Real Estate Held for Investment (Detail) (USD $)	9 Months Ended	0 Months Ended	12 Months Ended			0 Months Ended	12 Months Ended	9 Months Ended
	Sep. 30, 2012	Feb. 23, 2012 Tractor Supply Starkville MS	Feb. 23, 2013 Tractor Supply Starkville MS	Jul. 23, 2012 Family Dollar Mobile AL Leases, Acquired-in-Place [Member]	Jul. 23, 2012 Family Dollar Mobile AL Above Market Leases [Member]	Jul. 23, 2012 Family Dollar Mobile AL	Jul. 23, 2013 Family Dollar Mobile AL	Sep. 30, 2012 Leases, Acquired-in-Place [Member]	Sep. 30, 2011 Leases, Acquired-in-Place [Member]	Sep. 30, 2012 Above Market Leases [Member]	Sep. 30, 2011 Above Market Leases [Member]	Sep. 30, 2012 Below Market Leases [Member]	Sep. 30, 2011 Below Market Leases [Member]
Business Acquisition, Effective Date of Acquisition		Feb. 23, 2012				Jul. 23, 2012
Business Acquisition, Percentage of Voting Interests Acquired		47.00%
Business Acquisition, Name of Acquired Entity		Tractor Supply Company store in Starkville, Mississippi				Family Dollar store in Mobile, Alabama
Business Acquisition, Cost of Acquired Entity, Cash Paid		$ 1,339,500				$ 1,410,900
Business Acquisition, Purchase Price Allocation, Amortizable Intangible Assets		228,586		190,845	284,566	475,411
Business Acquisition, Purchase Price Allocation, Noncurrent Liabilities		82,065
Business Acquisition, Cost of Acquired Entity, Transaction Costs		23,079				28,263
Average Lease Term		15				9.9
Other Real Estate Revenue			102,462				119,926
Amortization of Acquired Intangible Assets								12,147	0
Amortization of above and below Market Leases										4,783	0	3,209	0
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	130 months
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months								$ 34,569		$ 28,696		$ 5,502