Consolidated Statements of Operations (Parenthetical) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Parent Company [Member]
Interest income	$ 587	$ 640	$ 1,188	$ 1,315
Partnership Interest [Member]
Interest income	$ 587	$ 640	$ 1,188	$ 1,315

Interest generated from day to day operating activities of the business. This element represents a revenue generating activity and is therefore gross (before any related cost of revenue items).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

Name:	us-gaap_InterestIncomeOperating
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration