Changes In Business And Other Matters (Narrative) (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended			3 Months Ended			3 Months Ended		12 Months Ended		0 Months Ended	1 Months Ended	12 Months Ended			0 Months Ended	12 Months Ended	3 Months Ended				3 Months Ended		6 Months Ended	3 Months Ended
	Jan. 31, 2011	Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2011	Mar. 31, 2012 Stock Compensation Modification [Member]	Mar. 31, 2011 Business Improvement Initiatives [Member]	Jan. 31, 2011 Harold Keene Coal Co., Inc. [Member]	Mar. 31, 2012 Toledo Refinery And Related Inventory [Member]	Mar. 31, 2011 Toledo Refinery And Related Inventory [Member] D Y	Dec. 31, 2011 Toledo Refinery And Related Inventory [Member]	Mar. 01, 2011 Toledo Refinery And Related Inventory [Member] Y	Mar. 02, 2011 Toledo Refinery And Related Inventory [Member] Cash [Member]	Feb. 29, 2012 Toledo Refinery And Related Inventory [Member] Note Receivable [Member]	Dec. 31, 2011 Toledo Refinery And Related Inventory [Member] Note Receivable [Member]	Mar. 01, 2011 Toledo Refinery And Related Inventory [Member] Note Receivable [Member]	Mar. 01, 2011 Toledo Refinery And Related Inventory [Member] Two-Year Note Receivable [Member]	Mar. 02, 2011 Toledo Refinery And Related Inventory [Member] Working Capital Adjustments [Member]	Dec. 31, 2011 Toledo Refinery And Related Inventory [Member] Crude Oil And Refined Product Inventories [Member]	Sep. 30, 2011 Refineries Long-Lived Assets [Member]	Jun. 30, 2010 Polypropylene Chemicals Operations [Member]	Mar. 31, 2012 Philadelphia And Marcus Hook Refineries [Member]	Dec. 31, 2011 Philadelphia And Marcus Hook Refineries [Member]	Mar. 31, 2012 Philadelphia And Marcus Hook Refineries [Member] Crude Oil And Refined Product Inventories [Member]	Mar. 31, 2012 Philadelphia And Marcus Hook Refineries [Member] Severance, Contract Terminations And Idling Expenses [Member]	Dec. 31, 2011 Philadelphia And Marcus Hook Refineries [Member] Severance, Contract Terminations And Idling Expenses [Member]	Mar. 31, 2012 Philadelphia And Marcus Hook Refineries [Member] Severance, Contract Terminations And Idling Expenses [Member] North East Refineries [Member]	Mar. 31, 2012 SunCoke Energy, Inc. [Member]
Changes In Business And Other Matters [Line Items]
Purchase price							$ 52
Cash paid for acquisitions							38
Contingent consideration payment							14
Number of active underground mines acquired	2
Number of active surface and highwall mines acquired	1
Estimated fair value of long-lived assets		103
Net proceeds from divestment of business											1,037
Cash received on divestment of business												546	182	309			6			348
Pre-tax (gain) loss on divestment of business								104	15	2
Notes receivable															285
Note receivable from sale				182												200
Notes receivable maturity period, day									90		2
Maximum payments for participation								125
Net after-tax gain on divestment								61	4	4
LIFO inventory loss (profit) pre-tax																		535			1,500
Period of purchase agreement, in years									3													10
Provision to write down certain assets, before tax		109	6																2,363		35			275	248	35
Provision to write down certain assets, after tax		63	4																1,405		21				144	21
LIFO liquidation pre-tax gains																							497
LIFO liquidation after-tax gains																							302
Hedging losses, pre-tax																							30
Hedging losses, after-tax																							18
Effect of LIFO Inventory Liquidation on Income																		535			1,500
Environmental remediation charges pre-tax		53
Environmental Cost Recognized After Tax		31
Provision to write down certain assets, before tax						6
Provision to write down certain assets, after tax						4
Stock compensation modification additional expense					21																						10
Stock compensation modification additional expense, after-tax					$ 11