Segment Disclosures - Additional Information (Detail)	9 Months Ended
Sep. 30, 2018 segment
Senior Notes due 2022 [Member]
Segment Reporting Information [Line Items]
Senior notes interest rate	3.95%
Senior notes maturity	Sep. 15, 2022
Home Building [Member]
Segment Reporting Information [Line Items]
Number of reportable segments	4
Mortgage Banking [Member]
Segment Reporting Information [Line Items]
Number of reportable segments	1

Contractual interest rate for funds borrowed, under the debt agreement.

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-Topic 210
-SubTopic 10
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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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