CONDENSED CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
CONDENSED CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME
Rental income	$ 56,401	$ 52,426	$ 168,639	$ 149,071
Expenses:
Real estate taxes	6,255	5,498	19,060	16,520
Utility expenses	5,355	4,801	13,064	12,035
Other operating expenses	10,169	9,171	29,288	26,667
Depreciation and amortization	14,032	12,537	40,960	35,642
Acquisition related costs	1,562	763	1,701	1,057
General and administrative	2,941	3,529	9,350	9,071
Total expenses	40,314	36,299	113,423	100,992
Operating income	16,087	16,127	55,216	48,079
Interest and other income	10	7	20	21
Interest expense (including net amortization of debt premiums and deferred financing fees of $339, $339, $1,002 and $998, respectively)	(4,176)	(4,530)	(12,388)	(12,649)
Equity in earnings of an investee	64	115	219	236
Income from continuing operations before income tax benefit (expense)	11,985	11,719	43,067	35,687
Income tax benefit (expense)	36	(30)	(50)	(119)
Income from continuing operations	12,021	11,689	43,017	35,568
Income (loss) from discontinued operations	(10,055)	67	(1,121)	1,201
Net income	1,966	11,756	41,896	36,769
Other comprehensive income (loss):
Equity in unrealized loss of an investee	14	35	(67)	31
Other comprehensive income (loss)	14	35	(67)	31
Comprehensive income	$ 1,980	$ 11,791	$ 41,829	$ 36,800
Weighted average common shares outstanding (in shares)	54,684	47,108	54,666	47,086
Per common share amounts:
Income from continuing operations (in dollars per share)	$ 0.22	$ 0.25	$ 0.79	$ 0.76
Income (loss) from discontinued operations (in dollars per share)	$ (0.18)		$ (0.02)	$ 0.03
Net income (in dollars per share)	$ 0.04	$ 0.25	$ 0.77	$ 0.78