Summary of Quarterly Financial Data (Tables)

12 Months Ended

Dec. 31, 2012

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Financial Information [Table Text Block]

The following table sets forth selected Quarterly Financial Data for the Company on a historical basis for each of the years ended December 31, 2012 and 2011 and has been derived from the accompanying consolidated financial statements as reclassified for discontinued operations (in thousands except per share and per unit data):

2012:		First		Second		Third		Fourth
		Quarter		Quarter		Quarter		Quarter
Operating Data:
Revenues as originally reported	$	127,389		129,767		120,013		122,002
Reclassified to discontinued operations		(1,146	)	(524	)	(581	)	—
Adjusted Revenues	$	126,243		129,243		119,432		122,002
Net income (loss) attributable to common stockholders	$	13,181		5,697		11,637		(37,179	)
Net income (loss) of limited partners		54		23		39		(10	)
Net income (loss) attributable to common unit holders	$	13,235		5,720		11,676		(37,189	)
Net income (loss) attributable to common stock and unit holders per share and unit:
Basic	$	0.14		0.06		0.13		(0.41	)
Diluted	$	0.14		0.06		0.13		(0.41	)
2011:
Operating Data:
Revenues as originally reported	$	127,114		128,382		125,747		125,322
Reclassified to discontinued operations		(4,069	)	(4,344	)	(3,328	)	(1,726	)
Adjusted Revenues	$	123,045		124,038		122,419		123,596
Net income attributable to common stockholders	$	2,185		12,861		8,510		8,139
Net income of limited partners		13		37		27		26
Net income attributable to common unit holders	$	2,198		12,898		8,537		8,165
Net income attributable to common stock and unit holders per share and unit:
Basic	$	0.02		0.14		0.09		0.10
Diluted	$	0.02		0.14		0.09		0.10