Equity-Based Compensation - Activity Related to Plans (Details) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($) plan shares
Equity compensation plans
Number of equity compensation plans \| plan	3
Stock Options
Outstanding (in shares)	3,531,359
Granted (in shares)	451,411
Exercised (in shares)	(7,782)
Expired or terminated (in shares)	(204,108)
Outstanding (in shares)	3,770,880
Restricted Stock Units
Restricted Stock Units
Outstanding (in shares)	1,069,775
Granted (in shares)	712,781
Vested (in shares)	(343,454)
Expired or terminated (in shares)	(38,538)
Outstanding (in shares)	1,400,564
2007 Equity Plan
Stock Options
Outstanding (in shares)	2,590,373
Granted (in shares)	451,411
Exercised (in shares)	(7,782)
Expired or terminated (in shares)	(160,797)
Outstanding (in shares)	2,873,205
2007 Equity Plan \| Restricted Stock Units
Restricted Stock Units
Outstanding (in shares)	966,623
Granted (in shares)	712,781
Vested (in shares)	(317,638)
Expired or terminated (in shares)	(38,078)
Outstanding (in shares)	1,323,688
2007 Equity Plan \| Performance Restricted Stock Units (RSUs)
Restricted Stock Units
Granted (in shares)	206,250
Award vesting period	3 years
Fair value, performance- based RSUs \| $	$ 3.8
Compensation expense, period for recognition	3 years
2013 Lumara Equity Plan
Stock Options
Outstanding (in shares)	125,536
Granted (in shares)	0
Exercised (in shares)	0
Expired or terminated (in shares)	(15,436)
Outstanding (in shares)	110,100
2013 Lumara Equity Plan \| Restricted Stock Units
Restricted Stock Units
Outstanding (in shares)	11,611
Granted (in shares)	0
Vested (in shares)	(10,150)
Expired or terminated (in shares)	(460)
Outstanding (in shares)	1,001
Inducement Grants
Stock Options
Outstanding (in shares)	815,450
Granted (in shares)	0
Exercised (in shares)	0
Expired or terminated (in shares)	(27,875)
Outstanding (in shares)	787,575
Inducement Grants \| Restricted Stock Units
Restricted Stock Units
Outstanding (in shares)	91,541
Granted (in shares)	0
Vested (in shares)	(15,666)
Expired or terminated (in shares)	0
Outstanding (in shares)	75,875

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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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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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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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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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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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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