Segment Reporting - Reconciliation of Pretax Operating Income From Segments to Consolidated (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Segment Reporting Information [Line Items]
Income before income taxes	$ 192,692	$ 126,018	$ 542,546	$ 286,218
Homebuilding:
Segment Reporting Information [Line Items]
Income before income taxes	165,152	101,650	466,168	236,240
Financial Services:
Segment Reporting Information [Line Items]
Income before income taxes	27,540	24,368	76,378	49,978
Operating Segments | Homebuilding: | West
Segment Reporting Information [Line Items]
Income before income taxes	120,284	59,120	330,390	144,441
Operating Segments | Homebuilding: | Mountain
Segment Reporting Information [Line Items]
Income before income taxes	55,386	48,053	165,296	111,372
Operating Segments | Homebuilding: | East
Segment Reporting Information [Line Items]
Income before income taxes	15,410	6,020	34,091	9,993
Operating Segments | Financial Services: | Mortgage operations
Segment Reporting Information [Line Items]
Income before income taxes	21,214	20,809	61,341	46,558
Operating Segments | Financial Services: | Other
Segment Reporting Information [Line Items]
Income before income taxes	6,326	3,559	15,037	3,420
Corporate | Homebuilding:
Segment Reporting Information [Line Items]
Income before income taxes	$ (25,928)	$ (11,543)	$ (63,609)	$ (29,566)