Stockholders' Equity - Employee Stock Purchase Plan (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance	10,325
2012 Employee Stock Purchase Plan \| Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance	3,800
Percentage of base salary that may be contributed to ESPP	20.00%
Percentage of purchase price of common stock equal to fair market value	85.00%
Shares available for future issuance	1,200
Number of shares purchased	600	700	700
Average purchase price of shares purchased (USD per share)	$ 4.62	$ 5.34	$ 7.93
Intrinsic value of shares purchased	$ 0.7	$ 0.6

Employee Stock Purchase Plan (ESPP), Average Purchase Price of Shares Purchased

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- Definition

Employee Stock Purchase Plan (ESPP), Contribution to ESPP, Percentage of Base Salary

+ References

No definition available.

+ Details

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- Definition

Employee Stock Purchase Plan (ESPP), Intrinsic Value of Shares Purchased

+ References

No definition available.

+ Details

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- Definition

Employee Stock Purchase Plan (ESPP), Shares Purchased

+ References

No definition available.

+ Details

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- Definition

Percentage of purchase price of common stock equal to fair market value.

+ References

No definition available.

+ Details

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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