Senior Notes, Secured, and Subordinated Indebtedness - Consolidating Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating revenue
Sales									$ 1,081,428	$ 858,951	$ 540,002
Construction services									25,124	37,728	32,533
Management fees									0	0	0
Operating revenue	$ 397,162	$ 246,811	$ 247,740	$ 189,715	$ 352,479	$ 196,305	$ 169,868	$ 140,299	1,106,552	896,679	572,535
Operating costs
Cost of sales									(880,724)	(679,060)	(420,188)
Construction services									(21,181)	(30,700)	(25,598)
Sales and marketing									(61,539)	(45,903)	(26,102)
General and administrative									(59,161)	(54,626)	(40,770)
Transaction expenses									0	(5,832)	0
Amortization of intangible assets									(957)	(1,814)	(1,854)
Other									(1,972)	(2,874)	(2,166)
Operating costs									(1,025,534)	(820,809)	(516,678)
(Loss) income from subsidiaries									0	0	0
Operating income									81,018	75,870	55,857
Equity in income of unconsolidated joint ventures									3,239	555	0
Interest expense, net of amounts capitalized									0	0	(2,602)
Other income (expense), net									2,810	1,898	510
(Loss) income before reorganization items and provision for income taxes									87,067	78,323	53,765
Reorganization items, net									0	0	(464)
(Loss) income before provision for income taxes									87,067	78,323	53,301
Benefit (provision) for income taxes									(26,806)	(23,797)	82,302
Net income	$ 27,128	$ 12,277	$ 13,250	$ 7,606	$ 20,810	$ 7,622	$ 14,752	$ 11,342	60,261	54,526	135,603
Less: Net income attributable to noncontrolling interests									(2,925)	(9,901)	(6,471)
Net income attributable to William Lyon Homes									57,336	44,625	129,132
Preferred stock dividends									0	0	(1,528)
Net income available to common stockholders									57,336	44,625	127,604
Delaware Lyon
Operating revenue
Sales									0	0	0
Construction services									0	0	0
Management fees									0	0	0
Operating revenue									0	0	0
Operating costs
Cost of sales									0	0	0
Construction services									0	0	0
Sales and marketing									0	0	0
General and administrative									0	0	0
Transaction expenses										0
Amortization of intangible assets									0	0	0
Other									0	0	0
Operating costs									0	0	0
(Loss) income from subsidiaries									57,336	44,625	129,132
Operating income									57,336	44,625	129,132
Equity in income of unconsolidated joint ventures									0	0
Interest expense, net of amounts capitalized											0
Other income (expense), net									0	0	0
(Loss) income before reorganization items and provision for income taxes											129,132
Reorganization items, net											0
(Loss) income before provision for income taxes									57,336	44,625	129,132
Benefit (provision) for income taxes									0	0	0
Net income									57,336	44,625	129,132
Less: Net income attributable to noncontrolling interests									0	0	0
Net income attributable to William Lyon Homes											129,132
Preferred stock dividends											(1,528)
Net income available to common stockholders									57,336	44,625	127,604
California Lyon
Operating revenue
Sales									462,490	524,990	310,919
Construction services									25,124	37,728	32,533
Management fees									(1,506)	(2,926)	1,351
Operating revenue									486,108	559,792	344,803
Operating costs
Cost of sales									(360,522)	(400,712)	(236,165)
Construction services									(21,181)	(30,700)	(25,598)
Sales and marketing									(26,626)	(27,418)	(15,615)
General and administrative									(47,385)	(47,353)	(37,031)
Transaction expenses										(5,832)
Amortization of intangible assets									(957)	(1,814)	(1,854)
Other									(3,477)	(3,685)	(2,163)
Operating costs									(460,148)	(517,514)	(318,426)
(Loss) income from subsidiaries									(2,395)	11,575	21,889
Operating income									23,565	53,853	48,266
Equity in income of unconsolidated joint ventures									1,912	0
Interest expense, net of amounts capitalized											(2,476)
Other income (expense), net									7,140	2,883	1,745
(Loss) income before reorganization items and provision for income taxes											47,535
Reorganization items, net											(464)
(Loss) income before provision for income taxes									32,617	56,736	47,071
Benefit (provision) for income taxes									(26,806)	(23,797)	82,315
Net income									5,811	32,939	129,386
Less: Net income attributable to noncontrolling interests									0	0	0
Net income attributable to William Lyon Homes											129,386
Preferred stock dividends											0
Net income available to common stockholders									5,811	32,939	129,386
Guarantor Subsidiaries
Operating revenue
Sales									568,774	236,245	180,673
Construction services									0	0	0
Management fees									0	0	0
Operating revenue									568,774	236,245	180,673
Operating costs
Cost of sales									(475,043)	(196,773)	(150,450)
Construction services									0	0	0
Sales and marketing									(31,231)	(14,186)	(8,908)
General and administrative									(11,776)	(7,271)	(3,720)
Transaction expenses										0
Amortization of intangible assets									0	0	0
Other									1,505	825	(3)
Operating costs									(516,545)	(217,405)	(163,081)
(Loss) income from subsidiaries									0	0	0
Operating income									52,229	18,840	17,592
Equity in income of unconsolidated joint ventures									1,327	555
Interest expense, net of amounts capitalized											(126)
Other income (expense), net									4,793	(23)	(147)
(Loss) income before reorganization items and provision for income taxes											17,319
Reorganization items, net											0
(Loss) income before provision for income taxes									58,349	19,372	17,319
Benefit (provision) for income taxes									0	0	(13)
Net income									58,349	19,372	17,306
Less: Net income attributable to noncontrolling interests									0	0	0
Net income attributable to William Lyon Homes											17,306
Preferred stock dividends											0
Net income available to common stockholders									58,349	19,372	17,306
Non-Guarantor Subsidiaries
Operating revenue
Sales									50,164	97,716	48,410
Construction services									0	0	0
Management fees									0	0	0
Operating revenue									50,164	97,716	48,410
Operating costs
Cost of sales									(43,653)	(78,649)	(34,924)
Construction services									0	0	0
Sales and marketing									(3,682)	(4,299)	(1,579)
General and administrative									0	(2)	(19)
Transaction expenses										0
Amortization of intangible assets									0	0	0
Other									0	(14)	0
Operating costs									(47,335)	(82,964)	(36,522)
(Loss) income from subsidiaries									0	0	0
Operating income									2,829	14,752	11,888
Equity in income of unconsolidated joint ventures									0	0
Interest expense, net of amounts capitalized											0
Other income (expense), net									(9,123)	(962)	(1,088)
(Loss) income before reorganization items and provision for income taxes											10,800
Reorganization items, net											0
(Loss) income before provision for income taxes									(6,294)	13,790	10,800
Benefit (provision) for income taxes									0	0	0
Net income									(6,294)	13,790	10,800
Less: Net income attributable to noncontrolling interests									(2,925)	(9,901)	(6,471)
Net income attributable to William Lyon Homes											4,329
Preferred stock dividends											0
Net income available to common stockholders									(9,219)	3,889	4,329
Eliminating Entries
Operating revenue
Sales									0	0	0
Construction services									0	0	0
Management fees									1,506	2,926	(1,351)
Operating revenue									1,506	2,926	(1,351)
Operating costs
Cost of sales									(1,506)	(2,926)	1,351
Construction services									0	0	0
Sales and marketing									0	0	0
General and administrative									0	0	0
Transaction expenses										0
Amortization of intangible assets									0	0	0
Other									0	0	0
Operating costs									(1,506)	(2,926)	1,351
(Loss) income from subsidiaries									(54,941)	(56,200)	(151,021)
Operating income									(54,941)	(56,200)	(151,021)
Equity in income of unconsolidated joint ventures									0	0
Interest expense, net of amounts capitalized											0
Other income (expense), net									0	0	0
(Loss) income before reorganization items and provision for income taxes											(151,021)
Reorganization items, net											0
(Loss) income before provision for income taxes									(54,941)	(56,200)	(151,021)
Benefit (provision) for income taxes									0	0	0
Net income									(54,941)	(56,200)	(151,021)
Less: Net income attributable to noncontrolling interests									0	0	0
Net income attributable to William Lyon Homes											(151,021)
Preferred stock dividends											0
Net income available to common stockholders									$ (54,941)	$ (56,200)	$ (151,021)