Stockholders' Equity (Details Textual) (USD $)	1 Months Ended		9 Months Ended				9 Months Ended						9 Months Ended	1 Months Ended		9 Months Ended		1 Months Ended	9 Months Ended						1 Months Ended		9 Months Ended	1 Months Ended									1 Months Ended								1 Months Ended
	Oct. 31, 2008	Aug. 31, 2004	Dec. 31, 2012 Approved_Plan	Dec. 31, 2011	Mar. 31, 2012	May 15, 2006	Dec. 31, 2012 Minimum [Member]	Dec. 31, 2012 Maximum [Member]	Dec. 31, 2012 Employee Stock Purchase Plan [Member]	Dec. 31, 2011 Employee Stock Purchase Plan [Member]	Aug. 30, 2012 Employee Stock Purchase Plan [Member]	Aug. 30, 2010 Employee Stock Purchase Plan [Member]	Dec. 31, 2012 Employee Stock Purchase Plan [Member] All Previous Stock Plans [Member]	Aug. 31, 2012 Employee Stock Purchase Plan [Member] Two Thousand Twelve Plan [Member]	Aug. 31, 2004 Stock Repurchase Program - Open Market [Member]	Dec. 31, 2012 Stock Repurchase Program - Open Market [Member]	Dec. 31, 2011 Stock Repurchase Program - Open Market [Member]	Aug. 31, 2004 Structured stock repurchase agreements [Member]	Dec. 31, 2012 Structured stock repurchase agreements [Member]		Dec. 31, 2011 Structured stock repurchase agreements [Member]	Dec. 31, 2012 Settlement of Structured Stock Repurchase Agreement [Member]	Apr. 30, 2011 Company's 2011 Equity Incentive Plan [Member] Minimum [Member]	Dec. 31, 2012 Company's 2011 Equity Incentive Plan [Member] Maximum [Member]	Feb. 29, 2012 Restricted Stock Units [Member]	May 31, 2006 Restricted Stock Units [Member] quarter	Dec. 31, 2012 Restricted Stock Units [Member]	Nov. 30, 2011 Restricted Stock Units [Member] Minimum [Member]	Nov. 30, 2011 Restricted Stock Units [Member] Maximum [Member]	May 31, 2009 First Milestone - From Fiscal 2010 To 2013 [Member]	May 31, 2009 Second Milestone - From Fiscal 2010 To 2013 [Member]	May 31, 2009 Second Milestone - Fiscal 2014 [Member]	May 31, 2009 Third Milestone - Fiscal 2013 [Member]	May 31, 2009 Third Milestone - Fiscal 2010 To 2012 [Member]	Dec. 31, 2012 Common Stock Subject to Repurchase [Member]	Mar. 31, 2012 Common Stock Subject to Repurchase [Member]	May 31, 2012 Performance-Based RSU [Member]	Feb. 29, 2012 Performance-Based RSU [Member]	Nov. 30, 2011 Performance-Based RSU [Member]	Apr. 30, 2011 Performance-Based RSU [Member]	May 31, 2009 Performance-Based RSU [Member]	Feb. 29, 2012 Chief Executive Officer [Member]	May 31, 2009 Chief Executive Officer [Member]	May 17, 2009 Veloce Technologies, Inc. [Member]	May 31, 2012 First Vesting Period [Member]	May 31, 2012 Second Vesting Period [Member]
Stockholders Equity [Line Items]
Preferred stock, shares authorized for issuance			2,000,000		2,000,000
Common stock, shares authorized for issuance			375,000,000		375,000,000
Common stock, shares issued			67,032,000		61,879,000
Common stock, shares outstanding			67,032,000		61,879,000
Common stock reserved for issuance									4,800,000			6,300,000
Shares available for future issuance											1,800,000												4,200,000	10,900,000
Percentage of purchase price of common stock equal to fair market value									85.00%
Common stock, shares issued, employee stock purchase plan									400,000	400,000			6,600,000	1,800,000
Stock repurchase program, authorized amount		$ 200,000,000	$ 300,000,000
Increase in the amount authorized for stock purchase program	100,000,000
Open market repurchased shares			100,000
Open Market Repurchased Shares Average Cost Per Share			$ 5.18
Stock repurchase program, shares repurchased			27,273,000												17,300,000	100,000	3,500,000		9,989,000	[1]
Stock repurchase program, weighted average price per share		$ 10.04	$ 0													$ 5.18	$ 5.98		$ 0	[1]
Structured stock repurchase agreement, amount																		277,500,000			10,000,000
Structured stock repurchase agreement, shares received																					1,000,000	10,000,000
Structured stock repurchase agreements, effective purchase price per share																					$ 9.74	$ 9.78
Cash received from shares settled under structured stock agreements																						179,800,000
Gain recorded to additional paid-in-capital																			12,800,000
Adjusted average price per share for repurchases																			$ 9.78
Total repurchases, price per share, adjusted from gains settlements in cash			$ 9.97
Number of stockholder-approved plans			2
Number of plans unapproved by stockholders			4
Options expiration period, in years			10 years
Vesting period, in years																										4 years	4 years	1 year	18 months								1 year
Vesting and exercisable rate of new hire grants, percentage			25.00%
Vesting and exercisable rate of new hire grants, grant date							36 months	48 months
Awards granted			40,000																						500,000																		300,000
Value of stock options awarded																																										3,700,000	1,100,000
Shares expected to vest			3,105,000																											75,000	75,000		150,000
Annual target revenue																														270,000,000	310,000,000	350,000,000
Percentage of annual operating margin required for vesting of shares under milestone																																	13.50%	15.00%
Shares outstanding			3,688,000		4,164,000																														0	0
Weighted average remaining contractual term for options outstanding			3 years 3 months 18 days
Weighted average remaining contractual term for options vested			3 years 3 months 18 days
Aggregate pretax intrinsic value of options exercised			100,000
Pre-tax intrinsic value of options outstanding			2,200,000
Pre-tax intrinsic value of options exercisable			1,800,000
Common stock, closing price per share			$ 8.42																								$ 8.42
Number of shares vested			6,664,000		9,244,000	0
Award vesting period, quarters																										12
Term of award																																					P12M	P18M	18-month	P3Y	P3Y
Award vesting percentage																																													66.67%	33.33%
Weighted average remaining contractual term for the restricted stock units outstanding, in years			1 year 4 months 28 days
Aggregate pre-tax intrinsic value of restricted stock units outstanding which includes performance based awards which are subject to milestone attainments			56,100,000
Share Based Compensation Arrangement by Share Based Payment Award Equity Other than Options Aggregate Pre Tax Intrinsic Value Released			13,000,000
Number of years of development work to be performed																																												5 years
Stock-based compensation expense related to the acceleration of Veloce warrants			$ 1,289,000	$ 0

[1] The amounts above do not include gains recorded to additional paid-in-capital of $12.8 million from structured stock repurchase agreements which settled in cash. The average price per share for structured stock repurchase agreements adjusted for gains from settlements in cash would have been $9.78 per share and for total repurchases would have been $9.97 per share.