Note 25 - Supplemental Guarantor Information - Supplemental Condensed Combining Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	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, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues	$ 1,104,468	$ 772,662	$ 751,441	$ 664,682	$ 881,875	$ 785,638	$ 770,980	$ 626,723					$ 3,293,253	$ 3,065,216	$ 2,577,614
Inventory impairments	(325)	0	0	(610)	(10,002)	(11,098)	(200)	(550)	$ (620)	$ (4,540)	$ 0	$ (4,850)	(935)	(21,850)	(10,010)
Selling, general and administrative expenses	(105,101)	(92,716)	(82,712)	(82,261)	(93,366)	(83,523)	(81,571)	(71,341)
Pretax income (loss)													304,989	263,854	229,732
Provision for income taxes													(66,677)	(53,074)	(87,897)
Net Income	$ 92,589	$ 50,580	$ 54,593	$ 40,550	$ 54,725	$ 53,392	$ 63,899	$ 38,764					238,312	210,780	141,835
Other comprehensive loss related to available-for-sale securities, net of tax													0	0	(18,079)
Comprehensive income													238,312	210,780	123,756
Homebuilding Segment [Member]
Revenues													3,205,248	2,981,811	2,503,242
Cost of Sales													(2,600,196)	(2,415,139)	(2,078,273)
Inventory impairments													(935)	(21,850)	(10,010)
Gross margin													604,117	544,822	414,959
Selling, general and administrative expenses													(362,790)	(329,801)	(287,488)
Equity income of subsidiaries													0	0	0
Interest and other income													9,070	7,718	61,336
Other expense													(5,635)	(5,245)	(2,868)
Pretax income (loss)													244,762	217,494	185,939
Other comprehensive loss related to available-for-sale securities, net of tax													0	0	(18,079)
Financial Services Segment [Member]
Revenues													88,005	83,405	74,372
Interest and other income													17,223	1,155	3,955
Pretax income (loss)													60,227	46,360	43,793
Reportable Legal Entities [Member] | Parent Company [Member]
Pretax income (loss)													223,912	197,772	150,950
Provision for income taxes													14,400	13,008	(9,115)
Net Income													238,312	210,780	141,835
Comprehensive income													238,312	210,780	123,756
Reportable Legal Entities [Member] | Parent Company [Member] | Homebuilding Segment [Member]
Revenues													0	0	0
Cost of Sales													0	0	0
Inventory impairments													0	0	0
Gross margin													0	0	0
Selling, general and administrative expenses													(71,720)	(64,824)	(52,252)
Equity income of subsidiaries													286,606	254,723	144,190
Interest and other income													8,996	7,843	59,042
Other expense													30	30	(30)
Pretax income (loss)													223,912	197,772	150,950
Other comprehensive loss related to available-for-sale securities, net of tax													0	0	(18,079)
Reportable Legal Entities [Member] | Parent Company [Member] | Financial Services Segment [Member]
Pretax income (loss)													0	0	0
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Pretax income (loss)													309,187	276,101	180,427
Provision for income taxes													(67,595)	(55,539)	(64,051)
Net Income													241,592	220,562	116,376
Comprehensive income													241,592	220,562	116,376
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member] | Homebuilding Segment [Member]
Revenues													3,205,248	2,981,811	2,503,242
Cost of Sales													(2,600,196)	(2,415,139)	(2,078,371)
Inventory impairments													(935)	(21,850)	(10,010)
Gross margin													604,117	544,822	414,861
Selling, general and administrative expenses													(290,507)	(264,475)	(234,430)
Equity income of subsidiaries													0	0	0
Interest and other income													1,242	1,029	2,834
Other expense													(5,665)	(5,275)	(2,838)
Pretax income (loss)													309,187	276,101	180,427
Other comprehensive loss related to available-for-sale securities, net of tax													0	0	0
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member] | Financial Services Segment [Member]
Pretax income (loss)													0	0	0
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Pretax income (loss)													58,496	44,704	42,545
Provision for income taxes													(13,482)	(10,543)	(14,731)
Net Income													45,014	34,161	27,814
Comprehensive income													45,014	34,161	31,196
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member] | Homebuilding Segment [Member]
Revenues													0	0	0
Cost of Sales													0	0	98
Inventory impairments													0	0	0
Gross margin													0	0	98
Selling, general and administrative expenses													0	0	0
Equity income of subsidiaries													0	0	0
Interest and other income													0	4	6
Other expense													0	0	0
Pretax income (loss)													0	4	104
Other comprehensive loss related to available-for-sale securities, net of tax													0	0	3,382
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member] | Financial Services Segment [Member]
Pretax income (loss)													58,496	44,700	42,441
Consolidation, Eliminations [Member]
Pretax income (loss)													(286,606)	(254,723)	(144,190)
Provision for income taxes													0	0	0
Net Income													(286,606)	(254,723)	(144,190)
Comprehensive income													(286,606)	(254,723)	(147,572)
Consolidation, Eliminations [Member] | Homebuilding Segment [Member]
Revenues													0	0	0
Cost of Sales													0	0	0
Inventory impairments													0	0	0
Gross margin													0	0	0
Equity income of subsidiaries													(286,606)	(254,723)	(144,190)
Interest and other income													(1,168)	(1,158)	(546)
Other expense													0	0	0
Pretax income (loss)													(288,337)	(256,383)	(145,542)
Other comprehensive loss related to available-for-sale securities, net of tax													0	0	(3,382)
Consolidation, Eliminations [Member] | Financial Services Segment [Member]
Pretax income (loss)													1,731	1,660	1,352
Segment Reconciling Items [Member] | Homebuilding Segment [Member]
Selling, general and administrative expenses													$ (563)	$ (502)	$ (806)