Note 10 - Fair Value Disclosures (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Unconsolidated Joint Ventures [Member]
Equity Method Investment, Other than Temporary Impairment	$ 2,300	$ 0
Senior Notes [Member] \| Senior Notes Due 2022 [Member]
Debt Instrument, Unamortized Discount, Total	1,000		$ 1,100
Debt Instrument, Unamortized Premium, Total	800		900
Debt Issuance Costs, Net, Total	$ 2,600		$ 3,000

Amount, after accumulated amortization, of debt discount.

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