Equity Incentive Plans (Stock Option Activity) (Details) - $ / shares	1 Months Ended	9 Months Ended
Mar. 31, 2019	Sep. 30, 2019
Shares Underlying Stock Options
Outstanding beginning balance, Shares underlying stock options and restricted stock awards (in shares)		6,466,214
Granted, Shares underlying stock options and restricted stock awards (in shares)		1,982,402
Forfeited, Shares underlying stock options and restricted stock awards (in shares)		(1,503,029)
Outstanding ending balance, Shares underlying stock options and restricted stock awards (in shares)		6,945,587
Weighted- Average Exercise Price per Share
Outstanding beginning balance, Weighted - average exercise price (usd per share)		$ 23.26
Granted, Weighted - average exercise price (usd per share)		6.43
Forfeited, Weighted - average exercise price (usd per share)		20.62
Outstanding ending balance, Weighted - average exercise price (usd per share)		$ 19.03
Chief Commercial Officer [Member]
Shares Underlying Stock Options
Granted, Shares underlying stock options and restricted stock awards (in shares)	80,000
Employee Stock Option [Member] \| Chief Commercial Officer [Member]
Weighted- Average Exercise Price per Share
Options vesting percentage	25.00%
Award vesting period	3 years

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=109197908&loc=d3e5070-113901

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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 grantees can acquire the shares reserved for issuance under the stock option plan.

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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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Percentage of vesting of share-based compensation awards.

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