Segment Information Segment Information (Land-Related Charges by Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Restructuring Cost and Reserve [Line Items]
Land-related charges	$ 2,146	$ 2,662	$ 131,254	$ 13,185
Northeast
Restructuring Cost and Reserve [Line Items]
Land-related charges	1,184	464	51,102	990
Southeast
Restructuring Cost and Reserve [Line Items]
Land-related charges	889	396	1,847	2,252
Florida
Restructuring Cost and Reserve [Line Items]
Land-related charges	109	68	8,862	597
Midwest
Restructuring Cost and Reserve [Line Items]
Land-related charges	(393)	391	7,703	1,242
Texas
Restructuring Cost and Reserve [Line Items]
Land-related charges	51	245	898	397
West
Restructuring Cost and Reserve [Line Items]
Land-related charges	306	1,098	56,747	7,707
Other homebuilding
Restructuring Cost and Reserve [Line Items]
Land-related charges	$ 0	$ 0	$ 4,095	$ 0