Indebtedness - Additional Information (Detail) (USD $)			0 Months Ended	6 Months Ended			6 Months Ended			0 Months Ended		6 Months Ended	0 Months Ended
	Jun. 30, 2014	Dec. 31, 2013	Jan. 17, 2014 Liberty Apartments [Member]	Jun. 30, 2014 Liberty Apartments [Member]	Jun. 13, 2014 Liberty Apartments [Member]	Jan. 17, 2014 Liberty Apartments [Member]	Jun. 30, 2014 Construction Loans [Member]	Jun. 30, 2014 Construction Loans [Member] Oceaneering international Facility [Member]	Feb. 28, 2014 Construction Loans [Member] Oceaneering international Facility [Member]	Feb. 28, 2014 Construction Loans [Member] Oceaneering international Facility [Member] LIBOR [Member]	Apr. 22, 2014 Operating Partnership [Member]	Jun. 30, 2014 Operating Partnership [Member]	Jul. 14, 2014 Operating Partnership [Member] Subsequent Event [Member]
Debt Instrument [Line Items]
Acquisition, assumption of debt			$ 17,000,000
Fair value adjustment of debt of liberty apartment			1,500,000
Outstanding principal amount of debt				16,966,000		18,500,000
Loans available under Liberty Apartments loan					2,400,000
Debt assumed, interest rate						5.66%
Stated maturity date				Nov. 01, 2043				Feb. 28, 2018
Debt assumed, term			30 years
Debt, face value									19,500,000
Stated interest rate, basis spread on variable rate										1.75%
Indebtedness	349,840,000	277,745,000					3,400,000
Effective interest rate percentage							1.90%
Financial covenant, maximum leverage ratio as of the last day of each fiscal quarter											65.00%
Revolving credit facility, borrowed amount							32,900,000					18,000,000	5,000,000
Revolving credit facility, outstanding amount												$ 88,000,000