Note 11 - Net Income (Loss) Attributable to Controlling Interests Per Common Share (Details Textual)	3 Months Ended
Mar. 31, 2019 $ / shares shares	Mar. 31, 2018 shares
Weighted Average Number of Shares, Restricted Stock	397,566	184,196
Five Point Eight Seven Five Percent Convertible Senior Notes Due Two Thousand Thirty Five [Member]
Incremental Common Shares Attributable to Conversion of Debt Securities, Total	0	0
Debt Instrument, Convertible, Conversion Price \| $ / shares	$ 24.61
Debt Instrument, Convertible, Number of Equity Instruments	3,600,000

The price per share of the conversion feature embedded in the debt instrument.

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The number of equity instruments that the holder of the debt instrument would receive if the debt was converted to equity.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

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Number of shares of restricted stock determined by relating the portion of time within a reporting period that restricted shares have been outstanding to the total time in that period. Restricted shares are subject to sales, contractual, regulatory or other restrictions that prevent or inhibit the holder from freely disposing of them before the restriction ends.

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