Significant Accounting Policies (Unaudited) (Policies)

6 Months Ended

Jun. 30, 2013

Significant Accounting Policies [Abstract]

Consolidation, Policy [Policy Text Block]

Basis of Presentation. FCX began consolidating its wholly owned subsidiaries, PXP and MMR, effective June 1, 2013, and June 4, 2013, respectively. PXP's and MMR's financial information consolidates the results of operations and the assets and liabilities for their majority-owned subsidiaries. Investments in unincorporated joint ventures, as well as individual interests in oil and gas exploration, development and production activities, are reflected using the proportionate consolidation method. All significant intercompany transactions have been eliminated.

Use of Estimates, Policy [Policy Text Block]

Use of Estimates. As a result of the acquisition of PXP and MMR, other significant areas requiring the use of management estimates include oil and natural gas reserve estimation; timing of transfers of oil and gas properties not subject to amortization into the full cost pool; determination of fair value of assets acquired, liabilities assumed and noncontrolling interest, and recognition of goodwill and deferred taxes in connection with business combinations; and valuation of derivative instruments. Actual results could differ from those estimates. In particular, initial estimates of acquisition fair values are preliminary and subject to change as the related valuations are finalized.

Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block]

Goodwill.Goodwill has an indefinite useful life and is not amortized, but rather is tested for impairment at least annually, unless events occur or circumstances change between annual tests that would more likely than not reduce the fair value of a related reporting unit below its carrying value. Impairment occurs when the carrying amount of goodwill exceeds its implied fair value. FCX uses a discounted cash flow model to determine if the carrying value of the reporting unit, including goodwill, is less than the fair value of the reporting unit. FCX's approach to allocating goodwill includes the identification of the reporting unit it believes has contributed to the excess purchase price and includes consideration of the reporting unit's potential for future growth. Goodwill arose with FCX's acquisitions of PXP and MMR, which has been allocated to the oil and gas reporting unit. Events affecting oil and gas prices may cause a decrease in the fair value of the reporting unit, and FCX could have an impairment of its goodwill in future periods. When a sale of oil and gas properties occurs, goodwill is allocated to that property based on the relationship of the fair value of the property sold to the total reporting unit's fair value. A significant sale of oil and gas properties may represent a triggering event that requires goodwill to be evaluated for impairment.

Oil and Gas Properties Policy [Policy Text Block]

Oil and Gas Properties. FCX follows the full cost method of accounting whereby all costs associated with oil and gas property acquisitions, exploration and development activities are capitalized. Such costs include internal general and administrative costs, such as payroll and related benefits and costs directly attributable to employees engaged in acquisition, exploration and development activities. General and administrative costs associated with production, operations, marketing and general corporate activities are expensed as incurred. Capitalized costs, along with estimated future costs to develop proved reserves and asset retirement costs that are not already included in oil and gas properties, net of related salvage value, are amortized to expense under the unit-of-production method using engineers' estimates of proved oil and natural gas reserves. The costs of unproved oil and gas properties are excluded from amortization until the properties are evaluated. Interest is capitalized on oil and gas properties not subject to amortization and in the process of development. Proceeds from the sale of oil and gas properties are accounted for as reductions to capitalized costs unless such sales cause a 25 percent or greater change in the total proved reserves of oil and gas attributable to a cost center, in which case a gain or loss is recognized.

As of June 30, 2013, property, plant, equipment and development costs, net on the condensed consolidated balance sheet included $12.2 billion for oil and natural gas properties subject to depletion and $11.4 billion for oil and natural gas properties not subject to depletion.

Under the Securities and Exchange Commission's (SEC) full cost accounting rules, FCX reviews the carrying value of its oil and gas properties each quarter on a country-by-country basis, with each country representing a cost center. FCX currently has one cost center, the U.S. Under these rules, capitalized costs of oil and gas properties (net of accumulated depreciation, depletion and amortization, and related deferred income taxes) for each cost center may not exceed a “ceiling” equal to:

• the present value, discounted at 10 percent, of estimated future net cash flows from proved oil and gas reserves, net of estimated future income taxes; plus

• the cost of unproved properties not being amortized; plus

• the lower of cost or estimated fair value of unproved properties included in the costs being amortized (net of related tax effects).

These rules generally require that FCX price its future oil and gas production at the trailing twelve-month average of the first-day-of-the-month reference prices as adjusted for location and quality differentials. FCX reference prices are the West Texas Intermediate, or WTI, for oil and the Henry Hub spot price for gas. Such prices are utilized except where different prices are fixed and determinable from applicable contracts for the remaining term of those contracts. The reserve estimates exclude the effect of any oil and gas derivatives FCX has in place. The estimated future net cash flows exclude future cash outflows associated with settling asset retirement obligations included in the net book value of the oil and gas properties. The rules require an impairment if the capitalized costs exceed this “ceiling.” At June 30, 2013, the ceiling with respect to FCX's oil and gas properties exceeded the net capitalized costs, and therefore, FCX did not record an impairment.