Note 4 - Real Estate Inventories - Inventory Impairments (Details) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Cost of sales, impairments										$ 10,200	$ 10,000	$ 2,200
Remaining carrying value of inventory impaired at year end		$ 81,622				$ 57,845				$ 81,622	$ 57,845	$ 5,921
Number of projects impaired during the year										3	2	1
Total number of projects subject to periodic impairment review during the year (1)	[1]									27	26	26
Home Building [Member]
Cost of sales, impairments		6,600	$ 1,700	$ 0	$ 0	$ 10,000	$ 0	$ 0	$ 0	$ 8,300	$ 10,000	$ 2,200
Land [Member]
Cost of sales, impairments		$ 0	$ 1,900	$ 0	$ 0					$ 1,900	$ 0	$ 0

[1] Represents the peak number of real estate projects that we had during each respective year. The number of projects outstanding at the end of each year may be less than the number of projects listed herein.