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 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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Equity-Based Compensation - Activity Related to Plans (Details) - USD ($) $ in Millions	1 Months Ended		12 Months Ended
	Mar. 31, 2018	Feb. 28, 2017	Dec. 31, 2018
Stock Options
Beginning balance (shares)			3,531,359
Granted (shares)			1,184,880
Exercised (shares)			(153,601)
Expired or terminated (shares)			(846,059)
Ending balance (shares)			3,716,579
2007 Equity Plan
Stock Options
Beginning balance (shares)			2,590,373
Granted (shares)			1,047,087
Exercised (shares)			(150,789)
Expired or terminated (shares)			(704,885)
Ending balance (shares)			2,781,786
Restricted Stock Units
Remaining number of shares available for future grants			2,548,513
2013 Lumara Equity Plan
Stock Options
Beginning balance (shares)			125,536
Granted (shares)			35,400
Exercised (shares)			(2,812)
Expired or terminated (shares)			(33,674)
Ending balance (shares)			124,450
Restricted Stock Units
Remaining number of shares available for future grants			18,242
Inducement Grants
Stock Options
Beginning balance (shares)			815,450
Granted (shares)			102,393
Exercised (shares)			0
Expired or terminated (shares)			(107,500)
Ending balance (shares)			810,343
RSUs
Restricted Stock Units
Outstanding at beginning of year (shares)			1,069,775
Granted (shares)			816,887
Vested (shares)			(438,284)
Expired or terminated (in shares)			(319,843)
Outstanding at end of year (shares)			1,128,535
Compensation expense, period for recognition			1 year 9 months 18 days
RSUs \| 2007 Equity Plan
Restricted Stock Units
Outstanding at beginning of year (shares)			966,623
Granted (shares)			766,869
Vested (shares)			(375,470)
Expired or terminated (in shares)			(316,881)
Outstanding at end of year (shares)			1,041,141
RSUs \| 2013 Lumara Equity Plan
Restricted Stock Units
Outstanding at beginning of year (shares)			11,611
Granted (shares)			1,600
Vested (shares)			(10,650)
Expired or terminated (in shares)			(460)
Outstanding at end of year (shares)			2,101
RSUs \| Inducement Grants
Restricted Stock Units
Outstanding at beginning of year (shares)			91,541
Granted (shares)			48,418
Vested (shares)			(52,164)
Expired or terminated (in shares)			(2,502)
Outstanding at end of year (shares)			85,293
Award vesting period			3 years
Performance Restricted Stock Units (RSUs)
Restricted Stock Units
Compensation expense, period for recognition			1 year 9 months
Performance Restricted Stock Units (RSUs) \| 2007 Equity Plan
Restricted Stock Units
Granted (shares)	206,250	191,250
Award vesting period			3 years
Compensation expense, period for recognition			3 years
March 2018 \| Performance Restricted Stock Units (RSUs) \| 2007 Equity Plan
Restricted Stock Units
Granted (shares)			188,250
Fair value, performance- based RSUs			$ 3.5
February 2017 \| Performance Restricted Stock Units (RSUs) \| 2007 Equity Plan
Restricted Stock Units
Remaining number of shares available for future grants			153,750
Fair value, performance- based RSUs			$ 3.1