Revenue Recognition - Revenue Disaggregation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	$ 432,991		$ 806,694
Total revenues	452,417	$ 315,202	839,673	$ 618,289
Goods transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	419,365		779,450
Services transferred over time
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	13,626		27,244
Revenues from contracts with customers
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	432,991		806,694
Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	19,426		32,979
Marketing
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	419,365		779,450
Total revenues	438,791		812,429
Marketing | Goods transferred at a point in time
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	419,365		779,450
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	419,365		779,450
Marketing | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	19,426		32,979
Transportation
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	13,626		27,244
Total revenues	13,626		27,244
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	13,626		27,244
Transportation | Revenues from contracts with customers
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	13,626		27,244
Transportation | Other
Disaggregation of Revenue [Line Items]
Total revenues from contracts with customers	$ 0		$ 0