Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Segment Reporting Information [Line Items]
Revenues from external customers	$ 1,890,180	$ 2,325,041	$ 3,743,286	$ 4,301,833
Income (loss) before income taxes, net of noncontrolling interests	18,239	40,885	(20,886)	21,450
Net loss attributable to the noncontrolling interests	(10,407)	(477)	(23,856)	(632)
Income (loss) before income taxes	7,832	40,408	(44,742)	20,818
Total assets	3,303,989	3,571,859	3,303,989	3,571,859	$ 3,900,741
Operating Segments | Trade
Segment Reporting Information [Line Items]
Revenues from external customers	1,351,168	1,700,581	2,729,209	3,238,267
Income (loss) before income taxes, net of noncontrolling interests	393	22,631	(9,591)	4,729
Total assets	1,515,817	2,057,305	1,515,817	2,057,305	2,012,060
Operating Segments | Ethanol
Segment Reporting Information [Line Items]
Revenues from external customers	223,745	310,867	536,784	580,033
Income (loss) before income taxes, net of noncontrolling interests	868	3,749	(23,108)	6,760
Total assets	642,394	361,522	642,394	361,522	690,548
Operating Segments | Plant Nutrient
Segment Reporting Information [Line Items]
Revenues from external customers	279,825	270,577	404,738	399,102
Income (loss) before income taxes, net of noncontrolling interests	19,407	15,903	18,215	11,974
Total assets	342,690	381,924	342,690	381,924	383,781
Operating Segments | Rail
Segment Reporting Information [Line Items]
Revenues from external customers	35,442	43,016	72,555	84,431
Income (loss) before income taxes, net of noncontrolling interests	2,606	3,180	3,613	7,492
Total assets	656,573	657,617	656,573	657,617	693,931
Segment Reconciling Items
Segment Reporting Information [Line Items]
Revenues from external customers	2,455	2,676	5,556	4,152
Segment Reconciling Items | Trade
Segment Reporting Information [Line Items]
Revenues from external customers	432	631	1,040	812
Segment Reconciling Items | Plant Nutrient
Segment Reporting Information [Line Items]
Revenues from external customers	635	1,274	1,523	1,294
Segment Reconciling Items | Rail
Segment Reporting Information [Line Items]
Revenues from external customers	1,388	771	2,993	2,046
Other
Segment Reporting Information [Line Items]
Income (loss) before income taxes, net of noncontrolling interests	(5,035)	(4,578)	(10,015)	(9,505)
Total assets	$ 146,515	$ 113,491	$ 146,515	$ 113,491	$ 120,421