Commitments and Contingencies (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Jun. 30, 2011
Commitments and Contingencies (Textual) [Abstract]
Amount of settlement received in civil suit				$ 3.2
Management and service fees	2.8	2.9	3.0
Lease income per diem arrangements recognized	2.9	2.6	3.9
Future minimum lease payments, 2012	4.2
Future minimum lease payments, 2013	3.0
Future minimum lease payments, 2014	1.8
Future minimum lease payments, 2015	1.3
Future minimum lease payments, 2016	0.4
Future minimum lease payments, thereafter	1.4
Rental expense under agreements net	6.3	5.6	5.1
Number of operating leases	2
Number of renewals	5
Periods of lease income renewals	7 years 6 months
Operating lease income	$ 1.9	$ 1.8	$ 1.8