Equity-Based Compensation - Activity Related to Plans (Details)	12 Months Ended
Dec. 31, 2016 shares
Stock Options
Stock Options
Beginning balance (shares)	2,904,177
Granted (shares)	784,048
Exercised (shares)	(155,705)
Expired or forfeited (shares)	(419,342)
Ending balance (shares)	3,113,178
Stock Options \| 2007 Equity Plan
Stock Options
Beginning balance (shares)	1,963,162
Granted (shares)	581,648
Exercised (shares)	(134,455)
Expired or forfeited (shares)	(251,533)
Ending balance (shares)	2,158,822
Stock Options \| 2000 Equity Plan
Stock Options
Beginning balance (shares)	14,040
Granted (shares)	0
Exercised (shares)	0
Expired or forfeited (shares)	(8,840)
Ending balance (shares)	5,200
Stock Options \| 2013 Lumara Equity Plan
Stock Options
Beginning balance (shares)	96,000
Granted (shares)	92,400
Exercised (shares)	0
Expired or forfeited (shares)	(54,219)
Ending balance (shares)	134,181
Stock Options \| Inducement Grants
Stock Options
Beginning balance (shares)	830,975
Granted (shares)	110,000
Exercised (shares)	(21,250)
Expired or forfeited (shares)	(104,750)
Ending balance (shares)	814,975
RSUs
Restricted Stock Units
Outstanding at beginning of year (shares)	654,355
Granted (shares)	725,618
Vested (shares)	(300,567)
Forfeited (shares)	(142,452)
Outstanding at end of year (shares)	936,954
RSUs \| 2007 Equity Plan
Restricted Stock Units
Outstanding at beginning of year (shares)	446,330
Granted (shares)	659,618
Vested (shares)	(209,599)
Forfeited (shares)	(122,545)
Outstanding at end of year (shares)	773,804
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)	52,350
Granted (shares)	1,500
Vested (shares)	(16,749)
Forfeited (shares)	(9,407)
Outstanding at end of year (shares)	27,694
RSUs \| Inducement Grants
Restricted Stock Units
Outstanding at beginning of year (shares)	155,675
Granted (shares)	64,500
Vested (shares)	(74,219)
Forfeited (shares)	(10,500)
Outstanding at end of year (shares)	135,456

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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).

+ References

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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.

+ References

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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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

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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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