Note 4 - Segment Reporting - Reconciliation of Pretax Operating Income From Segments to Consolidated (Details) - USD ($) $ 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
Income before income taxes		$ 69,286	$ 67,420	$ 76,616	$ 50,532	$ 51,798	$ 89,680	$ 51,894	$ 36,360	$ 263,854	$ 229,732	$ 151,781
Homebuilding Segment [Member]
Income before income taxes										217,494	185,939	115,378
Homebuilding Segment [Member] | Corporate, Non-Segment [Member]
Income before income taxes	[1]									(58,656)	5,374	(36,269)
Homebuilding Segment [Member] | Reportable Segment, West [Member] | Operating Segments [Member]
Income before income taxes										128,829	79,719	73,594
Homebuilding Segment [Member] | Reportable Segment, Mountain [Member] | Operating Segments [Member]
Income before income taxes										134,710	86,428	73,104
Homebuilding Segment [Member] | Reportable Segment, East [Member] | Operating Segments [Member]
Income before income taxes										12,611	14,418	4,949
Financial Services Segment [Member]
Income before income taxes										46,360	43,793	36,403
Financial Services Segment [Member] | Mortgage Operations [Member] | Operating Segments [Member]
Income before income taxes										31,920	28,628	23,845
Financial Services Segment [Member] | Other Financial Services [Member] | Operating Segments [Member]
Income before income taxes										$ 14,440	$ 15,165	$ 12,558

[1] The pretax gain for the year ended December 31, 2017 was driven by $53.6 million in realized gains due to the sale of investments.