Commitments and Contingencies Warranty Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Warranty Accrual Rollforward [Abstract]
Warranty reserves, beginning of period	$ 29,880	$ 26,175	$ 29,012	$ 26,420
Warranty expense on homes delivered during the period	4,834	4,961	15,246	12,624
Changes in estimates for pre-existing warranties	1,745	416	2,356	(228)
Charges related to stucco-related claims	0	0	0	0
Settlements made during the period	(6,078)	(4,578)	(16,233)	(11,842)
Warranty reserves, end of period	30,381	$ 26,974	30,381	$ 26,974
Estimated Repair Costs for Affected Homes	$ 3,200		$ 3,200