Quarterly report pursuant to Section 13 or 15(d)

Segment Information (Narrative) (Details)

v3.19.2
Segment Information (Narrative) (Details)
6 Months Ended
Jun. 30, 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%