Commitments and Contingencies Warranty Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended	48 Months Ended
Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018
Warranty Accrual Rollforward [Abstract]
Warranty reserves, beginning of period		$ 26,459	$ 26,133	$ 27,732
Warranty expense on homes delivered during the period		14,685	13,456	11,677
Changes in estimates for pre-existing warranties		2,165	4,746	2,614
Charges related to stucco-related claims	$ 1,000	0	0	8,500	$ 28,400
Settlements made during the period		(16,889)	(17,876)	(24,390)
Warranty reserves, end of period	$ 26,459	$ 26,420	$ 26,459	$ 26,133	$ 26,459

Warranty Accrual Rollforward [Abstract]

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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-SubTopic 10
-Section 50
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-Subparagraph (c)(5)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
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Amount of increase (decrease) in the standard and extended product warranty liability.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
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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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-Publisher FASB
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Amount of increase in the standard and extended product warranty accrual from warranties issued.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
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