Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Forfeiture Rate.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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- Definition

Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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-Publisher FASB

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Expected dividends to be paid to holders of the underlying shares or financial instruments (expressed as a percentage of the share or instrument's price).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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-Name Accounting Standards Codification

-Topic 230

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(2)

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.D.2)

-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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-Section 50

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-Subparagraph (f)(2)(i)

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section D

-Subsection 2

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (f)(2)(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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Summary of Significant Accounting Policies - Stock-Based Compensation (Details) (USD $)	12 Months Ended												9 Months Ended	12 Months Ended									3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2014 Cost of Revenues	Mar. 31, 2013 Cost of Revenues	Mar. 31, 2012 Cost of Revenues	Mar. 31, 2014 Research and Development Expense	Mar. 31, 2013 Research and Development Expense	Mar. 31, 2012 Research and Development Expense	Mar. 31, 2014 Selling General and Administrative	Mar. 31, 2013 Selling General and Administrative	Mar. 31, 2012 Selling General and Administrative	Dec. 31, 2013 Stock Options	Mar. 31, 2014 Stock Options	Mar. 31, 2013 Stock Options	Mar. 31, 2012 Stock Options	Mar. 31, 2014 Restricted Stock Units (RSUs)	Mar. 31, 2013 Restricted Stock Units (RSUs)	Mar. 31, 2012 Restricted Stock Units (RSUs)	Mar. 31, 2014 Employee Stock Purchase Plans	Mar. 31, 2013 Employee Stock Purchase Plans	Mar. 31, 2012 Employee Stock Purchase Plans	Jun. 30, 2013 Veloce Warrants
Share-based Compensation, Allocation and Classification
Share-based Compensation	$ 17,037,000	$ 24,089,000	$ 18,437,000	$ 460,000	$ 545,000	$ 495,000	$ 6,371,000	$ 11,760,000	$ 10,496,000	$ 10,206,000	$ 11,784,000	$ 7,446,000		$ 2,520,000	$ 3,469,000	$ 5,289,000	$ 14,517,000	$ 20,620,000	$ 13,148,000
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount	(16,000)	147,000	(63,000)
Allocated Share-based Compensation Expense	17,021,000	24,236,000	18,374,000																				1,300,000
Share-based Compensation Fair Value Assumptions Used
Expected life (in years)														4 years 4 months 24 days	4 years 4 months 24 days	3 years 9 months 18 days				6 months	6 months	6 months
Risk-free interest rate (percentage)														0.60%	0.70%	1.40%				0.00%	0.00%	0.10%
Volatility (percentage)														49.00%	54.00%	48.00%				56.00%	50.00%	55.00%
Dividend yield (percentage)														0.00%	0.00%	0.00%				0.00%	0.00%	0.00%
Expected forfeiture rate (percentage)													6.60%	5.80%	6.60%	6.80%				0.00%	0.00%	0.00%
Weighted average fair value (USD per share)														$ 2.95	$ 2.47	$ 3.83				$ 3.40	$ 1.77	$ 2.13
Expected dividend yield	0.00%
Weighted average grant-date fair value per share of the restricted stock units awarded (USD per share)																	$ 9.46	$ 6.11	$ 9.00
Unearned stock-based compensation	$ 24,100,000
Weighted-average period over which the unearned stock-based compensation is expected to be recognized, years	1 year 6 months 12 days