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The cash outflow for cost incurred directly with the issuance of an equity security.

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Number of additional shares authorized for issuance under share-based payment arrangement.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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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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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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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 price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Price of a single share of a number of saleable stocks of a company.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Number of new stock issued during the period.

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Stockholders' Equity - Additional Information (Details) - USD ($)	1 Months Ended													12 Months Ended
	Oct. 31, 2019	Jun. 30, 2019	Jun. 30, 2018	Apr. 30, 2018	Jun. 30, 2017	Jun. 30, 2016	May 31, 2015	Jun. 30, 2014	May 31, 2014	Jun. 30, 2011	May 31, 2010	May 31, 2009	Dec. 31, 2007	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 1997
Class Of Stock [Line Items]
Proceeds from issuance of common stock	$ 162,200,000		$ 194,400,000	$ 168,700,000											$ 162,151,000	$ 363,128,000
Class of warrant or right, number of securities called by warrants or rights														220,164
Common stock, shares, issued, total														91,310,000	90,304,000
Common stock, capital shares reserved for future issuance														30,997,847
Share-based compensation arrangement by share-based payment award, number of shares available for grant														1,575,955
Share-based compensation arrangement by share-based payment award, expiration period														10 years
Share-based compensation arrangement by share-based payment award, award vesting period														4 years
Share-based compensation arrangement by share-based payment award, options, exercisable, weighted average remaining contractual term														5 years 8 months 12 days
Share-based compensation arrangement by share-based payment award, options, exercises in period, intrinsic value														$ 3,200	$ 25,000.0
Share-based compensation arrangement by share-based payment award, options, outstanding, intrinsic value														$ 69,100	$ 56,300
Common stock future issuance on exercise of outstanding options and vesting of outstanding restricted stock units granted														19,515,270
Total unrecognized compensation cost related to non-vested, stock-based payment awards														$ 116,100,000
Total unrecognized compensation cost, expect to recognize over weighted average period														2 years 9 months 18 days
Stock Option and RSUs
Class Of Stock [Line Items]
Share-based compensation arrangements by share-based payment award, options, exercises in period, weighted average exercise price														$ 12.41	$ 11.18	$ 11.97
Share-based compensation arrangement by share-based payment award, options, forfeitures in period														922,578
Share-based compensation arrangements by share-based payment award, options, forfeitures in period, weighted average exercise price														$ 22.76
Share-based Payment Arrangement, Option
Class Of Stock [Line Items]
Share-based compensation arrangement by share-based payment award, options, expirations in period														342,293
Share-based compensation arrangements by share-based payment award, options, expirations in period, weighted average exercise price														$ 23.04
Expected life														6 years	6 years	6 years
Restricted Stock Units
Class Of Stock [Line Items]
Share-based compensation arrangement by share-based payment award, award vesting period														4 years
Employee Stock Purchase Plan
Class Of Stock [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized																		10,000
Share-based compensation arrangement by share-based payment award, number of additional shares authorized		300,000			200,000	100,000	100,000		25,000	25,000		10,000	5,000	775,000
Share-based compensation arrangement by share-based payment award maximum employee earnings with held to purchase common stock percent														10.00%
Share-based compensation arrangement by share-based payment award discount on stock price														85.00%
Share-based compensation arrangement by share-based payment award, shares issued in period														193,841	125,727	71,499
Share-based compensation arrangements by share-based payment award, options, exercises in period, weighted average exercise price														$ 11.95	$ 16.77	$ 16.48
Common stock, shares, issued, total														598,750
Common stock, capital shares reserved for future issuance														176,250
Share-based compensation arrangement by share-based payment award, options, grants in period, weighted average grant date fair value														$ 9.76	14.70	17.24
Share-based compensation arrangement by share-based payment award, per share weighted-average fair value price of shares purchased														$ 5.18	$ 5.94	$ 9.95
Expected life														6 months
Equity Incentive Plan 2007
Class Of Stock [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized													150,000
Share-based compensation arrangement by share-based payment award, number of additional shares authorized		7,000,000			5,000,000	3,000,000	4,300,000		1,750,000	4,500,000	100,000			25,800,000
Share-based compensation arrangement by share-based payment award, number of shares available for grant														1,575,955
Pre-funded Warrants
Class Of Stock [Line Items]
Class of warrant or right, number of securities called by warrants or rights								600,000
Class of warrant or right, exercise price of warrants or rights								$ 0.01
Class of warrant or right, expiration date								Jun. 30, 2021
Class of warrant or right, exercised during period														267,870	132,130		4,426
Proceeds from issuance of warrants														$ 2,679,000	$ 1,321,000		$ 0
Class of warrant or right, outstanding														195,574
Common Stock
Class Of Stock [Line Items]
Number of shares issued	9,900,000		5,100,000	6,900,000											9,857,000	11,963,000
Share price	$ 17.50		$ 39.50	$ 26.00
Payments of stock issuance costs	$ 10,300,000		$ 5,600,000	$ 10,700,000
Issuance of common stock on exercise of warrants (in shares)														267,000	132,000
Common Stock \| Pre-funded Warrants
Class Of Stock [Line Items]
Issuance of common stock on exercise of warrants (in shares)														267,870	132,130		4,423