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Computation Of Net (Loss) Income Per Common Share (Details) (USD $) In Thousands, except Share data	3 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Computation Of Net (Loss) Income Per Common Share
Net (loss) income	$ (37,679)	$ 9,170
Weighted-average shares of common stock outstanding	51,172,000	45,454,000
Weighted-average shares subject to repurchase	(463,000)	(212,000)
Shares used in per-share calculation - basic	50,709,000	45,242,000
Dilutive effect of employee equity incentive plans		741,000
Shares used in per-share calculation - diluted	50,709,000	45,983,000
Net (loss) income per share basic	$ (0.74)	$ 0.20
Net (loss) income per share diluted	$ (0.74)	$ 0.20
Common equivalent shares excluded from calculation of diluted EPS as they were considered anti-dilutive	3.0	1.4

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Computation of Net Income per Common Share [Abstract]

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Dilutive Effect Of Employee Equity Incentive Plans Shares

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Weighted Average Shares Of Common Stock Outstanding

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) in the future that were not included in the computation of diluted EPS because to do so would increase EPS amounts or decrease loss per share amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 13, 14

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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The amount of net income or loss for the period per each share of common stock outstanding during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 21
-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 36, 37, 38

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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
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-Article 5

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The amount of net income or loss for the period per each share of common stock and dilutive common stock equivalents outstanding during the reporting period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 11, 12, 36

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-Publisher SEC
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The portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 19
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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-Number 210
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-Paragraph 20
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 87-21

Reference 8: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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The average number of shares issued and outstanding that are used in calculating diluted EPS, determined based on the timing of issuance of shares in the period.

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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Number of shares of common stock subject to repurchase or cancellation determined by relating the portion of time within a reporting period that these shares have been outstanding to the total time in that period. Common stock subject to repurchase are outstanding common shares that are contingently returnable (that is, subject to recall).

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Number of [basic] shares, after adjustment for contingently issuable shares and other shares not deemed outstanding, determined by relating the portion of time within a reporting period that common shares have been outstanding to the total time in that period.

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