Fair Value Measurements and Financial Instruments Fair Value Measurements and Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2012

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Fair Value, Assets Measured on Recurring Basis [Table Text Block]

Our assets and liabilities measured at fair value on a recurring basis at December 31, 2012 and December 31, 2011, were as follows:

			Fair Value Measurements at December 31, 2012 Using:
	Total Carrying Value at		Quoted prices in active markets		Significant other observable inputs		Significant unobservable inputs
Description	December 31, 2012		(Level 1)		(Level 2)		(Level 3)
Assets:
Assets invested for self-insurance, classified as other assets, noncurrent	$	10,758	$	10,758	$	—	$	—
Fuel derivatives, classified as other current assets	38		—		38		—
Defined benefit pension plan assets	22,957		20,463		2,494		—
Liabilities:
Fuel derivatives, classified as accrued expenses	$	24	$	—	$	24	$	—
Deferred compensation	873		—		873		—

			Fair Value Measurements at December 31, 2011 Using:
	Total Carrying Value at		Quoted prices in active markets		Significant other observable inputs		Significant unobservable inputs
Description	December 31, 2011		(Level 1)		(Level 2)		(Level 3)
Assets:
Assets invested for self-insurance, classified as other assets, noncurrent	$	13,064	$	13,064	$	—	$	—
Defined benefit pension plan assets	22,078		19,895		2,183		—
Liabilities:
Interest rate swaps, classifieds as accrued expenses	$	123	$	—	$	123	$	—
Fuel derivatives, classified as accrued expenses	108		—		108		—
Fuel derivatives, classified as other noncurrent liabilities	317		—		317		—
Deferred compensation	684		—		684		—

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

Financial instruments classified as noncurrent liabilities and their carrying values and fair values were as follows:

	December 31, 2012				December 31, 2011
	Carrying Value		Fair Value		Carrying Value		Fair Value
Revolving credit facility, noncurrent	$	24,200	$	24,200	$	20,000	$	20,000
Senior unsecured notes	30,000		29,762		30,000		29,925
Term loans, noncurrent	588		588		1,136		1,135
Total	$	54,788	$	54,550	$	51,136	$	51,060

Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]

The following tables sets forth quantitative information related to our derivatives instruments and where these amounts are recorded in our consolidated financial statements.

	As of December 31,
	2012		2011
Cash Flow Hedges - Derivatives Designated as Hedging Instruments
Interest Rate Swaps:
Liability fair value of interest rate swaps, classified as accrued expenses	$	—	$	123
Notional amount of long-term debt hedged	$	—	$	10,000
Economic Hedges - Derivatives Not Designated as Hedging Instruments
Fuel Derivatives:
Asset fair value of fuel derivatives, classified as other current assets	$	38	$	—
Liability fair value of fuel derivatives, classified as accrued expenses	$	24	$	108
Liability fair value of fuel derivatives, classified as other noncurrent liabilities	$	—	$	317
Longest remaining term, in months	12		24
Notional hedged volume, in thousands of gallons	1,250		2,500

	Year Ended December 31,
	2012			2011
Cash Flow Hedges - Derivatives Designated as Hedging Instruments
Interest Rate Swaps:
Hedge gains, recognized in other comprehensive income	$	123		$	917
Economic Hedges - Derivatives Not Designated as Hedging Instruments
Fuel Derivatives:
Change in fair value, recognized in results of operations, as a (reduction)/increase in costs and expenses, operating	$	(650	)	$	425