FAIR VALUE MEASUREMENTS (TABLES)

3 Months Ended

Mar. 31, 2014

Fair Value Disclosures [Abstract]

Fair Value, Measurement Inputs, Disclosure [Table Text Block]

Fair values of financial instruments on the consolidated balance sheet (in millions):

March 31, 2014	Level 1		Level 2			Total
Assets
Marketable securities
U.S. government and agency securities	$	283	$	—		$	283
Foreign government bonds	—		18			18
Asset-back securities	—		158			158
Mortgage-back securities	—		146			146
Corporate notes and bonds	—		700			700
Municipal securities	—		25			25
Derivative instruments
Call options	—		15			15
Liabilities
Derivative instruments
Fuel hedge contracts	—		(2		)	(2		)
Interest rate swap agreements	—		(18		)	(18		)

December 31, 2013	Level 1		Level 2			Total
Assets
Marketable securities
U.S. government and agency securities	$	294	$	—		$	294
Foreign government bonds	—		11			11
Asset-back securities	—		146			146
Mortgage-back securities	—		143			143
Corporate notes and bonds	—		630			630
Municipal securities	—		26			26
Derivative instruments
Call options	—		16			16
Liabilities
Derivative instruments
Fuel hedge contracts	—		—			—
Interest rate swap agreements	—		(17		)	(17		)

Fair Value, by Balance Sheet Grouping [Table Text Block]

Fixed-rate debt that is not carried at fair value on the consolidated balance sheet and the estimated fair value of long-term fixed-rate debt (in millions):

	March 31, 2014		December 31, 2013
Carrying amount	$	678	$	703
Fair value	733		762