Revenue Recognition (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Revenue recognition
Adjustments necessary to record rent on straight line basis	$ (60)	$ 1,201	$ 294	$ 2,418
Deferred percentage rent	$ 1,253	$ 395	$ 2,562	$ 936