Note 21 - Supplemental Guarantor Information - Supplemental Condensed Combining Statements of Operations (Details) - USD ($)	3 Months Ended						9 Months Ended
	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Sep. 30, 2017	Sep. 30, 2016
Inventory impairments							$ (9,390,000)	$ (6,300,000)
Other-than-temporary impairment of marketable securities	$ 0			$ (300,000)			(211,000)	(1,045,000)
Pretax income (loss)	89,680,000			38,052,000			177,934,000	92,783,000
(Provision) benefit for income taxes	(28,517,000)			(11,693,000)			(60,651,000)	(29,948,000)
Net income	61,163,000			26,359,000			117,283,000	62,835,000
Other comprehensive income related to available-for-sale securities, net of tax	(23,175,000)			1,028,000			(19,245,000)	3,871,000
Comprehensive income	37,988,000			27,387,000			98,038,000	66,706,000
Homebuilding Segment [Member]
Revenues	586,287,000			578,012,000			1,798,984,000	1,546,267,000
Cost of sales	(486,406,000)			(483,829,000)			(1,495,838,000)	(1,291,570,000)
Inventory impairments	(4,540,000)		$ (4,850,000)	(4,700,000)	$ (1,600,000)		(9,390,000)	(6,300,000)
Gross margin	95,341,000			89,483,000			293,756,000	248,397,000
Selling, general, and administrative expenses	(69,102,000)			(61,904,000)			(206,109,000)	(182,621,000)
Equity income of subsidiaries
Interest and other income	54,548,000			1,869,000			59,722,000	5,358,000
Other expense	(618,000)			(1,558,000)			(1,635,000)	(2,463,000)
Other-than-temporary impairment of marketable securities				(215,000)			(51,000)	(934,000)
Pretax income (loss)	80,169,000			27,675,000			145,683,000	67,737,000
Financial Services Segment [Member]
Other-than-temporary impairment of marketable securities	(29,000)			(111,000)			(160,000)	(111,000)
Pretax income (loss)	9,511,000			10,377,000			32,251,000	25,046,000
Reportable Legal Entities [Member] | Parent Company [Member]
Pretax income (loss)	75,165,000			23,707,000			123,650,000	52,426,000
(Provision) benefit for income taxes	(14,002,000)			2,652,000			(6,367,000)	10,409,000
Net income	61,163,000			26,359,000			117,283,000	62,835,000
Other comprehensive income related to available-for-sale securities, net of tax	(23,175,000)			1,028,000			(19,245,000)	3,871,000
Comprehensive income	37,988,000			27,387,000			98,038,000	66,706,000
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Pretax income (loss)	38,674,000			34,972,000			125,391,000	97,396,000
(Provision) benefit for income taxes	(11,168,000)			(10,616,000)			(42,742,000)	(31,438,000)
Net income	27,506,000			24,356,000			82,649,000	65,958,000
Other comprehensive income related to available-for-sale securities, net of tax
Comprehensive income	27,506,000			24,356,000			82,649,000	65,958,000
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Pretax income (loss)	9,170,000			10,084,000			31,362,000	23,951,000
(Provision) benefit for income taxes	(3,347,000)			(3,729,000)			(11,542,000)	(8,919,000)
Net income	5,823,000			6,355,000			19,820,000	15,032,000
Other comprehensive income related to available-for-sale securities, net of tax	927,000			310,000			2,217,000	680,000
Comprehensive income	6,750,000			6,665,000			22,037,000	15,712,000
Reportable Legal Entities [Member] | Homebuilding Segment [Member] | Parent Company [Member]
Revenues
Cost of sales
Inventory impairments
Gross margin
Selling, general, and administrative expenses	(11,911,000)			(8,268,000)			(36,539,000)	(31,598,000)
Equity income of subsidiaries	33,329,000			30,711,000			102,469,000	80,990,000
Interest and other income	53,740,000			1,478,000			57,748,000	3,970,000
Other expense	7,000			1,000			23,000	(2,000)
Other-than-temporary impairment of marketable securities				(215,000)			(51,000)	(934,000)
Pretax income (loss)	75,165,000			23,707,000			123,650,000	52,426,000
Reportable Legal Entities [Member] | Homebuilding Segment [Member] | Guarantor Subsidiaries [Member]
Revenues	586,287,000			578,012,000			1,798,984,000	1,546,267,000
Cost of sales	(486,406,000)			(483,829,000)			(1,495,838,000)	(1,291,270,000)
Inventory impairments	(4,540,000)			(4,700,000)			(9,390,000)	(6,300,000)
Gross margin	95,341,000			89,483,000			293,756,000	248,697,000
Selling, general, and administrative expenses	(56,983,000)			(53,452,000)			(168,988,000)	(150,492,000)
Equity income of subsidiaries
Interest and other income	941,000			500,000			2,281,000	1,652,000
Other expense	(625,000)			(1,559,000)			(1,658,000)	(2,461,000)
Other-than-temporary impairment of marketable securities
Pretax income (loss)	38,674,000			34,972,000			125,391,000	97,396,000
Reportable Legal Entities [Member] | Homebuilding Segment [Member] | Non-Guarantor Subsidiaries [Member]
Revenues
Cost of sales								(300,000)
Inventory impairments
Gross margin								(300,000)
Selling, general, and administrative expenses
Equity income of subsidiaries
Interest and other income	1,000			1,000			5,000	4,000
Other expense
Other-than-temporary impairment of marketable securities
Pretax income (loss)	1,000			1,000			5,000	(296,000)
Reportable Legal Entities [Member] | Financial Services Segment [Member] | Parent Company [Member]
Pretax income (loss)
Reportable Legal Entities [Member] | Financial Services Segment [Member] | Guarantor Subsidiaries [Member]
Pretax income (loss)
Reportable Legal Entities [Member] | Financial Services Segment [Member] | Non-Guarantor Subsidiaries [Member]
Pretax income (loss)	9,169,000			10,083,000			31,357,000	24,247,000
Consolidation, Eliminations [Member]
Pretax income (loss)	(33,329,000)			(30,711,000)			(102,469,000)	(80,990,000)
(Provision) benefit for income taxes
Net income	(33,329,000)			(30,711,000)			(102,469,000)	(80,990,000)
Other comprehensive income related to available-for-sale securities, net of tax	(927,000)			(310,000)			(2,217,000)	(680,000)
Comprehensive income	(34,256,000)			(31,021,000)			(104,686,000)	(81,670,000)
Consolidation, Eliminations [Member] | Homebuilding Segment [Member]
Revenues
Cost of sales
Inventory impairments
Gross margin
Selling, general, and administrative expenses	(208,000)			(184,000)			(582,000)	(531,000)
Equity income of subsidiaries	(33,329,000)			(30,711,000)			(102,469,000)	(80,990,000)
Interest and other income	(134,000)			(110,000)			(312,000)	(268,000)
Other expense
Other-than-temporary impairment of marketable securities
Pretax income (loss)	(33,671,000)			(31,005,000)			(103,363,000)	(81,789,000)
Consolidation, Eliminations [Member] | Financial Services Segment [Member]
Pretax income (loss)	$ 342,000			$ 294,000			$ 894,000	$ 799,000