Schedule III - Changes in Accumulated Depreciation Including Real Estate Assets Held for Sale (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Real Estate And Accumulated Depreciation Disclosure [Abstract]
Balance at beginning of period	$ 110,888	[1]	$ 93,430	[2]	$ 68,662
Depreciation	33,349		31,026		29,523
Depreciation on disposed property	(3,513)		(10,057)		(4,755)
Balance at end of period	$ 144,235		$ 110,888	[1]	$ 93,430	[2]

[1] Includes in accumulated depreciation in real estate held for sale of $3,511 for 2012. Excludes accumulated amortization related to intangible lease assets that are included in real estate held for sale of $426 for 2012.

[2] Includes accumulated depreciation in real estate held for sale of $11,807 for 2011. Excludes accumulated amortization related to intangible lease assets that are included in real estate held for sale of $1,949 for 2011.