FINANCIAL INSTRUMENTS: (Tables)

6 Months Ended

Jun. 30, 2014

FINANCIAL INSTRUMENTS:

Schedule of carrying amount and estimated fair values of the Company's financial instruments

Consequently, such financial instruments are not included in the following table that provides information about the carrying amounts and estimated fair values of other financial instruments that are not measured at fair value in the condensed consolidated balance sheet as of June 30, 2014 and December 31, 2013 (in millions):

	As of June 30, 2014				As of December 31, 2013
	Carrying Value		Fair Value		Carrying Value		Fair Value
Liabilities:
Long-term debt	$	4,205.5	$	4,495.3	$	4,204.9	$	4,088.8

Schedule of fair values of assets and liabilities measured at fair value on a recurring basis

	Fair Value at Measurement Date Using:								Fair Value at Measurement Date Using:
	Fair Value as ofJune 30,		Quoted prices in active markets for identical assets		Significant other observable inputs		Significant unobservable inputs		Fair Value as ofDecember		Quoted prices in active markets for identical assets		Significant other observable inputs		Significant unobservable inputs
Description	2014		(Level 1)		(Level 2)		(Level 3)		31, 2013		(Level 1)		(Level 2)		(Level 3)
Assets:
Short term investment:
- Trading securities	$	284.4	$	284.4					$	202.6	$	202.6
- Available for sale debt securities:
Corporate bonds	0.4				$	0.4			0.4				$	0.4
Asset backed obligations	0.1				0.1				0.1				0.1
Mortgage backed securities	5.0				5.0				5.2				5.2
Accounts receivable:
- Derivatives — Not classified as hedges:
Provisionally priced sales:
Copper	99.7		99.7						53.9		53.9
Molybdenum	113.4		113.4		—		—		100.2		100.2		—		—
Total	$	503.0	$	497.5	$	5.5	$	—	$	362.4	$	356.7	$	5.7	$	—