Consolidated and Combined Results of Operations on a Pro Forma Basis (Detail) (USD $) In Thousands, unless otherwise specified	1 Months Ended	3 Months Ended		9 Months Ended
	May 13, 2013	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Rental revenues	$ 2,300	$ 14,899	$ 14,767	$ 44,538	$ 44,564
Net (loss) income	$ (300)	$ 1,448	$ 1,863	$ 2,667	$ 15,233