CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) [Abstract]
Revenue	$ 38	$ 16	$ 46	$ 22
Operating expense:
Research and development	986	1,186	1,921	2,191
Selling, general and administrative	3,604	5,292	8,310	11,901
Total operating expense	4,590	6,478	10,231	14,092
Loss from operations	(4,552)	(6,462)	(10,185)	(14,070)
Interest income, net	27	12	54	20
Loss before taxes	(4,525)	(6,450)	(10,131)	(14,050)
Benefit (expense) for income tax	395	0	393	(5)
Net loss	$ (4,130)	$ (6,450)	$ (9,738)	$ (14,055)
Basic and diluted loss per share (in dollars per share)	$ (0.06)	$ (0.10)	$ (0.14)	$ (0.23)
Weighted average shares outstanding basic and diluted (in shares)	68,258	61,532	67,929	60,835

The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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