Segment Disclosures - Additional Information (Detail) - segment	9 Months Ended
Sep. 30, 2020	Sep. 10, 2012
Senior Notes due 2022 [Member]
Segment Reporting Information [Line Items]
Senior notes interest rate	3.95%	3.95%
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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
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+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599

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