Commitments and Contingencies Warranty Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	36 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Warranty Accrual Rollforward [Abstract]
Warranty reserves, beginning of period	$ 24,301	$ 24,980	$ 26,133	$ 27,732
Warranty expense on homes delivered during the period	3,299	2,783	5,842	5,212
Changes in estimates for pre-existing warranties	557	332	465	1,062
Settlements made during the period	(4,878)	(6,292)	(9,161)	(12,203)
Warranty reserves, end of period	23,279	30,303	23,279	30,303	$ 26,133
Charges related to stucco-related claims	0	$ 8,500	0	$ 8,500	$ 28,400
Estimated Repair Costs for Affected Homes	$ 6,500		$ 6,500

Estimated Repair Costs for Affected Homes

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- Definition

Warranty Accrual Rollforward [Abstract]

+ References

No definition available.

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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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-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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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.

+ 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.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
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