Applied Micro Circuits (AMCC) 10-Q 30 Jan 15 2015 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Dec. 31, 2014	Jan. 27, 2015
Document and Entity Information [Abstract]
Entity Registrant Name	APPLIED MICRO CIRCUITS CORP
Entity Central Index Key	711065
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Dec-14
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	-28
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		79,140,131

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$50,080	$71,539
Short-term investments-available-for-sale	32,943	35,044
Accounts receivable, net	19,247	25,178
Inventories	24,222	18,946
Other current assets	15,203	16,799
Total current assets	141,695	167,506
Property and equipment, net	20,946	20,746
Goodwill	11,425	11,425
Purchased intangibles, net	0	105
Other assets	3,976	7,754
Total assets	178,042	207,536
Current liabilities:
Accounts payable	22,155	26,194
Accrued payroll and related expenses	5,344	5,532
Veloce accrued liability	8,323	11,985
Other accrued liabilities	8,659	10,877
Deferred revenue	380	567
Total current liabilities	44,861	55,155
Non-current liabilities	4,134	3,145
Commitments and contingencies (Note 7)
Stockholders’ equity:
Preferred stock, $0.01 par value: Authorized shares - 2,000, none issued and outstanding	0	0
Common stock, $0.01 par value: Authorized shares - 375,000 at December 31, 2014 and March 31, 2014; Issued and outstanding shares - 79,136 at December 31, 2014 and 77,677 at March 31, 2014	791	777
Additional paid-in capital	6,022,231	6,005,365
Accumulated other comprehensive loss	-6,299	-6,143
Accumulated deficit	-5,887,676	-5,850,763
Total stockholders’ equity	129,047	149,236
Total liabilities and stockholders’ equity	$178,042	$207,536

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Mar. 31, 2014
Statement of Financial Position [Abstract]
Preferred stock, par value (in Dollars per share)	$0.01	$0.01
Preferred stock, shares authorized (shares)	2,000,000	2,000,000
Preferred stock, shares issued (shares)	0	0
Preferred stock, shares outstanding (shares)	0	0
Common stock, par value (in Dollars per share)	$0.01	$0.01
Common stock, shares authorized (shares)	375,000,000	375,000,000
Common stock, shares issued (shares)	79,136,000	77,677,000
Common stock, shares outstanding (shares)	79,136,000	77,677,000

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Operations (Unaudited) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Net revenues	$36,747	$54,844	$127,964	$164,379
Cost of revenues	14,842	21,644	52,815	65,383
Gross profit	21,905	33,200	75,149	98,996
Operating expenses:
Research and development	24,721	29,870	82,636	120,926
Selling, general and administrative	8,707	10,930	25,684	29,602
Gain on sale of TPack	0	0	0	-19,699
Amortization of purchased intangible assets	0	62	105	254
Restructuring	221	38	1,322	1,130
Total operating expenses	33,649	40,900	109,747	132,213
Operating loss	-11,744	-7,700	-34,598	-33,217
Interest income, net	485	525	1,214	4,679
Other (expense) income, net	-10	92	-2,536	309
Loss before income taxes	-11,269	-7,083	-35,920	-28,229
Income tax expense	862	201	993	581
Net loss	($12,131)	($7,284)	($36,913)	($28,810)
Basic and diluted net loss per share (in Dollars per share)	($0.15)	($0.10)	($0.47)	($0.40)
Shares used in calculating basic and diluted net loss per share (in Shares)	78,920	73,989	78,442	71,986

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Comprehensive Loss (unaudited) (USD $)	3 Months Ended				9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2014		Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net loss	($12,131)		($7,284)		($36,913)		($28,810)
Other comprehensive loss, net of tax:
Unrealized (loss) gain on investments	-78	[1]	-179	[1]	218	[1]	-5,404	[1]
Loss on foreign currency translation	-159		-37		-374		-377
Other comprehensive loss, net of tax	-237		-216		-156		-5,781
Total comprehensive loss	-12,368		-7,500		-37,069		-34,591
Reclassification adjustment from AOCI to earnings, short term investments	($123)		($6)		($123)		($3,290)
[1]	The amounts reclassified from accumulated other comprehensive loss and recorded in interest income, net in the Condensed Consolidated Statement of Operations relating to short-term investments were $0.1 million for the three and nine months ended December 31, 2014 and zero and $3.3 million for the three and nine months ended December 31, 2013, respectively. Refer to Note 2, Certain Financial Statement Information, to the Condensed Consolidated Financial Statements for additional details.

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Adjustments to reconcile net loss to net cash used for operating activities:
Net loss	($36,913)	($28,810)
Depreciation	6,624	7,728
Amortization of purchased intangible assets	105	420
Stock-based compensation expense	14,303	13,430
Veloce acquisition consideration	7,140	42,684
Gain on sale of TPack	0	-19,699
Loss on disposals of property and equipment	22	27
Impairment of a strategic investment	2,500	0
Non-cash restructuring charges	14	298
Tax effect on other comprehensive loss	-34	0
Changes in operating assets and liabilities:
Accounts receivable, net	5,931	-4,459
Inventories	-5,271	2,415
Assets held for sale	0	-14,260
Other assets	484	-16,475
Accounts payable	-3,629	-4,423
Accrued payroll and other accrued liabilities	-927	610
Veloce accrued liability	-8,981	-45,432
Deferred revenue	-188	-449
Net cash used for operating activities	-19,788	-33,445
Investing activities:
Proceeds from sales and maturities of short-term investments	5,075	26,594
Purchases of short-term investments	-2,722	-16,241
Proceeds from sale of property and equipment	1	20
Purchase of property and equipment	-7,571	-5,616
Proceeds from sale of strategic equity investment	0	1,286
Proceeds from sale of TPack, net	-3,353	-29,498
Net cash (used for) provided by investing activities	-1,864	35,541
Financing activities:
Proceeds from issuance of common stock	1,890	8,582
Funding of restricted stock units withheld for taxes	-1,609	-5,518
Other	-88	-595
Net cash provided by financing activities	193	2,469
Net (decrease) increase in cash and cash equivalents	-21,459	4,565
Cash and cash equivalents at beginning of year	71,539	19,065
Cash and cash equivalents at end of period	50,080	23,630
Supplementary cash flow disclosures:
Cash paid for income taxes	643	609
Common stock issued for Veloce merger consideration	$872	$29,209

Summary_of_Significant_Account

Summary of Significant Accounting Policies	9 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
	Basis of Presentation
	The Condensed Consolidated Financial Statements include all the accounts of Applied Micro Circuits Corporation (the "Company") and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.
	In management’s opinion, the unaudited Condensed Consolidated Financial Statements reflect all adjustments (consisting only of normal recurring adjustments) necessary to fairly present the Company's financial position, results of operations and cash flows. Interim period operating results do not necessarily indicate the results that may be expected for any other interim period or for the full fiscal year. The Condensed Consolidated Balance Sheet as of March 31, 2014 has been derived from the audited Consolidated Financial Statements as of that date but does not include all disclosures required by U.S. generally accepted accounting principles, or GAAP. These financial statements and accompanying notes should be read in conjunction with the Consolidated Financial Statements and notes thereto in the Company's Annual Report on Form 10-K for the fiscal year ended March 31, 2014.
	Use of Estimates
	The preparation of financial statements in accordance with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of net revenue and expenses in the reporting period. The Company regularly evaluates estimates and assumptions related to its:
	•	capitalized mask sets including their useful lives, which affect cost of goods sold and property and equipment or Research and Development ("R&D") expenses, if not capitalized;
	•	inventory valuation, warranty liabilities and revenue reserves, which affect cost of sales, gross margin, and revenues;
	•	allowance for doubtful accounts, which affects operating expenses;
	•	unrealized losses or other-than-temporary impairments of short-term investments available for sale, which affect interest income (expense), net;
	•	valuation of other long-lived assets and goodwill, which affects depreciation and impairment of long-lived assets, impairment of goodwill and apportionment of goodwill related to divestitures;
	•	valuation of cost method investments, which affects impairment of strategic investments;
	•	potential costs of litigation, which affect operating expenses;
	•	valuation of deferred income taxes, which affects income tax expense (benefit); and
	•	stock-based compensation, which affects gross margin and operating expenses.
	The Company bases its estimates and assumptions on historical experience and on various other factors that it believes to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. The actual results experienced by the Company may differ materially and adversely from management’s estimates. To the extent there are material differences between the estimates and actual results, future results of operations will be affected.
	New Accounting Pronouncements
	In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standard Update ("ASU") No. 2014-09, "Revenue from Contracts with Customers", which will supersede most of the existing revenue recognition guidance under U.S. GAAP. This ASU requires an entity to recognize revenue when it transfers 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. This pronouncement is effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early adoption is not permitted. The ASU allows for either full retrospective or modified retrospective adoption. The Company is currently evaluating the potential effect of this ASU on its financial statements and related disclosures.

Certain_Financial_Statement_In

Certain Financial Statement Information	9 Months Ended
	Dec. 31, 2014
Certain Financial Statement Information [Abstract]
CERTAIN FINANCIAL STATEMENT INFORMATION	CERTAIN FINANCIAL STATEMENT INFORMATION
	Accounts receivable, net:
			December 31,				March 31,
			2014				2014
			(In thousands)
	Accounts receivable		$	19,612			$	25,629
	Less: allowance for bad debts		(365		)		(451		)
			$	19,247			$	25,178
	Inventories:
			December 31,				March 31,
			2014				2014
			(In thousands)
	Finished goods		$	16,618			$	9,375
	Work in process		6,494				6,510
	Raw materials		1,110				3,061
			$	24,222			$	18,946
	Other current assets:
			December 31,				March 31,
			2014				2014
			(In thousands)
	Prepaid expenses		$	12,843			$	10,978
	Executive deferred compensation assets		1,108				1,035
	Proceeds receivable from sale of strategic investment		—				3,353
	Other		1,252				1,433
			$	15,203			$	16,799
	Property and equipment:
			Useful		December 31,				March 31,
			Life		2014				2014
			(In years)		(In thousands)
	Machinery and equipment*		5-Mar		$	39,520			$	44,503
	Leasehold improvements		5-Jan		10,473				11,574
	Computers, office furniture and equipment*		5-Mar		44,581				43,365
					94,574				99,442
	Less: accumulated depreciation and amortization*				(73,628		)		(78,696		)
					$	20,946			$	20,746
	*During the three months ended December 31, 2014, the Company wrote off fully depreciated assets with an acquired cost of $11.8 million.
	Goodwill and purchased intangibles:
	Goodwill is as follows:
		December 31,				March 31,
		2014				2014
		(In thousands)
	Goodwill	$	11,425			$	11,425
	Purchase-related intangibles are as follows:
			31-Dec-14														31-Mar-14
			Gross				Accumulated				Net				Weighted		Gross				Accumulated				Net				Weighted
							Amortization								average						Amortization								average
							and Impairments								remaining						and Impairments								remaining
															useful life														useful life
			(In thousands)												(In years)		(In thousands)												(In years)
	Developed technology/in-process research and development		$	425,000			$	(425,000	)		$	—			0		$	425,000			$	(425,000	)		$	—			0
	Customer relationships		6,330				(6,330		)		—				0		6,330				(6,225		)		105				0.4
	Patents/core technology rights/trade name		62,306				(62,306		)		—				0		62,306				(62,306		)		—				0
			$	493,636			$	(493,636	)		$	—					$	493,636			$	(493,531	)		$	105
	Other assets:
			December 31,				March 31,
			2014				2014
			(In thousands)
	Non-current portion of prepaid expenses		$	2,957			$	4,235
	Strategic investments*		500				3,000
	Other		519				519
			$	3,976			$	7,754
	*Strategic investments
	The Company has entered into certain equity investments in privately held businesses to achieve certain strategic business objectives. The Company’s investments in equity securities of privately held businesses are accounted for under the cost method. Under the cost method, strategic investments in which the Company holds less than a 20% voting interest and in which the Company does not have the ability to exercise significant influence are carried at cost reduced by other-than-temporary impairments, as appropriate. The Company periodically reviews these investments for other-than-temporary declines in fair value based on the specific identification method and writes down investments when an other-than-temporary decline has occurred. During the three months ended December 31, 2014 and during the three and nine months ended December 31, 2013, the Company did not record any other-than-temporary impairment charges with respect to its strategic investments. During the nine months ended December 31, 2014, the Company recorded an other-than-temporary impairment charge with respect to one of its strategic investments in the amount of $2.5 million.
	Other accrued liabilities:
		December 31,				March 31,
		2014				2014
		(In thousands)
Employee related liabilities		$	1,622			$	1,733
Executive deferred compensation		1,385				1,314
Income taxes		1,870				962
Professional fees		755				1,259
Other		3,027				5,609
		$	8,659			$	10,877
Short-term investments:
The following is a summary of cash, cash equivalents and available-for-sale investments by type of instrument (in thousands):
		31-Dec-14																31-Mar-14
		Amortized				Gross Unrealized								Estimated				Amortized				Gross Unrealized							Estimated
		Cost				Gains				Losses				Fair Value				Cost				Gains				Losses			Fair Value
Cash		$	40,828			$	—			$	—			$	40,828			$	65,867			$	—			$	—		$	65,867
Cash equivalents		9,252				—				—				9,252				5,672				—				—			5,672
U.S. Treasury securities and agency bonds		1,475				—				—				1,475				2,838				—				—			2,838
Corporate bonds		10,911				14				(9		)		10,916				10,599				30				(2		)	10,627
Mortgage-backed and asset-backed securities*		1,614				291				(2		)		1,903				1,793				297				(16		)	2,074
Closed-end bond funds		13,249				2,248				(206		)		15,291				14,373				2,392				(402		)	16,363
Preferred stock		2,406				952				—				3,358				2,406				736				—			3,142
		$	79,735			$	3,505			$	(217	)		$	83,023			$	103,548			$	3,455			$	(420	)	$	106,583
Reported as:
Cash and cash equivalents														$	50,080														$	71,539
Short-term investments available-for-sale														32,943															35,044
														$	83,023														$	106,583
* At December 31, 2014 and March 31, 2014, approximately $1.0 million and $1.1 million of the estimated fair value presented were mortgage-backed securities, respectively.
The established guidelines for measuring fair value and expanded disclosures regarding fair value measurements are defined as a three-level valuation hierarchy for disclosure of fair value measurements as follows:
Level 1 — Inputs are unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date.
Level 2 — Inputs (other than quoted market prices included in Level 1) are either directly or indirectly observable for the asset or liability through correlation with market data at the measurement date and for the duration of the instrument’s anticipated life.
Level 3 — Inputs reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. Consideration is given to the risk inherent in the valuation technique and the risk inherent in the inputs to the model. Valuation of instruments includes unobservable inputs to the valuation methodology that are significant to the measurement of the fair value of assets or liabilities.
The following is a summary of cash, cash equivalents and available-for-sale investments by type of instrument measured at fair value on a recurring basis (in thousands):
		31-Dec-14																31-Mar-14
		Level 1				Level 2				Level 3				Total				Level 1				Level 2				Level 3			Total
Cash		$	40,828			$	—			$	—			$	40,828			$	65,867			$	—			$	—		$	65,867
Cash equivalents		9,252				—				—				9,252				5,672				—				—			5,672
U.S. Treasury securities and agency bonds		1,475				—				—				1,475				2,838				—				—			2,838
Corporate bonds		—				10,916				—				10,916				—				10,627				—			10,627
Mortgage-backed and asset-backed securities		—				1,903				—				1,903				—				2,074				—			2,074
Closed-end bond funds		15,291				—				—				15,291				16,363				—				—			16,363
Preferred stock		—				3,358				—				3,358				—				3,142				—			3,142
		$	66,846			$	16,177			$	—			$	83,023			$	90,740			$	15,843			$	—		$	106,583
There were no significant transfers in and out of Level 1 and Level 2 fair value measurement categories during the three and nine months ended December 31, 2014 and 2013.
The following is a summary of the cost and estimated fair values of available-for-sale securities with stated maturities, which include U.S. Treasury securities and agency bonds, corporate bonds and mortgage-backed and asset-backed securities, by contractual maturity (in thousands):
		31-Dec-14
		Cost				Estimated Fair Value
Less than 1 year		$	5,745			$	5,837
Mature in 1 – 2 years		7,147				7,170
Mature in 3 – 5 years		291				305
Mature after 5 years		817				982
		$	14,000			$	14,294
The following is a summary of gross unrealized losses (in thousands):
		Less Than 12 Months of								12 Months or More of								Total
		Unrealized Losses								Unrealized Losses
As of December 31, 2014		Estimated				Gross				Estimated				Gross				Estimated				Gross
		Fair				Unrealized				Fair				Unrealized				Fair				Unrealized
		Value				Losses				Value				Losses				Value				Losses
Corporate bonds		$	3,750			$	(9	)		$	—			$	—			$	3,750			$	(9	)
Mortgage-backed and asset-backed securities		275				(2		)		121								396				(2		)
Closed-end bond funds		61				(2		)		4,255				(204		)		4,316				(206		)
		$	4,086			$	(13	)		$	4,376			$	(204	)		$	8,462			$	(217	)
		Less Than 12 Months of								12 Months or More of								Total
		Unrealized Losses								Unrealized Losses
As of March 31, 2014		Estimated				Gross				Estimated				Gross				Estimated				Gross
		Fair				Unrealized				Fair				Unrealized				Fair				Unrealized
		Value				Losses				Value				Losses				Value				Losses
Corporate bonds		$	992			$	(2	)		$	—			$	—			$	992			$	(2	)
Mortgage-backed and asset-backed securities		431				(16		)		—				—				431				(16		)
Closed-end bond funds		4,819				(333		)		405				(69		)		5,224				(402		)
		$	6,242			$	(351	)		$	405			$	(69	)		$	6,647			$	(420	)
Other-Than-Temporary Impairment
Based on an evaluation of securities that have been in a loss position, the Company did not recognize any other-than-temporary impairment charges for the three and nine months ended December 31, 2014 and 2013. The Company considered various factors which included a credit and liquidity assessment of the underlying securities and the Company’s intent and ability to hold the underlying securities until the estimated date of recovery of its amortized cost. As of December 31, 2014 and March 31, 2014, the Company also had $3.5 million in gross unrealized gains. The basis for computing realized gains or losses is by specific identification.
Warranty reserves:
The Company's products typically carry a one-year warranty. The Company establishes reserves for estimated product warranty costs at the time revenue is recognized. Although the Company engages in extensive product quality programs and processes, its warranty obligation is affected by product failure rates, use of materials, and service delivery costs incurred in correcting any product failure. Should actual product failure rates, use of materials or service delivery costs differ from the Company’s estimates, additional warranty reserves could be required, which could reduce its gross margin.
The following table summarizes warranty reserve activity (in thousands):
	Three Months Ended								Nine Months Ended
	December 31,								December 31,
	2014				2013				2014				2013
Beginning balance	$	175			$	187			$	199			$	220
Additions during the period	41				54				40				28
Settlements and expirations	(75		)		(39		)		(98		)		(46		)
Change in estimates	67				—				67				—
Ending balance	$	208			$	202			$	208			$	202
Interest income, net (in thousands):
		Three Months Ended								Nine Months Ended
		December 31,								December 31,
		2014				2013				2014				2013
Interest income		$	362			$	519			$	1,091			$	1,389
Net realized gain on short-term investments		123				6				123				3,290
		$	485			$	525			$	1,214			$	4,679
Net loss per share:
Shares used in basic net loss per share are computed using the weighted average number of common shares outstanding during each period. Shares used in diluted net loss per share include the dilutive effect of common shares potentially issuable upon the exercise of stock options and vesting of restricted stock units ("RSUs"). The reconciliation of shares used to calculate basic and diluted net loss per share consists of the following (in thousands, except per share data):
		Three Months Ended								Nine Months Ended
		December 31,								December 31,
		2014				2013				2014				2013
Net loss		$	(12,131	)		$	(7,284	)		$	(36,913	)		$	(28,810	)
Shares used in net loss per share computation:
Weighted average common shares outstanding, basic		78,920				73,989				78,442				71,986
Net effect of dilutive common share equivalents		—				—				—				—
Weighted average common shares outstanding, diluted		78,920				73,989				78,442				71,986
Basic and diluted net loss per share		$	(0.15	)		$	(0.10	)		$	(0.47	)		$	(0.40	)
The effect of dilutive securities (comprised of options and restricted stock units) totaling 0.6 million and 0.9 million shares for the three and nine months ended December 31, 2014, respectively, and 1.8 million and 1.4 million shares for the three and nine months ended December 31, 2013, respectively, has been excluded from the diluted net loss per share computation since the Company incurred net losses in the periods presented and their effect would be antidilutive.

Restructuring_Charges

Restructuring Charges	9 Months Ended
	Dec. 31, 2014
Restructuring and Related Activities [Abstract]
RESTRUCTURING CHARGES	RESTRUCTURING CHARGES
	In April 2014, the Company implemented a plan to reorganize its operations, reduce its workforce and consolidate its facilities. The Company anticipates that this plan will reduce ongoing headcount expenses by approximately $4.6 million annually and other additional operational expenses by $0.6 million annually. In connection with this plan, the Company incurred cumulative charges of approximately $1.3 million, of which $0.2 million was incurred during the three months ended December 31, 2014. As of December 31, 2014, the Company completed this plan.
	The related activity during the nine months ended December 31, 2014 is as follows (in thousands):
		Workforce Reduction			Operating Lease		Other			Total
					Commitments
	Liability, March 31, 2014	$	—		$	—	$	—		$	—
	Restructuring charges	1,101			126		95			1,322
	Cash payments	(1,101		)	—		(1		)	(1,102		)
	Non-cash items				$	20	$	(34	)	$	(14	)
	Liability, December 31, 2014	$	—		$	146	$	60		$	206

Veloce

Veloce	9 Months Ended
	Dec. 31, 2014
Variable Interest Entity, Measure of Activity [Abstract]
VELOCE	VELOCE
	On June 20, 2012, the Company completed its acquisition of Veloce. Veloce has been developing specific ARM-based technology for the Company.
	The total estimated purchase price consideration to be paid for Veloce is approximately $178.5 million based on the benchmarks achieved during product simulations. Veloce completed all three performance milestones relating to the project as of March 31, 2014. The consideration relating to the three performance milestones, excluding the value allocated to Veloce stock equivalents that have not yet been allocated to individuals ("Unallocated Veloce Units"), in the amount of $176.4 million, has been recognized as research and development expense through December 31, 2014 compared to $169.3 million as of December 31, 2013. During the three and nine months ended December 31, 2014, the Company paid approximately $1.5 million and $9.0 million, respectively, in cash and issued approximately 39,000 shares and 0.1 million shares, of common stock, respectively, valued at approximately $0.3 million and $0.9 million, respectively, as part of the Veloce acquisition consideration. During the three and nine months ended December 31, 2013, the Company paid approximately $1.2 million and $45.4 million, respectively, in cash and issued approximately 25,000 shares and 3.8 million shares, of common stock, respectively, valued at approximately $0.2 million and $29.2 million, respectively, as part of the Veloce acquisition consideration. The Company is contractually required to distribute all Unallocated Veloce Units within a certain time period. No Unallocated Veloce Units were distributed in the three months ended December 31, 2014. During the nine months ended December 31, 2014, the Company distributed 0.5 million Unallocated Veloce Units which had a related expense of $7.1 million. Former Veloce equity holders subject to vesting requirements will receive their distribution upon satisfaction of such vesting requirements.
	For accounting purposes, the costs incurred in connection with the development milestones relating to Veloce are considered compensatory and are recognized as R&D expense. These costs are recognized in the Condensed Consolidated Statement of Operations under R&D expense in the periods when certain development and performance milestones became probable of achievement and were deemed earned. However, the value allocated to the Unallocated Veloce Units will not be recognized as R&D expense until distribution of the underlying units occurs. As of December 31, 2014, 0.1 million Unallocated Veloce Units had not been allocated, and the maximum potential additional expense to be recognized associated with these Unallocated Veloce Units is approximately $2.1 million.
	Total R&D expenses recognized related to Veloce were zero and approximately $7.1 million during the three and nine months ended December 31, 2014, respectively, and approximately $2.9 million and $42.7 million during the three and nine months ended December 31, 2013, respectively. Veloce consideration that has been accrued as of December 31, 2014 is classified as long-term if payments of the consideration are expected to occur beyond a 12 month period. For additional information regarding Veloce, see Note 4, Veloce, to the Consolidated Financial Statements included in the Company’s Annual Report on Form 10-K for the fiscal year ended March 31, 2014.

Stockholders_Equity

Stockholders' Equity	9 Months Ended
	Dec. 31, 2014
Equity [Abstract]
STOCKHOLDERS' EQUITY	STOCKHOLDERS’ EQUITY
	Stock Options
	The Company has granted stock options to employees and non-employee directors under several plans. These option plans include two stockholder-approved plans (1992 Stock Option Plan and 2011 Equity Incentive Plan) and one plan not approved by stockholders (2000 Equity Incentive Plan). Certain other outstanding options were assumed through the Company’s various acquisitions.
	A summary of the Company's stock option activity and related information during the nine months ended December 31, 2014 is as follows:
			Number of Shares (thousands)		Weighted		Weighted-Average Remaining Contractual Term (years)	Aggregate Intrinsic Value (millions)
					Average
					Exercise
					Price Per Share
	Outstanding at the beginning of the year		2,409		$	10.06
	Granted		—		—
	Exercised		(54	)	6.32			$	0.2	(1	)
	Cancelled		(473	)	13.22
	Outstanding at the end of the period		1,882		$	9.37	2	$	0.1	(2	)
	Vested and expected to vest at the end of the period		1,882		$	9.37	2	$	0.1	(2	)
	Vested and exercisable at the end of the period		1,882		$	9.37	2	$	0.1	(2	)
	(1) The aggregate pre-tax intrinsic value is calculated as the difference between the market value on the date of exercise and the exercise price of the shares.
	(2) The aggregate pre-tax intrinsic value is calculated as the difference between the market value as of the end of the third quarter 2014 and the exercise price of the shares. The closing price of the Company’s common stock was $6.52 per share on December 31, 2014.
	Restricted Stock Units ("RSUs")
	The Company has granted RSUs to employees and non-employee directors pursuant to its 1992 Plan and 2011 Equity Incentive Plan. RSUs are share awards that, upon vesting, will deliver to the holder shares of the Company’s common stock. Generally, RSUs vest ratably on a quarterly basis over four years from the date of grant. For new employees hired, RSUs will generally vest on a quarterly basis over four years provided that no shares will vest during the first year of employment, at the end of which the shares that would have vested during that year will vest and the remaining shares will vest over the remaining 12 quarters.
	In November 2013, Dr. Gopi was awarded 500,000 RSUs of which 200,000 RSUs were vested on the grant date and the remaining 300,000 RSUs will vest upon the attainment of certain specified X-GeneTM and X-Weave® product commercialization goals. The grant-date fair value of these 300,000 performance-based RSUs was $3.3 million.
	In May and November 2013 and May and October 2014, the Compensation Committee (the "Committee") authorized market-performance based RSUs ("MSUs"). The MSUs will be earned, if at all, based on the Company's Total Shareholder Return (“TSR”) compared to that of the SPDR S&P Semiconductor Index ("Index”) over a two-year performance period for half of the MSU award and a three-year performance period for the remaining half of the MSU award. The MSUs will vest between ranges of 0% and 150% based on the Company's relative TSR compared to the Index. Total grant-date fair value of these MSUs was $4.5 million.
	In May 2014, the Committee authorized an annual incentive compensation plan with respect to fiscal 2015 (the “FY2015 Short-Term Incentive Plan”). The FY2015 Short-Term Incentive Plan will pay-out based on our actual performance as measured against two equally weighted financial measures: revenue and non-GAAP earnings per share. Non-GAAP net income (loss) is derived by excluding from net income (loss) the following items required by GAAP: stock-based compensation charges, amortization of purchased intangible assets, Veloce acquisition consideration, restructuring charges, impairment of marketable securities and cost method investments, income taxes effect due to reconciling items, and other one-time and/or non-cash items. Non-GAAP earnings per share is derived by dividing non-GAAP net income (loss) by the weighted average number of common shares outstanding during the applicable periods. The award payouts for each corporate financial measure range from 50% to 150% of the pre-established target level based on the Company's actual performance for fiscal 2015. Awards under the FY2015 Short-Term Incentive Plan will be payable, if at all, in fully vested shares of common stock on or about May 15, 2015.
	RSU activity during the nine months ended December 31, 2014 is set forth below (in thousands):
		Number of Shares
	Outstanding at the beginning of the year	6,105
	Awarded	3,352
	Vested	(1,279	)
	Cancelled	(3,536	)
	Outstanding at the end of the period	4,642
	The weighted average remaining contractual term for the RSUs outstanding as of December 31, 2014 was 1.3 years.
	As of December 31, 2014, the aggregate pre-tax intrinsic value of RSUs outstanding was $30.3 million which includes performance-based awards which are subject to milestone attainment. The aggregate pretax intrinsic values were calculated based on the closing price of the Company’s common stock of $6.52 on December 31, 2014.
	The aggregate pre-tax intrinsic value of RSUs released during the nine months ended December 31, 2014 was $9.8 million. This intrinsic value represents the fair market value of the Company’s common stock on the date of release.
	Employee Stock Purchase Plan
	Under the Company's 2012 Employee Stock Purchase Plan, or ESPP, the Company reserved 1.8 million shares for issuance. In August 2014, the Company’s stockholders approved the proposal to reserve an additional 2.0 million shares under the ESPP. Under the terms of the ESPP, eligible employees are entitled to purchase common stock, on a semi-annual basis, at a purchase price equal to 85% of the fair market value of the common stock on the first or last day of the offering period, whichever is lower. During the nine months ended December 31, 2014 and 2013, 0.2 million and 0.3 million shares were issued under the ESPP, respectively. At December 31, 2014, 2.3 million shares were available for future issuance under the ESPP.

StockBased_Compensation

Stock-Based Compensation	9 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
STOCK-BASED COMPENSATION	STOCK-BASED COMPENSATION
	Stock-based compensation cost is measured at the grant date based on the fair value of the award. The Company uses the Black-Scholes model to value stock-based compensation for options and employee stock purchase rights under the ESPP, and the fair market value of the Company's common stock for RSUs. The MSUs were valued using the Monte Carlo pricing model, which uses the Company's stock price, the Index value, expected volatilities of the Company's stock price and the Index, correlation coefficients and risk free interest rates to determine the fair value. The Black-Scholes model determines the fair value of share-based payment awards based on assumptions including the Company’s stock price on the date of grant, volatility over the term of the awards, actual and projected employee stock option exercise behaviors and risk free interest rate.
	The Company did not grant options or employee stock purchase rights during the three months ended December 31, 2014 and 2013. The fair values of the options and employee stock purchase rights granted during the nine months ended December 31, 2014 and 2013 are estimated as of the grant date using the Black-Scholes option-pricing model with the following weighted-average assumptions:
		Options						Employee Stock Purchase Rights
		Nine months ended December 31,						Nine months ended December 31,
		2014		2013				2014				2013
	Expected life (years)	*		4.4				0.5				0.5
	Risk-free interest rate	*		0.6		%		0.1		%		0.1		%
	Volatility	*		49		%		57		%		57		%
	Dividend yield	*		—		%		—		%		—		%
	Weighted average fair value	*		$	2.95			$	2.57			$	3.67
	* The Company did not grant options during the nine months ended December 31, 2014.
	The weighted average grant-date fair value per share of the RSUs awarded was $5.82 and $8.20 during the three and nine months ended December 31, 2014, respectively, compared to $9.84 and $8.57 during the three and nine months ended December 31, 2013, respectively. The weighted average grant-date fair value per share was calculated based on the fair market value of the Company’s common stock on the respective grant dates.
	During the fourth quarter of fiscal 2014, the Company revised its estimated forfeiture rate used in determining the amount of stock-based compensation from 6.7% to 5.8% as a result of a decreasing rate of forfeitures in recent periods, which the Company believes is indicative of the rate it will experience during the remaining vesting period of currently outstanding unvested grants.
	The following table summarizes stock-based compensation expense related to stock options and RSUs (in thousands):
			Three Months Ended							Nine Months Ended
			December 31,							December 31,
			2014				2013			2014				2013
	Stock-based compensation expense by type of grant:
	Stock options		$	454			$	648		$	1,160			$	1,987
	RSUs		4,428				5,231			13,148				11,454
			4,882				5,879			14,308				13,441
	Stock-based compensation expensed from (capitalized to) inventory		(25		)		3			(5		)		(11		)
	Total stock-based compensation expense		$	4,857			$	5,882		$	14,303			$	13,430
	The following table summarizes stock-based compensation expense as it relates to the Company’s Condensed Consolidated Statement of Operations (in thousands):
			Three Months Ended								Nine Months Ended
			December 31,								December 31,
			2014				2013				2014				2013
	Stock-based compensation expense by cost centers:
	Cost of revenues		$	97			$	118			$	226			$	353
	Research and development		2,992				1,545				9,039				4,867
	Selling, general and administrative		1,793				4,216				5,043				8,221
			$	4,882			$	5,879			$	14,308			$	13,441
	Stock-based compensation expensed from (capitalized to) inventory		(25		)		3				(5		)		(11		)
	Total stock-based compensation expense		$	4,857			$	5,882			$	14,303			$	13,430
	As of December 31, 2014, the amount of unrecognized stock-based compensation cost, net of estimated forfeitures, related to unvested stock options and unvested RSUs was $29.8 million which will be recognized over a weighted average period of 2.3 years.

Commitments_and_Contingencies

Commitments and Contingencies	9 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES
	Commitments
	The following table summarizes the Company's contractual operating leases and other purchase commitments as of December 31, 2014 (in thousands):
	Fiscal Years Ending March 31,	Operating		-1	Purchase		-2	Total
		Leases			Commitments
	2015 (remainder of year)	$	616		$	16,909		$	17,525
	2016	1,528			13,368			14,896
	2017	1,093			3,241			4,334
	2018	632			2,833			3,465
	Total minimum payments	$	3,869		$	36,351		$	40,220
	(1) Includes the Company's headquarters building lease which expires in August 2015, subject to our right to terminate early upon at least 120 days’ notice.
	(2) Includes open purchase orders with terms that generally allow us the option to cancel or reschedule the order, subject to various restrictions and limitations. Also includes the licensing fees relating to the Company's R&D efforts, including licensed intellectual property, or IP, technology, product design, test and verification tools, of $21.1 million.
	Legal Proceedings
	The Company is currently a party to certain legal proceedings, including those noted in this section. While the Company presently believes that the ultimate outcome of these proceedings, individually and in the aggregate, will not materially harm the Company's financial position, results of operations or cash flows, legal proceedings are subject to inherent uncertainties, unfavorable rulings or other events that could occur. In addition, legal proceedings are expensive to prosecute and defend against and can divert management attention and Company resources away from the Company's business objectives. Unfavorable resolutions could include monetary damages against the Company or injunctions or other restrictions on the conduct of the Company’s business, or preclude the Company from recovering the damages it seeks in legal proceedings it has commenced. It is also possible that the Company could conclude it is in the best interests of its stockholders, employees, and customers to settle one or more such matters, and any such settlement could include substantial payments or the surrender of rights to collect payments from third parties. However, the Company has not reached this conclusion with respect to any material matter at this time.
	In 1993, the Company was named as a Potentially Responsible Party (“PRP”) along with more than 100 other companies that used an Omega Chemical Corporation waste treatment facility in Whittier, California (the “Omega Site”). The U.S. Environmental Protection Agency (“EPA”) has alleged that Omega failed to properly treat and dispose of certain hazardous waste materials at the Omega Site. The Company is a member of a large group of PRPs, known as the Omega Chemical Site PRP Organized Group (“OPOG”), that has agreed to fund certain on-going remediation efforts at the Omega Site. In February 2001, the U.S. District Court for the Central District of California (the “Court”) approved a consent decree between EPA and OPOG to study the contamination and evaluate cleanup options at the Omega Site (the Operable Unit 1 or “OU1”). In January 2009, the Court approved two amendments to the consent decree, the first expanding the scope of work to mitigate volatile organic compounds affecting indoor air quality near the Omega Site (the Operable Unit 3 or “OU3”) and the second adding settling parties to the consent decree. Removal of waste materials from the Omega Site has been completed. As part of OU1 and OU3, efforts to remediate the soil and groundwater at the Omega Site, as well as the extraction of chemical vapors from the soil and improving indoor air quality in and around the site, are underway and are expected to be ongoing for several years. In addition, OPOG and EPA are investigating a regional groundwater contamination plume allegedly originating at the Omega Site (the Operable Unit 2 or “OU2”). In September 2011, EPA issued an interim Record of Decision specifying the interim clean-up actions EPA has chosen for OU2, and in September 2012, it issued a special notice letter that triggered the commencement of good faith settlement negotiations with OPOG. In November 2014, EPA submitted a term sheet, accepted by OPOG in December 2014, describing the settlement terms and remediation actions for OU2 that will be set forth in a final consent decree to be filed with the Court. It is anticipated that EPA and OPOG will finalize the remediation consent decree in fiscal year 2016. In December 2013, OPOG retained legal counsel to pursue claims against other PRPs for the regional groundwater contamination and, in December 2014, OPOG retained legal counsel to protect its interests in connection with the bankruptcy proceedings filed by an OPOG member. In November 2007, Angeles Chemical Company, located downstream from the Omega Site, filed a lawsuit (the “Angeles Litigation”) in the Court against OPOG and the PRPs for cost recovery and indemnification for future response costs allegedly resulting from the regional groundwater contamination plume described above. In March 2008, the Court granted OPOG’s motion to stay the Angeles Litigation pending EPA’s determination of how to investigate and remediate the regional groundwater. In January 2012, as a result of challenges made by certain PRPs to the criteria previously used to allocate liability among OPOG members, and of the departure of certain PRPs from OPOG, OPOG approved changes to the cost allocation structure that resulted in an increase to the Company’s proportional allocation of liability. In addition, the subsequent departure or bankruptcy of one or more other PRPs from OPOG could have the effect of increasing the proportional liability of the remaining PRPs, including the Company. Although the Company considers a loss relating to the Omega Site probable, its share of any financial obligations for the remediation of the Omega Site, including taking into account the allocation increases described above, is not currently believed to be material to the Company’s financial statements, based on the Company’s approximately 0.5% contribution to the total waste tonnage sent to the site and current estimates of the potential remediation costs. Based on currently available information, the Company has a loss accrual that is not material and believes that the actual amount of its costs will not be materially different from the amount accrued. However, proceedings are ongoing and the eventual outcome of the clean-up efforts and the pending litigation matters is uncertain at this time. Based on currently available information, the Company does not believe that any eventual outcome will have a material adverse effect on its operations.

Sale_of_TPack_AS

Sale of TPack A/S	9 Months Ended
	Dec. 31, 2014
Discontinued Operations and Disposal Groups [Abstract]
SALE OF TPACK A/S	SALE OF TPACK A/S
	On April 22, 2013, the Company completed the sale of its subsidiary, TPack, and certain intellectual property assets owned by the Company related to TPack's business for an aggregate consideration of $33.5 million, net of working capital adjustments, payable in cash. For additional information regarding this sale, see Note 12, Sale of TPack A/S, to the Consolidated Financial Statements included in the Company’s Annual Report on Form 10-K for the fiscal year ended March 31, 2014.

Subsequent_Events_Subsequent_E

Subsequent Events Subsequent Events	9 Months Ended
	Dec. 31, 2014
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENT
	On January 23, 2015, the board of directors of the Company approved a restructuring plan to reorganize the Company’s operations and reduce its workforce and related operating expenses. The restructuring plan is intended to increase the Company’s operating efficiencies, improve its business unit alignment and help consolidate its global operating sites. The plan includes eliminating job redundancies, including some currently unfilled positions, and reducing the Company’s current workforce by approximately 40 employees, or approximately 7%. As of the date of the filing of this Quarterly Report on Form 10-Q, the Company has initiated the reduction in its workforce. The Company expects to incur cash expenditures for employee severances of approximately $1.5 million to $1.7 million, payable primarily during the current fiscal year ending March 31, 2015, and expects to incur additional non-cash charges related to the restructuring plan. The Company anticipates that the restructuring plan will reduce its ongoing net operating expenses by approximately $14.0 million to $18.0 million annually.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation
	The Condensed Consolidated Financial Statements include all the accounts of Applied Micro Circuits Corporation (the "Company") and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.
	In management’s opinion, the unaudited Condensed Consolidated Financial Statements reflect all adjustments (consisting only of normal recurring adjustments) necessary to fairly present the Company's financial position, results of operations and cash flows. Interim period operating results do not necessarily indicate the results that may be expected for any other interim period or for the full fiscal year. The Condensed Consolidated Balance Sheet as of March 31, 2014 has been derived from the audited Consolidated Financial Statements as of that date but does not include all disclosures required by U.S. generally accepted accounting principles, or GAAP. These financial statements and accompanying notes should be read in conjunction with the Consolidated Financial Statements and notes thereto in the Company's Annual Report on Form 10-K for the fiscal year ended March 31, 2014.
Use of Estimates	Use of Estimates
	The preparation of financial statements in accordance with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and the reported amounts of net revenue and expenses in the reporting period. The Company regularly evaluates estimates and assumptions related to its:
	•	capitalized mask sets including their useful lives, which affect cost of goods sold and property and equipment or Research and Development ("R&D") expenses, if not capitalized;
	•	inventory valuation, warranty liabilities and revenue reserves, which affect cost of sales, gross margin, and revenues;
	•	allowance for doubtful accounts, which affects operating expenses;
	•	unrealized losses or other-than-temporary impairments of short-term investments available for sale, which affect interest income (expense), net;
	•	valuation of other long-lived assets and goodwill, which affects depreciation and impairment of long-lived assets, impairment of goodwill and apportionment of goodwill related to divestitures;
	•	valuation of cost method investments, which affects impairment of strategic investments;
	•	potential costs of litigation, which affect operating expenses;
	•	valuation of deferred income taxes, which affects income tax expense (benefit); and
	•	stock-based compensation, which affects gross margin and operating expenses.
	The Company bases its estimates and assumptions on historical experience and on various other factors that it believes to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. The actual results experienced by the Company may differ materially and adversely from management’s estimates. To the extent there are material differences between the estimates and actual results, future results of operations will be affected.
New Accounting Pronouncements	New Accounting Pronouncements
	In May 2014, the Financial Accounting Standards Board ("FASB") issued Accounting Standard Update ("ASU") No. 2014-09, "Revenue from Contracts with Customers", which will supersede most of the existing revenue recognition guidance under U.S. GAAP. This ASU requires an entity to recognize revenue when it transfers 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. This pronouncement is effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early adoption is not permitted. The ASU allows for either full retrospective or modified retrospective adoption. The Company is currently evaluating the potential effect of this ASU on its financial statements and related disclosures.

Certain_Financial_Statement_In1

Certain Financial Statement Information (Tables)	9 Months Ended
	Dec. 31, 2014
Certain Financial Statement Information [Abstract]
Schedule of Accounts receivable	Accounts receivable, net:
			December 31,				March 31,
			2014				2014
			(In thousands)
	Accounts receivable		$	19,612			$	25,629
	Less: allowance for bad debts		(365		)		(451		)
			$	19,247			$	25,178
Schedule of Inventories	Inventories:
			December 31,				March 31,
			2014				2014
			(In thousands)
	Finished goods		$	16,618			$	9,375
	Work in process		6,494				6,510
	Raw materials		1,110				3,061
			$	24,222			$	18,946
Schedule of Other current assets	Other current assets:
			December 31,				March 31,
			2014				2014
			(In thousands)
	Prepaid expenses		$	12,843			$	10,978
	Executive deferred compensation assets		1,108				1,035
	Proceeds receivable from sale of strategic investment		—				3,353
	Other		1,252				1,433
			$	15,203			$	16,799
Schedule of Property and equipment	Property and equipment:
			Useful		December 31,				March 31,
			Life		2014				2014
			(In years)		(In thousands)
	Machinery and equipment*		5-Mar		$	39,520			$	44,503
	Leasehold improvements		5-Jan		10,473				11,574
	Computers, office furniture and equipment*		5-Mar		44,581				43,365
					94,574				99,442
	Less: accumulated depreciation and amortization*				(73,628		)		(78,696		)
					$	20,946			$	20,746
Schedule of Goodwill	Goodwill is as follows:
		December 31,				March 31,
		2014				2014
		(In thousands)
	Goodwill	$	11,425			$	11,425
Schedule of Purchased intangible assets	Purchase-related intangibles are as follows:
			31-Dec-14														31-Mar-14
			Gross				Accumulated				Net				Weighted		Gross				Accumulated				Net				Weighted
							Amortization								average						Amortization								average
							and Impairments								remaining						and Impairments								remaining
															useful life														useful life
			(In thousands)												(In years)		(In thousands)												(In years)
	Developed technology/in-process research and development		$	425,000			$	(425,000	)		$	—			0		$	425,000			$	(425,000	)		$	—			0
	Customer relationships		6,330				(6,330		)		—				0		6,330				(6,225		)		105				0.4
	Patents/core technology rights/trade name		62,306				(62,306		)		—				0		62,306				(62,306		)		—				0
			$	493,636			$	(493,636	)		$	—					$	493,636			$	(493,531	)		$	105
Schedule of Other assets	Other assets:
			December 31,				March 31,
			2014				2014
			(In thousands)
	Non-current portion of prepaid expenses		$	2,957			$	4,235
	Strategic investments*		500				3,000
	Other		519				519
			$	3,976			$	7,754
Schedule of Other accrued liabilities	Other accrued liabilities:
			December 31,				March 31,
			2014				2014
			(In thousands)
	Employee related liabilities		$	1,622			$	1,733
	Executive deferred compensation		1,385				1,314
	Income taxes		1,870				962
	Professional fees		755				1,259
	Other		3,027				5,609
			$	8,659			$	10,877
Schedule of Cash, cash equivalents and available-for-sale investments by type of instruments	Short-term investments:
	The following is a summary of cash, cash equivalents and available-for-sale investments by type of instrument (in thousands):
			31-Dec-14																31-Mar-14
			Amortized				Gross Unrealized								Estimated				Amortized				Gross Unrealized							Estimated
			Cost				Gains				Losses				Fair Value				Cost				Gains				Losses			Fair Value
	Cash		$	40,828			$	—			$	—			$	40,828			$	65,867			$	—			$	—		$	65,867
	Cash equivalents		9,252				—				—				9,252				5,672				—				—			5,672
	U.S. Treasury securities and agency bonds		1,475				—				—				1,475				2,838				—				—			2,838
	Corporate bonds		10,911				14				(9		)		10,916				10,599				30				(2		)	10,627
	Mortgage-backed and asset-backed securities*		1,614				291				(2		)		1,903				1,793				297				(16		)	2,074
	Closed-end bond funds		13,249				2,248				(206		)		15,291				14,373				2,392				(402		)	16,363
	Preferred stock		2,406				952				—				3,358				2,406				736				—			3,142
			$	79,735			$	3,505			$	(217	)		$	83,023			$	103,548			$	3,455			$	(420	)	$	106,583
	Reported as:
	Cash and cash equivalents														$	50,080														$	71,539
	Short-term investments available-for-sale														32,943															35,044
															$	83,023														$	106,583
	* At December 31, 2014 and March 31, 2014, approximately $1.0 million and $1.1 million of the estimated fair value presented were mortgage-backed securities, respectively.
Schedule of Cash, cash equivalents and available-for-sale investments by type of instruments measured at fair value on recurring basis	The following is a summary of cash, cash equivalents and available-for-sale investments by type of instrument measured at fair value on a recurring basis (in thousands):
			31-Dec-14																31-Mar-14
			Level 1				Level 2				Level 3				Total				Level 1				Level 2				Level 3			Total
	Cash		$	40,828			$	—			$	—			$	40,828			$	65,867			$	—			$	—		$	65,867
	Cash equivalents		9,252				—				—				9,252				5,672				—				—			5,672
	U.S. Treasury securities and agency bonds		1,475				—				—				1,475				2,838				—				—			2,838
	Corporate bonds		—				10,916				—				10,916				—				10,627				—			10,627
	Mortgage-backed and asset-backed securities		—				1,903				—				1,903				—				2,074				—			2,074
	Closed-end bond funds		15,291				—				—				15,291				16,363				—				—			16,363
	Preferred stock		—				3,358				—				3,358				—				3,142				—			3,142
			$	66,846			$	16,177			$	—			$	83,023			$	90,740			$	15,843			$	—		$	106,583
Schedule of Cost and estimated fair values of available-for-sale securities with stated maturities by contractual maturity	The following is a summary of the cost and estimated fair values of available-for-sale securities with stated maturities, which include U.S. Treasury securities and agency bonds, corporate bonds and mortgage-backed and asset-backed securities, by contractual maturity (in thousands):
			31-Dec-14
			Cost				Estimated Fair Value
	Less than 1 year		$	5,745			$	5,837
	Mature in 1 – 2 years		7,147				7,170
	Mature in 3 – 5 years		291				305
	Mature after 5 years		817				982
			$	14,000			$	14,294
Schedule of Gross unrealized losses	The following is a summary of gross unrealized losses (in thousands):
			Less Than 12 Months of								12 Months or More of								Total
			Unrealized Losses								Unrealized Losses
	As of December 31, 2014		Estimated				Gross				Estimated				Gross				Estimated				Gross
			Fair				Unrealized				Fair				Unrealized				Fair				Unrealized
			Value				Losses				Value				Losses				Value				Losses
	Corporate bonds		$	3,750			$	(9	)		$	—			$	—			$	3,750			$	(9	)
	Mortgage-backed and asset-backed securities		275				(2		)		121								396				(2		)
	Closed-end bond funds		61				(2		)		4,255				(204		)		4,316				(206		)
			$	4,086			$	(13	)		$	4,376			$	(204	)		$	8,462			$	(217	)
			Less Than 12 Months of								12 Months or More of								Total
			Unrealized Losses								Unrealized Losses
	As of March 31, 2014		Estimated				Gross				Estimated				Gross				Estimated				Gross
			Fair				Unrealized				Fair				Unrealized				Fair				Unrealized
			Value				Losses				Value				Losses				Value				Losses
	Corporate bonds		$	992			$	(2	)		$	—			$	—			$	992			$	(2	)
	Mortgage-backed and asset-backed securities		431				(16		)		—				—				431				(16		)
	Closed-end bond funds		4,819				(333		)		405				(69		)		5,224				(402		)
			$	6,242			$	(351	)		$	405			$	(69	)		$	6,647			$	(420	)
Schedule of Warranty reserve activity	The following table summarizes warranty reserve activity (in thousands):
		Three Months Ended								Nine Months Ended
		December 31,								December 31,
		2014				2013				2014				2013
	Beginning balance	$	175			$	187			$	199			$	220
	Additions during the period	41				54				40				28
	Settlements and expirations	(75		)		(39		)		(98		)		(46		)
	Change in estimates	67				—				67				—
	Ending balance	$	208			$	202			$	208			$	202
Schedule of Interest income, net	Interest income, net (in thousands):
			Three Months Ended								Nine Months Ended
			December 31,								December 31,
			2014				2013				2014				2013
	Interest income		$	362			$	519			$	1,091			$	1,389
	Net realized gain on short-term investments		123				6				123				3,290
			$	485			$	525			$	1,214			$	4,679
Schedule of Reconciliation of shares used to calculate basic and diluted net loss per share	The reconciliation of shares used to calculate basic and diluted net loss per share consists of the following (in thousands, except per share data):
			Three Months Ended								Nine Months Ended
			December 31,								December 31,
			2014				2013				2014				2013
	Net loss		$	(12,131	)		$	(7,284	)		$	(36,913	)		$	(28,810	)
	Shares used in net loss per share computation:
	Weighted average common shares outstanding, basic		78,920				73,989				78,442				71,986
	Net effect of dilutive common share equivalents		—				—				—				—
	Weighted average common shares outstanding, diluted		78,920				73,989				78,442				71,986
	Basic and diluted net loss per share		$	(0.15	)		$	(0.10	)		$	(0.47	)		$	(0.40	)

Restructuring_Charges_Tables

Restructuring Charges (Tables)	9 Months Ended
	Dec. 31, 2014
Restructuring and Related Activities [Abstract]
Schedule of restructuring activity	The related activity during the nine months ended December 31, 2014 is as follows (in thousands):
		Workforce Reduction			Operating Lease		Other			Total
					Commitments
	Liability, March 31, 2014	$	—		$	—	$	—		$	—
	Restructuring charges	1,101			126		95			1,322
	Cash payments	(1,101		)	—		(1		)	(1,102		)
	Non-cash items				$	20	$	(34	)	$	(14	)
	Liability, December 31, 2014	$	—		$	146	$	60		$	206

Stockholders_Equity_Tables

Stockholders' Equity (Tables)	9 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Schedule of Option Activity Under Stock Incentive Plans	A summary of the Company's stock option activity and related information during the nine months ended December 31, 2014 is as follows:
			Number of Shares (thousands)		Weighted		Weighted-Average Remaining Contractual Term (years)	Aggregate Intrinsic Value (millions)
					Average
					Exercise
					Price Per Share
	Outstanding at the beginning of the year		2,409		$	10.06
	Granted		—		—
	Exercised		(54	)	6.32			$	0.2	(1	)
	Cancelled		(473	)	13.22
	Outstanding at the end of the period		1,882		$	9.37	2	$	0.1	(2	)
	Vested and expected to vest at the end of the period		1,882		$	9.37	2	$	0.1	(2	)
	Vested and exercisable at the end of the period		1,882		$	9.37	2	$	0.1	(2	)
Schedule of Restricted Stock Unit Activity	RSU activity during the nine months ended December 31, 2014 is set forth below (in thousands):
		Number of Shares
	Outstanding at the beginning of the year	6,105
	Awarded	3,352
	Vested	(1,279	)
	Cancelled	(3,536	)
	Outstanding at the end of the period	4,642

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	9 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Assumptions Used	The Company did not grant options or employee stock purchase rights during the three months ended December 31, 2014 and 2013. The fair values of the options and employee stock purchase rights granted during the nine months ended December 31, 2014 and 2013 are estimated as of the grant date using the Black-Scholes option-pricing model with the following weighted-average assumptions:
		Options						Employee Stock Purchase Rights
		Nine months ended December 31,						Nine months ended December 31,
		2014		2013				2014				2013
	Expected life (years)	*		4.4				0.5				0.5
	Risk-free interest rate	*		0.6		%		0.1		%		0.1		%
	Volatility	*		49		%		57		%		57		%
	Dividend yield	*		—		%		—		%		—		%
	Weighted average fair value	*		$	2.95			$	2.57			$	3.67
	* The Company did not grant options during the nine months ended December 31, 2014.
Summary of Stock-Based Compensation Expense of Stock Options and Restricted Stock Units	The following table summarizes stock-based compensation expense related to stock options and RSUs (in thousands):
			Three Months Ended							Nine Months Ended
			December 31,							December 31,
			2014				2013			2014				2013
	Stock-based compensation expense by type of grant:
	Stock options		$	454			$	648		$	1,160			$	1,987
	RSUs		4,428				5,231			13,148				11,454
			4,882				5,879			14,308				13,441
	Stock-based compensation expensed from (capitalized to) inventory		(25		)		3			(5		)		(11		)
	Total stock-based compensation expense		$	4,857			$	5,882		$	14,303			$	13,430
Summary of Stock-Based Compensation Expense	The following table summarizes stock-based compensation expense as it relates to the Company’s Condensed Consolidated Statement of Operations (in thousands):
			Three Months Ended								Nine Months Ended
			December 31,								December 31,
			2014				2013				2014				2013
	Stock-based compensation expense by cost centers:
	Cost of revenues		$	97			$	118			$	226			$	353
	Research and development		2,992				1,545				9,039				4,867
	Selling, general and administrative		1,793				4,216				5,043				8,221
			$	4,882			$	5,879			$	14,308			$	13,441
	Stock-based compensation expensed from (capitalized to) inventory		(25		)		3				(5		)		(11		)
	Total stock-based compensation expense		$	4,857			$	5,882			$	14,303			$	13,430

Commitments_and_Contingencies_

Commitments and Contingencies Commitments and Contingencies (Tables)	9 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Schedule of Contractual Obligation by Fiscal Year Maturity	The following table summarizes the Company's contractual operating leases and other purchase commitments as of December 31, 2014 (in thousands):
	Fiscal Years Ending March 31,	Operating		-1	Purchase		-2	Total
		Leases			Commitments
	2015 (remainder of year)	$	616		$	16,909		$	17,525
	2016	1,528			13,368			14,896
	2017	1,093			3,241			4,334
	2018	632			2,833			3,465
	Total minimum payments	$	3,869		$	36,351		$	40,220
	(1) Includes the Company's headquarters building lease which expires in August 2015, subject to our right to terminate early upon at least 120 days’ notice.
	(2) Includes open purchase orders with terms that generally allow us the option to cancel or reschedule the order, subject to various restrictions and limitations. Also includes the licensing fees relating to the Company's R&D efforts, including licensed intellectual property, or IP, technology, product design, test and verification tools, of $21.1 million.

Certain_Financial_Statement_In2

Certain Financial Statement Information Accounts Receivable (Details) (USD $)	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Schedule of Accounts receivable
Accounts receivable	$19,612	$25,629
Less: allowance for bad debts	-365	-451
Accounts receivable, net	$19,247	$25,178

Certain_Financial_Statement_In3

Certain Financial Statement Information Inventories (Details) (USD $)	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Schedule of Inventories
Finished goods	$16,618	$9,375
Work in process	6,494	6,510
Raw materials	1,110	3,061
Inventories, total	$24,222	$18,946

Certain_Financial_Statement_In4

Certain Financial Statement Information Other Current Assets (Details) (USD $)	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Schedule of Other current assets
Prepaid expenses	$12,843	$10,978
Executive deferred compensation assets	1,108	1,035
Proceeds receivable from sale of strategic investment	0	3,353
Other	1,252	1,433
Other current assets, total	$15,203	$16,799

Certain_Financial_Statement_In5

Certain Financial Statement Information Property and Equipment (Details) (USD $)	3 Months Ended		9 Months Ended
	Dec. 31, 2014		Dec. 31, 2014		Mar. 31, 2014
Schedule of Property and equipment
Machinery and equipment	$39,520,000		39,520,000		$44,503,000
Leasehold improvements	10,473,000		10,473,000		11,574,000
Computers, office furniture and equipment	44,581,000	[1]	44,581,000	[1]	43,365,000	[1]
Property and equipment, gross	94,574,000		94,574,000		99,442,000
Less: accumulated depreciation and amortization	-73,628,000	[1]	-73,628,000	[1]	-78,696,000	[1]
Property and equipment, net	20,946,000		20,946,000		20,746,000
Fully depreciated assets written off	$11,800,000
Machinery and Equipment [Member] | Minimum
Schedule of Property and equipment
Useful life			3 years
Machinery and Equipment [Member] | Maximum
Schedule of Property and equipment
Useful life			5 years
Leasehold Improvements [Member] | Minimum
Schedule of Property and equipment
Useful life			1 year
Leasehold Improvements [Member] | Maximum
Schedule of Property and equipment
Useful life			5 years
Computers, Office Furniture and Equipment [Member] | Minimum
Schedule of Property and equipment
Useful life			3 years
Computers, Office Furniture and Equipment [Member] | Maximum
Schedule of Property and equipment
Useful life			5 years
[1]	During the three months ended December 31, 2014, the Company wrote off fully depreciated assets with an acquired cost of $11.8 million.

Certain_Financial_Statement_In6

Certain Financial Statement Information Goodwill (Details) (USD $)	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Certain Financial Statement Information [Abstract]
Goodwill	$11,425	$11,425

Certain_Financial_Statement_In7

Certain Financial Statement Information Purchased Intangibles (Details) (USD $)	9 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Mar. 31, 2014
Schedule of Purchased Intangible assets
Gross Assets	$493,636	$493,636
Accumulated Amortization and Impairments	-493,636	-493,531
Intangible Assets, Net (Excluding Goodwill)	0	105
Developed technology/in-process research and development [Member]
Schedule of Purchased Intangible assets
Gross Assets	425,000	425,000
Accumulated Amortization and Impairments	-425,000	-425,000
Intangible Assets, Net (Excluding Goodwill)	0	0
Weighted average remaining useful life	0 years	0 years
Customer relationships [Member]
Schedule of Purchased Intangible assets
Gross Assets	6,330	6,330
Accumulated Amortization and Impairments	-6,330	-6,225
Intangible Assets, Net (Excluding Goodwill)	0	105
Weighted average remaining useful life	0 years	4 months 24 days
Patents/core technology rights/tradename [Member]
Schedule of Purchased Intangible assets
Gross Assets	62,306	62,306
Accumulated Amortization and Impairments	-62,306	-62,306
Intangible Assets, Net (Excluding Goodwill)	$0	$0
Weighted average remaining useful life	0 years	0 years

Certain_Financial_Statement_In8

Certain Financial Statement Information Other Assets (Details) (USD $)	Dec. 31, 2014		Mar. 31, 2014
In Thousands, unless otherwise specified
Schedule of other assets
Non-current portion of prepaid expenses	$2,957		$4,235
Strategic investments	500	[1]	3,000	[1]
Other	519		519
Total other assets	$3,976		$7,754
[1]	Strategic investments The Company has entered into certain equity investments in privately held businesses to achieve certain strategic business objectives. The Company’s investments in equity securities of privately held businesses are accounted for under the cost method. Under the cost method, strategic investments in which the Company holds less than a 20% voting interest and in which the Company does not have the ability to exercise significant influence are carried at cost reduced by other-than-temporary impairments, as appropriate. The Company periodically reviews these investments for other-than-temporary declines in fair value based on the specific identification method and writes down investments when an other-than-temporary decline has occurred. During the three months ended December 31, 2014 and during the three and nine months ended December 31, 2013, the Company did not record any other-than-temporary impairment charges with respect to its strategic investments. During the nine months ended December 31, 2014, the Company recorded an other-than-temporary impairment charge with respect to one of its strategic investments in the amount of $2.5 million.

Certain_Financial_Statement_In9

Certain Financial Statement Information Other Accrued Liabiliteis (Details) (USD $)	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Schedule of other accrued liabilities
Employee related liabilities	$1,622	$1,733
Executive deferred compensation	1,385	1,314
Income taxes	1,870	962
Professional fees	755	1,259
Other	3,027	5,609
Total other accrued liabilities	$8,659	$10,877

Recovered_Sheet1

Certain Financial Statement Information Short-Term Investments (Details) (USD $)	9 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Mar. 31, 2014		Dec. 31, 2013	Mar. 31, 2013
Schedule of cash, cash equivalents and available-for-sale investments by type of instruments
Available-for-sale Securities, Amortized Cost	$79,735		$103,548
Available-for-sale Securities, Gross Unrealized Gain	3,505		3,455
Available-for-sale Securities, Gross Unrealized Loss	-217		-420
Available-for-sale Securities, Estimated Fair Value	83,023		106,583
Cash and cash equivalents	50,080		71,539		23,630	19,065
Short-term investments available-for-sale	32,943		35,044
Cash, Cash equivalents and Short-term investments, Estimated Fair Value	83,023		106,583
Cash [Member]
Schedule of cash, cash equivalents and available-for-sale investments by type of instruments
Cash and Cash equivalents, Estimated Fair Value	40,828		65,867
Cash equivalents [Member]
Schedule of cash, cash equivalents and available-for-sale investments by type of instruments
Cash and Cash equivalents, Estimated Fair Value	9,252		5,672
U.S Treasury securities and agency bonds [Member]
Schedule of cash, cash equivalents and available-for-sale investments by type of instruments
Available-for-sale Securities, Amortized Cost	1,475		2,838
Available-for-sale Securities, Gross Unrealized Gain	0		0
Available-for-sale Securities, Gross Unrealized Loss	0		0
Available-for-sale Securities, Estimated Fair Value	1,475		2,838
Corporate bonds [Member]
Schedule of cash, cash equivalents and available-for-sale investments by type of instruments
Available-for-sale Securities, Amortized Cost	10,911		10,599
Available-for-sale Securities, Gross Unrealized Gain	14		30
Available-for-sale Securities, Gross Unrealized Loss	-9		-2
Available-for-sale Securities, Estimated Fair Value	10,916		10,627
Mortgage-backed and asset-backed securities [Member]
Schedule of cash, cash equivalents and available-for-sale investments by type of instruments
Available-for-sale Securities, Amortized Cost	1,614		1,793
Available-for-sale Securities, Gross Unrealized Gain	291		297
Available-for-sale Securities, Gross Unrealized Loss	-2		-16
Available-for-sale Securities, Estimated Fair Value	1,903	[1]	2,074	[1]
Closed-end bond funds [Member]
Schedule of cash, cash equivalents and available-for-sale investments by type of instruments
Available-for-sale Securities, Amortized Cost	13,249		14,373
Available-for-sale Securities, Gross Unrealized Gain	2,248		2,392
Available-for-sale Securities, Gross Unrealized Loss	-206		-402
Available-for-sale Securities, Estimated Fair Value	15,291		16,363
Preferred stock [Member]
Schedule of cash, cash equivalents and available-for-sale investments by type of instruments
Available-for-sale Securities, Amortized Cost	2,406		2,406
Available-for-sale Securities, Gross Unrealized Gain	952		736
Available-for-sale Securities, Gross Unrealized Loss	0		0
Available-for-sale Securities, Estimated Fair Value	3,358		3,142
Mortgage-backed securities [Member]
Schedule of cash, cash equivalents and available-for-sale investments by type of instruments
Cash, Cash equivalents and Short-term investments, Estimated Fair Value	$1,000	[1]	$1,100	[1]
[1]	At December 31, 2014 and March 31, 2014, approximately $1.0 million and $1.1 million of the estimated fair value presented were mortgage-backed securities, respectively.

Recovered_Sheet2

Certain Financial Statement Information Fair Value (Details) (USD $)	Dec. 31, 2014		Mar. 31, 2014
In Thousands, unless otherwise specified
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	$83,023		$106,583
Cash, cash equivalents and available-for-sale investments measured at fair value on recurring basis	83,023		106,583
Level 1 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Cash, cash equivalents and available-for-sale investments measured at fair value on recurring basis	66,846		90,740
Level 2 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Cash, cash equivalents and available-for-sale investments measured at fair value on recurring basis	16,177		15,843
Level 3 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Cash, cash equivalents and available-for-sale investments measured at fair value on recurring basis	0		0
Cash [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Cash and cash equivalents measured at fair value on a recurring basis	40,828		65,867
Cash [Member] | Level 1 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Cash and cash equivalents measured at fair value on a recurring basis	40,828		65,867
Cash [Member] | Level 2 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Cash and cash equivalents measured at fair value on a recurring basis	0		0
Cash [Member] | Level 3 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Cash and cash equivalents measured at fair value on a recurring basis	0		0
Cash equivalents [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Cash and cash equivalents measured at fair value on a recurring basis	9,252		5,672
Cash equivalents [Member] | Level 1 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Cash and cash equivalents measured at fair value on a recurring basis	9,252		5,672
Cash equivalents [Member] | Level 2 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Cash and cash equivalents measured at fair value on a recurring basis	0		0
Cash equivalents [Member] | Level 3 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Cash and cash equivalents measured at fair value on a recurring basis	0		0
U.S Treasury securities and agency bonds [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	1,475		2,838
U.S Treasury securities and agency bonds [Member] | Level 1 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	1,475		2,838
U.S Treasury securities and agency bonds [Member] | Level 2 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	0		0
U.S Treasury securities and agency bonds [Member] | Level 3 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	0		0
Corporate bonds [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	10,916		10,627
Corporate bonds [Member] | Level 1 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	0		0
Corporate bonds [Member] | Level 2 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	10,916		10,627
Corporate bonds [Member] | Level 3 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	0		0
Mortgage-backed and asset-backed securities [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	1,903	[1]	2,074	[1]
Mortgage-backed and asset-backed securities [Member] | Level 1 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	0		0
Mortgage-backed and asset-backed securities [Member] | Level 2 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	1,903		2,074
Mortgage-backed and asset-backed securities [Member] | Level 3 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	0		0
Closed-end bond funds [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	15,291		16,363
Closed-end bond funds [Member] | Level 1 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	15,291		16,363
Closed-end bond funds [Member] | Level 2 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	0		0
Closed-end bond funds [Member] | Level 3 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	0		0
Preferred stock [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	3,358		3,142
Preferred stock [Member] | Level 1 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	0		0
Preferred stock [Member] | Level 2 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	3,358		3,142
Preferred stock [Member] | Level 3 [Member]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments by Type of Instruments Measured at Fair Value on Recurring Basis
Available-for-sale securities measured at fair value on a recurring basis	$0		$0
[1]	At December 31, 2014 and March 31, 2014, approximately $1.0 million and $1.1 million of the estimated fair value presented were mortgage-backed securities, respectively.

Recovered_Sheet3

Certain Financial Statement Information Cost and Fair Value of Available-for-Sale Securities (Details) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Schedule of cost and estimated fair values of available-for-sale securities with stated maturities by contractual maturity
Less than 1 year, Cost	$5,745
Mature in 1 - 2 years, Cost	7,147
Mature in 3 - 5 years, Cost	291
Mature after 5 years, Cost	817
Cost, Total	14,000
Less than 1 year, Fair Value	5,837
Mature in 1 - 2 years, Fair Value	7,170
Mature in 3 - 5 years, Fair Value	305
Mature after 5 years, Fair Value	982
Fair Value, Total	$14,294

Recovered_Sheet4

Certain Financial Statement Information Gross Unrealized Losses (Details) (USD $)	9 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Mar. 31, 2014
Schedule of Gross Unrealized Losses
Less Than 12 Months of Unrealized Losses, Estimated Fair Value	$4,086	$6,242
Less than 12 Months of Unrealized Losses, Gross Unrealized Losses	-13	-351
12 Months or More of Unrealized Losses, Estimated Fair Value	4,376	405
12 Months or More of Unrealized Losses, Gross Unrealized Losses	-204	-69
Total, Estimated Fair Value	8,462	6,647
Total Gross Unrealized Losses	-217	-420
Corporate bonds [Member]
Schedule of Gross Unrealized Losses
Less Than 12 Months of Unrealized Losses, Estimated Fair Value	3,750	992
Less than 12 Months of Unrealized Losses, Gross Unrealized Losses	-9	-2
12 Months or More of Unrealized Losses, Estimated Fair Value	0	0
12 Months or More of Unrealized Losses, Gross Unrealized Losses	0	0
Total, Estimated Fair Value	3,750	992
Total Gross Unrealized Losses	-9	-2
Mortgage-backed and asset-backed securities [Member]
Schedule of Gross Unrealized Losses
Less Than 12 Months of Unrealized Losses, Estimated Fair Value	275	431
Less than 12 Months of Unrealized Losses, Gross Unrealized Losses	-2	-16
12 Months or More of Unrealized Losses, Estimated Fair Value	121	0
12 Months or More of Unrealized Losses, Gross Unrealized Losses		0
Total, Estimated Fair Value	396	431
Total Gross Unrealized Losses	-2	-16
Closed-end bond funds [Member]
Schedule of Gross Unrealized Losses
Less Than 12 Months of Unrealized Losses, Estimated Fair Value	61	4,819
Less than 12 Months of Unrealized Losses, Gross Unrealized Losses	-2	-333
12 Months or More of Unrealized Losses, Estimated Fair Value	4,255	405
12 Months or More of Unrealized Losses, Gross Unrealized Losses	-204	-69
Total, Estimated Fair Value	4,316	5,224
Total Gross Unrealized Losses	($206)	($402)

Recovered_Sheet5

Certain Financial Statement Information Warranty (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Schedule of Warranty Reserve Activity
Beginning balance	$175	$187	$199	$220
Additions during the period	41	54	40	28
Settlements and expirations	-75	-39	-98	-46
Additions during the period	67	0	67	0
Ending balance	$208	$202	$208	$202

Recovered_Sheet6

Certain Financial Statement Information Interest Income/Expense (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Schedule of Interest Income, Net
Interest income	$362	$519	$1,091	$1,389
Net realized gain on short-term investments	123	6	123	3,290
Interest income, net	$485	$525	$1,214	$4,679

Recovered_Sheet7

Certain Financial Statement Information Net Income/Loss Per Share (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Schedule of Reconciliation of Shares Used to Calculate Basic and Diluted Net (Loss) Income Per Share
Net loss	($12,131)	($7,284)	($36,913)	($28,810)
Shares used in net loss per share computation:
Weighted average common shares outstanding, basic (shares)	78,920	73,989	78,442	71,986
Net effect of dilutive common share equivalents (shares)	0	0	0	0
Weighted average common shares outstanding, diluted (shares)	78,920	73,989	78,442	71,986
Basic and diluted net loss per share (in Dollars per share)	($0.15)	($0.10)	($0.47)	($0.40)

Recovered_Sheet8

Certain Financial Statement Information (Details Textual) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
In Thousands, except Share data in Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Mar. 31, 2014
Certain Financial Statement Information [Line Items]
Impairment of a strategic investment	$0	$0	$2,500	$0
Gross unrealized gain			$3,505		$3,455
Options and Restricted Stock Units [Member]
Certain Financial Statement Information [Line Items]
Antidilutive securities excluded from net loss per share computation	0.6	1.8	0.9	1.4

Restructuring_Charges_Details_

Restructuring Charges (Details Textual) (USD $)	3 Months Ended		9 Months Ended		1 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Apr. 30, 2014
Restructuring Charges (Textual) [Abstract]
Restructuring charges	$221,000	$38,000	$1,322,000	$1,130,000
Workforce Reduction [Member]
Restructuring Charges (Textual) [Abstract]
Restructuring charges			1,101,000
Other Operational Expense [Member]
Restructuring Charges (Textual) [Abstract]
Restructuring charges			95,000
April 2014 Restructuring Program [Member] | Workforce Reduction [Member]
Restructuring Charges (Textual) [Abstract]
Anticipated reduction in expenses					4,600,000
April 2014 Restructuring Program [Member] | Other Operational Expense [Member]
Restructuring Charges (Textual) [Abstract]
Anticipated reduction in expenses					$600,000

Restructuring_Charges_Details_1

Restructuring Charges (Details 1) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Restructuring Reserve [Roll Forward]
Liability, beginning balance			$0
Restructuring charges	221	38	1,322	1,130
Cash payments			-1,102
Non-cash items			-14
Liability, ending balance	206		206
Workforce Reduction [Member]
Restructuring Reserve [Roll Forward]
Liability, beginning balance			0
Restructuring charges			1,101
Cash payments			-1,101
Liability, ending balance	0		0
Operating Lease Commitments [Member]
Restructuring Reserve [Roll Forward]
Liability, beginning balance			0
Restructuring charges			126
Cash payments			0
Non-cash items			20
Liability, ending balance	146		146
Other [Member]
Restructuring Reserve [Roll Forward]
Liability, beginning balance			0
Restructuring charges			95
Cash payments			-1
Non-cash items			-34
Liability, ending balance	$60		$60

Veloce_Details_Textual

Veloce (Details Textual) (Veloce Technologies Inc [Member], USD $)	3 Months Ended		9 Months Ended		18 Months Ended	30 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2014
Veloce Technologies Inc [Member]
Veloce (Textual) [Abstract]
Total consideration to be transferred		$178.50		$178.50	$178.50
Research and development expenses incurred	0	2.9	7.1	42.7	169.3	176.4
Payment of aggregate consideration as cash	1.5	1.2	9	45.4
Aggregate shares issued	39,000	0	100,000	3,800,000
Stock issued for acquisition, value	0.3	0.2	0.9	29.2
Issuance of additional units	0		500,000
Issuance of additional units, amount			7.1
Unallocated units	100,000		100,000			100,000
Unallocated units, maximum potential value	$2.10		$2.10			$2.10

Stockholders_Equity_Stock_Opti

Stockholders' Equity - Stock Options (Details) (USD $)	9 Months Ended
In Millions, except Share data in Thousands, unless otherwise specified	Dec. 31, 2014
	Approved_Plan
Equity [Abstract]
Number of stockholder-approved plans	2
Number of plans unapproved by stockholders	1
Schedule of Option Activity Under Stock Incentive Plans
Number of Shares, Outstanding at the beginning of the year	2,409
Number of Shares, Granted	0
Number of Shares, Exercised	-54
Number of Shares, Forfeited	-473
Number of Shares, Outstanding at the end of the period	1,882
Number of Shares, Vested at the end of the period	1,882
Number of Shares, Vested and exercisable at end of period	1,882
Schedule of Weighted Average Exercise Price Per Share Under Stock Incentive Plans
Weighted Average Exercise Price Per Share, Outstanding at the beginning of the year (USD per share)	$10.06
Weighted Average Exercise Price Per Share, Granted (USD per share)	$0
Weighted Average Exercise Price Per Share, Exercised (USD per share)	$6.32
Weighted Average Exercise Price Per Share, Forfeited (USD per share)	$13.22
Weighted Average Exercise Price Per Share, Outstanding at the end of the period (USD per share)	$9.37
Weighted Average Exercise Price Per Share, Vested at the end of the period (USD per share)	$9.37
Weighted Average Exercise Price Per Share, Vested and exercisable at the end of the period (USD per share)	$9.37
Aggregate pretax intrinsic value of options exercised	$0.20	[1]
Weighted average remaining contractual term for options outstanding at end of period (in years)	2 years 0 months 5 days
Aggregate intrinsic value of options outstanding at end of period	0.1	[2]
Weighted Average Remaining Contractual Life, Vested and Exercisable at Period End (in years)	2 years 0 months 5 days
Aggregate intrinsic value of options, Vested and exercisable at end of period	0.1	[2]
Weighted Average Remaining Contractual Life, Vested and expected to vest at end of period (in years)	2 years 0 months 1 day
Aggregate intrinsic value of options, Vested and expected to vest at end of period	$0.10	[2]
Common stock, closing price per share	$6.52
[1]	The aggregate pre-tax intrinsic value is calculated as the difference between the market value on the date of exercise and the exercise price of the shares.
[2]	The aggregate pre-tax intrinsic value is calculated as the difference between the market value as of the end of the third quarter 2014 and the exercise price of the shares. The closing price of the Company’s common stock was $6.52 per share on December 31, 2014.

Stockholders_Equity_Restricted

Stockholders' Equity - Restricted Stock Units (Details) (USD $)	9 Months Ended	1 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Nov. 30, 2013	31-May-13	31-May-14
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Weighted average remaining contractual term for the restricted stock units outstanding, in years	1 year 3 months 10 days
Aggregate pre-tax intrinsic value of restricted stock units outstanding which includes performance based awards which are subject to milestone attainments	$30.30
Common stock, closing price per share	$6.52
Aggregate pretax intrinsic value	9.8
Restricted Stock Units (RSUs)
Class of Stock [Line Items]
Nonvested restricted units outstanding	4,642,000
Restricted stock units awarded	3,352,000
Restricted stock units vested	1,279,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of Shares, Beginning balance	6,105,000
Number of Shares, Awarded	3,352,000
Number of Shares, Vested	-1,279,000
Number of Shares, Cancelled	-3,536,000
Number of Shares, Ending balance	4,642,000
Restricted Stock Units (RSUs) | Officer
Class of Stock [Line Items]
Restricted stock units awarded		500,000
Restricted stock units vested		200,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of Shares, Awarded		500,000
Number of Shares, Vested		-200,000
Performance Based RSU | Officer
Class of Stock [Line Items]
Nonvested restricted units outstanding	300,000
Grants in period, fair value		3.3
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of Shares, Ending balance	300,000
Performance-Based MSU
Class of Stock [Line Items]
Grants in period, fair value		4.5
Performance-Based MSU | Minimum
Class of Stock [Line Items]
Award vesting percentage		0.00%
Performance-Based MSU | Maximum
Class of Stock [Line Items]
Award vesting percentage		150.00%
Performance-Based MSU | First Vesting Period
Class of Stock [Line Items]
Award performance period			2 years
Performance-Based MSU | Second Vesting Period
Class of Stock [Line Items]
Award performance period			3 years
1992 Plan | Restricted Stock Units (RSUs)
Class of Stock [Line Items]
Vesting period, in years	4 years
Vested in first period of employment	0
Award vesting period, quarters	12
2011 Equity Incentive Plan | Restricted Stock Units (RSUs)
Class of Stock [Line Items]
Vesting period, in years	4 years
Vested in first period of employment	0
Award vesting period, quarters	12
FY2015 Short Term Plan | Minimum
Class of Stock [Line Items]
Award pay out percentage				50.00%
FY2015 Short Term Plan | Maximum
Class of Stock [Line Items]
Award pay out percentage				150.00%

Stockholders_Equity_Employee_S

Stockholders' Equity - Employee Stock Purchase Plan (Details) (Employee Stock Purchase Plan [Member], 2012 Employee Stock Purchase Plan)	9 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Aug. 31, 2014	Aug. 30, 2012
Employee Stock Purchase Plan [Member] | 2012 Employee Stock Purchase Plan
Class of Stock [Line Items]
Common stock reserved for issuance				1.8
Additional shares reserved for issuance			2
Percentage of purchase price of common stock equal to fair market value	85.00%
Common stock, shares issued, employee stock purchase plan	0.2	0.3
Shares available for future issuance	2.3

StockBased_Compensation_StockB

Stock-Based Compensation Stock-Based Compensation (Details) (USD $)	9 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life (years)	6 months	6 months
Risk-free interest rate	0.10%	0.10%
Volatility	57.00%	57.00%
Dividend yield	0.00%	0.00%
Weighted average fair value	$2.57	$3.67
Equity Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life (years)		4 years 5 months
Risk-free interest rate		0.60%
Volatility		49.00%
Dividend yield		0.00%
Weighted average fair value		$2.95

StockBased_Compensation_Detail

Stock-Based Compensation (Details 2) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Summary of Stock-Based Compensation Expense of Stock Options and Restricted Stock Units
Stock-based compensation expense by type of grant	$4,882	$5,879	$14,308	$13,441
Stock-based compensation expensed from (capitalized to) inventory	25	-3	5	11
Total stock-based compensation expense	4,857	5,882	14,303	13,430
Cost of Revenues [Member]
Summary of Stock-Based Compensation Expense of Stock Options and Restricted Stock Units
Stock-based compensation expense by type of grant	97	118	226	353
Research and Development Expense [Member]
Summary of Stock-Based Compensation Expense of Stock Options and Restricted Stock Units
Stock-based compensation expense by type of grant	2,992	1,545	9,039	4,867
Selling General and Administrative [Member]
Summary of Stock-Based Compensation Expense of Stock Options and Restricted Stock Units
Stock-based compensation expense by type of grant	1,793	4,216	5,043	8,221
Stock Options [Member]
Summary of Stock-Based Compensation Expense of Stock Options and Restricted Stock Units
Stock-based compensation expense by type of grant	454	648	1,160	1,987
Restricted Stock Units [Member]
Summary of Stock-Based Compensation Expense of Stock Options and Restricted Stock Units
Stock-based compensation expense by type of grant	$4,428	$5,231	$13,148	$11,454

StockBased_Compensation_Detail1

Stock-Based Compensation (Details Textual) (USD $)	3 Months Ended			9 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Weighted average grant-date fair value per share of the restricted stock units awarded	$5.82		$9.84	$8.20	$8.57
Forfeiture rate		5.80%	6.70%
Unearned stock-based compensation	$29.80			$29.80
Weighted-average period over which the unearned stock-based compensation is expected to be recognized, years				2 years 3 months 0 days

Commitments_and_Contingencies_1

Commitments and Contingencies Commitments (Details) (USD $)	Dec. 31, 2014
Operating Leases
2015 (remainder of year)	$616,000	[1]
2016	1,528,000	[1]
2017	1,093,000	[1]
2018	632,000	[1]
Total minimum payments	3,869,000	[1]
Purchase Commitments
2015 (remainder of year)	16,909,000	[2]
2016	13,368,000	[2]
2017	3,241,000	[2]
2018	2,833,000	[2]
Total minimum payments	36,351,000	[2]
Total
2015 (remainder of year)	17,525,000
2016	14,896,000
2017	4,334,000
2018	3,465,000
Total minimum payments	40,220,000
Licensing Costs Due	$21,100,000
[1]	Includes the Company's headquarters building lease which expires in August 2015, subject to our right to terminate early upon at least 120 days’ notice.
[2]	Includes open purchase orders with terms that generally allow us the option to cancel or reschedule the order, subject to various restrictions and limitations. Also includes the licensing fees relating to the Company's R&D efforts, including licensed intellectual property, or IP, technology, product design, test and verification tools, of $21.1 million.

Contingencies_Details

Contingencies (Details)	1 Months Ended		9 Months Ended
	Jan. 31, 2012	Jan. 31, 2009	Dec. 31, 2014
		Amendments	Company
Contingencies (Textual) [Abstract]
Companies named as Potentially Responsible Parties (more than)			100
Amendments approved to consent decree		2
Percent of contribution to the total waste	0.50%

Sale_of_TPack_AS_Details

Sale of TPack A/S (Details) (TPack [Member], USD $)	0 Months Ended
In Millions, unless otherwise specified	Apr. 22, 2013
TPack [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sales price of subsidiary	$33.50

Subsequent_Events_Details

Subsequent Events (Details) (Subsequent Event [Member], Restructuring Plan [Member], USD $)	0 Months Ended
In Millions, unless otherwise specified	Jan. 23, 2015
	employee
Subsequent Event [Line Items]
Number of positions expected to be eliminated	40
Number of positions expected to be eliminated (percent)	7.00%
Minimum [Member]
Subsequent Event [Line Items]
Expected cost of restructuring plan	1.5
Reduction in operating expenses	14
Maximum [Member]
Subsequent Event [Line Items]
Expected cost of restructuring plan	1.7
Reduction in operating expenses	18