Holly-Frontier Merger (Assets And Liabilities Recognized In Merger, Fair Value Estimates) (Details) (USD $) In Millions	Sep. 30, 2011
Holly-Frontier Merger [Abstract]
Cash and cash equivalents	$ 872
Accounts receivable	738
Inventories	670
Properties, plants and equipment	1,052
Goodwill	2,235
Income taxes receivable	38
Other assets	12
Accounts payable	(1,072)
Accrued liabilities	(41)
Long-term debt	(371)
Other long-term liabilities	(65)
Deferred income taxes	(361)
Net tangible and intangible assets acquired and liabilities assumed	$ 3,707

Business Acquisition Purchase Price Allocation Income Taxes Receivable Amount

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The total purchase price of the acquired entity. This includes cash paid to equity interest holders of the acquired entity, fair value of debt and equity securities issued to equity holders of the acquired entity, and transaction costs paid to third parties to consummate the acquisition.

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The amount of cash and cash equivalents acquired in a business combination.

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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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The amount of acquisition cost of a business combination allocated to receivables.

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The amount of acquisition cost of a business combination allocated to accounts payable of the acquired entity.

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The amount of acquisition cost of a business combination allocated to accrued expenses of the acquired entity.

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Amount of deferred tax assets or liabilities for the differences between the values assigned and the tax bases of assets and liabilities in a business combination, net of any valuation allowance for deferred tax assets.

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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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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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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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