Equity - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended	3 Months Ended		6 Months Ended			0 Months Ended								6 Months Ended	0 Months Ended
	Mar. 31, 2014	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013	Aug. 01, 2014 Subsequent Event [Member]	Apr. 10, 2014 Dividend Paid [Member] Common Stockholders [Member]	Jan. 09, 2014 Dividend Paid [Member] Common Stockholders [Member]	Jul. 10, 2014 Dividend Paid [Member] Common Stockholders [Member] Subsequent Event [Member]	Apr. 10, 2014 Dividend Paid [Member] Common Unitholders [Member]	Jan. 09, 2014 Dividend Paid [Member] Common Unitholders [Member]	Jul. 10, 2014 Dividend Paid [Member] Common Unitholders [Member] Subsequent Event [Member]	May 09, 2014 Dividend Declared [Member]	Jun. 30, 2014 Dividend Declared [Member]	Aug. 04, 2014 Dividend Declared [Member] Subsequent Event [Member]	Jan. 17, 2014 Liberty Apartments [Member]
Class of Stock [Line Items]
Authorized capital shares of common stock		500,000,000		500,000,000		500,000,000
Authorized capital shares of preferred stock		100,000,000		100,000,000		100,000,000
Shares of common stock issued		19,265,919		19,265,919		19,163,413
Shares of common stock outstanding		19,265,919		19,265,919		19,163,413
Preferred stock issued		0		0		0
Preferred stock outstanding		0		0		0
Percentage of Operating Partnership held		58.30%		58.30%		59.50%
Acquisition, common units issued							990,000										695,652
Common units in exchange for all noncontrolling interests	30,000
Aggregate cash dividends and distributions, paid				$ 10,441				$ 3,100	$ 3,100	$ 3,100	$ 2,200	$ 2,100	$ 2,200
Cash dividend/distribution, date declared															May 09, 2014	Aug. 04, 2014
Cash dividend/distribution per share, declared		$ 0.16	$ 0.08	$ 0.32	$ 0.08									$ 0.16		$ 0.16
Cash dividend/distribution, date payable															Jul. 10, 2014	Oct. 09, 2014
Cash dividend/distribution, date of record															Jul. 01, 2014	Oct. 01, 2014