v2.4.1.9

Net Income Per Share , Calculation of Basic and Diluted (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share [Line Items]
Net income	$ 1,560us-gaap_NetIncomeLoss	$ 8,393us-gaap_NetIncomeLoss
Basic shares:
Weighted-average common shares outstanding-basic (in shares)	168,077us-gaap_WeightedAverageNumberOfSharesOutstandingBasic	162,391us-gaap_WeightedAverageNumberOfSharesOutstandingBasic
Diluted shares:
Weighted-average common shares outstanding-basic (in shares)	168,077us-gaap_WeightedAverageNumberOfSharesOutstandingBasic	162,391us-gaap_WeightedAverageNumberOfSharesOutstandingBasic
Effect of potentially dilutive securities:
Weighted-average shares used to compute diluted net income per share (in shares)	173,720us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding	168,114us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding
Basic (in dollars per share)	$ 0.01us-gaap_EarningsPerShareBasic	$ 0.05us-gaap_EarningsPerShareBasic
Diluted (in dollars per share)	$ 0.01us-gaap_EarningsPerShareDiluted	$ 0.05us-gaap_EarningsPerShareDiluted
Stock options [Member]
Effect of potentially dilutive securities:
Employee stock options and purchase rights (in shares)	3,837us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements / us-gaap_AwardTypeAxis = us-gaap_EmployeeStockOptionMember	5,196us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements / us-gaap_AwardTypeAxis = us-gaap_EmployeeStockOptionMember
RSUs (including PSUs) [Member]
Effect of potentially dilutive securities:
Employee stock options and purchase rights (in shares)	1,741us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember	484us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements / us-gaap_AwardTypeAxis = us-gaap_RestrictedStockUnitsRSUMember
ESPP [Member]
Effect of potentially dilutive securities:
Employee stock options and purchase rights (in shares)	65us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements / us-gaap_AwardTypeAxis = us-gaap_EmployeeStockMember	43us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements / us-gaap_AwardTypeAxis = us-gaap_EmployeeStockMember

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