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Commitments and Contingent Liabilities - Additional Information (Detail) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 USD ($) lot contract | Dec. 31, 2016 USD ($) lot | Dec. 31, 2015 USD ($)
Commitments And Contingencies [Line Items] |  |  |
Rent expense under operating leases | $ 49,400 | $ 45,800 | $ 48,100
Maximum range of deposits required under the purchase agreements | 10.00% |  |
Contingent forfeitable deposits with land developers | $ 137,900 |  |
Number of specific performance contracts | contract | 1 |  |
Finished lots committed to purchase under specific performance obligations | lot | 10 | 10 |
Purchase price of finished lots committed to purchase under specific performance obligations | $ 1,505 | $ 1,505 |
Aggregate additional funding commitments related to raw land property development | 7,900 |  |
Expected development credit offset amount | 4,700 |  |
Contingent obligations under bonds or letters of credit arrangements | 44,300 |  |
Credit Agreement |  |  |
Commitments And Contingencies [Line Items] |  |  |
Contingent obligations under letters of credit arrangements | $ 7,300 |  |

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- Definition Aggregate additional funding commitments related to raw land property development. + References No definition available. + Details
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- Definition Commitments and contingencies. + References No definition available. + Details
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- Definition Amounts represent required payments of forfeitable deposits with land developers under existing, fixed price purchase agreements, assuming that contractual development milestones are met by the developers. + References No definition available. + Details
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- Definition Contingent specific performance obligations. + References No definition available. + Details
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- Definition Expected development credit offset amount. + References No definition available. + Details
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- Definition Finished lots committed to purchase under specific performance obligations. + References No definition available. + Details
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- Definition Maximum percentage of deposits required under the purchase agreements. + References No definition available. + Details
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- Definition Number of specific performance contracts. + References No definition available. + Details
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- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717 + Details
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