Basis of Consolidation

3 Months Ended

Mar. 31, 2011

Basis of consolidation [Abstract]

Basis of consolidation

2	Basis of consolidation
	All majority-owned subsidiaries in which we have both share and management control are consolidated. All significant intercompany accounts and transactions are eliminated. Subsidiaries over which control is achieved through other means, such as stockholders agreement, are also consolidated even if we hold less than 51% of voting capital. Our variable interest entities in which we are the primary beneficiary are consolidated. Investments in unconsolidated affiliates and joint ventures are accounted for under the equity method (Note 10).
	We evaluate the carrying value of our equity investments in relation to publicly quoted market prices when available. If the quoted market price is below book value, and such decline is considered other than temporary, we write-down our equity investments to quoted market value.
	We define joint ventures as businesses in which we and a small group of other partners each participate actively in the overall entity management, based on a stockholders agreement. We define affiliates as businesses in which we participate as a noncontrolling interest but with significant influence over the operating and financial policies of the investee.
	Our participation in hydroelectric projects in Brazil is made via consortium contracts under which we have undivided interests in the assets, and are liable for our proportionate share of liabilities and expenses, which are based on our proportionate share of power output. We do not have joint liability for any obligations. No separate legal or tax status is granted to consortia under Brazilian law. Accordingly, we recognize our proportionate share of costs and our undivided interest in assets relating to hydroelectric projects.