Investments - Summary of Operating Results and Financial Position (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Operating results:
Operating expenses	$ 44,180	$ 33,048	$ 123,888	$ 94,615
Net loss			(22)	0
Balance Sheet:
Other liabilities	13,343		13,343		6,772
Total liabilities and stockholders' equity	595,624		595,624		526,316
Investment in joint venture, at equity	4,478		4,478		0
Variable Interest Entity, Not Primary Beneficiary [Member]
Operating results:
Revenue	0
Operating expenses	25		25
Net loss	(25)		(25)
Balance Sheet:
Construction in progress-real estate	3,220		3,220
Cash	1,880		1,880
Total assets	5,100		5,100
Other liabilities	125		125
Members' capital	4,975		4,975
Total liabilities and stockholders' equity	5,100		5,100
Melbourne FMA [Member] | Operating Expense [Member]
Operating results:
Net loss	$ 22		$ 22