Selected Quarterly Financial Data (Unaudited) (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Total revenues	$ 198,419	$ 198,283	$ 246,181	$ 242,653	$ 231,957	$ 222,632	$ 217,346	$ 209,970	$ 885,536	$ 881,905	$ 741,344
Previously reported
Total revenues		201,741	274,766	275,048	264,692	255,225	249,797	243,378
Revenues from properties reclassified (to) from discontinued operations		$ (3,458)	$ (28,585)	$ (32,395)	$ (32,735)	$ (32,593)	$ (32,451)	$ (33,408)