Note 5 - Accumulated Other Comprehensive Income - Reclassifications Out of AOCI (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Other-than-temporary impairment of marketable securities	$ 0	$ 0	$ 0	$ (200,000)
Income before income taxes	67,420,000	89,680,000	194,568,000	177,934,000
Provision for income taxes	(14,028,000)	(28,517,000)	(38,513,000)	(60,651,000)
Net income	53,392,000	61,163,000	156,055,000	117,283,000
Homebuilding Segment [Member]
Homebuilding: Interest and other income	1,953,000	54,548,000	5,586,000	59,722,000
Other-than-temporary impairment of marketable securities				(51,000)
Income before income taxes	52,983,000	80,169,000	155,781,000	145,683,000
Financial Services Segment [Member]
Other-than-temporary impairment of marketable securities		(29,000)		(160,000)
Interest and other income	4,234,000	925,000	6,619,000	3,142,000
Income before income taxes	14,437,000	9,511,000	38,787,000	32,251,000
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Income before income taxes		52,182,000		53,758,000
Provision for income taxes		(19,829,000)		(20,428,000)
Net income		32,353,000		33,330,000
Reclassification out of Accumulated Other Comprehensive Income [Member] | Homebuilding Segment [Member] | Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Homebuilding: Interest and other income		52,211,000		53,622,000
Other-than-temporary impairment of marketable securities				(51,000)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Financial Services Segment [Member] | Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Other-than-temporary impairment of marketable securities		(29,000)		(160,000)
Interest and other income				$ 347,000