Real Estate Investments - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended			0 Months Ended	12 Months Ended			0 Months Ended	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Aug. 01, 2014 Subsequent Event [Member]	Dec. 31, 2014 Scenario, Forecast [Member]	Apr. 16, 2014 Williamsburg Va [Member]	May 01, 2014 Chesapeake VA [Member]	Jan. 17, 2014 Liberty Apartments [Member]	Jun. 30, 2014 Liberty Apartments [Member]	Jan. 17, 2014 Liberty Apartments [Member]
Real Estate Properties [Line Items]
Acquisition, total consideration										$ 26,700,000
Acquisition, common units issued						990,000				695,652
Acquisition, assumption of debt										17,000,000
Acquisition, cash consideration						10,000,000				3,000,000
Fair value adjustment to the assumed debt										1,500,000
Outstanding principal balance of the assumed debt											16,966,000	18,500,000
Rental revenues	15,319,000	14,231,000	30,512,000	27,629,000							300,000
Net income (loss)	1,325,000	4,886,000	2,790,000	4,886,000							(1,200,000)
Land purchased	52,811,000		52,811,000		41,313,000			7,600,000	300,000
Acquisition agreement date						Aug. 01, 2014
Sale of Virginia Natural Gas office property							$ 8,900,000