Fair Value Measurements

9 Months Ended

Sep. 30, 2012

Fair Value Disclosures [Abstract]

Fair Value Measurements

Fair Value Measurements:

Assets and Liabilities Measured at Fair Value on a Recurring Basis

The following table presents the fair value hierarchy for those assets and liabilities measured at fair value on a recurring basis (in millions):

	Quoted Prices in Active Markets for Identical Assets (Level 1)
	As of September 30, 2012		As of December 31, 2011
Assets:
Investment in marketable equity securities (1)	$	10.1	$	8.4

(1) Investment in marketable equity securities is recorded in Other Assets, net in the accompanying Consolidated Balance Sheets.

Other Fair Value Measurements

The carrying amounts of cash and cash equivalents, accounts and notes receivable, net, accounts payable, other current liabilities, and short-term debt approximate fair value due to the short maturities of these instruments. The fair values of each of our long-term debt instruments are based on the quoted market prices for the same issues or on the amount of future cash flows associated with each instrument using current market rates for debt instruments of similar maturities and credit risk. The fair values presented are estimates and are not necessarily indicative of amounts for which we could settle such instruments currently or indicative of our intent or ability to dispose of or liquidate them. The estimated fair value of our debt was as follows (in millions):

	As of September 30, 2012		As of December 31, 2011
Senior unsecured notes	$	219.4	$	207.0