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Significant Accounting Policies (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Property, Plant and Equipment [Line Items] |  |  |
Excise taxes | $ 1,760.0 | $ 1,933.3 | $ 1,838.9
Interest costs capitalized | $ 1.4 | $ 1.4 | $ 2.2
LKE transaction, required term to facilitate forward agreement before proceeds are reclassified as available cash (in days) | 180 days |  |
Pipeline and terminal facilities | Minimum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Depreciable life (in years) | 16 years |  |
Pipeline and terminal facilities | Maximum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Depreciable life (in years) | 25 years |  |
Retail gasoline stations | Minimum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Depreciable life (in years) | 3 years |  |
Retail gasoline stations | Maximum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Depreciable life (in years) | 50 years |  |
Nonqualified Stock Options |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Award vesting period (in years) | 3 years |  |
Restricted Stock And Restricted Stock Units |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Award vesting period (in years) | 3 years |  |

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- Definition The amount of excise and sales taxes included in sales and revenues, which are then deducted as a cost of sales. Includes excise taxes, which are applied to specific types of transactions or items (such as gasoline or alcohol); and sales, use and value added taxes, which are applied to a broad class of revenue-producing transactions involving a wide range of goods and services. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(1)) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 + Details
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