Joint Ventures - Condensed Balance Sheets (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Assets:
Cash	$ 364,494	$ 425,316	$ 497,585	$ 545,419
Land under development	58,751
Liabilities and equity:
Equity	1,357,601	1,239,165
Total liabilities and shareholders' equity	2,698,424	2,511,718
Consolidated Joint Venture
Assets:
Cash	1,292	990
Other assets	19	379
Land under development		380
Total assets	1,311	1,749
Liabilities and equity:
Accrued expenses	622	567
Equity	689	1,182
Total liabilities and shareholders' equity	$ 1,311	$ 1,749