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

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-Publisher FASB

-Name Accounting Standards Codification

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-Name Staff Accounting Bulletin (SAB)

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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.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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).

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-Topic 820

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- Definition

Amount of capitalized and expensed compensation cost from equity-based compensation arrangements.

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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.

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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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- 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)

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section D

-Subsection 2

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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.

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

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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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- Definition

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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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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.

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Summary of Significant Accounting Policies - Stock-Based Compensation (Details) (USD $)	12 Months Ended			9 Months Ended	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013	Mar. 31, 2015
Share-based Compensation, Allocation and Classification
Stock-based compensation expense	$ 18,300,000	$ 17,037,000	$ 24,089,000
Stock-based compensation expensed from (capitalized to) inventory	5,000	(16,000)	147,000
Total stock-based compensation expense	18,305,000	17,021,000	24,236,000
Share-based Compensation Fair Value Assumptions Used
Expected dividend yield	0.00%
Cost of Revenues
Share-based Compensation, Allocation and Classification
Stock-based compensation expense	285,000	460,000	545,000
Research and Development Expense
Share-based Compensation, Allocation and Classification
Stock-based compensation expense	11,657,000	6,371,000	11,760,000
Selling General and Administrative
Share-based Compensation, Allocation and Classification
Stock-based compensation expense	6,358,000	10,206,000	11,784,000
Stock Options
Share-based Compensation, Allocation and Classification
Stock-based compensation expense	1,408,000	2,520,000	3,469,000
Share-based Compensation Fair Value Assumptions Used
Expected life (in years)		4 years 4 months 24 days	4 years 4 months 24 days
Risk-free interest rate (percentage)		0.60%	0.70%
Volatility (percentage)		49.00%	54.00%
Dividend yield (percentage)		0.00%	0.00%
Expected forfeiture rate (percentage)		5.80%	6.60%
Weighted average fair value (USD per share)		$ 2.95	$ 2.47
Employee Stock Purchase Plans
Share-based Compensation Fair Value Assumptions Used
Expected life (in years)	6 months	6 months	6 months
Risk-free interest rate (percentage)	0.10%	0.00%	0.00%
Volatility (percentage)	57.00%	56.00%	50.00%
Dividend yield (percentage)	0.00%	0.00%	0.00%
Expected forfeiture rate (percentage)	0.00%	0.00%	0.00%
Weighted average fair value (USD per share)	$ 2.17	$ 3.40	$ 1.77
Options and Restricted Stock Units \| Minimum
Share-based Compensation Fair Value Assumptions Used
Expected forfeiture rate (percentage)				5.80%
Options and Restricted Stock Units \| Maximum
Share-based Compensation Fair Value Assumptions Used
Expected forfeiture rate (percentage)					6.10%
Restricted Stock Units (RSUs)
Share-based Compensation, Allocation and Classification
Stock-based compensation expense	16,892,000	14,517,000	20,620,000
Share-based Compensation Fair Value Assumptions Used
Weighted average grant-date fair value per share of the restricted stock units awarded (USD per share)	$ 7.81	$ 9.46	$ 6.11
Unearned stock-based compensation	$ 24,600,000				24,600,000
Weighted-average period over which the unearned stock-based compensation is expected to be recognized, years	1 year 2 months 12 days