Equity-Based Compensation - Activity Related to Plans (Details) $ in Millions	1 Months Ended	3 Months Ended
Mar. 31, 2019 USD ($) shares	Mar. 31, 2019 USD ($) plan shares
Equity compensation plans
Number of equity compensation plans \| plan		3
Stock Options
Outstanding (in shares)		3,716,579
Granted (in shares)		401,583
Exercised (in shares)		(2,025)
Expired or terminated (in shares)		(227,744)
Outstanding (in shares)	3,888,393	3,888,393
Restricted Stock Units
Restricted Stock Units
Outstanding (in shares)		1,128,535
Granted (in shares)		1,010,919
Vested (in shares)		(320,546)
Expired or terminated (in shares)		(99,163)
Outstanding (in shares)	1,719,745	1,719,745
2007 Equity Plan
Stock Options
Outstanding (in shares)		2,781,786
Granted (in shares)		358,683
Exercised (in shares)		(2,025)
Expired or terminated (in shares)		(214,881)
Outstanding (in shares)	2,923,563	2,923,563
2007 Equity Plan \| Restricted Stock Units
Restricted Stock Units
Outstanding (in shares)		1,041,141
Granted (in shares)		1,007,719
Vested (in shares)		(309,877)
Expired or terminated (in shares)		(99,163)
Outstanding (in shares)	1,639,820	1,639,820
2007 Equity Plan \| Performance Restricted Stock Units (RSUs)
Restricted Stock Units
Granted (in shares)	365,591
Award vesting period		3 years
Maximum shares that may be issued (in shares)	365,591	365,591
Fair value, performance- based RSUs \| $	$ 4.7	$ 4.7
Compensation expense, period for recognition		3 years
2013 Lumara Equity Plan
Stock Options
Outstanding (in shares)		124,450
Granted (in shares)		26,400
Exercised (in shares)		0
Expired or terminated (in shares)		(10,613)
Outstanding (in shares)	140,237	140,237
2013 Lumara Equity Plan \| Restricted Stock Units
Restricted Stock Units
Outstanding (in shares)		2,101
Granted (in shares)		1,100
Vested (in shares)		0
Expired or terminated (in shares)		0
Outstanding (in shares)	3,201	3,201
Inducement Grants
Stock Options
Outstanding (in shares)		810,343
Granted (in shares)		16,500
Exercised (in shares)		0
Expired or terminated (in shares)		(2,250)
Outstanding (in shares)	824,593	824,593
Inducement Grants \| Restricted Stock Units
Restricted Stock Units
Outstanding (in shares)		85,293
Granted (in shares)		2,100
Vested (in shares)		(10,669)
Expired or terminated (in shares)		0
Outstanding (in shares)	76,724	76,724

Share-Based Compensation Arrangements By Share-Based Payment Award, Number Of Plans

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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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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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

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