Revenue Recognition - Revenue Disaggregation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	$ 438,326		$ 1,245,020
Total revenues	467,891	$ 295,311	1,307,564	$ 913,600
Goods transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	424,061		1,203,511
Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	14,265		41,509
Revenues from contracts with customers
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	438,326		1,245,020
Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	29,565		62,544
Marketing
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	424,061		1,203,511
Total revenues	453,626		1,266,055
Marketing | Goods transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	424,061		1,203,511
Marketing | Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	0		0
Marketing | Revenues from contracts with customers
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	424,061		1,203,511
Marketing | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	29,565		62,544
Transportation
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	14,265		41,509
Total revenues	14,265		41,509
Transportation | Goods transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	0		0
Transportation | Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	14,265		41,509
Transportation | Revenues from contracts with customers
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	14,265		41,509
Transportation | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	$ 0		$ 0