Note 5 - Accumulated Other Comprehensive Income - Reclassifications Out of AOCI (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Other-than-temporary impairment of marketable securities		$ (100)		$ (200)
Income before income taxes	$ 76,616	51,894	$ 127,148	88,254
Provision for income taxes	(12,717)	(18,023)	(24,485)	(32,134)
Net income	63,899	33,871	102,663	56,120
Homebuilding Segment [Member]
Homebuilding: Interest and other income	1,774	2,847	3,633	5,174
Other-than-temporary impairment of marketable securities		(1)		(51)
Income before income taxes	62,337	40,163	102,798	65,514
Financial Services Segment [Member]
Other-than-temporary impairment of marketable securities		(80)		(131)
Interest and other income	2,518	1,238	2,385	2,217
Income before income taxes	14,279	11,731	24,350	22,740
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Income before income taxes		1,116		1,576
Provision for income taxes		(424)		(599)
Net income		692		977
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		889		1,411
Other-than-temporary impairment of marketable securities		(1)		(51)
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		(80)		(131)
Interest and other income		$ 308		$ 347