products. On a regular basis, we separately sell extended technical support, warranty and software maintenance services upon the expiration of the initial contractual periods included in an initial sales arrangement and have been able to establish VSOE for our technical support, warranty and software maintenance services.
	We generally are not able to determine TPE for our products or services because our products are not interchangeable with those of our competitors. Furthermore, we are unable to reliably determine competitive selling prices when the applicable competitive products are sold separately. As such, we use BESP for all of our products and services when allocating the total consideration of multiple element arrangements to each of the deliverables under step one of the allocation process described above except for our technical support, warranty and software maintenance services where we use VSOE. We determine BESP for a product or service by considering multiple factors including, analyzing historical sales price data for standalone and bundled arrangements, published price lists, geographies and customer types. Our estimate of BESP used in our allocation of arrangement consideration requires significant judgment and we review these estimated selling prices on a quarterly basis.
	The allocation of value to each deliverable in a multiple element arrangement is completed at the inception of an arrangement, which is typically the receipt of a customer purchase order. The allocated value of each non-software deliverable is then recognized as revenue when each element is delivered, provided all of the other revenue recognition criteria discussed above have been met. For software deliverables, the total software group allocation (or total arrangement consideration for customer orders that include only software products and related services) is allocated based on the residual method which requires that we first allocate value to the undelievered element at vendor specific objective evidence (“VSOE”) of the selling price of the undelivered element and the remaining portion of the arrangement fee is allocated to the delivered elements. As we do not sell our software products without technical support, warranty and software maintenance services, we are unable to establish VSOE for our software products, and therefore use the residual method under the software revenue recognition guidance to allocate the software group (or arrangement) value to each software deliverable. Under the residual method, the software group (or arrangement) value is allocated first to the undelivered elements, typically technical support, warranty and software maintenance services based on VSOE, and the residual portion of the value is then allocated to the delivered elements (typically the software products) and recognized as revenue, provided all other revenue recognition criteria discussed above have been met. If VSOE cannot be established for an undelivered element within the software group (or arrangement), we defer the entire value allocated to the software group (or arrangement) until the earlier of (i) delivery of all elements (other than technical support, warranty and software maintenance services, provided VSOE has been established) or (ii) establishment of VSOE of the undelivered element(s). If the only undelivered element(s) relates to a service for which VSOE has not been established, the entire allocated value of the software group (or arrangement) is recognized as revenue over the longer of the service or contractual period of the technical support, warranty and software maintenance services.
	Prior to the adoption of the amended revenue recognition guidance on January 1, 2011, our multiple element arrangements did not go through the two-step allocation process described above. The total arrangement consideration was assigned to each deliverable, including hardware products, based on VSOE in accordance with software revenue recognition guidance as described above. As a result, the substantial majority of our revenue was recognized under the residual method as VSOE was only established for our technical support, warranty and software maintenance services. This resulted in the deferral of revenue at the balance sheet date for partial shipments of multiple element arrangements. Under the amended revenue recognition guidance, we are able to allocate value to our hardware products, based on our best estimate of the selling price, and as a result are now typically able to recognize revenue for our hardware products when delivered, assuming all other revenue recognition criteria noted above have been met.
Revenue Recognition, Sales of Goods [Policy Text Block]	'
	Sales to Distributors
	We use distributors and resellers to complement our direct sales and marketing efforts in certain markets and/or for certain products. Due to the broad range of features and options available with our hardware and software products, distributors and resellers generally do not stock our products and typically place orders with us after receiving an order from an end customer. These distributors and resellers receive business terms of sale similar to those received by our other customers; and payment to Ixia is not contingent on sell-through to and receipt of payment from the end customer. As such, for sales to distributors and resellers, we recognize revenue when the risks and rewards of ownership have transferred to the distributor or reseller provided that the other revenue recognition criteria noted above have been met.
Cost of Sales, Policy [Policy Text Block]	'
	Cost of Revenues
	Our cost of revenues related to the sale of our hardware and software products includes materials, payments to third party contract manufacturers, royalties, and salaries and other expenses related to our manufacturing and supply operations personnel. We outsource the majority of our manufacturing operations, and we conduct supply chain management, quality assurance, documentation control, shipping and some final assembly and testing at our facilities in Calabasas, California, Austin, Texas and in Penang, Malaysia. Accordingly, a significant portion of our cost of revenues related to our products consists of payments to our contract manufacturers. Cost of revenues related to the provision of services includes salaries and other expenses associated with technical support services and the cost of extended warranty and maintenance services. Cost of revenues does not include the amortization of purchased technology related to our acquisitions of certain businesses, product lines and technologies of $26.0 million, $20.3 million and $10.8 million for the years ended December 31, 2013, 2012 and 2011, respectively, which are included within our Amortization of intangible assets line item on our consolidated statements of operations.
Research and Development Expense, Policy [Policy Text Block]	'
	Research and Development
	Research and development expenses consist primarily of salaries and other personnel costs related to the design, development, testing and enhancement of our products. Costs related to research and development activities, including those incurred to establish the technological feasibility of a software product, are expensed as incurred. If technological feasibility is established, all development costs incurred until general product release are subject to capitalization. To date, establishment of technological feasibility of our products and general release have substantially coincided. As a result, we have not capitalized any development costs.
Internal Use Software, Policy [Policy Text Block]	'
	Software Developed for Internal Use
	We capitalize costs of software, consulting services, hardware and payroll-related costs incurred to purchase or develop internal-use software in accordance with the authoritative guidance on accounting for the costs of computer software developed or obtained for internal use. Internally developed software includes enterprise-level business software that we are customizing to meet our specific operational needs. To date, internal costs incurred to purchase or develop software for internal use have not been significant. Internally developed software is amortized over five years. Purchased software is amortized over three years.
Advertising Costs, Policy [Policy Text Block]	'
	Advertising
	Advertising costs are expensed as incurred. Advertising costs included in sales and marketing were $2.9 million, $2.0 million and $1.1 million for the years ended December 31, 2013, 2012 and 2011, respectively.
Business Combinations Policy [Policy Text Block]	'
	Acquisition and Other Related Costs
	Acquisition and other related costs are expensed as incurred and consist primarily of transaction and integration related costs such as success-based banking fees, professional fees for legal, accounting, tax, due diligence, valuation and other related services, change in control payments, amortization of deferred compensation, consulting fees, required regulatory costs, certain employee, facility and infrastructure transition costs, and other related expenses. We expect our acquisition and other related expenses to fluctuate over time based on the timing of our acquisitions and related integration activities.
Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block]	'
	Stock-Based Compensation
	Share-based payments, including grants of stock options, restricted stock units and employee stock purchase rights, are required to be recognized in the financial statements based on the estimated fair values for accounting purposes on the grant date. We use the Black-Scholes option pricing model to estimate the fair value for accounting purposes of stock options and employee stock purchase rights. We use the grant date closing share sales price of a share of our common stock to estimate the fair value for accounting purposes of restricted stock units. The determination of the fair value of share-based awards utilizing the Black-Scholes model is affected by our stock price and a number of assumptions, including expected volatility, expected life and risk-free interest rate. The expected life and expected volatility are estimated based on historical data. The risk-free interest rate assumption is based on U.S. constant maturities over the expected life of the award. Stock-based compensation expense recognized in our consolidated financial statements is based on awards that are ultimately expected to vest. The amount of stock-based compensation expense is reduced for estimated forfeitures based on historical experience as well as future expectations. Forfeitures are required to be estimated at the time of grant and revised, if necessary, in subsequent periods if estimated and actual forfeitures differ from these initial estimates. We evaluate the assumptions used to value share-based awards on a periodic basis. We recognize stock-based compensation expense based on the graded, or accelerated multiple-option, approach over the vesting period.
	We have outstanding share-based awards that have performance-based vesting conditions. Awards with performance-based vesting conditions require the achievement of certain financial or other performance criteria as a condition to the vesting. We recognize the estimated fair value of performance-based awards, net of estimated forfeitures, as stock-based compensation expense over the performance period, using graded approach, based upon our determination of whether it is probable that the performance targets will be achieved. At each reporting period, we reassess the probability of achieving the performance criteria and the performance period required to meet those targets. Determining whether the performance criteria will be achieved involves judgment, and the estimate of stock-based compensation expense may be revised periodically based on changes in the probability of achieving the performance criteria. Revisions are reflected in the period in which the estimate is changed. If performance goals are not met, no stock-based compensation expense is recognized, and, to the extent stock-based compensation was previously recognized, such stock-based compensation is reversed.
Income Tax, Policy [Policy Text Block]	'
	Income Taxes
	We account for income taxes using the liability method. Deferred taxes are determined based on the differences between the financial statement and tax bases of assets and liabilities, using enacted tax rates in effect for the year in which the differences are expected to reverse. Valuation allowances are established when necessary to reduce deferred tax assets to the amounts expected more likely than not to be realized.
	We recognize, in our consolidated financial statements, the impact of tax positions that are more likely than not to be sustained upon examination based on the technical merits of the positions. See Note 9 for additional information.
Earnings Per Share, Policy [Policy Text Block]	'
	Earnings Per Share
	Basic earnings per share is computed using the weighted-average number of common shares outstanding during the period. Diluted earnings per share is computed using the weighted-average number of common shares and dilutive potential common shares outstanding during the period. Dilutive potential common shares primarily consist of shares underlying our convertible senior notes, employee stock options and restricted stock units. See Note 13 for additional information.
Foreign Currency Transactions and Translations Policy [Policy Text Block]	'
	Foreign Currency Translation and Transactions
	Assets and liabilities of non-U.S. subsidiaries that operate in a local currency environment are translated to U.S. Dollars at exchange rates in effect at the balance sheet date, with the resulting translation adjustments included as a separate component in accumulated other comprehensive income (loss). Income and expense accounts are translated at average exchange rates during the year. Where the U.S. Dollar is the functional currency, certain balance sheet and income statement accounts are remeasured at historical exchange rates and translation adjustments from the remeasurement of the local currency amounts to U.S. Dollars are included in interest income and other, net. During the years ended December 31, 2013, 2012 and 2011, we had net foreign currency income and (losses) of $267,000, ($519,000) and ($672,000), respectively, attributable to our foreign operations, which includes net gains and losses on forward contracts.
Comprehensive Income, Policy [Policy Text Block]	'
	Comprehensive Income
	Comprehensive income (loss) includes all changes in equity (net assets) during a period from non-owner sources. Accumulated other comprehensive income (loss) includes unrealized gains and losses on investments and foreign currency translation adjustments.
Segment Reporting, Policy [Policy Text Block]	'
	Segments
	Operating segments are defined as components of an enterprise engaged in business activities for which discrete financial information is available and regularly reviewed by the chief operating decision maker (“CODM”) of the enterprise to make decisions about resources to be allocated to the segment and to assess its performance. Our CODM is our Acting Chief Executive Officer who reviews our consolidated budgets and results for the purposes of allocating resources and evaluating financial performance.  Accordingly, we have determined that we operated within one business segment as of, and for the years ended, December 31, 2013, 2012 and 2011. See Note 5 for entity-wide disclosures about products and services, geographic areas and major customers.
New Accounting Pronouncements, Policy [Policy Text Block]	'
	Recent Accounting Pronouncements
	During May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers, which provides new guidance on the recognition of revenue and states that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The standard will be effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early adoption is not permitted. We have not evaluated the impact of the adoption of this accounting standard update on our consolidated financial position or results of operations.
	In July 2013, the Financial Accounting Standards Board (“FASB”) issued changes to the presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists. These changes require an entity to present an unrecognized tax benefit as a liability in the financial statements if (i) a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is not available at the reporting date under the tax law of the applicable jurisdiction to settle any additional income taxes that would result from the disallowance of a tax position, or (ii) the tax law of the applicable jurisdiction does not require the entity to use, and the entity does not intend to use, the deferred tax asset to settle any additional income taxes that would result from the disallowance of a tax position. Otherwise, an unrecognized tax benefit is required to be presented in the 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. Previously, there was diversity in practice as no explicit guidance existed. The effective date for this disclosure guidance is for fiscal years beginning after December 15, 2013 and is consistent with our current practices.
	In February 2013, FASB issued ASU No. 2013-02, Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income Under this standard, entities will be required to disclose additional information with respect to changes in accumulated other comprehensive income (AOCI) balances by component and significant items reclassified out of AOCI. Expanded disclosures for presentation of changes in AOCI involve disaggregating the total change of each component of other comprehensive income (for example, unrealized gains or losses on available for sale marketable securities) as well as presenting separately for each such component the portion of the change in AOCI related to (1) amounts reclassified into income and (2) current-period other comprehensive income. Additionally, for amounts reclassified into income, disclosure in one location would be required, based upon each specific AOCI component, of the amounts impacting individual income statement line items. Disclosure of the income statement line item impacts will be required only for components of AOCI reclassified into income in their entirety. Therefore, disclosure of the income statement line items affected by AOCI components such as net periodic benefit costs would not be included. The disclosures required with respect to income statement line item impacts would be made in either the notes to the consolidated financial statements or parenthetically on the face of the consolidated statements of operations. The effective date for this disclosure guidance was for fiscal years beginning after December 15, 2012. We adopted this new guidance prospectively in the quarter ended March 31, 2013 by including the appropriate disclosures. The implementation of this update did not impact our financial position, results of operations or cash flows as it was disclosure-only in nature.
	In July 2012, the FASB issued ASU No. 2012-02, Testing Indefinite-Lived Intangible Assets for Impairment. Under this standard, entities testing long-lived intangible assets for impairment now have an option of performing a qualitative assessment to determine whether further impairment testing is necessary. If an entity determines, on the basis of qualitative factors, that the fair value of the indefinite-lived intangible asset is more-likely-than-not less than the carrying amount, the existing quantitative impairment test is required. Otherwise, no further impairment testing is required. The effective date for this disclosure guidance is for fiscal years beginning after December 15, 2012, with early adoption permitted. We adopted this new guidance on January 1, 2013. The adoption of this new guidance did not have a significant impact on our consolidated financial position, results of operations and cash flows.

Note_1_Description_of_Business1

Note 1 - Description of Business, Basis of Presentation, Significant Accounting Policies and Recent Accounting Pronouncements (Tables)	12 Months Ended
	Dec. 31, 2013
Disclosure Text Block [Abstract]	'
Schedule of Product Warranty Liability [Table Text Block]	'
		December 31,			December 31,			December 31,
		2013			2012			2011
	Balance at beginning of year	$	665		$	703		$	697
	Current year provision		2,219			629			709
	Acquired liability (Net Optics acquisition)		117			—			—
	Expenditures		(2,355	)		(667	)		(703	)
	Balance at end of year	$	646		$	665		$	703

Note_2_Acquisitions_Tables

Note 2 - Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2013
Business Combinations [Abstract]	'
Schedule of Business Acquisitions, by Acquisition [Table Text Block]	'
	Cash and cash equivalents	$	235
	Accounts receivable		1,660
	Inventories		320
	Prepaid and other assets		268
	Identifiable intangible assets		8,800
	Goodwill		7,045
	Total assets acquired		18,328
	Accounts payable and accrued expenses		(2,020	)
	Deferred revenues		(500	)
	Net assets acquired	$	15,808
	Cash and cash equivalents	$	3,659
	Accounts receivable		12,016
	Inventories		4,380
	Prepaid and other assets		2,980
	Fixed assets		1,600
	Identifiable intangible assets		74,700
	Goodwill		91,008
	Total assets acquired		190,343
	Accounts payable, accrued expenses and other liabilities		(7,942	)
	Deferred revenues		(6,997	)
	Deferred tax liability, net		(22,964	)
	Net assets acquired	$	152,440
	Cash and cash equivalents	$	13,417
	Accounts receivable		4,610
	Inventories		3,156
	Prepaid and other assets		796
	Fixed assets		936
	Identifiable intangible assets		65,600
	Goodwill		102,330
	Total assets acquired		190,845
	Accounts payable, accrued expenses and other liabilities		(6,889	)
	Deferred revenues		(6,387	)
	Deferred tax liability, net		(13,882	)
	Net assets acquired	$	163,687
	Cash and cash equivalents	$	1,967
	Accounts receivable		9,253
	Inventories		6,543
	Prepaid and other assets		1,742
	Fixed assets,		2,976
	Identifiable intangible assets		72,858
	Goodwill		112,064
	Total assets acquired		207,403
	Accounts payable, accrued expenses and other liabilities		(8,441	)
	Deferred revenues		(5,170	)
	Net assets acquired	$	193,792
Business Acquisition, Pro Forma Information [Table Text Block]	'
		Year Ended
		December 31,
		2013			2012			2011
	Total revenues	$	516,767		$	514,075		$	382,192
	Net income		(2,097	)		(2,006	)		46,441

Note_4_Restructuring_Costs_Tab

Note 4 - Restructuring Costs (Tables)	12 Months Ended
	Dec. 31, 2013
Restructuring and Related Activities [Abstract]	'
Restructuring and Related Costs [Table Text Block]	'
		Total			BreakingPoint			Test
					Restructuring			Restructuring
	Accrual at December 31, 2011	$	-		$	-		$	-
	Charges		4,077			4,077			-
	Payments		(2,275	)		(2,275	)		-
	Non-cash items		(776	)		(776	)		-
	Accrual at December 31, 2012		1,026			1,026			-
	Charges		1,833			51			1,782
	Payments		(1,161	)		(474	)		(687	)
	Non-cash items		(191	)		(191	)		-
	Accrual at December 31, 2013	$	1,507		$	412		$	1,095

Note_5_Concentrations_Tables

Note 5 - Concentrations (Tables)	12 Months Ended
	Dec. 31, 2013
Note 5 - Concentrations (Tables) [Line Items]	'
Schedules of Concentration of Risk, by Risk Factor [Table Text Block]	'
		Year Ended December 31,
		2013			2012			2011
	Customer A		10.6	%		13.5	%		14	%
	Customer B		14.3	%		*			*
		Year Ended December 31,
		2013			2012			2011
	International revenues		36.9	%		41.4	%		49.4	%
		Year Ended December 31,
		2013			2012			2011
	Japan		*			10.6	%		*
Schedule of Disclosure on Geographic Areas, Long-Lived Assets in Individual Foreign Countries by Country [Table Text Block]	'
		As of December 31,
		2013			2012
	United States	$	22,614		$	12,728
	India		5,300			6,706
	Romania		4,715			4,376
	Other		3,303			4,953
	Total	$	35,932		$	28,763
Sales Revenue, Goods, Net [Member]	'
Note 5 - Concentrations (Tables) [Line Items]	'
Schedules of Concentration of Risk, by Risk Factor [Table Text Block]	'
		Year ended December 31,
		2013			2012			2011
	Network Test Solutions	$	376,297		$	376,673		$	311,370
	Network Visibility Solutions		90,959			36,761			-
	Total	$	467,256		$	413,434		$	311,370

Note_6_Selected_Balance_Sheet_1

Note 6 - Selected Balance Sheet Data (Tables)	12 Months Ended
	Dec. 31, 2013
Disclosure Text Block Supplement [Abstract]	'
Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]	'
		December 31,			December 31,
		2013			2012
	Trade accounts receivable	$	110,430		$	104,959
	Allowance for doubtful accounts		(840	)		(1,436	)
	Total	$	109,590		$	103,523
Allowance for Credit Losses on Financing Receivables [Table Text Block]	'
		December 31,			December 31,			December 31,
		2013			2012			2011
	Balance at beginning of year	$	1,436		$	1,747		$	1,073
	Additions: charged to costs and expenses		125			131			1,141
	Deductions: write-offs, net of recoveries		(721	)		(442	)		(467	)
	Balance at end of year	$	840		$	1,436		$	1,747
Available-for-sale Securities [Table Text Block]	'
		Amortized			Gross Unrealized			Gross Unrealized			Fair
		Cost			Gains			Losses			Value
	Available-for-sale – short-term:
	U.S. Treasury, government and agency debt securities	$	31,717		$	26		$	(1	)	$	31,742
	Corporate debt securities		19,720			56			(11	)		19,765
	Total	$	51,437		$	82		$	(12	)	$	51,507
		Amortized			Gross Unrealized			Gross Unrealized			Fair
		Cost			Gains			Losses			Value
	Available-for-sale – short-term:
	U.S. Treasury, government and agency debt securities	$	77,823		$	48		$	(1	)	$	77,870
	Corporate debt securities		47,933			1,068			(20	)		48,981
			125,756			1,116			(21	)		126,851
	Available-for-sale – long-term:
	Auction rate securities		820			2,301			(2	)		3,119
			820			2,301			(2	)		3,119
	Total	$	126,576		$	3,417		$	(23	)	$	129,970
Investments Classified by Contractual Maturity Date [Table Text Block]	'
		Amortized
		Cost			Fair Value
	Due in less than 1 year	$	5,885		$	5,887
	Due within 1-2 years		30,793			30,837
	Due within 2-5 years		14,359			14,383
	Due after 5 years		400			400
	Total	$	51,437		$	51,507
Schedule of Inventory, Current [Table Text Block]	'
		December 31,			December 31,
		2013			2012
	Raw materials	$	7,468		$	4,530
	Work in process		15,166			14,144
	Finished goods		24,502			18,546
	Total	$	47,136		$	37,220
Property, Plant and Equipment [Table Text Block]	'
					December 31,			December 31,
		Useful Life			2013			2012
		(in years)
	Computer equipment	3			$	13,790		$	11,931
	Computer software	5-Mar				16,085			13,676
	Demonstration equipment	2				25,934			25,422
	Development equipment	5				26,725			21,189
	Furniture and other equipment	5				18,413			15,062
	Building and leasehold improvements	Jan-40				19,419			11,842
	Total					120,366			99,122
	Accumulated depreciation					(84,434	)		(70,359	)
	Total				$	35,932		$	28,763
Schedule of Accrued Liabilities [Table Text Block]	'
		December 31,			December 31,
		2013			2012
	Compensation and related expenses	$	16,025		$	10,007
	Vacation		9,310			7,552
	Bonuses		6,789			12,211
	Commissions		5,179			6,126
	Professional fees		2,812			2,245
	Other taxes		2,262			3,493
	Income taxes		776			3,999
	Other		10,595			6,892
	Total	$	53,748		$	52,525

Note_7_Fair_Value_Measurements1

Note 7 - Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Fair Value, Assets Measured on Recurring Basis [Table Text Block]	'
		31-Dec-13										31-Dec-12
		Fair Value			Quoted			Significant		Significant		Fair Value		Quoted		Significant		Significant
					Prices in			Other		Unobservable				Prices in		Other		Unobservable
					Active			Observable		Inputs				Active		Observable		Inputs
					Markets for			Inputs		(Level 3)				Markets for		Inputs		(Level 3)
					Identical			(Level 2)						Identical		(Level 2)
					Assets									Assets
					(Level 1)									(Level 1)
	Cash equivalents:
	Money market funds	$	30		$	30		$	—	$	—	$	185	$	185	$	—	$	—
	Corporate debt securities		5,898			—			5,898		—		—		—		—		—
	Short-term investments:
	U.S. Treasury, government and agency debt securities		31,742			—			31,742		—		77,870		—		77,870		—
	Corporate debt securities		19,765			—			19,765		—		48,981		—		48,981		—
	Long-term investments:
	Auction rate securities		—			—			—		—		3,119		—		—		3,119
	Total financial assets	$	57,435		$	30		$	57,405	$	—	$	130,155	$	185	$	126,851	$	3,119
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]	'
		Year Ended December 31,
		2013			2012
	Beginning balance	$	3,119		$	2,774
	Unrealized (gain) loss reclassified from/recorded in other comprehensive income		(2,299	)		513
	Realized gain recorded in earnings		2,870			32
	Sales		(3,690	)		(200	)
	Ending balance	$	—		$	3,119

Note_8_Goodwill_and_Other_Inta1

Note 8 - Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'
Schedule of Goodwill [Table Text Block]	'
	Balance at January 1, 2012:	$	66,429
	Acquisition of Anue		91,376
	Acquisition of BreakingPoint		102,652
	Balance at December 31, 2012:	$	260,457
	Purchase price allocation adjustment for Anue		(367	)
	Purchase price allocation adjustment for BreakingPoint		(322	)
	Acquisition of Net Optics		112,064
	Balance at December 31, 2013	$	371,832
Schedule of Finite-Lived Intangible Assets [Table Text Block]	'
		Weighted Average					Accumulated
		Useful Life			Gross		Amortization			Net
		(in years)
	Other intangible assets:
	Technology	5.5			$	184,377	$	(81,876	)	$	102,501
	Customer relationships	6				71,700		(28,911	)		42,789
	Service agreements	6.2				36,200		(9,398	)		26,802
	Non-compete agreements	4.1				9,000		(2,545	)		6,455
	Trademark	5.1				11,300		(3,066	)		8,234
	Other	3.7				4,211		(1,043	)		3,168
	Total				$	316,788	$	(126,839	)	$	189,949
		Weighted Average					Accumulated
		Useful Life			Gross		Amortization			Net
		(in years)
	Other intangible assets:
	Technology	5.4			$	141,215	$	(66,704	)	$	74,511
	Customer relationships	6				70,376		(18,289	)		52,087
	Service agreements	5.7				22,700		(5,272	)		17,428
	Non-compete agreements	4.2				5,700		(1,520	)		4,180
	Trademark	5.3				8,976		(2,333	)		6,643
	Other	3.8				3,416		(1,262	)		2,154
	Total				$	252,383	$	(95,380	)	$	157,003
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]	'
	2014	$	46,691
	2015		41,979
	2016		38,660
	2017		31,502
	2018		20,048
	Thereafter		11,069
	Total	$	189,949

Note_9_Income_Taxes_Tables

Note 9 - Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]	'
		Year Ended December 31,
		2013			2012			2011
	U.S.	$	(5,501	)	$	20,418		$	4,179
	Foreign		16,303			(1,051	)		25,889
	Total	$	10,802		$	19,367		$	30,068
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]	'
		Year Ended December 31,
		2013			2012			2011
	Current:
	Federal	$	2,920		$	9,145		$	(676	)
	State		756			2,387			(172	)
	Foreign		1,920			4,735			4,024
	Deferred:
	Federal		(9,286	)		(27,910	)		142
	State		(1,342	)		(10,932	)		30
	Foreign		3,964			(3,518	)		7
	Income tax (benefit) expense	$	(1,068	)	$	(26,093	)	$	3,355
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	'
		2013			2012			2011
	Federal statutory expense	$	3,779		$	6,779		$	10,526
	State taxes, net of federal benefit		(836	)		(8,828	)		(58	)
	Research and development credits		(5,128	)		-			(1,659	)
	Domestic production deduction		(499	)		(826	)		-
	Stock-based compensation		1,750			1,738			1,082
	Foreign rate differential		(2,935	)		(4,386	)		(5,029	)
	Acquisition related costs		-			991			113
	Deemed Dividend		817
	Inter-company royalty		3,932			-			-
	Valuation allowance		1,111			(22,578	)		(749	)
	Release of uncertain tax positions		(2,106	)		-			-
	Other		(953	)		1,017			(871	)
	Income tax (benefit) expense		(1,068	)		(26,093	)		3,355
	Net effective income tax rate		(9.9	%)		(134.7	%)		11.2	%
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]	'
		December 31,			December 31,
		2013			2012
	Deferred tax assets:
	Allowance for doubtful accounts	$	6		$	326
	Research and development credit carryforward		18,375			14,241
	Foreign tax credit carryforward		455			1,418
	Deferred revenue		2,942			2,879
	Stock-based compensation		9,698			7,350
	Inventory adjustments		6,238			5,139
	Net operating loss carryforward		5,585			10,543
	Unrealized loss on investments		-			3,631
	Realized loss on investments		3,211
	Accrued liabilities and other		4,782			4,472
	Depreciation & amortization		-			3,468
			51,292			53,467
	Valuation allowance		(4,144	)		(1,977	)
			47,148			51,490
	Deferred tax liabilities:
	Depreciation and amortization		(27,351	)		(45,635	)
	Intercompany royalty		(14,259	)		-
	Net deferred tax assets	$	5,538		$	5,855
Summary of Positions for which Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Table Text Block]	'
		2013			2012			2011
	Unrecognized Tax Benefits - Beginning balance	$	14,454		$	13,232		$	12,303
	Acquired unrecognized tax benefits		-			300			-
	Gross increases – Tax positions taken in prior period		1,364			-			-
	Gross decreases – Tax positions taken in prior period		(264	)		-			(140	)
	Gross increases – Tax positions taken in current period		2,757			1,834			2,256
	Lapse of statute of limitations		(1,545	)		(912	)		(1,187	)
	Unrecognized Tax Benefits – ending balance	$	16,766		$	14,454		$	13,232

Note_10_Commitments_and_Contin1

Note 10 - Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]	'
Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block]	'
		Year Ending December 31,*
		2014	$	11,261
		2015		10,499
		2016		7,955
		2017		5,557
		2018		4,790
		Thereafter		14,891
		Total	$	54,953

Note_11_Shareholders_Equity_Ta

Note 11 - Shareholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2013
Stockholders' Equity Note [Abstract]	'
Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]	'
		Number			Weighted			Weighted			Aggregate
					Average			Average			Intrinsic
					Exercise Price			Remaining
								Contractual
		of Options			Per Share			Life (in years)			Value
	Outstanding as of December 31, 2012		6,333		$	12.37			5.04		$	30,281
	Granted		1,161			16.31
	Exercised		(1,117	)		8.49
	Forfeited/canceled		(1,379	)		14.76
	Outstanding as of December 31, 2013		4,998		$	13.49			4.37		$	8,932
	Vested and expected to vest as of December 31, 2013		4,797		$	13.4			4.27		$	8,884
	Exercisable as of December 31, 2013		2,886		$	11.98			3.36		$	8,101
Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block]	'
		Number			Weighted Average
		of Awards			Grant Date Fair Value
					Per Share
	Outstanding as of December 31, 2012		1,692		$	12.69
	Awarded		1,039			17.06
	Vested		(687	)		11.33
	Forfeited/canceled		(294	)		14.97
	Outstanding as of December 31, 2013		1,750		$	15.43
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	'
		Year Ended December 31,
		2013			2012			2011
	Expected lives (in years)		3.6			4.1			3.3
	Risk-free interest rates		0.6	%		0.6	%		1.3	%
	Dividend yield		0	%		0	%		0	%
	Expected volatility		48.9	%		51.8	%		50.5	%
Comprehensive Income (Loss) [Table Text Block]	'
		Gains and Losses			Foreign Currency			Total
		on Available-for-			Items (a)
		Sale Securities (a)
	Beginning balance, December 31, 2012	$	2,070		$	219		$	2,289
	Other comprehensive income before reclassifications		702			(638	)		64
	Amounts reclassified from accumulated other comprehensive income (b)		(2,730	)		-			(2,730	)
	Net current-period other comprehensive income		(2,028	)		(638	)		(2,666	)
	Ending balance, December 31, 2013	$	42		$	(419	)	$	(377	)

Note_13_Earnings_Per_Share_Tab

Note 13 - Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2013
Earnings per share: [Abstract]	'
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	'
		Year Ended December 31,
		2013		2012		2011
	Basic Presentation
	Numerator for basic earnings per share:
	Net income	$	11,870	$	45,460	$	26,713
	Denominator for basic earnings per share:
	Weighted average common shares outstanding		75,757		72,183		69,231
	Basic earnings per share	$	0.16	$	0.63	$	0.39
	Diluted Presentation
	Numerator for diluted earnings per share:
	Net income	$	11,870	$	45,460	$	26,713
	Interest expense on convertible senior notes, net of tax		-		4,399		-
	Net income used for diluted earnings per share	$	11,870	$	49,859	$	26,713
	Denominator for dilutive earnings per share:
	Weighted average common shares outstanding		75,757		72,183		69,231
	Effect of dilutive securities:
	Stock options and other share-based awards		1,756		2,031		2,433
	Convertible senior notes		-		10,291		-
	Dilutive potential common shares		77,513		84,505		71,664
	Diluted earnings per share	$	0.15	$	0.59	$	0.37

Note_14_Quarterly_Financial_Su1

Note 14 - Quarterly Financial Summary (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'
Schedule of Quarterly Financial Information [Table Text Block]	'
		For the three months ended
		2013									2012
		Dec. 31(3)			Sep. 30		Jun. 30		Mar. 31		Dec. 31		Sep. 30(4)		Jun. 30(5)		Mar. 31
	(in thousands)
	Consolidated Statement of Operations Data:
	Total revenues	$	120,629		$	113,164	$	112,004	$	121,459	$	125,469	$	110,605	$	90,702	$	86,658
	Total cost of revenues (1)		36,300			30,997		30,829		30,926		32,064		30,241		20,585		19,593
	Gross profit		84,329			82,167		81,175		90,533		93,405		80,364		70,117		67,065
	(Loss) income before income taxes		(4,842	)		4,225		4,387		7,032		4,821		2,669		5,265		6,612
	Net (loss) income (2)		(3,069	)		4,102		3,017		7,820		3,653		10,944		25,696		5,167
	Earnings per share:
	Basic	$	(0.04	)	$	0.05	$	0.04	$	0.1	$	0.05	$	0.15	$	0.36	$	0.07
	Diluted	$	(0.04	)	$	0.05	$	0.04	$	0.1	$	0.05	$	0.14	$	0.32	$	0.07

Note_1_Description_of_Business2

Note 1 - Description of Business, Basis of Presentation, Significant Accounting Policies and Recent Accounting Pronouncements (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Note 1 - Description of Business, Basis of Presentation, Significant Accounting Policies and Recent Accounting Pronouncements (Details) [Line Items]	'	'	'
Investment Foreign Currency, Contract, Amount Sold	$7,000,000	$6,500,000	'
Foreign Currency Derivatives at Fair Value, Net	54,000	99,000	'
Gain (Loss) on Foreign Currency Fair Value Hedge Derivatives	658,000	'	'
Available-for-sale Securities, Gross Realized Gain (Loss)	4,469,000	1,300,000	437,000
Amortization of Intangible Assets	40,805,000	30,018,000	15,980,000
Advertising Expense	2,900,000	2,000,000	1,100,000
Net Foreign Currency Transaction and Translation Loss	-267,000	519,000	672,000
Number of Operating Segments	1	'	'
Development Equipment [Member]	'	'	'
Note 1 - Description of Business, Basis of Presentation, Significant Accounting Policies and Recent Accounting Pronouncements (Details) [Line Items]	'	'	'
Property, Plant and Equipment, Useful Life	'5 years	'	'
Products Used for Sales and Marketing [Member]	'	'	'
Note 1 - Description of Business, Basis of Presentation, Significant Accounting Policies and Recent Accounting Pronouncements (Details) [Line Items]	'	'	'
Property, Plant and Equipment, Useful Life	'2 years	'	'
Software Development [Member]	'	'	'
Note 1 - Description of Business, Basis of Presentation, Significant Accounting Policies and Recent Accounting Pronouncements (Details) [Line Items]	'	'	'
Property, Plant and Equipment, Useful Life	'5 years	'	'
Software Development [Member] | Minimum [Member]	'	'	'
Note 1 - Description of Business, Basis of Presentation, Significant Accounting Policies and Recent Accounting Pronouncements (Details) [Line Items]	'	'	'
Property, Plant and Equipment, Useful Life	'3 years	'	'
Software Development [Member] | Maximum [Member]	'	'	'
Note 1 - Description of Business, Basis of Presentation, Significant Accounting Policies and Recent Accounting Pronouncements (Details) [Line Items]	'	'	'
Property, Plant and Equipment, Useful Life	'5 years	'	'
Software and Software Development Costs [Member]	'	'	'
Note 1 - Description of Business, Basis of Presentation, Significant Accounting Policies and Recent Accounting Pronouncements (Details) [Line Items]	'	'	'
Property, Plant and Equipment, Useful Life	'3 years	'	'
Acquired Technology [Member]	'	'	'
Note 1 - Description of Business, Basis of Presentation, Significant Accounting Policies and Recent Accounting Pronouncements (Details) [Line Items]	'	'	'
Amortization of Intangible Assets	$26,000,000	$20,300,000	$10,800,000
Minimum [Member]	'	'	'
Note 1 - Description of Business, Basis of Presentation, Significant Accounting Policies and Recent Accounting Pronouncements (Details) [Line Items]	'	'	'
Property, Plant and Equipment, Useful Life	'3 years	'	'
Maximum [Member]	'	'	'
Note 1 - Description of Business, Basis of Presentation, Significant Accounting Policies and Recent Accounting Pronouncements (Details) [Line Items]	'	'	'
Property, Plant and Equipment, Useful Life	'5 years	'	'

Note_1_Description_of_Business3

Note 1 - Description of Business, Basis of Presentation, Significant Accounting Policies and Recent Accounting Pronouncements (Details) - Product Warranty Liability (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Product Warranty Liability [Abstract]	'	'	'
Balance at beginning of year	$665	$703	$697
Current year provision	2,219	629	709
Acquired liability (Net Optics acquisition)	117	'	'
Expenditures	-2,355	-667	-703
Balance at end of year	$646	$665	$703

Note_2_Acquisitions_Details

Note 2 - Acquisitions (Details) (USD $)

3 Months Ended

12 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

12 Months Ended

1 Months Ended

3 Months Ended

12 Months Ended

1 Months Ended

3 Months Ended

12 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2012

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2012

Mar. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2011

Dec. 31, 2011

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2011

Jul. 18, 2011

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Jun. 30, 2012

Dec. 31, 2013

Dec. 31, 2012

Jun. 01, 2013

Jun. 01, 2012

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Aug. 24, 2012

Sep. 30, 2012

Dec. 31, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 05, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

VeriWave, Inc. [Member]

VeriWave, Inc. [Member]

VeriWave, Inc. [Member]

VeriWave, Inc. [Member]

VeriWave, Inc. [Member]

VeriWave, Inc. [Member]

Anue Systems, Inc [Member]

Anue Systems, Inc [Member]

Anue Systems, Inc [Member]

Anue Systems, Inc [Member]

Anue Systems, Inc [Member]

Anue Systems, Inc [Member]

Anue Systems, Inc [Member]

Anue Systems, Inc [Member]

Anue Systems, Inc [Member]

Anue Systems, Inc [Member]

BreakingPoint Systems, Inc. [Member]

BreakingPoint Systems, Inc. [Member]

BreakingPoint Systems, Inc. [Member]

BreakingPoint Systems, Inc. [Member]

BreakingPoint Systems, Inc. [Member]

BreakingPoint Systems, Inc. [Member]

BreakingPoint Systems, Inc. [Member]

BreakingPoint Systems, Inc. [Member]

BreakingPoint Systems, Inc. [Member]

BreakingPoint Systems, Inc. [Member]

BreakingPoint Systems, Inc. [Member]

Net Optics, Inc. [Member]

Net Optics, Inc. [Member]

Net Optics, Inc. [Member]

Net Optics, Inc. [Member]

Net Optics, Inc. [Member]

Net Optics, Inc. [Member]

Net Optics, Inc. [Member]

Net Optics, Inc. [Member]

Net Optics, Inc. [Member]

Customer Relationships [Member]

Customer Relationships [Member]

Other Intangible Assets [Member]

Other Intangible Assets [Member]

Noncompete Agreements [Member]

Noncompete Agreements [Member]

Service Agreements [Member]

Service Agreements [Member]

Minimum [Member]

Minimum [Member]

Minimum [Member]

Minimum [Member]

Maximum [Member]

Maximum [Member]

Maximum [Member]

Maximum [Member]

Acquired Technology [Member]

Customer Relationships [Member]

Other Intangible Assets [Member]

Acquired Technology [Member]

Customer Relationships [Member]

Other Intangible Assets [Member]

Trade Names [Member]

Noncompete Agreements [Member]

Acquired Technology [Member]

Customer Relationships [Member]

Other Intangible Assets [Member]

Trade Names [Member]

Noncompete Agreements [Member]

Service Agreements [Member]

Acquired Technology [Member]

Customer Relationships [Member]

Other Intangible Assets [Member]

Trade Names [Member]

Noncompete Agreements [Member]

VeriWave, Inc. [Member]

Anue Systems, Inc [Member]

BreakingPoint Systems, Inc. [Member]

Net Optics, Inc. [Member]

VeriWave, Inc. [Member]

Anue Systems, Inc [Member]

BreakingPoint Systems, Inc. [Member]

Net Optics, Inc. [Member]

Note 2 - Acquisitions (Details) [Line Items]

'

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'

'

'

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'

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Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net

'

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'

'

'

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'

'

'

'

'

'

'

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'

'

'

$15,808,000

'

'

'

'

'

'

'

'

$152,400,000

$152,440,000

'

'

'

'

'

'

$163,687,000

'

'

'

$163,700,000

'

'

'

'

'

$193,800,000

$193,800,000

$193,800,000

$193,792,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Business Combination, Acquisition Related Costs

'

'

'

'

'

'

'

'

'

6,920,000

11,861,000

1,100,000

'

'

'

2,100,000

972,000

'

'

'

'

'

'

'

269,000

4,900,000

'

'

'

'

'

'

'

'

'

'

1,100,000

6,900,000

'

'

'

'

'

'

4,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Finite-lived Intangible Assets Acquired

'

'

'

'

'

'

'

'

'

'

'

'

4,300,000

3,500,000

1,000,000

'

8,800,000

'

45,000,000

21,900,000

1,700,000

4,000,000

2,100,000

'

74,700,000

'

'

'

22,700,000

20,600,000

600,000

2,900,000

2,200,000

16,600,000

'

'

65,600,000

'

'

50,000,000

15,800,000

400,000

3,000,000

3,700,000

72,900,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Acquired Finite-lived Intangible Assets, Weighted Average Useful Life

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

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'

'

'

'

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'

'

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'

'

'

'

'

'

'

'

'

'

'

'

'

'6 years

'6 years

'3 years 255 days

'3 years 292 days

'4 years 36 days

'4 years 73 days

'6 years 73 days

'5 years 255 days

'6 months

'6 months

'14 days

'4 months

'6 years

'6 years

'6 years

'7 years

Accounts Receivable, Net, Current

109,590,000

'

'

'

103,523,000

'

'

'

'

109,590,000

103,523,000

'

'

'

'

'

'

'

'

'

'

'

'

'

173,000

'

'

'

'

'

'

'

'

'

'

'

-58,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Accounts Payable and Other Accrued Liabilities

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

-172,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Valuation Allowance, Deferred Tax Asset, Change in Amount

'

'

'

'

'

-12,100,000

-22,700,000

'

-22,700,000

2,200,000

-34,800,000

800,000

'

'

'

'

'

'

'

'

'

'

'

'

-22,000

'

'

'

'

'

'

'

'

'

'

'

-264,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Goodwill

371,832,000

'

'

'

260,457,000

'

'

'

'

371,832,000

260,457,000

66,429,000

'

'

'

'

'

7,045,000

'

'

'

'

'

'

-367,000

'

'

91,008,000

'

'

'

'

'

'

102,330,000

'

-322,000

'

'

'

'

'

'

'

'

'

'

112,064,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Business Acquisition, Potential Cash Payment

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

3,200,000

'

-2,100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Business Acquisition, Potential Cash Payment, Payment Period

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'2 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Payments to Acquire Businesses, Gross

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

152,400,000

'

'

'

'

'

'

'

'

'

'

'

163,700,000

2,400,000

'

'

'

'

'

'

'

'

193,800,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

4,800,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,900,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Revenues

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

54,900,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest

($4,842,000)

[1]

$4,225,000

$4,387,000

$7,032,000

$4,821,000

$2,669,000

[2]

$5,265,000

[3]

$6,612,000

'

$10,802,000

$19,367,000

$30,068,000

'

'

'

'

'

'

'

'

'

'

'

'

$7,900,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

[1]

During the quarter ended December 31, 2013, we completed the acquisition of Net Optics for approximately $193.8 million.

[2]

During the quarter ended September 30, 2012, we completed the acquisition of BreakingPoint for approximately $163.7 million.

[3]

During the quarter ended June 30, 2012, we completed the acquisition of Anue for approximately $152.4 million

Note_2_Acquisitions_Details_Al

Note 2 - Acquisitions (Details) - Allocation of Purchase Price (USD $)

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Jul. 18, 2011

Dec. 31, 2013

Jun. 01, 2013

Jun. 01, 2012

Dec. 31, 2013

Sep. 30, 2013

Aug. 24, 2012

Dec. 31, 2013

Dec. 05, 2013

VeriWave, Inc. [Member]

Anue Systems, Inc [Member]

Anue Systems, Inc [Member]

Anue Systems, Inc [Member]

BreakingPoint Systems, Inc. [Member]

BreakingPoint Systems, Inc. [Member]

BreakingPoint Systems, Inc. [Member]

Net Optics, Inc. [Member]

Net Optics, Inc. [Member]

Business Acquisition [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

Cash and cash equivalents

'

'

'

$235,000

'

'

$3,659,000

'

'

$13,417,000

'

$1,967,000

Accounts receivable

'

'

'

1,660,000

'

'

12,016,000

'

'

4,610,000

'

9,253,000

Inventories

'

'

'

320,000

'

'

4,380,000

'

'

3,156,000

'

6,543,000

Prepaid and other assets

'

'

'

268,000

'

'

2,980,000

'

'

796,000

'

1,742,000

Fixed assets, net

'

'

'

'

'

'

1,600,000

'

'

936,000

'

2,976,000

Identifiable intangible assets

'

'

'

8,800,000

'

'

74,700,000

'

'

65,600,000

'

72,858,000

Goodwill

371,832,000

260,457,000

66,429,000

7,045,000

-367,000

'

91,008,000

-322,000

'

102,330,000

'

112,064,000

Total assets acquired

'

'

'

18,328,000

'

'

190,343,000

'

'

190,845,000

'

207,403,000

Accounts payable, accrued expenses and other liabilities

'

'

'

-2,020,000

'

'

-7,942,000

'

'

-6,889,000

'

-8,441,000

Deferred revenues

'

'

'

-500,000

'

'

-6,997,000

'

'

-6,387,000

'

-5,170,000

Deferred tax liability, net

'

'

'

'

'

'

-22,964,000

'

'

-13,882,000

'

'

Net assets acquired

'

'

'

$15,808,000

'

$152,400,000

$152,440,000

'

$163,700,000

$163,687,000

$193,800,000

$193,792,000

Note_2_Acquisitions_Details_Un

Note 2 - Acquisitions (Details) - Unaudited Proforma Total Revenues and Net Loss of the Combined Entities (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Unaudited Proforma Total Revenues and Net Loss of the Combined Entities [Abstract]	'	'	'
Total revenues	$516,767	$514,075	$382,192
Net income	($2,097)	($2,006)	$46,441

Note_3_Long_Term_Debt_Details

Note 3 - Long Term Debt (Details) (USD $)	1 Months Ended	0 Months Ended	12 Months Ended
	Dec. 21, 2012	Dec. 07, 2010	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 21, 2013
Note 3 - Long Term Debt (Details) [Line Items]	'	'	'	'	'	'
Convertible Notes Payable, Noncurrent	'	$200,000,000	$200,000,000	$200,000,000	'	'
Interest Paid	'	'	6,000,000	6,000,000	6,133,000	'
Deferred Finance Costs, Gross	'	6,000,000	'	'	'	'
Debt Instrument, Convertible, Term of Notes	'	'5 years	'	'	'	'
Amortization of Financing Costs	'	'	1,200,000	1,200,000	1,200,000	'
Debt Instrument, Convertible, Conversion Ratio	'	51.4536	'	'	'	'
Debt Instrument, Convertible, Principal Amount	'	1,000	'	'	'	'
Debt Instrument, Convertible, Conversion Price (in Dollars per share)	'	$19.43	'	'	'	'
Debt Instrument, Convertible, Required Repurchase Price	'	100.00%	'	'	'	'
Minimum Aggregate Principal Amount of Outstanding Notes Threshold	'	25.00%	'	'	'	'
Convertible Debt, Fair Value Disclosures	'	'	215,700,000	230,100,000	'	'
Line of Credit Facility, Maximum Borrowing Capacity	'	'	'	'	'	150,000,000
Debt Covenants, Available Liquidity	'	'	'	'	'	25,000,000
Potential Maximum Borrowing Capacity of Credit Facility	50,000,000	'	'	'	'	'
Debt Instrument, Description of Variable Rate Basis	'	'	'Borrowings under the Credit Facility bear interest at either (i) the Base Rate, which is equal to the highest of (a) the administrative agent's prime rate, (b) the federal funds rate plus 0.50% and (c) the London Interbank Offered Rate ("LIBOR") for a one-month interest period plus 1.00% or (ii) LIBOR plus the applicable margin. The applicable margin ranges are from 1.75% to 2.25% for LIBOR loans and 0.75% to 1.25% for Base Rate loans, and depends on the Company's total leverage ratio (as defined in the Credit Facility Agreement). Interest is payable quarterly. No amounts were drawn down under this Credit Facility as of December 31, 2013.	'	'	'
LIBOR Interest Period	'	'	'1 month	'	'	'
Minimum Pledge of Outstanding Securities of Directly-Owned Foreign Subsidiaries	'	'	65.00%	'	'	'
Term of Credit Facility	'4 years	'	'	'	'	'
Debt Covenants, Interest Coverage Ratio	3.5	'	'	'	'	'
Through June 30, 2014 [Member]	'	'	'	'	'	'
Note 3 - Long Term Debt (Details) [Line Items]	'	'	'	'	'	'
Debt Covenants, Maximum Leverage Ratio	3.5	'	'	'	'	'
After June 30, 2014 [Member]	'	'	'	'	'	'
Note 3 - Long Term Debt (Details) [Line Items]	'	'	'	'	'	'
Debt Covenants, Maximum Leverage Ratio	3	'	'	'	'	'
Default Rate [Member]	'	'	'	'	'	'
Note 3 - Long Term Debt (Details) [Line Items]	'	'	'	'	'	'
Debt Instrument, Basis Spread on Variable Rate	'	'	0.50%	'	'	'
Base Rate Loans - Federal Funds Rate [Member]	'	'	'	'	'	'
Note 3 - Long Term Debt (Details) [Line Items]	'	'	'	'	'	'
Debt Instrument, Basis Spread on Variable Rate	'	'	0.50%	'	'	'
One-month LIBOR [Member]	'	'	'	'	'	'
Note 3 - Long Term Debt (Details) [Line Items]	'	'	'	'	'	'
Debt Instrument, Basis Spread on Variable Rate	'	'	1.00%	'	'	'
Convertible Senior Notes [Member]	'	'	'	'	'	'
Note 3 - Long Term Debt (Details) [Line Items]	'	'	'	'	'	'
Debt Instrument, Interest Rate, Stated Percentage	'	3.00%	'	'	'	'
Standby Letters of Credit [Member]	'	'	'	'	'	'
Note 3 - Long Term Debt (Details) [Line Items]	'	'	'	'	'	'
Line of Credit Facility, Maximum Borrowing Capacity	25,000,000	'	'	'	'	'
Swingline Facility [Member]	'	'	'	'	'	'
Note 3 - Long Term Debt (Details) [Line Items]	'	'	'	'	'	'
Line of Credit Facility, Maximum Borrowing Capacity	15,000,000	'	'	'	'	'
Line of Credit [Member]	'	'	'	'	'	'
Note 3 - Long Term Debt (Details) [Line Items]	'	'	'	'	'	'
Deferred Finance Costs, Gross	'	'	947,000	'	'	'
Revolving Credit Facility [Member]	'	'	'	'	'	'
Note 3 - Long Term Debt (Details) [Line Items]	'	'	'	'	'	'
Amortization of Financing Costs	'	'	270,000	'	'	'
Minimum [Member] | London Interbank Offered Rate (LIBOR) [Member]	'	'	'	'	'	'
Note 3 - Long Term Debt (Details) [Line Items]	'	'	'	'	'	'
Debt Instrument, Basis Spread on Variable Rate	'	'	1.75%	'	'	'
Minimum [Member] | Base Rate [Member]	'	'	'	'	'	'
Note 3 - Long Term Debt (Details) [Line Items]	'	'	'	'	'	'
Debt Instrument, Basis Spread on Variable Rate	'	'	0.75%	'	'	'
Maximum [Member] | London Interbank Offered Rate (LIBOR) [Member]	'	'	'	'	'	'
Note 3 - Long Term Debt (Details) [Line Items]	'	'	'	'	'	'
Debt Instrument, Basis Spread on Variable Rate	'	'	2.25%	'	'	'
Maximum [Member] | Base Rate [Member]	'	'	'	'	'	'
Note 3 - Long Term Debt (Details) [Line Items]	'	'	'	'	'	'
Debt Instrument, Basis Spread on Variable Rate	'	'	1.25%	'	'	'
Maximum [Member] | Revolving Credit Facility [Member]	'	'	'	'	'	'
Note 3 - Long Term Debt (Details) [Line Items]	'	'	'	'	'	'
Line of Credit Facility, Commitment Fee Amount	'	'	$450,000	'	'	'
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	'	'	0.30%	'	'	'

Note_4_Restructuring_Costs_Det

Note 4 - Restructuring Costs (Details) (USD $)	12 Months Ended		3 Months Ended	12 Months Ended	3 Months Ended	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2013
			BreakingPoint Systems, Inc. [Member]	BreakingPoint Systems, Inc. [Member]	Test Restructuring [Member]	Test Restructuring [Member]
Note 4 - Restructuring Costs (Details) [Line Items]	'	'	'	'	'	'
Restructuring and Related Cost, Number of Positions Eliminated	'	'	29	'	120	'
Restructuring Charges	$1,840,000	$4,077,000	'	$4,100,000	'	$1,782,000
Severance Costs	'	'	'	2,700,000	'	'
Business Exit Costs	'	'	'	1,400,000	'	'
Accrued Liabilities and Other Liabilities	$53,748,000	$52,525,000	'	$1,000,000	$1,100,000	$1,100,000
Percentage of Workforce Reduced	'	'	'	'	6.50%	'

Note_4_Restructuring_Costs_Det1

Note 4 - Restructuring Costs (Details) - Activity Related to Restructuring Plans (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Restructuring Cost and Reserve [Line Items]	'	'
Accrual balance	$1,507	$1,026
Charges	1,840	4,077
Payments	-1,161	-2,275
Non-cash items	-191	-776
BreakingPoint Restructuring [Member]	'	'
Restructuring Cost and Reserve [Line Items]	'	'
Accrual balance	412	1,026
Charges	51	4,077
Payments	-474	-2,275
Non-cash items	-191	-776
Test Restructuring [Member]	'	'
Restructuring Cost and Reserve [Line Items]	'	'
Accrual balance	1,095	'
Charges	1,782	'
Payments	($687)	'

Note_5_Concentrations_Details_

Note 5 - Concentrations (Details) - Revenue Concentrations (USD $)

3 Months Ended

12 Months Ended

In Thousands, unless otherwise specified

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2012

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Concentration Risk [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Total revenues

$120,629

[1]

$113,164

$112,004

$121,459

$125,469

$110,605

[2]

$90,702

[3]

$86,658

$467,256

$413,434

$311,370

Network Test Solutions [Member]

'

'

'

'

'

'

'

'

'

'

'

Concentration Risk [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Total revenues

'

'

'

'

'

'

'

'

376,297

376,673

311,370

Network Visibility Solutions [Member]

'

'

'

'

'

'

'

'

'

'

'

Concentration Risk [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Total revenues

'

'

'

'

'

'

'

'

$90,959

$36,761

'

[1]

During the quarter ended December 31, 2013, we completed the acquisition of Net Optics for approximately $193.8 million.

[2]

During the quarter ended September 30, 2012, we completed the acquisition of BreakingPoint for approximately $163.7 million.

[3]

During the quarter ended June 30, 2012, we completed the acquisition of Anue for approximately $152.4 million

Note_5_Concentrations_Details_1

Note 5 - Concentrations (Details) - Revenue Percentages (Sales Revenue, Net [Member])	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Customer A [Member] | Customer Concentration Risk [Member]	'		'		'
Concentration Risk [Line Items]	'		'		'
Revenue percentage	10.60%		13.50%		14.00%
Customer B [Member] | Customer Concentration Risk [Member]	'		'		'
Concentration Risk [Line Items]	'		'		'
Revenue percentage	14.30%		'	[1]	'	[1]
Geographic Concentration Risk [Member] | International [Member]	'		'		'
Concentration Risk [Line Items]	'		'		'
Revenue percentage	36.90%		41.40%		49.40%
Geographic Concentration Risk [Member] | JAPAN	'		'		'
Concentration Risk [Line Items]	'		'		'
Revenue percentage	'	[1]	10.60%		'	[1]
[1]	Less than 10%

Note_5_Concentrations_Details_2

Note 5 - Concentrations (Details) - Geographical Location of Property and Equitpment (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Note 5 - Concentrations (Details) - Geographical Location of Property and Equitpment [Line Items]	'	'
Property, plant and equipment, net	$35,932	$28,763
UNITED STATES	'	'
Note 5 - Concentrations (Details) - Geographical Location of Property and Equitpment [Line Items]	'	'
Property, plant and equipment, net	22,614	12,728
INDIA	'	'
Note 5 - Concentrations (Details) - Geographical Location of Property and Equitpment [Line Items]	'	'
Property, plant and equipment, net	5,300	6,706
ROMANIA	'	'
Note 5 - Concentrations (Details) - Geographical Location of Property and Equitpment [Line Items]	'	'
Property, plant and equipment, net	4,715	4,376
Other Countries [Member]	'	'
Note 5 - Concentrations (Details) - Geographical Location of Property and Equitpment [Line Items]	'	'
Property, plant and equipment, net	$3,303	$4,953

Note_6_Selected_Balance_Sheet_2

Note 6 - Selected Balance Sheet Data (Details) - Accounts Receivable, Net (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
In Thousands, unless otherwise specified
Accounts Receivable, Net [Abstract]	'	'	'	'
Trade accounts receivable	$110,430	$104,959	'	'
Allowance for doubtful accounts	-840	-1,436	-1,747	-1,073
Total	$109,590	$103,523	'	'

Note_6_Selected_Balance_Sheet_3

Note 6 - Selected Balance Sheet Data (Details) - Activity in the Allowance for Doubtful Accounts (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Activity in the Allowance for Doubtful Accounts [Abstract]	'	'	'
Balance at beginning of year	$1,436	$1,747	$1,073
Additions: charged to costs and expenses	125	131	1,141
Deductions: write-offs, net of recoveries	-721	-442	-467
Balance at end of year	$840	$1,436	$1,747

Note_6_Selected_Balance_Sheet_4

Note 6 - Selected Balance Sheet Data (Details) - Investments in Marketable Securities (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Available-for-sale – short-term:	'	'
Amortized Cost	$51,437	$126,576
Gross Unrealized Gains	82	3,417
Gross Unrealized Losses	-12	-23
Fair Value	51,507	129,970
Short-term Investments [Member] | US Government Agencies Debt Securities [Member]	'	'
Available-for-sale – short-term:	'	'
Amortized Cost	31,717	77,823
Gross Unrealized Gains	26	48
Gross Unrealized Losses	-1	-1
Fair Value	31,742	77,870
Short-term Investments [Member] | Corporate Debt Securities [Member]	'	'
Available-for-sale – short-term:	'	'
Amortized Cost	19,720	47,933
Gross Unrealized Gains	56	1,068
Gross Unrealized Losses	-11	-20
Fair Value	19,765	48,981
Short-term Investments [Member]	'	'
Available-for-sale – short-term:	'	'
Amortized Cost	'	125,756
Gross Unrealized Gains	'	1,116
Gross Unrealized Losses	'	-21
Fair Value	'	126,851
Other Long-term Investments [Member] | Auction Rate Securities [Member]	'	'
Available-for-sale – short-term:	'	'
Amortized Cost	'	820
Gross Unrealized Gains	'	2,301
Gross Unrealized Losses	'	-2
Fair Value	'	3,119
Other Long-term Investments [Member]	'	'
Available-for-sale – short-term:	'	'
Amortized Cost	'	820
Gross Unrealized Gains	'	2,301
Gross Unrealized Losses	'	-2
Fair Value	'	$3,119

Note_6_Selected_Balance_Sheet_5

Note 6 - Selected Balance Sheet Data (Details) - Amortized Cost and Fair Value of Investments (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Amortized Cost and Fair Value of Investments [Abstract]	'
Due in less than 1 year	$5,885
Due in less than 1 year	5,887
Due within 1-2 years	30,793
Due within 1-2 years	30,837
Due within 2-5 years	14,359
Due within 2-5 years	14,383
Due after 5 years	400
Due after 5 years	400
Total	51,437
Total	$51,507

Note_6_Selected_Balance_Sheet_6

Note 6 - Selected Balance Sheet Data (Details) - Inventories (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Inventories [Abstract]	'	'
Raw materials	$7,468	$4,530
Work in process	15,166	14,144
Finished goods	24,502	18,546
Total	$47,136	$37,220

Note_6_Selected_Balance_Sheet_7

Note 6 - Selected Balance Sheet Data (Details) - Property and Equipment, Net (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]	'	'
Property, plant and equipment, gross	$120,366	$99,122
Accumulated depreciation	-84,434	-70,359
Total	35,932	28,763
Computer Equipment [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Useful life	'3 years	'
Property, plant and equipment, gross	13,790	11,931
Software Development [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Useful life	'5 years	'
Property, plant and equipment, gross	16,085	13,676
Software Development [Member] | Minimum [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Useful life	'3 years	'
Software Development [Member] | Maximum [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Useful life	'5 years	'
Demonstration Equipment [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Useful life	'2 years	'
Property, plant and equipment, gross	25,934	25,422
Development Equipment [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Useful life	'5 years	'
Property, plant and equipment, gross	26,725	21,189
Furniture and Other Equipment [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Useful life	'5 years	'
Property, plant and equipment, gross	18,413	15,062
Leasehold Improvements [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property, plant and equipment, gross	$19,419	$11,842
Leasehold Improvements [Member] | Minimum [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Useful life	'1 year	'
Leasehold Improvements [Member] | Maximum [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Useful life	'40 years	'
Minimum [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Useful life	'3 years	'
Maximum [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Useful life	'5 years	'

Note_6_Selected_Balance_Sheet_8

Note 6 - Selected Balance Sheet Data (Details) - Accrued Expenses (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Accrued Expenses [Abstract]	'	'
Compensation and related expenses	$16,025	$10,007
Vacation	9,310	7,552
Bonuses	6,789	12,211
Commissions	5,179	6,126
Professional fees	2,812	2,245
Other taxes	2,262	3,493
Income taxes	776	3,999
Other	10,595	6,892
Total	$53,748	$52,525

Note_7_Fair_Value_Measurements2

Note 7 - Fair Value Measurements (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Note 7 - Fair Value Measurements (Details) [Line Items]	'	'	'
Available-for-sale Securities	$51,507,000	$129,970,000	'
Available-for-sale Securities, Gross Realized Gain (Loss)	4,469,000	1,300,000	437,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0	0	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net	0	0	'
Auction Rate Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Long-term Investments [Member]	'	'	'
Note 7 - Fair Value Measurements (Details) [Line Items]	'	'	'
Available-for-sale Securities	'	3,100,000	'
Auction Rate Securities [Member] | Fair Value, Inputs, Level 3 [Member]	'	'	'
Note 7 - Fair Value Measurements (Details) [Line Items]	'	'	'
Available-for-sale Securities	4,400,000	'	'
Available-for-sale Securities, Gross Realized Gain (Loss)	2,900,000	'	'
Auction Rate Securities [Member]	'	'	'
Note 7 - Fair Value Measurements (Details) [Line Items]	'	'	'
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	$2,870,000	$32,000	'

Note_7_Fair_Value_Measurements3

Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value [Line Items]	'	'
Investments	$51,507	$129,970
Total financial assets	57,435	130,155
Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Money Market Funds [Member]	'	'
Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value [Line Items]	'	'
Cash equivalents	30	185
Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Commercial Paper [Member]	'	'
Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value [Line Items]	'	'
Cash equivalents	5,898	'
Cash Equivalents [Member] | Money Market Funds [Member]	'	'
Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value [Line Items]	'	'
Cash equivalents	30	185
Cash Equivalents [Member] | Commercial Paper [Member]	'	'
Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value [Line Items]	'	'
Cash equivalents	5,898	'
Fair Value, Inputs, Level 1 [Member]	'	'
Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value [Line Items]	'	'
Total financial assets	30	185
Fair Value, Inputs, Level 2 [Member]	'	'
Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value [Line Items]	'	'
Total financial assets	57,405	126,851
Fair Value, Inputs, Level 3 [Member]	'	'
Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value [Line Items]	'	'
Total financial assets	'	3,119
Short-term Investments [Member] | US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value [Line Items]	'	'
Investments	31,742	77,870
Short-term Investments [Member] | US Government Agencies Debt Securities [Member]	'	'
Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value [Line Items]	'	'
Investments	31,742	77,870
Short-term Investments [Member] | Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]	'	'
Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value [Line Items]	'	'
Investments	19,765	48,981
Short-term Investments [Member] | Corporate Debt Securities [Member]	'	'
Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value [Line Items]	'	'
Investments	19,765	48,981
Short-term Investments [Member]	'	'
Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value [Line Items]	'	'
Investments	'	126,851
Other Long-term Investments [Member] | Auction Rate Securities [Member] | Fair Value, Inputs, Level 3 [Member]	'	'
Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value [Line Items]	'	'
Investments	'	3,119
Other Long-term Investments [Member] | Auction Rate Securities [Member]	'	'
Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value [Line Items]	'	'
Investments	'	3,119
Other Long-term Investments [Member]	'	'
Note 7 - Fair Value Measurements (Details) - Financial Assets Carried at Fair Value [Line Items]	'	'
Investments	'	$3,119

Note_7_Fair_Value_Measurements4

Note 7 - Fair Value Measurements (Details) - Summary of Activity for Auction Rate Securities (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Realized gain recorded in earnings	$0	$0
Auction Rate Securities [Member]	'	'
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'	'
Beginning balance	3,119,000	2,774,000
Unrealized (gain) loss reclassified from/recorded in other comprehensive income	-2,299,000	513,000
Realized gain recorded in earnings	2,870,000	32,000
Sales	-3,690,000	-200,000
Ending balance	'	$3,119,000

Note_8_Goodwill_and_Other_Inta2

Note 8 - Goodwill and Other Intangible Assets (Details) - Activity for Goodwill (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Jun. 01, 2012	Dec. 31, 2013	Dec. 31, 2012	Aug. 24, 2012	Dec. 31, 2013	Dec. 05, 2013
				Anue Systems, Inc [Member]	Anue Systems, Inc [Member]	Anue Systems, Inc [Member]	BreakingPoint Systems, Inc. [Member]	BreakingPoint Systems, Inc. [Member]	BreakingPoint Systems, Inc. [Member]	Net Optics, Inc. [Member]	Net Optics, Inc. [Member]
Goodwill [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Balance at	$371,832,000	$260,457,000	$66,429,000	'	'	$91,008,000	'	'	$102,330,000	'	$112,064,000
Purchase price allocation adjustment	'	'	'	-367,000	'	'	-322,000	'	'	'	'
Goodwill acquired	'	'	'	'	91,376,000	'	'	102,652,000	'	112,064,000	'
Balance at	$371,832,000	$260,457,000	$66,429,000	($367,000)	'	$91,008,000	($322,000)	'	$102,330,000	'	$112,064,000

Note_8_Goodwill_and_Other_Inta3

Note 8 - Goodwill and Other Intangible Assets (Details) - Purchased Intangible Assets (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Other intangible assets:	'	'
Gross	$316,788	$252,383
Accumulated Amortization	-126,839	-95,380
Net	189,949	157,003
Technology [Member]	'	'
Other intangible assets:	'	'
Weighted Average Useful Life	'5 years 6 months	'5 years 146 days
Gross	184,377	141,215
Accumulated Amortization	-81,876	-66,704
Net	102,501	74,511
Customer Relationships [Member]	'	'
Other intangible assets:	'	'
Weighted Average Useful Life	'6 years	'6 years
Gross	71,700	70,376
Accumulated Amortization	-28,911	-18,289
Net	42,789	52,087
Service Agreements [Member]	'	'
Other intangible assets:	'	'
Weighted Average Useful Life	'6 years 73 days	'5 years 255 days
Gross	36,200	22,700
Accumulated Amortization	-9,398	-5,272
Net	26,802	17,428
Noncompete Agreements [Member]	'	'
Other intangible assets:	'	'
Weighted Average Useful Life	'4 years 36 days	'4 years 73 days
Gross	9,000	5,700
Accumulated Amortization	-2,545	-1,520
Net	6,455	4,180
Trademarks [Member]	'	'
Other intangible assets:	'	'
Weighted Average Useful Life	'5 years 36 days	'5 years 109 days
Gross	11,300	8,976
Accumulated Amortization	-3,066	-2,333
Net	8,234	6,643
Other Intangible Assets [Member]	'	'
Other intangible assets:	'	'
Weighted Average Useful Life	'3 years 255 days	'3 years 292 days
Gross	4,211	3,416
Accumulated Amortization	-1,043	-1,262
Net	$3,168	$2,154

Note_8_Goodwill_and_Other_Inta4

Note 8 - Goodwill and Other Intangible Assets (Details) - Estimated Future Amortization Expense of Purchased Intangible Assets (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Estimated Future Amortization Expense of Purchased Intangible Assets [Abstract]	'	'
2014	$46,691	'
2015	41,979	'
2016	38,660	'
2017	31,502	'
2018	20,048	'
Thereafter	11,069	'
Total	$189,949	$157,003

Note_9_Income_Taxes_Details

Note 9 - Income Taxes (Details) (USD $)	3 Months Ended			12 Months Ended
	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Note 9 - Income Taxes (Details) [Line Items]	'	'	'	'	'	'	'
Effective Income Tax Rate Reconciliation, Percent	'	'	'	-9.90%	-134.70%	11.20%	'
Deferred Tax Assets, Gross, Current	'	'	'	$13,700,000	$24,200,000	'	'
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	'	'	'	0	5,600,000	'	'
Deferred Tax Liabilities, Net, Noncurrent	'	'	'	8,100,000	23,900,000	'	'
Valuation Allowance, Deferred Tax Asset, Change in Amount	-12,100,000	-22,700,000	-22,700,000	2,200,000	-34,800,000	800,000	'
Undistributed Earnings of Foreign Subsidiaries	'	'	'	91,800,000	80,400,000	'	'
Unrecognized Tax Benefits	'	'	'	16,766,000	14,454,000	13,232,000	12,303,000
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	'	'	'	8,600,000	'	'	'
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	'	'	'	49,000	63,000	118,000	'
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	'	'	'	172,400	1,500,000	'	'
Domestic Tax Authority [Member]	'	'	'	'	'	'	'
Note 9 - Income Taxes (Details) [Line Items]	'	'	'	'	'	'	'
Tax Credit Carryforward, Amount	'	'	'	17,400,000	'	'	'
Operating Loss Carryforwards	'	'	'	13,600,000	'	'	'
State and Local Jurisdiction [Member]	'	'	'	'	'	'	'
Note 9 - Income Taxes (Details) [Line Items]	'	'	'	'	'	'	'
Tax Credit Carryforward, Amount	'	'	'	17,800,000	'	'	'
Operating Loss Carryforwards	'	'	'	4,900,000	'	'	'
Acquired Corporations [Member]	'	'	'	'	'	'	'
Note 9 - Income Taxes (Details) [Line Items]	'	'	'	'	'	'	'
Operating Loss Carryforwards, Annual Limitation Under Section 382 of Internal Revenue Code	'	'	'	$21,200,000	'	'	'

Note_9_Income_Taxes_Details_Co

Note 9 - Income Taxes (Details) - Components of Income before Income Taxes (USD $)

3 Months Ended

12 Months Ended

In Thousands, unless otherwise specified

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2012

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Components of Income before Income Taxes [Abstract]

'

'

'

'

'

'

'

'

'

'

'

U.S.

'

'

'

'

'

'

'

'

($5,501)

$20,418

$4,179

Foreign

'

'

'

'

'

'

'

'

16,303

-1,051

25,889

Total

($4,842)

[1]

$4,225

$4,387

$7,032

$4,821

$2,669

[2]

$5,265

[3]

$6,612

$10,802

$19,367

$30,068

[1]

During the quarter ended December 31, 2013, we completed the acquisition of Net Optics for approximately $193.8 million.

[2]

During the quarter ended September 30, 2012, we completed the acquisition of BreakingPoint for approximately $163.7 million.

[3]

During the quarter ended June 30, 2012, we completed the acquisition of Anue for approximately $152.4 million

Note_9_Income_Taxes_Details_In

Note 9 - Income Taxes (Details) - Income Tax (Benefit) Expense (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Current:	'	'	'
Federal	$2,920	$9,145	($676)
State	756	2,387	-172
Foreign	1,920	4,735	4,024
Deferred:	'	'	'
Federal	-9,286	-27,910	142
State	-1,342	-10,932	30
Foreign	3,964	-3,518	7
Income tax (benefit) expense	($1,068)	($26,093)	$3,355

Note_9_Income_Taxes_Details_Ef

Note 9 - Income Taxes (Details) - Effective Income Tax Rate Reconciliation (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Effective Income Tax Rate Reconciliation [Abstract]	'	'	'
Federal statutory expense	$3,779	$6,779	$10,526
State taxes, net of federal benefit	-836	-8,828	-58
Research and development credits	-5,128	'	-1,659
Domestic production deduction	-499	-826	'
Stock-based compensation	1,750	1,738	1,082
Foreign rate differential	-2,935	-4,386	-5,029
Acquisition related costs	'	991	113
Deemed Dividend	817	'	'
Inter-company royalty	3,932	'	'
Valuation allowance	1,111	-22,578	-749
Release of uncertain tax positions	-2,106	'	'
Other	-953	1,017	-871
Income tax (benefit) expense	($1,068)	($26,093)	$3,355
Net effective income tax rate	-9.90%	-134.70%	11.20%

Note_9_Income_Taxes_Details_De

Note 9 - Income Taxes (Details) - Deferred Tax Assets and Liabilities (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Deferred tax assets:	'	'
Allowance for doubtful accounts	$6	$326
Research and development credit carryforward	18,375	14,241
Foreign tax credit carryforward	455	1,418
Deferred revenue	2,942	2,879
Stock-based compensation	9,698	7,350
Inventory adjustments	6,238	5,139
Net operating loss carryforward	5,585	10,543
Unrealized loss on investments	'	3,631
Realized loss on investments	3,211	'
Accrued liabilities and other	4,782	4,472
Depreciation & amortization	'	3,468
	51,292	53,467
Valuation allowance	-4,144	-1,977
	47,148	51,490
Deferred tax liabilities:	'	'
Depreciation and amortization	-27,351	-45,635
Intercompany royalty	-14,259	'
Net deferred tax assets	$5,538	$5,855

Note_9_Income_Taxes_Details_Re

Note 9 - Income Taxes (Details) - Reconciliation of the Beginning and Ending Amounts of Gross Unrecognized Tax Benefits (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Reconciliation of the Beginning and Ending Amounts of Gross Unrecognized Tax Benefits [Abstract]	'	'	'
Unrecognized Tax Benefits - Beginning balance	$14,454	$13,232	$12,303
Acquired unrecognized tax benefits	'	300	'
Gross increases – Tax positions taken in prior period	1,364	'	'
Gross decreases – Tax positions taken in prior period	-264	'	-140
Gross increases – Tax positions taken in current period	2,757	1,834	2,256
Lapse of statute of limitations	-1,545	-912	-1,187
Unrecognized Tax Benefits – ending balance	$16,766	$14,454	$13,232

Note_10_Commitments_and_Contin2

Note 10 - Commitments and Contingencies (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Note 10 - Commitments and Contingencies (Details) [Line Items]	'	'	'
Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals	$0.80	'	'
Operating Leases, Rent Expense, Net	$9.90	$8.90	$7.70

Note_10_Commitments_and_Contin3

Note 10 - Commitments and Contingencies (Details) - Future Minimum Lease Commitments (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Future Minimum Lease Commitments [Abstract]	'
	$11,261	[1]
	10,499	[1]
	7,955	[1]
	5,557	[1]
	4,790	[1]
	14,891	[1]
	$54,953	[1]
[1]	Minimum payments have not been reduced by minimum sublease rentals of $0.8 million due in the future under non-cancelable subleases.

Note_11_Shareholders_Equity_De

Note 11 - Shareholders' Equity (Details) (USD $)

12 Months Ended

12 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

3 Months Ended

12 Months Ended

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 1997

Dec. 31, 2008

Dec. 31, 1997

Dec. 31, 2008

Jun. 30, 2013

Jun. 30, 2013

Dec. 31, 2013

Jun. 30, 2013

Jun. 30, 2013

Dec. 31, 1997

Dec. 31, 1997

Dec. 31, 1997

Dec. 31, 1997

Dec. 31, 2013

Jun. 30, 2013

Jun. 30, 2013

Dec. 31, 2013

Dec. 31, 2008

Sep. 30, 2000

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Jun. 30, 2013

Apr. 30, 2013

Nov. 30, 2012

Jun. 30, 2010

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2010

ISOs Granted to Employee With More Than 10% Voting Common Stock [Member]

ISOs Granted to Employee With More Than 10% Voting Common Stock [Member]

Employee Stock Option [Member]

Employee Stock Option [Member]

Options and Share Appreciation Rigjhts [Member]

Restricted Stock Units (RSUs) [Member]

Restricted Stock Units (RSUs) [Member]

Forfeiture of Equity Awards [Member]

Regrant of Equity Awards [Member]

Termination for Cause [Member]

Termination Other Than for Cause or As a Result of Death or Disability [Member]

Termination As a Result of Disability or Death [Member]

The 1997 Plan [Member]

The 1997 Plan [Member]

The 2008 Plan [Member]

The 2008 Plan [Member]

The 2008 Plan [Member]

The 2008 Plan [Member]

The 2000 Plan [Member]

The 2000 Plan [Member]

The 2000 Plan [Member]

The 2000 Plan [Member]

The 2010 Purchase Plan [Member]

The 2010 Purchase Plan [Member]

The 2010 Purchase Plan [Member]

The 2010 Purchase Plan [Member]

The 2010 Purchase Plan [Member]

The 2010 Purchase Plan [Member]

The 2010 Purchase Plan [Member]

The 2010 Purchase Plan [Member]

The 1997 Plan [Member]

The 2008 Plan [Member]

The 1997 Plan [Member]

The 2008 Plan [Member]

The 2008 Plan [Member]

The 2008 Plan [Member]

Operating Expense [Member]

Operating Expense [Member]

The 1997 Plan [Member]

The 1997 Plan [Member]

The 1997 Plan [Member]

Non-Employee Director [Member]

Note 11 - Shareholders' Equity (Details) [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Award Expiration Period

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'10 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Minimum Option Grant Price as Percentage of Fair Market Value of Common Stock

'

'

'

110.00%

110.00%

'

'

'

'

'

'

'

'

'

'

100.00%

'

'

'

'

100.00%

'

'

'

'

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period

'

'

'

'

'

'4 years

'4 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Exercise Period of Vested Options Following Employment Termination

'

'

'

'

'

'

'

'

'

'

'

'

'30 days

'90 days

'180 days

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number

4,998,000

6,333,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

150,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Increase in Number of Shares of Common Stock Available for Future Grants

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

9,800,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

29,000,000

'

'

4,500,000

'

'

'

'

'

'

3,800,000

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

13,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Calendar Year Grant Limit

'

'

'

'

'

'

'

1,000,000

1,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Individual Award Limit (in Dollars)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$500,000

$2,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Quantifying Misstatement in Current Year Financial Statements, Amount (in Dollars)

'

'

'

'

'

'

'

'

'

'

-4,000,000

3,700,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share)

$6.92

$5.89

$6.40

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value (in Dollars)

12,500,000

14,600,000

11,300,000

'

'

'

'

'

'

3,600,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition

'1 year 120 days

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value (in Dollars per share)

'

'

'

'

'

'

'

'

'

$7,800,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms

'

'

'

'

'

'

'

'

'

'1 year 160 days

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

15.00%

'

'

'

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Amount (in Dollars)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

21,250

'

'

'

'

'

'

'

'

'

'

'

Percentage of Purchase Price Per Share

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

85.00%

'

'

'

'

'

'

'

'

'

'

'

Length of Offering Period

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'24 months

'

'

'

'

'

'

'

'

'

'

'24 months

Length of Purchase Intervals

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'6 months

'

'

'

'

Stock Issued During Period, Shares, Employee Stock Purchase Plans

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

0

105,000

375,000

'

'

'

'

918,000

562,000

156,000

'

Automatic Annual Increase in Number of Shares Reserved for Issuance

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

500,000

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Term of Award Plan

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'10 years

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2,000,000

500,000

500,000

'

'

'

'

'

Shares Added to Initial Share Reserve Pursuant to the Automatic Annual Increase Provisions

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2,164,000

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term

'3 years 219 days

'4 years 36 days

'3 years 109 days

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'1 year 3 months

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate

0.60%

0.60%

1.30%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

0.90%

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate

0.00%

0.00%

0.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

0.00%

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate

48.90%

51.80%

50.50%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

48.40%

'

'

'

Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized (in Dollars)

26,300,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax (in Dollars)

4,400,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax (in Dollars)

1,700,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax (in Dollars)

'

1,100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax (in Dollars)

'

$447,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Note_11_Shareholders_Equity_De1

Note 11 - Shareholders' Equity (Details) - Stock Option Activity (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Stock Option Activity [Abstract]	'	'
Number of options	4,998	6,333
Weighted average exercise price per share	$13.49	$12.37
Weighted average remaining contractual life	'4 years 135 days	'5 years 14 days
Aggregate intrinsic value	$8,932	$30,281
Vested and expected to vest as of December 31, 2013	4,797	'
Vested and expected to vest as of December 31, 2013	$13.40	'
Vested and expected to vest as of December 31, 2013	'4 years 98 days	'
Vested and expected to vest as of December 31, 2013	8,884	'
Exercisable as of December 31, 2013	2,886	'
Exercisable as of December 31, 2013	$11.98	'
Exercisable as of December 31, 2013	'3 years 131 days	'
Exercisable as of December 31, 2013	$8,101	'
Granted	1,161	'
Granted	$16.31	'
Exercised	-1,117	'
Exercised	$8.49	'
Forfeited/canceled	-1,379	'
Forfeited/canceled	$14.76	'

Note_11_Shareholders_Equity_De2

Note 11 - Shareholders' Equity (Details) - RSU Activity (Restricted Stock Units (RSUs) [Member], USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Restricted Stock Units (RSUs) [Member]	'	'
Note 11 - Shareholders' Equity (Details) - RSU Activity [Line Items]	'	'
Number of Awards	1,750	1,692
Weighted Average Grant Date Fair Value Per Share	$15.43	$12.69
Awarded	1,039	'
Awarded	$17.06	'
Vested	-687	'
Vested	$11.33	'
Forfeited/canceled	-294	'
Forfeited/canceled	$14.97	'

Note_11_Shareholders_Equity_De3

Note 11 - Shareholders' Equity (Details) - Black-Scholes Option-Pricing Model Assumptions	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Black-Scholes Option-Pricing Model Assumptions [Abstract]	'	'	'
Expected lives (in years)	'3 years 219 days	'4 years 36 days	'3 years 109 days
Risk-free interest rates	0.60%	0.60%	1.30%
Dividend yield	0.00%	0.00%	0.00%
Expected volatility	48.90%	51.80%	50.50%

Note_11_Shareholders_Equity_De4

Note 11 - Shareholders' Equity (Details) - Components of Accumulated Other Comprehensive Income, Net of Income Taxes (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Components of Accumulated Other Comprehensive Income, Net of Income Taxes [Abstract]	'		'		'
Gains and Losses on Available-for-Sale Securities	$42	[1]	$2,070	[1]	'
Foreign Currency Items	-419	[1]	219	[1]	'
Total	-377		2,289		'
Other comprehensive income before reclassifications	702	[1]	'		'
Other comprehensive income before reclassifications	-638	[1]	'		'
Other comprehensive income before reclassifications	64		'		'
Amounts reclassified from accumulated other comprehensive income (b)	-2,730	[1],[2]	'		'
Amounts reclassified from accumulated other comprehensive income (b)	'	[1],[2]	'		'
Amounts reclassified from accumulated other comprehensive income (b)	-2,730	[2]	'		'
Net current-period other comprehensive income	-2,028	[1]	'		'
Net current-period other comprehensive income	-638	[1]	-527		232
Net current-period other comprehensive income	($2,666)		'		'
[1]	All amounts are net-of-tax. Amounts in parentheses indicate reductions.
[2]	Amount represents gain on the sale of securities and is included as a component of Interest income and other, net in the consolidated statements of operations.

Note_12_Retirement_Plan_Detail

Note 12 - Retirement Plan (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Compensation and Retirement Disclosure [Abstract]	'	'	'
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	50.00%	'	'
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount	$2,500	'	'
Defined Contribution Plan, Employer Discretionary Contribution Amount	$1,500,000	$870,000	$845,000

Note_13_Earnings_Per_Share_Det

Note 13 - Earnings Per Share (Details)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Convertible Debt Securities [Member]	'	'	'
Note 13 - Earnings Per Share (Details) [Line Items]	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	10.3	'	10.3
Stock Options and Other Share-based Awards [Member]	'	'	'
Note 13 - Earnings Per Share (Details) [Line Items]	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	2.2	2.3	1.1

Note_13_Earnings_Per_Share_Det1

Note 13 - Earnings Per Share (Details) - Computation of Basic and Diluted Earnings Per Share (USD $)

3 Months Ended

12 Months Ended

In Thousands, except Per Share data, unless otherwise specified

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2012

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Numerator for basic earnings per share:

'

'

'

'

'

'

'

'

'

'

'

Net income (in Dollars)

($3,069)

[1],[2]

$4,102

[1]

$3,017

[1]

$7,820

[1]

$3,653

[1]

$10,944

[1],[3]

$25,696

[1],[4]

$5,167

[1]

$11,870

$45,460

$26,713

Weighted average common shares outstanding

'

'

'

'

'

'

'

'

75,757

72,183

69,231

Basic earnings per share (in Dollars per share)

($0.04)

[2]

$0.05

$0.04

$0.10

$0.05

$0.15

[3]

$0.36

[4]

$0.07

$0.16

$0.63

$0.39

Numerator for diluted earnings per share:

'

'

'

'

'

'

'

'

'

'

'

Net income (in Dollars)

-3,069

[1],[2]

4,102

[1]

3,017

[1]

7,820

[1]

3,653

[1]

10,944

[1],[3]

25,696

[1],[4]

5,167

[1]

11,870

45,460

26,713

Interest expense on convertible senior notes, net of tax (in Dollars)

'

'

'

'

'

'

'

'

'

4,399

'

Net income used for diluted earnings per share (in Dollars)

'

'

'

'

'

'

'

'

$11,870

$49,859

$26,713

Stock options and other share-based awards

'

'

'

'

'

'

'

'

1,756

2,031

2,433

Convertible senior notes

'

'

'

'

'

'

'

'

'

10,291

'

Dilutive potential common shares

'

'

'

'

'

'

'

'

77,513

84,505

71,664

Diluted earnings per share (in Dollars per share)

($0.04)

[2]

$0.05

$0.04

$0.10

$0.05

$0.14

[3]

$0.32

[4]

$0.07

$0.15

$0.59

$0.37

[1]

For the quarters ended September 30, 2012 and June 30, 2012, we recorded partial release of our valuation allowance of $12.1 million and $22.7 million in the third and second quarters of 2012, respectively.

[2]

During the quarter ended December 31, 2013, we completed the acquisition of Net Optics for approximately $193.8 million.

[3]

During the quarter ended September 30, 2012, we completed the acquisition of BreakingPoint for approximately $163.7 million.

[4]

During the quarter ended June 30, 2012, we completed the acquisition of Anue for approximately $152.4 million

Note_14_Quarterly_Financial_Su2

Note 14 - Quarterly Financial Summary (Unaudited) (Details) (USD $)

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2012

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2013

Sep. 30, 2012

Dec. 31, 2013

Jun. 30, 2012

Dec. 31, 2013

Cost of Revenues [Member]

Cost of Revenues [Member]

Cost of Revenues [Member]

Cost of Revenues [Member]

Cost of Revenues [Member]

Cost of Revenues [Member]

Cost of Revenues [Member]

Cost of Revenues [Member]

Net Optics, Inc. [Member]

BreakingPoint Systems, Inc. [Member]

BreakingPoint Systems, Inc. [Member]

Anue Systems, Inc [Member]

Anue Systems, Inc [Member]

Note 14 - Quarterly Financial Summary (Unaudited) (Details) [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Amortization of Intangible Assets

'

'

'

$40,805,000

$30,018,000

$15,980,000

$6,700,000

$6,400,000

$6,400,000

$6,500,000

$7,000,000

$7,000,000

$3,600,000

$2,700,000

'

'

'

'

'

Valuation Allowance, Deferred Tax Asset, Change in Amount

-12,100,000

-22,700,000

-22,700,000

2,200,000

-34,800,000

800,000

'

'

'

'

'

'

'

'

'

'

-264,000

'

-22,000

Payments to Acquire Businesses, Gross

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$193,800,000

$163,700,000

$2,400,000

$152,400,000

'

Note_14_Quarterly_Financial_Su3

Note 14 - Quarterly Financial Summary (Unaudited) (Details) - Quarterly Financial Summary (Unaudited) (USD $)	3 Months Ended																12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2012		Sep. 30, 2012		Jun. 30, 2012		Mar. 31, 2012		Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Quarterly Financial Summary (Unaudited) [Abstract]	'		'		'		'		'		'		'		'		'	'	'
Total revenues	$120,629	[1]	$113,164		$112,004		$121,459		$125,469		$110,605	[2]	$90,702	[3]	$86,658		$467,256	$413,434	$311,370
Total cost of revenues (1)	36,300	[1],[4]	30,997	[4]	30,829	[4]	30,926	[4]	32,064	[4]	30,241	[2],[4]	20,585	[3],[4]	19,593	[4]	'	'	'
Gross profit	84,329	[1]	82,167		81,175		90,533		93,405		80,364	[2]	70,117	[3]	67,065		'	'	'
(Loss) income before income taxes	-4,842	[1]	4,225		4,387		7,032		4,821		2,669	[2]	5,265	[3]	6,612		10,802	19,367	30,068
Net (loss) income (2)	($3,069)	[1],[5]	$4,102	[5]	$3,017	[5]	$7,820	[5]	$3,653	[5]	$10,944	[2],[5]	$25,696	[3],[5]	$5,167	[5]	$11,870	$45,460	$26,713
Basic (in Dollars per share)	($0.04)	[1]	$0.05		$0.04		$0.10		$0.05		$0.15	[2]	$0.36	[3]	$0.07		$0.16	$0.63	$0.39
Diluted (in Dollars per share)	($0.04)	[1]	$0.05		$0.04		$0.10		$0.05		$0.14	[2]	$0.32	[3]	$0.07		$0.15	$0.59	$0.37
[1]	During the quarter ended December 31, 2013, we completed the acquisition of Net Optics for approximately $193.8 million.
[2]	During the quarter ended September 30, 2012, we completed the acquisition of BreakingPoint for approximately $163.7 million.
[3]	During the quarter ended June 30, 2012, we completed the acquisition of Anue for approximately $152.4 million
[4]	For the quarters ended December 31, 2013, September 30, 2013, June 30, 2013, March 31, 2013, December 31, 2012, September 30, 2012, June 30, 2012, and March 31, 2012, total cost of revenues include charges related to amortization of intangible assets of $6.7 million, $6.4 million, $6.4 million, $6.5 million, $7.0 million, $7.0 million, $3.6 million, and $2.7 million, respectively.
[5]	For the quarters ended September 30, 2012 and June 30, 2012, we recorded partial release of our valuation allowance of $12.1 million and $22.7 million in the third and second quarters of 2012, respectively.