Segment Reporting - Total Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Total Assets	$ 4,382,930	$ 3,864,920
Homebuilding:
Segment Reporting Information [Line Items]
Total Assets	4,000,100	3,506,420
Financial Services:
Segment Reporting Information [Line Items]
Total Assets	382,830	358,500
Operating Segments | Homebuilding: | West
Segment Reporting Information [Line Items]
Total Assets	1,968,336	1,855,567
Operating Segments | Homebuilding: | Mountain
Segment Reporting Information [Line Items]
Total Assets	983,488	905,007
Operating Segments | Homebuilding: | East
Segment Reporting Information [Line Items]
Total Assets	309,571	274,937
Operating Segments | Financial Services: | Mortgage operations
Segment Reporting Information [Line Items]
Total Assets	297,801	279,649
Operating Segments | Financial Services: | Other
Segment Reporting Information [Line Items]
Total Assets	85,029	78,851
Corporate | Homebuilding:
Segment Reporting Information [Line Items]
Total Assets	$ 738,705	$ 470,909