Segment Disclosures - Additional Information (Detail)	3 Months Ended
Mar. 31, 2018 segment
Senior Notes due 2022 [Member]
Segment Reporting Information [Line Items]
Senior notes interest rate	3.95%
Senior notes maturity	Sep. 15, 2022
Homebuilding [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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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