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v3.8.0.1

Accounting Policies Property, Plant and Equipment (Details) | 12 Months Ended
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Dec. 31, 2017
Minimum | Building and building improvements |
Estimated useful life (years) | 15 years
Minimum | Pipelines, tanks and terminals |
Estimated useful life (years) | 15 years
Minimum | Asset retirement obligation assets |
Estimated useful life (years) | 15 years
Minimum | Other equipment |
Estimated useful life (years) | 3 years
Maximum | Building and building improvements |
Estimated useful life (years) | 40 years
Maximum | Pipelines, tanks and terminals |
Estimated useful life (years) | 40 years
Maximum | Asset retirement obligation assets |
Estimated useful life (years) | 50 years
Maximum | Other equipment |
Estimated useful life (years) | 15 years

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- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Details
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Namespace Prefix: |
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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Period Type: |