Schedule III - Changes in Accumulated Depreciation (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Abstract]
Balance at beginning of period	$ 181,441	$ 144,235	$ 114,399
Depreciation	60,796	46,935	33,349
Depreciation on disposed property	(8,887)	(9,213)	(3,513)
Other	(675)	(516)
Balance at end of period	$ 232,675	$ 181,441	$ 144,235