Holly-Frontier Merger (Narrative) (Details) (USD $)	6 Months Ended
Jun. 30, 2011
Holly-Frontier Merger
Shares converted at acquisition	51.4
Common stock to be issued per share of Frontier stock	0.4811
Market closing price, per share	$ 71.86
Aggregate consideration paid in connection with merger	$ 3,700,000,000
Merger transaction costs recognized	$ 6,000,000

Noncash or Part Noncash Acquisition, Noncash Financial or Equity Instrument Consideration, Shares Issued Per Share

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph d

+ Details

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- Definition

Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph d

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 24

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- Details

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- Definition

The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 32

+ Details

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- Definition

The dollar amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 5
-Section H

+ Details

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