Organization and Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2018 |
Jun. 30, 2017 |
Jun. 30, 2018 |
Jun. 30, 2017 |
Mar. 31, 2016 |
|
| Schedule of Organization and Summary of Significant Accounting Policies [Line Items] | |||||
| Less change in fair value of warrant liability | $ 0 | $ 190 | $ 0 | $ 612 | |
| Investments, Fair Value Disclosure | $ 1,600 | $ 1,600 | |||
| Warrant Expiration Date | Apr. 18, 2018 | ||||
| Adjustments for New Accounting Pronouncement [Member] | |||||
| Schedule of Organization and Summary of Significant Accounting Policies [Line Items] | |||||
| Deferred Tax Assets Unrecognized Tax Benefit | $ 12,000 | ||||