Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 31, 2011	Sep. 30, 2011	Dec. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows from operating activities:
Net income	$ 4,573	$ 4,911	$ 6,048	$ 22,652	$ 17,453	$ 5,456
Adjustments to reconcile net income to cash from operations:
Depreciation, depletion and amortization	1,168	1,018	1,073	4,122	3,260	2,722
Dividends received	205	240	629	1,038	1,161	386
Equity in results of affiliates, joint ventures and other investments	(167)	(282)	(303)	(1,135)	(987)	(433)
Deferred income taxes	109	(846)	(412)	(265)	(1,291)	16
Loss on disposal of property, plant and equipment	15	17	248	223	623	293
Gain on sale of assets available for sale				(1,513)		(40)
Discontinued operations, net of tax					143
Foreign exchange and indexation gains, net	808	2,218	(595)	2,879	(787)	(1,095)
Unrealized derivative losses (gains), net	290	642	532	490	594	(1,382)
Unrealized interest (income) expense, net	150	78	(43)	194	187	(25)
Others	(68)	(37)	(27)	(183)	58	20
Decrease (increase) in assets:
Accounts receivable	456	(730)	(639)	(821)	(3,800)	616
Inventories	(203)	(324)	404	(1,343)	(425)	530
Recoverable taxes	20	(392)	(70)	(563)	42	108
Others	(16)	(219)	709	(315)	307	(455)
Increase (decrease) in liabilities:
Suppliers	(156)	829	(445)	1,076	928	121
Payroll and related charges	225	212	204	285	214	159
Income taxes	(185)	(2,745)	(93)	(2,478)	1,311	(234)
Others	288	(379)	(35)	153	192	373
Net cash provided by operating activities	7,512	4,211	7,185	24,496	19,183	7,136
Cash flows from investing activities:
Short term investments			(1,793)	1,793	1,954	(1,439)
Related parties
Loan proceeds					(28)	(181)
Repayments						7
Others	(58)	57	(17)	(178)	(30)	(25)
Judicial deposits	(59)	(239)	96	(186)	(94)	(132)
Investments	(345)	(18)	(36)	(504)	(87)	(1,947)
Additions to property, plant and equipment	(6,071)	(3,711)	(4,742)	(16,075)	(12,647)	(8,096)
Proceeds from disposal of investments				1,081		606
Acquisition (sale) of subsidiaries					(6,252)	(1,952)
Net cash used in investing activities	(6,533)	(3,911)	(6,492)	(14,069)	(17,184)	(13,159)
Short-term debt
Additions	21	20	229	859	2,233	1,285
Repayments	(36)	(63)	(147)	(955)	(2,132)	(1,254)
Related parties
Proceeds			2	19	24	16
Repayments			(22)	(1)	(25)	(373)
Third parties
Proceeds	214	479	891	1,564	4,436	3,104
Repayments	(82)	(769)	(958)	(2,621)	(2,629)	(307)
Treasury stock	(1,001)	(2,001)	(1,132)	(3,002)	(1,510)	(9)
Mandatorily convertible notes						934
Transactions of noncontrolling interest	(1,134)			(1,134)	660
Dividends and interest attributed to Company's stockholders	(3,000)	(3,000)	(1,750)	(9,000)	(3,000)	(2,724)
Dividends and interest attributed to noncontrolling interest	(40)		(81)	(100)	(140)	(47)
Net cash provided by (used in) financing activities	(5,058)	(5,334)	(2,968)	(14,371)	(2,083)	625
Increase (decrease) in cash and cash equivalents	(4,079)	(5,034)	(2,275)	(3,944)	(84)	(5,398)
Effect of exchange rate changes on cash and cash equivalents	45	(628)	136	(109)	375	2,360
Cash and cash equivalents, beginning of period	7,565	13,227	9,723	7,584	7,293	10,331
Cash and cash equivalents, end of period	3,531	7,565	7,584	3,531	7,584	7,293
Cash paid during the period for:
Interest on short-term debt	(1)		(2)	(3)	(5)	(1)
Interest on long-term debt	(198)	(234)	(314)	(1,143)	(1,097)	(1,113)
Income tax	(1,060)	(4,097)	(1,100)	(7,293)	(1,972)	(1,331)
Non-cash transactions
Income tax paid with credits	(681)			(681)
Interest capitalized	$ 78	$ 54	$ 38	$ 234	$ 164	$ 266

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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).