Summary of Significant Accounting Policies - Risk(Details) - Product
|
12 Months Ended |
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
| Sales Revenue |
|
|
|
| Concentration of Risk |
|
|
|
| Percentage of consolidated total |
100.00%
|
100.00%
|
100.00%
|
| Sales Revenue | Gasoline sales: gasoline and gasoline blendstocks (such as ethanol) |
|
|
|
| Concentration of Risk |
|
|
|
| Percentage of consolidated total |
64.00%
|
59.00%
|
60.00%
|
| Sales Revenue | Crude oil sales and crude oil logistics revenue |
|
|
|
| Concentration of Risk |
|
|
|
| Percentage of consolidated total |
7.00%
|
12.00%
|
14.00%
|
| Sales Revenue | Distillates (home heating oil, diesel and kerosene), residual oil, natural gas and propane sales |
|
|
|
| Concentration of Risk |
|
|
|
| Percentage of consolidated total |
24.00%
|
25.00%
|
25.00%
|
| Sales Revenue | Convenience store sales, rental income and sundry sales |
|
|
|
| Concentration of Risk |
|
|
|
| Percentage of consolidated total |
5.00%
|
4.00%
|
1.00%
|
| Product Margin [Member] |
|
|
|
| Concentration of Risk |
|
|
|
| Percentage of consolidated total |
100.00%
|
100.00%
|
100.00%
|
| Product Margin [Member] | Wholesale Segment |
|
|
|
| Concentration of Risk |
|
|
|
| Percentage of consolidated total |
23.00%
|
30.00%
|
48.00%
|
| Product Margin [Member] | GDSO |
|
|
|
| Concentration of Risk |
|
|
|
| Percentage of consolidated total |
73.00%
|
66.00%
|
47.00%
|
| Product Margin [Member] | Commercial Segment |
|
|
|
| Concentration of Risk |
|
|
|
| Percentage of consolidated total |
4.00%
|
4.00%
|
5.00%
|