Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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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.

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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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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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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EQUITY INCENTIVE PLAN (Summary of Stock Option Activity) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Number of Options
Outstanding at beginning of period (in shares)			224,895
Granted (in shares)			285,364
Forfeited (in shares)			(9,017)
Outstanding at end of period (in shares)	501,242		501,242
Exercisable at end of period (in shares)	99,047		99,047
Weighted-Average Exercise Price
Outstanding at beginning of period (in dollars per share)			$ 15.90
Granted (in dollars per share)			2.37
Forfeited (in dollars per share)			6.92
Outstanding at end of period (in dollars per share)	$ 8.29		8.29
Exercisable at end of period (in dollars per share)	$ 20.22		$ 20.22
Stock-based compensation	$ 0.1	$ 0.1	$ 0.3	$ 0.2
Stock Options [Member]
Number of Options
Granted (in shares)				219,101
Forfeited (in shares)				(7,530)
Weighted-Average Exercise Price
Granted (in dollars per share)				$ 10.65
Forfeited (in dollars per share)				$ 42.60
Stock Options [Member] \| Performance-based milestone vesting
Number of Options
Granted (in shares)			100,000