Consolidated Statement of Equity (Unaudited) (USD $) In Millions, unless otherwise specified	Total	Total FCX Stockholders' Equity [Member]	Common Stock [Member]	Capital in Excess of Par Value [Member]	Retained Earnings (Deficit) [Member]	Accumulated Other Comprehensive Loss [Member]	Common Stock Held in Treasury [Member]	Noncontrolling Interest [Member]
Balance at Dec. 31, 2012	$ 21,311	$ 17,543	$ 107	$ 19,119	$ 2,399	$ (506)	$ (3,576)	$ 3,768
Balance (in shares) at Dec. 31, 2012			1,073				124
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercised and issued stock-based awards	2	2	0	2	0	0	0	0
Exercised and issued stock-based awards (in shares)			1				0
Stock-based compensation	41	41	0	41	0	0	0	0
Tax benefit for stock-based awards	1	1	0	1	0	0	0	0
Tender of shares for stock-based awards	(4)	(4)	0	0	0	0	(4)	0
Tender of shares for stock-based awards (in shares)			0				0
Dividends on common stock	(297)	(297)	0	0	(297)	0	0	0
Dividends to noncontrolling interests	(35)	0	0	0	0	0	0	(35)
Total comprehensive income	830	654	0	0	648	6	0	176
Balance at Mar. 31, 2013	$ 21,849	$ 17,940	$ 107	$ 19,163	$ 2,750	$ (500)	$ (3,580)	$ 3,909
Balance (in shares) at Mar. 31, 2013			1,074				124