Note 7 - Leases (Tables)	9 Months Ended
	Sep. 30, 2019
Notes Tables
Lessee, Lease, Liability, Maturity [Table Text Block]	<div style="display: inline; font-family: times new roman; font-size: 10pt"><table style="border-collapse: collapse; font: 10pt Times New Roman, Times, Serif; margin-left: 0.5in; min-; min-width: 700px;" cellspacing="0" cellpadding="0"> <tr style="vertical-align: bottom"> <td style="font-size: 10pt; font-weight: bold; border-bottom: Black 1pt solid; white-space: nowrap">Remaining Maturities of Lease Liabilities <br />Year Ending December 31,</td> <td style="font-size: 10pt; font-weight: bold; padding-bottom: 1pt; white-space: nowrap"> </td> <td colspan="3" style="font-size: 10pt; font-weight: bold; text-align: center; border-bottom: Black 1pt solid; white-space: nowrap">Operating Leases</td> </tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 86%; font-size: 10pt; text-align: left">2019</td> <td style="width: 2%; font-size: 10pt"> </td> <td style="width: 1%; font-size: 10pt; text-align: left">$</td> <td style="width: 10%; font-size: 10pt; text-align: right"><div style="display: inline; font-style: italic; font-weight: inherit; font-style: normal;">400</div></td> <td style="width: 1%; font-size: 10pt; text-align: left"> </td> </tr> <tr style="vertical-align: bottom; background-color: White"> <td style="font-size: 10pt; text-align: left">2020</td> <td style="font-size: 10pt"> </td> <td style="font-size: 10pt; text-align: left"> </td> <td style="font-size: 10pt; text-align: right"><div style="display: inline; font-style: italic; font-weight: inherit; font-style: normal;">1,450</div></td> <td style="font-size: 10pt; text-align: left"> </td> </tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="font-size: 10pt; text-align: left">2021</td> <td style="font-size: 10pt"> </td> <td style="font-size: 10pt; text-align: left"> </td> <td style="font-size: 10pt; text-align: right"><div style="display: inline; font-style: italic; font-weight: inherit; font-style: normal;">580</div></td> <td style="font-size: 10pt; text-align: left"> </td> </tr> <tr style="vertical-align: bottom; background-color: White"> <td style="font-size: 10pt; text-align: left">2022</td> <td style="font-size: 10pt"> </td> <td style="font-size: 10pt; text-align: left"> </td> <td style="font-size: 10pt; text-align: right"><div style="display: inline; font-style: italic; font-weight: inherit; font-style: normal;">519</div></td> <td style="font-size: 10pt; text-align: left"> </td> </tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="font-size: 10pt; text-align: left">2023</td> <td style="font-size: 10pt"> </td> <td style="font-size: 10pt; text-align: left"> </td> <td style="font-size: 10pt; text-align: right"><div style="display: inline; font-style: italic; font-weight: inherit; font-style: normal;">512</div></td> <td style="font-size: 10pt; text-align: left"> </td> </tr> <tr style="vertical-align: bottom; background-color: White"> <td style="font-size: 10pt; text-align: left">Thereafter</td> <td style="font-size: 10pt; padding-bottom: 1pt"> </td> <td style="border-bottom: Black 1pt solid; font-size: 10pt; text-align: left"> </td> <td style="border-bottom: Black 1pt solid; font-size: 10pt; text-align: right"><div style="display: inline; font-style: italic; font-weight: inherit; font-style: normal;">7,765</div></td> <td style="border-bottom: Black 1pt solid; font-size: 10pt; text-align: left"> </td> </tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="font-size: 10pt; text-align: left; padding-left: 12.1pt">Total lease payments</td> <td style="font-size: 10pt"> </td> <td style="font-size: 10pt; text-align: left"> </td> <td style="font-size: 10pt; text-align: right"><div style="display: inline; font-style: italic; font-weight: inherit; font-style: normal;">11,226</div></td> <td style="font-size: 10pt; text-align: left"> </td> </tr> <tr style="vertical-align: bottom; background-color: White"> <td style="font-size: 10pt; text-align: left">Less imputed interest</td> <td style="font-size: 10pt; padding-bottom: 1pt"> </td> <td style="border-bottom: Black 1pt solid; font-size: 10pt; text-align: left"> </td> <td style="border-bottom: Black 1pt solid; font-size: 10pt; text-align: right"><div style="display: inline; font-style: italic; font-weight: inherit; font-style: normal;">6,231</div></td> <td style="border-bottom: Black 1pt solid; font-size: 10pt; text-align: left"> </td> </tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="font-size: 10pt; padding-bottom: 2.5pt; padding-left: 12.1pt">Total</td> <td style="font-size: 10pt; padding-bottom: 2.5pt"> </td> <td style="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: left">$</td> <td style="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: right"><div style="display: inline; font-style: italic; font-weight: inherit; font-style: normal;">4,995</div></td> <td style="border-bottom: Black 2.5pt double; font-size: 10pt; text-align: left"> </td> </tr> </table></div>