FAIR VALUE

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in the principal or most advantageous market in an orderly transaction between marketplace participants. Various valuation approaches can be used to determine fair value, each requiring different valuation inputs. The following hierarchy classifies the inputs used to determine fair value into three levels:


•	Level 1 - quoted prices in active markets for identical assets or liabilities;


•	Level 2 - inputs, other than quoted prices, observable by a marketplace participant either directly or indirectly; and


•	Level 3 - unobservable inputs significant to the fair value measurement.

We did not have any significant non-financial assets or liabilities measured at fair value on March 31, 2019, or December 31, 2018.

Our financial instruments include cash and equivalents, accounts receivable and payable, marketable securities held in trust and other investments, short- and long-term debt, and derivative financial instruments. The carrying values of cash and equivalents and accounts receivable and payable on the unaudited Consolidated Balance Sheet approximate their fair value. The following tables present the fair values of our other financial assets and liabilities on March 31, 2019, and December 31, 2018, and the basis for determining their fair values:



	Carrying Value			Fair Value			Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)			Significant Unobservable Inputs (Level 3)
Financial Assets (Liabilities)	March 31, 2019
Measured at fair value:
Marketable securities held in trust:
Cash and equivalents	$	6		$	6		$	—	$	6		$	—
Available-for-sale debt securities	143			143			—		143			—
Equity securities	50			50			50		—			—
Other investments	4			4			—		—			4
Cash flow hedges	(61		)	(61		)	—		(61		)	—
Measured at amortized cost:
Short- and long-term debt principal	(13,646		)	(13,704		)	—		(13,704		)	—



	December 31, 2018
Measured at fair value:
Marketable securities held in trust:
Cash and equivalents	$	29		$	29		$	23	$	6		$	—
Available-for-sale debt securities	121			121			—		121			—
Equity securities	52			52			52		—			—
Other investments	4			4			—		—			4
Cash flow hedges	(69		)	(69		)	—		(69		)	—
Measured at amortized cost:
Short- and long-term debt principal	(12,518		)	(12,346		)	—		(12,346		)	—

Our Level 1 assets include investments in publicly traded equity securities valued using quoted prices from the market exchanges. The fair value of our Level 2 assets and liabilities is determined under a market approach using valuation models that incorporate observable inputs such as interest rates, bond yields and quoted prices for similar assets. Our Level 3 assets include direct private equity investments that are measured using inputs unobservable to a marketplace participant.