Note 6 - Investment in and Transactions with Unconsolidated Subsidiaries (Tables)
|3 Months Ended|
Mar. 31, 2019
|Equity Method Investments [Table Text Block]||
Tabular disclosure of equity method investments including, but not limited to, name of each investee or group of investments, percentage ownership, difference between recorded amount of an investment and the value of the underlying equity in the net assets, and summarized financial information.
Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef