Land Under Development - Additional Information (Detail) $ in Thousands	1 Months Ended	12 Months Ended
Oct. 31, 2017 USD ($) lot	Dec. 31, 2017 USD ($) lot parcel	Dec. 31, 2016 USD ($) lot parcel
Real Estate [Abstract]
Acquisition costs of land under development and finished lots	$ 14,800
Number of finished lots for use in homebuilding operations \| lot	150	500	600
Number of raw parcels of land owned \| parcel		4	4
Carrying value of raw parcels of land		$ 34,212	$ 46,999
Aggregate additional funding commitments related to raw land property under joint development		7,900
Expected development credits that will offset the aggregate additional funding commitments related to raw land property development		$ 4,700

Aggregate additional funding commitments related to raw land property development.

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- Definition

Expected development credit offset amount.

+ References

No definition available.

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- Definition

Number of finished lots intended to be developed from raw parcels of land for use in homebuilding operation.

+ References

No definition available.

+ Details

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- Definition

Number of raw parcels of land owned.

+ References

No definition available.

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- Definition

Carrying amount as of the balance sheet date, net of valuation allowances and impairment losses, of costs of land expected to be developed in the near term plus capitalized costs of development, for purposes of selling completed units to home buyers or commercial or industrial entities..

+ 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 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The cash outflow for acquisition of land for use; excludes purchases of land held as inventory or as investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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- References

No definition available.

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