FAIR VALUE MEASUREMENTS (TABLES)

12 Months Ended

Dec. 31, 2011

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

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



December 31, 2011	Level 1		Level 2			Total

Assets
Marketable securities
U.S. government securities	$	295.9	$	—		$	295.9
Foreign government bonds	—		25.4			25.4
Asset-back securities	—		58.0			58.0
Mortgage-back securities	—		124.9			124.9
Corporate notes and bonds	—		522.6			522.6
Municipal securities	—		11.9			11.9
Derivative instruments
Fuel hedge contracts	—		116.9			116.9

Liabilities
Derivative instruments
Fuel hedge contracts	—		(10.3		)	(10.3		)
Interest rate swap agreements	—		(28.8		)	(28.8		)



December 31, 2010	Level 1		Level 2			Total

Assets
Marketable securities
U.S. government securities	$	472.9	$	—		$	472.9
Foreign government bonds	—		41.6			41.6
Asset-back securities	—		51.7			51.7
Mortgage-back securities	—		125.5			125.5
Corporate notes and bonds	—		420.3			420.3
Municipal securities	—		6.7			6.7
Derivative instruments
Fuel hedge contracts	—		131.3			131.3

Liabilities
Derivative instruments
Interest rate swap agreements	—		(8.8		)	(8.8		)

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 as of December 31 (in millions):



	2011		2010
Carrying Amount	$	1,002.5	$	1,233.6
Fair value	1,075.8		1,285.0

- Definition

Tabular disclosure of the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments, assets, and liabilities. Such certain disclosures about the financial instruments, assets, and liabilities include: (1) the fair value of the required items together with their carrying amounts (as appropriate) and (2) the methodology and assumptions used in developing such estimates of fair value.

+ References

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-Publisher FASB

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+ Details