Commitments and Contingencies (Details Textual) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2012 Partner Venture	May 31, 2012	Jan. 31, 2012
Commitments and Contingencies (Additional Textual) [Abstract]
Sales price of management rights and intellectual property		$ 210
Number of joint ventures	2
Real Estate funds serving as joint venture partners	2
Ownership in joint venture			50.00%
Estimated amount of investment under project			50
One Time Costs Related to REIT Conversion	55
Federal Income Taxes Associated With Transaction Minimum	43
Federal Income Taxes Associated With Transaction Maximum	53
Corporate Joint Venture [Member]
Commitments and contingencies (Textual) [Abstract]
Maximum potential amount liable under contribution agreement	16.9
Total debt subject to guarantees	$ 86.4