Schedule III - Real Estate and Accumulated Depreciation and Amortization - Additional Information (Detail) (USD $)	Dec. 31, 2012
Schedule Of Investments In Real Estate [Line Items]
Properties net value	$ 158,608,000
Security for senior secured revolving credit agreement	100,000,000
Jp Morgan Chase Bank [Member]
Schedule Of Investments In Real Estate [Line Items]
Security for senior secured revolving credit agreement	$ 175,000,000

Amount borrowed under the credit facility as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

Name:	us-gaap_LineOfCreditFacilityAmountOutstanding
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant