The Company (Details)	Dec. 31, 2012 states properties	Dec. 31, 2011 properties states
The Company [Abstract]
Number of Consolidated Properties	220	185
Number of States in which Entity has Interests	41	39

The number of states the entity operates in as of the balance sheet date.

No definition available.

Name:	us-gaap_NumberOfStatesInWhichEntityOperates
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant