Fair Value of Financial Instruments

9 Months Ended

Sep. 30, 2011

Fair Value of Financial Instruments and Fair Value Measurements [Abstract]

FAIR VALUE OF FINANCIAL INSTRUMENTS

4. FAIR VALUE OF FINANCIAL INSTRUMENTS

The Company’s financial instruments consist primarily of cash and equivalents, trade receivables, restricted assets, trade payables, debt instruments, interest rate swaps and fuel hedges. As of September 30, 2011 and December 31, 2010, the carrying values of cash and equivalents, trade receivables, restricted assets, and trade payables are considered to be representative of their respective fair values. The carrying values of the Company’s debt instruments, excluding certain notes as listed in the table below, approximate their fair values as of September 30, 2011 and December 31, 2010, based on current borrowing rates for similar types of borrowing arrangements. The carrying values and fair values of the Company’s debt instruments where the carrying values do not approximate their fair values as of September 30, 2011 and December 31, 2010, are as follows:

	Carrying Value at				Fair Value* at
	September 30,		December 31,		September 30,		December 31,
	2011		2010		2011		2010
6.22% Senior Notes due 2015	$	175,000	$	175,000	$	200,517	$	198,300
3.30% Senior Notes due 2016	$	100,000	$	—	$	101,890	$	—
4.00% Senior Notes due 2018	$	50,000	$	—	$	53,386	$	—
5.25% Senior Notes due 2019	$	175,000	$	175,000	$	198,905	$	191,316
4.64% Senior Notes due 2021	$	100,000	$	—	$	107,007	$	—

* Fair value based on quotes of bonds with similar ratings in similar industries

For details on the fair value of the Company’s interest rate swaps and fuel hedges, refer to Note 12.