Investments in Partnerships (Summary of Share of Equity in Income of Partnerships) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Equity Method Investments and Joint Ventures [Abstract]
Real estate revenue	$ 105,813	$ 95,643	$ 81,020
Expenses:
Operating expenses	(39,134)	(32,992)	(24,104)
Interest expense	(21,021)	(21,805)	(22,228)
Depreciation and amortization	(25,718)	(19,521)	(14,401)
Total expenses	(85,873)	(74,318)	(60,733)
Net income	19,940	21,325	20,287
Less: Partners' share	(10,128)	(10,637)	(10,096)
Company's share	9,812	10,688	10,191
Amortization of excess investment	(272)	(119)	(413)
Equity in income of partnerships	$ 9,540	$ 10,569	$ 9,778