Note 17 - Supplemental Disclosure of Cash Flow Information - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplemental disclosures of cash flow information
Interest paid, net of amounts capitalized	$ 0	$ 0	$ 0
Income taxes paid	270	7,110	14,050
Assets assumed from unconsolidated joint ventures	0	0	26,613
Liabilities and equity assumed from unconsolidated joint ventures	$ 0	$ 0	$ 27,608