BORCO Acquisition - Purchase Price Allocated to Tangible and Intangible Assets Acquired (Detail) (Bahamas Oil Refining Company International Limited, USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Jan. 18, 2011
Bahamas Oil Refining Company International Limited
Schedule of Business Acquisitions, Purchase Price Allocation [Line Items]
Current assets	$ 40,842
Inventory	1,645
Property, plant and equipment	1,129,961
Intangible assets	191,000
Other assets	415
Goodwill	490,536
Current liabilities	(54,627)
Debt	(318,167)	(318,167)
Other liabilities	(57,418)
Allocated purchase price	$ 1,424,187

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The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

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The amount of acquisition cost of a business combination allocated to current assets.

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The amount of acquisition cost of a business combination allocated to inventory, including finished goods, work-in-process, and raw materials.

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- Definition

The amount of acquisition cost of a business combination allocated to current liabilities of the acquired entity.

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Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

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The amount of acquisition cost of a business combination allocated to the noncurrent portion of the long-term debt assumed from the acquired entity.

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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The amount of acquisition cost of a business combination allocated to noncurrent assets of the acquired entity, except for property plant and equipment, intangible assets, and goodwill.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The amount of acquisition cost of a business combination allocated to other noncurrent liabilities of the acquired entity.

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The amount of acquisition cost of a business combination allocated to property, plant and equipment to be used in ongoing operations.

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