Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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Amount of consideration transferred for working capital, consisting of acquisition-date fair value of current assets transferred by the acquirer, net of cash acquired, and current liabilities incurred by the acquirer.

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Terminal Storage Capacity

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Acquisition (Details)		6 Months Ended
Acquisition (Details)	May 14, 2018 USD ($) MBbls	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)
Business Acquisition (Textual)
Amount paid from available cash on hand		$ 471,000,000	$ 0
Pure Biofuels [Member]
Business Acquisition (Textual)
Percent equity interests acquired	100.00%
Amount paid from available cash on hand	$ 471,000,000
Payments for working capital	122,000,000
Identifiable intangible assets	210,000,000
Goodwill	$ 228,000,000
Expected amortization period of identifiable intangible assets	10 years
Total amount of goodwill expected to be deductible for tax purposes	$ 0
Pure Biofuels [Member] \| Port of Callao Terminal [Member]
Business Acquisition (Textual)
Approximate storage capacity of terminal (in thousands of barrels) \| MBbls	1,000
Pure Biofuels [Member] \| Paita Terminal [Member]
Business Acquisition (Textual)
Approximate storage capacity of terminal (in thousands of barrels) \| MBbls	180