Indebtedness - Additional Information (Detail) (USD $)			0 Months Ended		3 Months Ended		0 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Jan. 17, 2014 Liberty Apartments [Member]	Mar. 31, 2014 Liberty Apartments [Member]	Mar. 31, 2014 Operating Partnership [Member]	Mar. 31, 2014 Construction Loans [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 Subsequent Event [Member] Operating Partnership [Member]	Apr. 14, 2014 Subsequent Event [Member] Operating Partnership [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			18,500,000	16,966,000
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	317,271,000	277,745,000				0
Revolving credit facility, borrowed amount					10,000,000	13,300,000				8,000,000
Revolving credit facility, outstanding amount					$ 80,000,000
Financial covenant, maximum leverage ratio as of the last day of each fiscal quarter									65.00%