Note 13 - Recent Accounting Pronouncements (Details Textual) - USD ($) $ in Thousands	Jul. 01, 2019	Sep. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Operating Lease, Right-of-Use Asset		$ 1,336
Operating Lease, Liability, Total		1,522
Deferred Compensation Share-based Arrangements, Liability, Current		182		3,018
Additional Paid in Capital, Ending Balance		$ 162,590		$ 180,862
Accounting Standards Update 2016-02 [Member]
Operating Lease, Right-of-Use Asset			$ 1,600
Operating Lease, Liability, Total			1,900
Accounting Standards Update 2018-07 [Member]
Deferred Compensation Share-based Arrangements, Liability, Current			(2,100)
Additional Paid in Capital, Ending Balance			$ 2,100
Accounting Standards Update 2018-15 [Member]
Implementation Costs Capitalized	$ 1,900