Segment Information (Schedule Of Segment Reporting Information) (Details) (USD $)	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Segment Reporting Information [Line Items]
Sales and other revenues	$ 5,173,398,000	$ 2,090,988,000	$ 10,467,116,000	$ 6,111,138,000
Depreciation and amortization	43,240,000	29,138,000	106,380,000	85,719,000
Income (loss) from operations	869,207,000	107,618,000	1,358,485,000	217,038,000
Capital expenditures	117,918,000	51,409,000	274,223,000	127,939,000
Cash, cash equivalents and investments in marketable securities	1,759,353,000		1,759,353,000		230,444,000
Total assets	9,916,463,000		9,916,463,000		3,701,475,000
Long-term debt	1,224,987,000		1,224,987,000		810,561,000
HEP [Member]
Segment Reporting Information [Line Items]
Sales and other revenues	49,288,000	46,558,000	145,233,000	132,730,000
Depreciation and amortization	7,326,000	6,830,000	21,870,000	20,822,000
Income (loss) from operations	25,261,000	24,588,000	76,564,000	65,737,000
Capital expenditures	8,593,000	3,567,000	31,493,000	8,054,000
Cash, cash equivalents and investments in marketable securities	1,802,000		1,802,000		403,000
Total assets	685,463,000		685,463,000		669,820,000
Long-term debt	527,213,000		527,213,000		482,271,000
Segment revenues from external customers	8,300,000	9,200,000	33,000,000	24,700,000
Refining [Member]
Segment Reporting Information [Line Items]
Sales and other revenues	5,164,778,000	2,081,709,000	10,433,096,000	6,086,243,000
Depreciation and amortization	34,890,000	21,274,000	81,351,000	62,599,000
Income (loss) from operations	886,860,000	100,111,000	1,359,994,000	200,080,000
Capital expenditures	46,294,000	47,623,000	92,078,000	118,387,000
Cash, cash equivalents and investments in marketable securities
Total assets	3,114,748,000		3,114,748,000		2,490,193,000
Long-term debt
Corporate And Other [Member]
Segment Reporting Information [Line Items]
Sales and other revenues	299,000	100,000	1,100,000	317,000
Depreciation and amortization	1,231,000	1,329,000	3,780,000	3,183,000
Income (loss) from operations	(42,354,000)	(16,652,000)	(76,490,000)	(47,529,000)
Capital expenditures	63,031,000	219,000	150,652,000	1,498,000
Cash, cash equivalents and investments in marketable securities	1,757,551,000		1,757,551,000		230,041,000
Total assets	6,148,879,000		6,148,879,000		573,531,000
Long-term debt	714,349,000		714,349,000		345,215,000
Consolidations And Eliminations [Member]
Segment Reporting Information [Line Items]
Sales and other revenues	(40,967,000)	(37,379,000)	(112,313,000)	(108,152,000)
Depreciation and amortization	(207,000)	(295,000)	(621,000)	(885,000)
Income (loss) from operations	(560,000)	(429,000)	(1,583,000)	(1,250,000)
Capital expenditures
Cash, cash equivalents and investments in marketable securities
Total assets	(32,627,000)		(32,627,000)		(32,069,000)
Long-term debt	$ (16,575,000)		$ (16,575,000)		$ (16,925,000)

Cash, Cash Equivalents, And Investments In Marketable Securities

Name:	hoc_CashCashEquivalentsAndInvestmentsInMarketableSecurities
Namespace Prefix:	hoc
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Concepts (CON)

-Number 6

-Paragraph 25

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 18

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 7

+ Details

Name:	us-gaap_Assets
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ Details

Name:	us-gaap_DepreciationDepletionAndAmortization
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

+ Details

Name:	us-gaap_LongTermDebtNoncurrent
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ Details

Name:	us-gaap_OperatingIncomeLoss
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Revenue related to the downstream oil and gas activities, including the refining of crude oil, as well as the marketing and distribution of crude oil, refined petroleum products, and natural gas.

+ Details

Name:	us-gaap_RefiningAndMarketingRevenue
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Total expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment. Must be disclosed if the amount (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 28

-Subparagraph b

+ Details

Name:	us-gaap_SegmentReportingInformationExpendituresForAdditionsToLongLivedAssets
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ Details

Name:	us-gaap_SegmentReportingInformationLineItems
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Total revenues for reportable segments.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 32

-Subparagraph a

+ Details

Name:	us-gaap_SegmentReportingSegmentRevenue
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration