Note 22 - Results of Quarterly Operations (Unaudited) (Restated for Stock Dividends) - Results of Quarterly Operations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues	$ 881,875	$ 785,638	$ 770,980	$ 626,723	$ 724,114	$ 603,751	$ 668,044	$ 581,705	$ 3,065,216	$ 2,577,614	$ 2,326,844
Asset impairments	$ (10,002)	$ (11,098)	$ (200)	$ (550)	$ (620)	$ (4,540)		$ (4,850)
Gross margin from home sales (including impairments)	18.10%	17.70%	19.10%	18.20%	17.30%	16.30%	16.80%	15.90%
Homebuilding selling, general and administrative expenses	$ 93,366	$ 83,523	$ 81,571	$ 71,341	$ 81,379	$ 69,102	$ 70,709	$ 66,298
Pretax income	69,286	67,420	76,616	50,532	51,798	89,680	51,894	36,360	263,854	229,732	151,781
Net income	$ 54,725	$ 53,392	$ 63,899	$ 38,764	$ 24,552	$ 61,163	$ 33,871	$ 22,249	$ 210,780	$ 141,835	$ 103,211
Basic (in dollars per share)	$ 0.97	$ 0.94	$ 1.13	$ 0.69	$ 0.44	$ 1.09	$ 0.61	$ 0.40	$ 3.74	$ 2.54	$ 1.86
Diluted (in dollars per share)	$ 0.95	$ 0.93	$ 1.12	$ 0.68	$ 0.43	$ 1.07	$ 0.59	$ 0.39	$ 3.66	$ 2.48	$ 1.85
Home Building [Member]
Revenues	$ 858,488	$ 766,027	$ 749,608	$ 607,688	$ 702,649	$ 584,947	$ 647,620	$ 563,479