Discount rate from fair value on offering date that participants pay for shares.

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Number of additional shares authorized for issuance under an established share-based compensation plan.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Gross number of share options (or share units) granted during the period.

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No definition available.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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As of the balance sheet date, the weighted-average exercise price (at which grantees can acquire the shares reserved for issuance) for exercisable stock options that are fully vested or expected to vest.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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No definition available.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options that are exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Purchase price of common stock expressed as a percentage of its fair value.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Number of share options (or share units) exercised during the current period.

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Stock Option Plans - Plan Information (Details) - $ / shares	1 Months Ended				9 Months Ended	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2016	Dec. 31, 2015	Aug. 31, 2015	Dec. 31, 2008
Number of Shares
Outstanding at beginning of period (in shares)					1,529,459
Granted (in shares)					928,250
Exercised (in shares)					(5,313)
Forfeited/canceled (in shares)					(350,432)
Outstanding at end of period (in shares)					2,101,964	1,529,459
Exercisable at end of period (in shares)					646,142
Weighted Average Exercise Price
Outstanding at beginning of period (in USD per share)					$ 6.29
Granted (in USD per share)					4.41
Exercised (in USD per share)					1.65
Forfeited/canceled (in USD per share)					6.85
Outstanding at end of period (in USD per share)					5.37	$ 6.29
Exercisable at end of period (in USD per share)					$ 5.33
Additional disclosures
Weighted Average Remaining Contractual Life (years)					8 years 7 months 24 days	9 years
Weighted Average Remaining Contractual Life (years), Options exercisable					7 years 4 months 24 days
ESPP
Stock Option Plans
Number of stock options and stock purchase rights available for grant (in shares)					375,485
Percentage of discount for employees under ESPP					15.00%
Purchase price as a percentage of fair value under ESPP					85.00%
Shares issued during the period under ESPP (in shares)					0
2008 Plan
Stock Option Plans
Number of stock options and stock purchase rights available for grant (in shares)		1,061,585	669,935	554,782				330,582
Expiration period					10 years
Increase in number of stock options and stock purchase rights available for grant (in shares)		391,650	115,153	224,200
Number of Shares
Outstanding at end of period (in shares)					764,928
2015 Plan
Stock Option Plans
Number of stock options and stock purchase rights available for grant (in shares)							1,671,800
Increase in number of stock options and stock purchase rights available for grant (in shares)	1,041,527
2008 Plan and 2015 Plan
Stock Option Plans
Number of stock options and stock purchase rights available for grant (in shares)					3,508,492