Note 6 - Other Assets (Details Textual) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Cost Method Investments, Fair Value Disclosure	$ 1,932	$ 1,192

Fair value portion of investments accounted under the cost method.

No definition available.

Name:	us-gaap_CostMethodInvestmentsFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant