Real Estate Inventories and Capitalized Interest - Interest Incurred, Capitalized, and Expensed (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Real Estate [Abstract]
Interest incurred	$ 21,978	$ 7,484	$ 4,722
Interest capitalized to inventory	(20,394)	(7,484)	(4,722)
Interest Capitalized to Investments in Unconsolidated Joint Ventures	(1,584)	0	0
Interest expense	0	0	0
Capitalized Interest [Roll Forward]
Capitalized interest in beginning inventory	6,342	4,190	2,328
Interest capitalized as a cost of inventory	20,394	7,484	4,722
Capitalized interest acquired from unconsolidated joint venture at consolidation	738	0	0
Contribution to unconsolidated joint ventures	0	(1)	(264)
Previously capitalized interest included in cost of sales	(11,021)	(5,331)	(2,511)
Interest previously capitalized as a cost of inventory, included in other expense	0	0	(85)
Capitalized interest in ending inventory	16,453	6,342	4,190
Capitalized Interest in Beginning Investments in Unconsolidated Joint Ventures	0	0	0
Interest Capitalized to Investments in Unconsolidated Joint Ventures	1,584	0	0
Capitalized interest transferred from investment in unconsolidated joint venture to inventory upon consolidation	(76)	0	0
Previously capitalized interest included in equity in net income of consolidated joint ventures	(36)	0	0
Capitalized Interest in Ending Investments in Unconsolidated Joint Ventures	1,472	0	0
Capitalized Interest in Ending Inventory and Investments in Unconsolidated Joint Ventures	$ 17,925	$ 6,342	$ 4,190
Capitalized interest as a percentage of inventory	4.00%	2.20%	2.10%
Interest included in cost of sales as a percentage of home sales revenue	2.00%	1.00%	0.90%
Capitalized interest as a percentage of investment in and advances to unconsolidated joint ventures	2.60%	0.00%	0.00%