Commitments and Contingencies (Details Textual) $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($) Joint_Venture	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Lease income per diem arrangements recognized	$ 5.0	$ 3.4	$ 2.0
Management and service fees	7.0	8.4	7.9
Rental expense under agreements net	10.9	8.9	8.4
Future minimum lease payments, 2016	3.5
Future minimum lease payments, 2017	1.9
Future minimum lease payments, 2018	1.1
Future minimum lease payments, 2019	0.5
Future minimum lease payments, 2020	0.1
Future minimum lease payments, thereafter	$ 0.0
Number of ethanol joint ventures | Joint_Venture	2
Periods of lease income renewals	7 years 6 months
Operating lease income	$ 2.0	$ 2.0	$ 1.9