Subsequent Events - Additional Information (Detail) (USD $)	12 Months Ended			12 Months Ended	0 Months Ended			0 Months Ended			12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 Interest rate cap	Dec. 31, 2013 Restricted Stock Awards	Mar. 14, 2014 Subsequent Event Interest rate cap	Mar. 03, 2014 Subsequent Event Restricted Stock Awards	Feb. 28, 2014 Subsequent Event Construction Loans Oceaneering International Facility	Jan. 17, 2014 Subsequent Event Liberty Apartments	Jan. 09, 2014 Subsequent Event Dividend Paid	Feb. 18, 2014 Subsequent Event Dividend Declared	Dec. 31, 2013 Subsequent Event Dividend Declared
Subsequent Event [Line Items]
Dividends paid	$ 7,733,000								$ 5,200,000
Acquisition, total consideration								30,700,000
Acquisition, common units issued								695,652
Acquisition, repayment of loan								3,000,000
Acquisition, assumption of debt								20,900,000
Cash dividend/distribution, date declared											Feb. 18, 2014
Cash dividend/distribution per share, declared	$ 0.40									$ 0.16
Development and construction loan							19,500,000
Restricted stock granted				169,227		99,289
Restricted stock granted, grant date fair value				$ 11.50		$ 9.94
Interest rate cap agreement, notional amount	$ 131,377,000	$ 21,077,000	$ 121,500,000		$ 50,000,000
Interest rate cap agreement, strike price					1.25%
Interest rate cap agreement, expiration date					Mar. 01, 2017