Quarterly report pursuant to Section 13 or 15(d)

Segment Information (Narrative) (Details)

v3.19.1
Segment Information (Narrative) (Details)
3 Months Ended
Mar. 31, 2019
segment
Concentration Risk [Line Items]  
Number of reportable operating segments 2
Sales Revenue, Net [Member] | Glencore and Mercuria [Member]  
Concentration Risk [Line Items]  
Concentration risk, percentage 100.00%