Commitments and Contingencies (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 Joint_Venture	Dec. 31, 2011	Dec. 31, 2010
Commitments and Contingencies (Textual) [Abstract]
Amount of settlement received in civil suit		$ 3.2
Lease income per diem arrangements recognized	2.1	2.9	2.6
Management and service fees	3.8	2.8	2.9
Rental expense under agreements net	7.3	6.3	5.6
Future minimum lease payments, 2013	3.8
Future minimum lease payments, 2014	3.2
Future minimum lease payments, 2015	2.5
Future minimum lease payments, 2016	1.3
Future minimum lease payments, 2017	0.7
Future minimum lease payments, thereafter	1.7
Number of ethanol joint ventures	2
Periods of lease income renewals	7 years 6 months
Operating lease income	$ 1.9	$ 1.9	$ 1.8