Commitments and Contingencies Warranty Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Jun. 30, 2017	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Warranty Accrual Rollforward [Abstract]
Warranty reserves, beginning of period				$ 14,282	$ 27,732	$ 14,282	$ 12,671
Warranty expense on homes delivered during the period					11,677	10,452	8,812
Changes in estimates for pre-existing warranties					2,614	3,304	5,160
Charges related to stucco-related claims (a)	$ 8,500	$ 14,500	$ 2,800	$ 2,200	8,500	19,409	0
Settlements made during the period					(24,390)	(19,715)	(12,361)
Warranty reserves, end of period					$ 26,133	$ 27,732	$ 14,282

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://www.xbrl.org/2003/role/presentationRef
-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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(5)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-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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- 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

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

+ References

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- Definition

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

+ References

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- Definition

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

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