Joint Ventures - Condensed Balance Sheets of Consolidated JV (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Schedule Of Equity Method Investments [Line Items]
Cash	$ 532,513	$ 545,419	$ 879,323	$ 866,253
Land under development	35,813
Equity	1,165,237us-gaap_StockholdersEquity	1,124,255us-gaap_StockholdersEquity
Total liabilities and shareholders' equity	2,376,134	2,351,335
Consolidated JV [Member]
Schedule Of Equity Method Investments [Line Items]
Cash	1,545	481
Restricted cash		160
Other assets	266	332
Land under development	1,734	2,617
Total assets	3,545	3,590
Debt		64
Accrued expenses	1,399	1,231
Equity	2,146	2,295
Total liabilities and shareholders' equity	$ 3,545	$ 3,590

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities.

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