Note 5 - Other Intangible Assets - Carrying Value of Definite Lived Intangible Assets (Details) - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
|
| Finite-Lived Intangible Asset, Useful Life | ||
| Gross amount | $ 2,987 | $ 2,987 |
| Accumulated amortization | (2,669) | (2,351) |
| Net balance | $ 318 | 636 |
| Patents [Member] | ||
| Finite-Lived Intangible Asset, Useful Life | 14 years | |
| Gross amount | $ 429 | 429 |
| Accumulated amortization | (429) | (429) |
| Net balance | ||
| Noncompete Agreements [Member] | ||
| Finite-Lived Intangible Asset, Useful Life | 5 years | |
| Gross amount | $ 512 | 512 |
| Accumulated amortization | (449) | (387) |
| Net balance | $ 63 | 125 |
| Customer Lists [Member] | ||
| Finite-Lived Intangible Asset, Useful Life | 5 years | |
| Gross amount | $ 2,046 | 2,046 |
| Accumulated amortization | (1,791) | (1,535) |
| Net balance | $ 255 | $ 511 |