Amount of convertible notes tendered in exchange offer.

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Shares that could be issued due to the conversion of warrants.

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Payments for cost of note hedges.

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Percentage of convertible notes tendered in exchange offer.

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Premium over the closing price of the Companys shares of common stock included in strick price

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Strike Price Of Warrants

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The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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The price per share of the conversion feature embedded in the debt instrument.

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The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Interest rate stated in the contractual debt agreement.

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Date the debt instrument was issued, in CCYY-MM-DD format.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Represents the charge against earnings during the period for commitment fees and debt issuance expenses.

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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

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Long-Term Debt (Convertible Notes) (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended				0 Months Ended	12 Months Ended		0 Months Ended								12 Months Ended	0 Months Ended	2 Months Ended
	Dec. 31, 2012	Dec. 31, 2012 Subordinated Convertible Notes Due 2029 [Member]	Dec. 31, 2012 1.00% Senior Convertible Notes Due 2012 [Member]	Dec. 15, 2009 1.00% Senior Convertible Notes Due 2012 [Member]	Nov. 30, 2006 0.875% Convertible Notes Due 2013 [Member]	Dec. 31, 2012 0.875% Convertible Notes Due 2013 [Member]	Jul. 22, 2011 0.875% Convertible Notes Due 2013 [Member]	Dec. 15, 2009 North America [Member] Subordinated Convertible Notes Due 2029 [Member]	Dec. 31, 2012 North America [Member] Subordinated Convertible Notes Due 2029 [Member]	Dec. 31, 2011 North America [Member] Subordinated Convertible Notes Due 2029 [Member]	Dec. 31, 2012 North America [Member] 1.00% Senior Convertible Notes Due 2012 [Member]	Dec. 31, 2011 North America [Member] 1.00% Senior Convertible Notes Due 2012 [Member]	Dec. 15, 2009 North America [Member] 1.00% Senior Convertible Notes Due 2012 [Member]	Dec. 31, 2008 North America [Member] 1.00% Senior Convertible Notes Due 2012 [Member]	Sep. 30, 2007 North America [Member] 1.00% Senior Convertible Notes Due 2012 [Member]	Dec. 31, 2012 North America [Member] 1.00% Senior Convertible Notes Due 2012 [Member] Phelps Dodge International Corporation [Member]	Nov. 30, 2006 North America [Member] 0.875% Convertible Notes Due 2013 [Member]	Dec. 31, 2006 North America [Member] 0.875% Convertible Notes Due 2013 [Member]	Dec. 31, 2012 North America [Member] 0.875% Convertible Notes Due 2013 [Member]	Dec. 31, 2011 North America [Member] 0.875% Convertible Notes Due 2013 [Member]
Debt Instrument [Line Items]
Debt principal amount							$ 355.0	$ 429.5					$ 10.6		$ 475.0		$ 355.0
Nonconvertible debt borrowing rate on debt instrument issuance date						0.875%		12.50%						7.50%			7.35%
Liability component of convertible notes								162.9	429.5	429.5	0	10.6	389.7		348.2		230.9		355.0	355.0
Unamortized discount								266.6	263.0	264.4	0	0.5	74.7		126.8		124.1		20.4	40.6
Debt issuance fees and expenses								14.5
Percentage of convertible notes tendered in exchange offer				97.80%							97.80%
Amount of convertible notes tendered in exchange offer				464.4							464.4
Interest rate			1.00%	1.00%		0.875%					1.00%	1.00%	1.00%				0.875%		0.875%	0.875%
Debt instrument original issuance date			Sep. 30, 2007		Nov. 30, 2006
Cost of acquired entity																707.6
Payment of issuance costs and expenses of related to notes																12.3		9.4
Conversion price per share		$ 36.75	$ 83.93			$ 50.36											$ 50.36
Common stock covered under note hedges		11,686,075	5,659,245			7,048,880											7,048,880
Strike price of warrants, per share	$ 76.00																$ 76.00
Premium over the closing price of the Companys shares of common stock included in strick price																	92.40%
Payment of outstanding debt including accrued interest, under the Company's amended credit facility																		87.8
Payments for cost of note hedges																		124.5
Proceeds from the issuance of the warrants																		80.4
Net increase in cash from receipt of the funds from convertible notes and related payments used for general																		$ 213.7