Fair Value of Financial Instruments - Summary of Fair Value Information of Financial Instruments (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Interest and rent receivables, Book value	$ 68,537	$ 57,698
Loans, Book value	984,784	986,987
Debt, net Book value	(3,221,054)	(2,909,341)
Interest and rent receivables, Fair value	68,698	57,707
Loans, Fair value	1,009,687	1,017,428
Debt, net Fair value	$ (3,384,541)	$ (2,966,759)