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Unrecognized cost of unvested share-based compensation awards.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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

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

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

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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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Summary of Significant Accounting Policies - Stock-Based Compensation (Details)		1 Months Ended			3 Months Ended		9 Months Ended	12 Months Ended
	Jul. 01, 2017 shares	Jun. 30, 2017 item $ / shares shares	Feb. 28, 2017 item $ / shares shares	Aug. 31, 2016 item $ / shares shares	Mar. 31, 2019 USD ($) item $ / shares shares	Mar. 31, 2018 USD ($) $ / shares	Sep. 30, 2018 USD ($)	Dec. 31, 2018 $ / shares shares	Jun. 30, 2018 shares
Stock plans disclosure
Cash received for exercise of stock options \| $					$ 68,000	$ 2,259,000
ESPP
Weighted-average assumptions used to estimate the fair value of each stock option
Dividend (as a percent)					0.00%
Volatility (as a percent)					67.30%
Risk-free interest rate (as a percent)					2.51%
Expected life					6 months
Weighted-Average Grant Date Fair Value
Awarded (in dollars per share) \| $ / shares					$ 1.63
Stock plans disclosure
Aggregate number of common shares reserved for future issuance									1,000,000
Estimated subscriptions outstanding					242,000
Stock compensation expense \| $					$ 197,000
Stock options and restricted stock awards
Stock plans disclosure
Stock compensation expense \| $					5,000,000		$ 3,700,000
Estimated fair value that could be expensed \| $					$ 38,800,000
Stock options
Weighted-average assumptions used to estimate the fair value of each stock option
Dividend (as a percent)					0.00%	0.00%
Volatility (as a percent)					73.57%	70.82%
Risk-free interest rate (as a percent)					2.47%	2.70%
Expected life					6 years	6 years
Weighted-average grant date fair value (in dollars per share) \| $ / shares					$ 3.46	$ 10.55
Number of Stock Options
Outstanding at the beginning of the period (in shares)					15,564,000
Granted (in shares)					4,840,000
Exercised (in shares)					(25,000)
Forfeited/Canceled (in shares)					(195,000)
Outstanding at the end of the period (in shares)					20,184,000			15,564,000
Weighted-Average Exercise Price
Outstanding at the beginning of the period (in dollars per share) \| $ / shares					$ 10.20
Granted (in dollars per share) \| $ / shares					5.25
Exercised (in dollars per share) \| $ / shares					2.73
Forfeited/Canceled (in dollars per share) \| $ / shares					9.68
Outstanding at the end of the period (in dollars per share) \| $ / shares					$ 9.03			$ 10.20
Stock plans disclosure
Cash received for exercise of stock options \| $					$ 68,000
Stock options \| Minimum
Weighted-Average Exercise Price
Exercised (in dollars per share) \| $ / shares					$ 2.03
Stock options \| Maximum
Weighted-Average Exercise Price
Exercised (in dollars per share) \| $ / shares					$ 3.05
Performance shares
Stock-Based Compensation
Exercise period								5 years
Number of equal installments restrictions lapse								2
Number of Restricted Stock Shares
Awarded (in shares)								295,200
Stock plans disclosure
Stock compensation expense \| $					$ 0
Estimated fair value that could be expensed \| $					$ 1,700,000
Restricted stock
Stock-Based Compensation
Number of equal installments restrictions lapse \| item		3	3	3
Number of Restricted Stock Shares
Unvested at the beginning of the period (in shares)					1,816,000
Awarded (in shares)					13,000
Vested (in shares)					(485,000)
Forfeited (in shares)	(71,380)
Unvested at the end of the period (in shares)					1,344,000			1,816,000
Weighted-Average Grant Date Fair Value
Unvested at the beginning of the period (in dollars per share) \| $ / shares					$ 2.87
Vested (in dollars per share) \| $ / shares					2.52
Unvested at the end of the period (in dollars per share) \| $ / shares					$ 2.99			$ 2.87
Restricted stock \| Officers
Number of Restricted Stock Shares
Awarded (in shares)		239,000	529,830	117,800
Weighted-Average Grant Date Fair Value
Awarded (in dollars per share) \| $ / shares		$ 4.71	$ 2.47	$ 3.15
Stock plans disclosure
Stock compensation expense \| $					$ 0
Estimated fair value that could be expensed \| $					$ 2,600,000
2016 Plan \| Stock options
Weighted-average assumptions used to estimate the fair value of each stock option
Number of group of awards for which expected term is calculated for and applied \| item					1
2016 Plan \| Stock options \| Maximum
Stock-Based Compensation
Vesting period					4 years
Exercise period					10 years
2018 Plan
Stock-Based Compensation
Common stock authorized for issuance (in shares)					7,500,000
Previous stock option plans
Stock-Based Compensation
Common stock authorized for issuance (in shares)					19,500,000