Joint Ventures - Condensed Balance Sheets of Consolidated JV (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Assets:
Cash	$ 497,585	$ 545,419	$ 553,705	$ 866,253
Land under development	25,554
Liabilities and equity:
Equity	1,274,881	1,124,255
Total liabilities and shareholders' equity	2,596,235	2,351,335
Consolidated Joint Venture
Assets:
Cash	1,854	481
Restricted cash		160
Other assets	199	332
Land under development	849	2,617
Total assets	2,902	3,590
Liabilities and equity:
Debt		64
Accrued expenses	1,389	1,231
Equity	1,513	2,295
Total liabilities and shareholders' equity	$ 2,902	$ 3,590