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Basis of Presentation - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Contract liability, revenue recognized	$ 91,000
Cumulative-effect adjustment from adoption of ASU 2014-09, net of tax			$ 2,196
Retained Earnings [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative-effect adjustment from adoption of ASU 2014-09, net of tax			2,196
Other Assets [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Contract cost	21,500		19,500
Home Building [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Customer deposits	167,676	$ 172,033	150,033
Restricted cash and cash equivalents	19,194		19,438
Consolidated Joint Venture [Member] \| Home Building [Member] \| Other Assets [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Restricted cash and cash equivalents	$ 335		$ 1,069	$ 1,177	$ 1,214