Real Estate (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Pro forma financial information
Total revenue	$ 62,836	$ 56,293	$ 177,683	$ 154,276
Total operating expenses	43,716	41,137	123,980	110,222
OPERATING INCOME	19,120	15,156	53,703	44,054
Net income (loss)	4,285	4,618	9,780	18,669
As Reported [Member]
Pro forma financial information
Total revenue			177,683	154,276
Total operating expenses			123,980	110,222
OPERATING INCOME			53,703	44,054
Net income (loss)			9,993	13,569
Pro Forma [Member]
Pro forma financial information
Total revenue			186,776	179,780
Total operating expenses			134,068	133,590
OPERATING INCOME			52,708	46,190
Net income (loss)			$ 9,126	$ 31,199