Commitments and Contingencies Warranty Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended	48 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2018
Warranty Accrual Rollforward [Abstract]
Warranty reserves, beginning of period	$ 26,420	$ 26,459	$ 26,133
Warranty expense on homes delivered during the period	17,913	14,685	13,456
Changes in estimates for pre-existing warranties	1,315	2,165	4,746
Charges related to stucco-related claims	860	0	0	$ 28,400
Standard and Extended Product Warranty Accrual, Decrease for Payments	(17,496)	(16,889)	(17,876)
Warranty reserves, end of period	29,012	26,420	26,459	$ 26,459
Insurance Recoveries	700	$ 1,100	1,000
stucco repair cost	1,600		$ 1,000
Estimated Repair Costs for Affected Homes	$ 4,700

Estimated Repair Costs for Affected Homes

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stucco repair cost

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Warranty Accrual Rollforward [Abstract]

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No definition available.

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The amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section S99
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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

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-Publisher FASB
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Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

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Amount of increase (decrease) in the standard and extended product warranty liability.

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Amount of increase (decrease) in the standard and extended product warranty accrual from changes in estimates attributable to preexisting product warranties.

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Amount of increase in the standard and extended product warranty accrual from warranties issued.

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