Acquisitions, Dispositions, and Mortgage Funding (Details 4) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Revenues
Other operating	$ 1,508	$ 1,370	$ 2,965	$ 3,144
Revenues	84,054	77,593	166,477	153,597
Expenses
Property operating	31,732	29,150	61,535	57,409
General and administrative	5,841	4,520	12,382	9,781
Depreciation	22,069	20,733	43,881	41,172
Amortization	2,571	2,515	5,249	5,026
Bad debt, net of recoveries	19	150	7	109
Total Expenses	62,232	57,068	123,054	113,497
Other Income (Expense)
Loss on extinguishment of debt	(29,638)	0	(29,638)	0
Interest expense	(18,925)	(18,506)	(38,695)	(36,860)
Interest and other income, net	219	201	449	414
Total other income (expense)	(48,344)	(18,305)	(67,884)	(36,446)
Discontinued Operations
Income from discontinued operations	501	872	1,052	3,313
Impairments	0	(167)	(3,630)	(4,336)
Gain on sales of real estate properties	1,783	3	1,783	3,431
INCOME (LOSS) FROM DISCONTINUED OPERATIONS	2,284	708	(795)	2,408
Discontinued Operations [Member]
Revenues
Rental income	934	2,179	1,947	6,631
Other operating	0	5	0	10
Revenues	934	2,184	1,947	6,641
Expenses
Property operating	120	611	458	1,741
General and administrative	0	0	1	5
Depreciation	25	699	114	1,648
Amortization	(7)	(26)	18	51
Bad debt, net of recoveries	0	0	0	(1)
Total Expenses	152	1,336	591	3,444
Other Income (Expense)
Loss on extinguishment of debt	(270)	0	(270)	0
Interest expense	(17)	(25)	(41)	(49)
Interest and other income, net	6	49	7	165
Total other income (expense)	(281)	24	(304)	116
Discontinued Operations
Income from discontinued operations	501	872	1,052	3,313
Impairments	0	(167)	(3,630)	(4,336)
Gain on sales of real estate properties	1,783	3	1,783	3,431
INCOME (LOSS) FROM DISCONTINUED OPERATIONS	$ 2,284	$ 708	$ (795)	$ 2,408