Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Revenue earned during the period from the leasing or otherwise lending to a third party the entity's rights or title to certain property. Royalty revenue is derived from a percentage or stated amount of sales proceeds or revenue generated by the third party using the entity's property. Examples of property from which royalties may be derived include patents and oil and mineral rights.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Revenue Recognition (Details Narrative) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Royalty revenue	$ 31	$ 29	$ 58	$ 57
License Agreement [Member]
Deferred revenue	313		313		$ 348
Revenue recognized	$ 18	$ 17	$ 35	$ 34
Deferred Revenue, Description			Approximately $34,000 of revenue will be recognized in the remaining six months of fiscal year 2017 and approximately $69,000 of revenue will be recognized in each of the years ended December 31, 2018 through 2021.
License Agreement [Member] \| Remaining Nine Months of Fiscal Year 2017 [Member]
Revenue recognized			$ 34
License Agreement [Member] \| December 31, 2018 through 2021 [Member]
Revenue recognized			69
Bellco License Agreement [Member]
Revenue recognized			$ 2,763