Note L - Fair Value of Financial Instruments - Reconciliation of Beginning and Ending Balances for Derivative and Warrant Liability Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
|
| Balance at beginning of period | $ 37,839 | $ 15,966 |
| Reclassification of 2013 warrants to equity | (1,110) | |
| Exercise of warrants | (756) | (4,293) |
| Adjustment to fair value | (32,465) | 27,276 |
| Balance at end of period | $ 4,618 | $ 37,839 |