v3.8.0.1

Note 2 - Investments and Fair Value Measurement - Fair Value of Financial Assets and Liabilities by Level Within Fair Value Hierarchy (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Assets, fair value | $ 30,704 | $ 30,477
Liabilities, fair value | 207 | 412
Contingent Put Option Liability [Member] |  |
Liabilities, fair value | 207 | 124
PIPE Warrants [Member] |  |
Liabilities, fair value |  | 288
Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value |  |
Liabilities, fair value |  |
Fair Value, Inputs, Level 1 [Member] | Contingent Put Option Liability [Member] |  |
Liabilities, fair value |  |
Fair Value, Inputs, Level 1 [Member] | PIPE Warrants [Member] |  |
Liabilities, fair value |  |
Fair Value, Inputs, Level 2 [Member] |  |
Assets, fair value | 30,704 | 30,477
Liabilities, fair value |  |
Fair Value, Inputs, Level 2 [Member] | Contingent Put Option Liability [Member] |  |
Liabilities, fair value |  |
Fair Value, Inputs, Level 2 [Member] | PIPE Warrants [Member] |  |
Liabilities, fair value |  |
Fair Value, Inputs, Level 3 [Member] |  |
Assets, fair value |  |
Liabilities, fair value | 207 | 412
Fair Value, Inputs, Level 3 [Member] | Contingent Put Option Liability [Member] |  |
Liabilities, fair value | 207 | 124
Fair Value, Inputs, Level 3 [Member] | PIPE Warrants [Member] |  |
Liabilities, fair value |  | 288
U.S. Government Agency Obligations [Member] |  |
Assets, fair value | 30,704 | 30,477
U.S. Government Agency Obligations [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Assets, fair value |  |
U.S. Government Agency Obligations [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Assets, fair value | 30,704 | 30,477
U.S. Government Agency Obligations [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Assets, fair value |  |

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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