Consolidated Statements of Cash Flows (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Cash flows from operating activities:
Net income (loss)	$ (432)	$ 98
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization expense	384	365
Asset impairment loss	611	0
Noncash interest expense and other income, net	7	7
Stock-based compensation expense	10	12
Deferred income tax expense (benefit)	61	(44)
Changes in current assets and current liabilities	1,063	1,603
Changes in deferred charges and credits and other operating activities, net	0	17
Net cash provided by operating activities	1,704	2,058
Cash flows from investing activities:
Capital expenditures	(726)	(438)
Deferred turnaround and catalyst costs	(158)	(299)
Advance payment related to acquisition of Pembroke Refinery	0	(37)
Other investing activities, net	10	(9)
Net cash used in investing activities	(874)	(783)
Non-bank debt:
Repayments	0	(510)
Accounts receivable sales program:
Repayments	(150)	0
Purchase of common stock for treasury	(106)	0
Proceeds from the exercise of stock options	9	21
Common stock dividends	(83)	(28)
Contributions from noncontrolling interest	11	0
Other financing activities, net	0	5
Net cash used in financing activities	(319)	(512)
Effect of foreign exchange rate changes on cash	24	36
Net increase in cash and temporary cash investments	535	799
Cash and temporary cash investments at beginning of period	1,024	3,334
Cash and temporary cash investments at end of period	$ 1,559	$ 4,133

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).