Equity-Based Compensation - Activity Related to Plans (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
Feb. 28, 2017	Dec. 31, 2017
Stock Options
Beginning balance (shares)		3,113,178
Granted (shares)		1,145,992
Exercised (shares)		(92,529)
Expired or forfeited (shares)		(635,282)
Ending balance (shares)		3,531,359
2007 Equity Plan
Stock Options
Beginning balance (shares)		2,158,822
Granted (shares)		1,044,817
Exercised (shares)		(92,529)
Expired or forfeited (shares)		(520,737)
Ending balance (shares)		2,590,373
2000 Equity Plan
Stock Options
Beginning balance (shares)		5,200
Granted (shares)		0
Exercised (shares)		0
Expired or forfeited (shares)		(5,200)
Ending balance (shares)		0
Restricted Stock Units
Remaining number of shares available for future grants (shares)		0
2013 Lumara Equity Plan
Stock Options
Beginning balance (shares)		134,181
Granted (shares)		10,075
Exercised (shares)		0
Expired or forfeited (shares)		(18,720)
Ending balance (shares)		125,536
Inducement Grants
Stock Options
Beginning balance (shares)		814,975
Granted (shares)		91,100
Exercised (shares)		0
Expired or forfeited (shares)		(90,625)
Ending balance (shares)		815,450
RSUs
Restricted Stock Units
Outstanding at beginning of year (shares)		936,954
Granted (shares)		821,327
Vested (shares)		(431,190)
Forfeited (shares)		(257,316)
Outstanding at end of year (shares)		1,069,775
Compensation expense, period for recognition		1 year 8 months 18 days
RSUs \| 2007 Equity Plan
Restricted Stock Units
Outstanding at beginning of year (shares)		773,804
Granted (shares)		797,027
Vested (shares)		(361,548)
Forfeited (shares)		(242,660)
Outstanding at end of year (shares)		966,623
RSUs \| 2000 Equity Plan
Restricted Stock Units
Outstanding at beginning of year (shares)		0
Granted (shares)		0
Vested (shares)		0
Forfeited (shares)		0
Outstanding at end of year (shares)		0
RSUs \| 2013 Lumara Equity Plan
Restricted Stock Units
Outstanding at beginning of year (shares)		27,694
Granted (shares)		0
Vested (shares)		(13,330)
Forfeited (shares)		(2,753)
Outstanding at end of year (shares)		11,611
RSUs \| Inducement Grants
Restricted Stock Units
Outstanding at beginning of year (shares)		135,456
Granted (shares)		24,300
Vested (shares)		(56,312)
Forfeited (shares)		(11,903)
Outstanding at end of year (shares)		91,541
Award vesting period		3 years
Performance Restricted Stock Units (RSUs)
Restricted Stock Units
Compensation expense, period for recognition		2 years 1 month
Performance Restricted Stock Units (RSUs) \| 2007 Equity Plan
Restricted Stock Units
Granted (shares)	191,250
Award vesting period	3 years
Remaining number of shares available for future grants (shares)		162,750
Fair value, performance- based RSUs		$ 3.2
Compensation expense, period for recognition		3 years

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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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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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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