Subsequent Events (Unaudited)	6 Months Ended
Jun. 30, 2014
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS Mining Contract - Indonesia. On July 25, 2014, PT-FI entered into a Memorandum of Understanding (MOU) with the Indonesian government under which PT-FI and the government have agreed to negotiate an amended Contract of Work (COW) to address provisions related to the size of PT-FI’s concession area, royalties and taxes, domestic processing and refining, divestment, local content, and continuation of operations post-2021. Under the MOU, provisions to be addressed in the negotiation of an amended COW include provisions for the development of new copper smelting and refining capacity in Indonesia, which will take into consideration an equitable sharing of costs between PT-FI (and any partners in the project) and the Indonesian government through fiscal incentives, provisions for divestment to the Indonesian government and/or Indonesian nationals of up to a 30 percent interest (an additional 20.64 percent interest) in PT-FI at fair value, and continuation of operations from 2022 through 2041. Negotiations will take into consideration PT-FI’s need for assurance of legal and fiscal terms post-2021 for PT-FI to continue with its large-scale investment program for the development of its underground reserves. The negotiations are expected to be completed within six months. Effective with the signing of the MOU, PT-FI agreed to provide a $115 million assurance bond to support its commitment for smelter development, to increase royalties to 4.0 percent for copper and 3.75 percent for gold from the previous rates of 3.5 percent for copper and 1.0 percent for gold, and to pay export duties set forth in a new regulation. On July 25, 2014, the Indonesian government revised its January 2014 regulations (as discussed in Note 13 of FCX’s annual report on Form 10-K for the year ended December 31, 2013) regarding export duties to incorporate reduced rates for copper concentrate exports for companies engaged in smelter development. The revised regulations provide for duties on copper concentrate exports during smelter development initially at 7.5 percent, declining to 5.0 percent when development progress exceeds 7.5 percent and is eliminated when development progress exceeds 30 percent. Under the MOU, no terms of the COW other than those relating to the export duties, smelter bond and royalties described previously will be changed until the completion of the amended COW. FCX evaluated events after June 30, 2014, and through the date the consolidated financial statements were issued, and determined any events or transactions occurring during this period that would require recognition or disclosure are appropriately addressed in these consolidated financial statements.

SUBSEQUENT EVENTS

Mining Contract - Indonesia. On July 25, 2014, PT-FI entered into a Memorandum of Understanding (MOU) with the Indonesian government under which PT-FI and the government have agreed to negotiate an amended Contract of Work (COW) to address provisions related to the size of PT-FI’s concession area, royalties and taxes, domestic processing and refining, divestment, local content, and continuation of operations post-2021.

Under the MOU, provisions to be addressed in the negotiation of an amended COW include provisions for the development of new copper smelting and refining capacity in Indonesia, which will take into consideration an equitable sharing of costs between PT-FI (and any partners in the project) and the Indonesian government through fiscal incentives, provisions for divestment to the Indonesian government and/or Indonesian nationals of up to a 30 percent interest (an additional 20.64 percent interest) in PT-FI at fair value, and continuation of operations from 2022 through 2041. Negotiations will take into consideration PT-FI’s need for assurance of legal and fiscal terms post-2021 for PT-FI to continue with its large-scale investment program for the development of its underground reserves. The negotiations are expected to be completed within six months.

Effective with the signing of the MOU, PT-FI agreed to provide a $115 million assurance bond to support its commitment for smelter development, to increase royalties to 4.0 percent for copper and 3.75 percent for gold from the previous rates of 3.5 percent for copper and 1.0 percent for gold, and to pay export duties set forth in a new regulation. On July 25, 2014, the Indonesian government revised its January 2014 regulations (as discussed in Note 13 of FCX’s annual report on Form 10-K for the year ended December 31, 2013) regarding export duties to incorporate reduced rates for copper concentrate exports for companies engaged in smelter development. The revised regulations provide for duties on copper concentrate exports during smelter development initially at 7.5 percent, declining to 5.0 percent when development progress exceeds 7.5 percent and is eliminated when development progress exceeds 30 percent.

Under the MOU, no terms of the COW other than those relating to the export duties, smelter bond and royalties described previously will be changed until the completion of the amended COW.

FCX evaluated events after June 30, 2014, and through the date the consolidated financial statements were issued, and determined any events or transactions occurring during this period that would require recognition or disclosure are appropriately addressed in these consolidated financial statements.