Senior Notes, Secured, and Subordinated Indebtedness - Consolidating Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
ASSETS
Cash and cash equivalents	$ 50,203	$ 52,771	$ 171,672	$ 71,075
Restricted cash	504	504
Receivables	14,838	21,250
Escrow proceeds receivable	3,041	2,915
Real estate inventories	1,675,106	1,404,639
Investment in unconsolidated joint ventures	5,413	2,500
Goodwill	66,902	60,887
Intangibles, net of accumulated amortization of $4,640 and $3,683 and as of December 31, 2015 and 2014, respectively	6,700	7,657
Deferred income taxes, net	79,726	88,039
Other assets, net	21,017	18,562
Investments in subsidiaries	0	0
Intercompany receivables	0	0
Total assets	1,923,450	1,659,724
LIABILITIES AND EQUITY
Accounts payable	75,881	51,814
Accrued expenses	70,324	85,366
Notes payable	175,181	39,235
Long-term debt, gross	1,105,776	925,398
Intercompany payables	0	0
Total liabilities	1,251,981	1,062,578
Equity
William Lyon Homes stockholders’ equity	632,095	569,915
Noncontrolling interests	39,374	27,231
Total liabilities and equity	1,923,450	1,659,724
Delaware Lyon
ASSETS
Cash and cash equivalents	0	0	0	0
Restricted cash	0	0
Receivables	0	0
Escrow proceeds receivable	0	0
Real estate inventories	0	0
Investment in unconsolidated joint ventures	0	0
Goodwill	0	0
Intangibles, net of accumulated amortization of $4,640 and $3,683 and as of December 31, 2015 and 2014, respectively	0	0
Deferred income taxes, net	0	0
Other assets, net	0	0
Investments in subsidiaries	632,095	569,915
Intercompany receivables	0	0
Total assets	632,095	569,915
LIABILITIES AND EQUITY
Accounts payable	0	0
Accrued expenses	0	0
Notes payable	0	0
Intercompany payables	0	0
Total liabilities	0	0
Equity
William Lyon Homes stockholders’ equity	632,095	569,915
Noncontrolling interests	0	0
Total liabilities and equity	632,095	569,915
California Lyon
ASSETS
Cash and cash equivalents	44,331	48,462	166,516	69,376
Restricted cash	504	504
Receivables	8,986	16,783
Escrow proceeds receivable	2,020	613
Real estate inventories	922,990	755,748
Investment in unconsolidated joint ventures	5,263	2,350
Goodwill	14,209	14,209
Intangibles, net of accumulated amortization of $4,640 and $3,683 and as of December 31, 2015 and 2014, respectively	0	957
Deferred income taxes, net	79,726	88,039
Other assets, net	18,981	16,178
Investments in subsidiaries	(34,522)	(35,961)
Intercompany receivables	0	0
Total assets	1,062,488	907,882
LIABILITIES AND EQUITY
Accounts payable	45,065	28,792
Accrued expenses	62,167	76,664
Notes payable	80,915	384
Intercompany payables	170,757	164,541
Total liabilities	1,289,499	1,156,544
Equity
William Lyon Homes stockholders’ equity	(227,011)	(248,662)
Noncontrolling interests	0	0
Total liabilities and equity	1,062,488	907,882
Guarantor Subsidiaries
ASSETS
Cash and cash equivalents	2,724	573	28	65
Restricted cash	0	0
Receivables	937	878
Escrow proceeds receivable	1,021	2,302
Real estate inventories	589,762	554,170
Investment in unconsolidated joint ventures	150	150
Goodwill	52,693	46,678
Intangibles, net of accumulated amortization of $4,640 and $3,683 and as of December 31, 2015 and 2014, respectively	6,700	6,700
Deferred income taxes, net	0	0
Other assets, net	1,737	2,026
Investments in subsidiaries	(561,546)	(574,129)
Intercompany receivables	239,248	232,895
Total assets	333,426	272,243
LIABILITIES AND EQUITY
Accounts payable	27,807	19,023
Accrued expenses	8,059	8,610
Notes payable	0	162
Intercompany payables	0	0
Total liabilities	35,866	27,795
Equity
William Lyon Homes stockholders’ equity	297,560	244,448
Noncontrolling interests	0	0
Total liabilities and equity	333,426	272,243
Non-Guarantor Subsidiaries
ASSETS
Cash and cash equivalents	3,148	3,736	5,128	1,634
Restricted cash	0	0
Receivables	4,915	3,589
Escrow proceeds receivable	0	0
Real estate inventories	162,354	94,721
Investment in unconsolidated joint ventures	0	0
Goodwill	0	0
Intangibles, net of accumulated amortization of $4,640 and $3,683 and as of December 31, 2015 and 2014, respectively	0	0
Deferred income taxes, net	0	0
Other assets, net	299	358
Investments in subsidiaries	0	0
Intercompany receivables	0	0
Total assets	170,716	102,404
LIABILITIES AND EQUITY
Accounts payable	3,009	3,999
Accrued expenses	98	92
Notes payable	94,266	38,689
Intercompany payables	68,491	68,354
Total liabilities	165,864	111,134
Equity
William Lyon Homes stockholders’ equity	(34,522)	(35,961)
Noncontrolling interests	39,374	27,231
Total liabilities and equity	170,716	102,404
Eliminating Entries
ASSETS
Cash and cash equivalents	0	0	$ 0	$ 0
Restricted cash	0	0
Receivables	0	0
Escrow proceeds receivable	0	0
Real estate inventories	0	0
Investment in unconsolidated joint ventures		0
Goodwill	0	0
Intangibles, net of accumulated amortization of $4,640 and $3,683 and as of December 31, 2015 and 2014, respectively	0	0
Deferred income taxes, net	0	0
Other assets, net	0	0
Investments in subsidiaries	(36,027)	40,175
Intercompany receivables	(239,248)	(232,895)
Total assets	(275,275)	(192,720)
LIABILITIES AND EQUITY
Accounts payable	0	0
Accrued expenses	0	0
Notes payable	0	0
Intercompany payables	(239,248)	(232,895)
Total liabilities	(239,248)	(232,895)
Equity
William Lyon Homes stockholders’ equity	(36,027)	40,175
Noncontrolling interests	0	0
Total liabilities and equity	(275,275)	(192,720)
Subordinated amortizing notes
LIABILITIES AND EQUITY
Long-term debt, gross	14,066	20,717
Subordinated amortizing notes | Delaware Lyon
LIABILITIES AND EQUITY
Long-term debt, gross	0	0
Subordinated amortizing notes | California Lyon
LIABILITIES AND EQUITY
Long-term debt, gross	14,066	20,717
Subordinated amortizing notes | Guarantor Subsidiaries
LIABILITIES AND EQUITY
Long-term debt, gross	0	0
Subordinated amortizing notes | Non-Guarantor Subsidiaries
LIABILITIES AND EQUITY
Long-term debt, gross	0	0
5 3/4% Senior Notes due 2019
LIABILITIES AND EQUITY
Long-term debt, gross	148,295	147,766
5 3/4% Senior Notes due 2019 | Delaware Lyon
LIABILITIES AND EQUITY
Long-term debt, gross	0	0
5 3/4% Senior Notes due 2019 | California Lyon
LIABILITIES AND EQUITY
Long-term debt, gross	148,295	147,766
5 3/4% Senior Notes due 2019 | Guarantor Subsidiaries
LIABILITIES AND EQUITY
Long-term debt, gross	0	0
5 3/4% Senior Notes due 2019 | Non-Guarantor Subsidiaries
LIABILITIES AND EQUITY
Long-term debt, gross	0	0
8 1/2% Senior Notes due 2020
LIABILITIES AND EQUITY
Long-term debt, gross	422,896	422,889
8 1/2% Senior Notes due 2020 | Delaware Lyon
LIABILITIES AND EQUITY
Long-term debt, gross	0	0
8 1/2% Senior Notes due 2020 | California Lyon
LIABILITIES AND EQUITY
Long-term debt, gross	422,896	422,889
8 1/2% Senior Notes due 2020 | Guarantor Subsidiaries
LIABILITIES AND EQUITY
Long-term debt, gross	0	0
8 1/2% Senior Notes due 2020 | Non-Guarantor Subsidiaries
LIABILITIES AND EQUITY
Long-term debt, gross	0	0
8 1/2% Senior Notes due 2020 | Eliminating Entries
LIABILITIES AND EQUITY
Long-term debt, gross	0	0
7% Senior Notes due 2022
LIABILITIES AND EQUITY
Long-term debt, gross	345,338	294,791
7% Senior Notes due 2022 | Delaware Lyon
LIABILITIES AND EQUITY
Long-term debt, gross	0	0
7% Senior Notes due 2022 | California Lyon
LIABILITIES AND EQUITY
Long-term debt, gross	345,338	294,791
7% Senior Notes due 2022 | Guarantor Subsidiaries
LIABILITIES AND EQUITY
Long-term debt, gross	0	0
7% Senior Notes due 2022 | Non-Guarantor Subsidiaries
LIABILITIES AND EQUITY
Long-term debt, gross	$ 0	$ 0