DEFERRED GRANT INCOME (Details Textual) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018	Jul. 31, 2017
Grants Receivable			$ 15,912
California Institute Of Regenerative Medicine [Member]
Proceeds from Grantors	$ 12,550	$ 9,050
Research and Development Arrangement, Contract to Perform for Others, Compensation Earned	$ 1,347	$ 6,267

Carrying amount as of the balance sheet date of amounts due under the terms of governmental, corporate, or foundation grants.

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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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- Definition

Cash received from grantors during the current period related to operating activities. This element represents receipts from a guarantor for the amount of guarantee provided.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 25
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The amount of compensation earned (contract income) under a research and development arrangement accounted for as a contract to perform research and development for others.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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