Comprehensive Income 1 (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Amounts included in AOCL
Balance at December 31, 2010			$ (3,095)
Amounts reclassified into earnings, net of taxes			848	4,310
Change in fair value			819	(7,354)
Balance at June 30, 2011	(1,428)		(1,428)
Interest Rate Swap [Member]
Amounts included in AOCL
Balance at December 31, 2010			(6,026)
Amounts reclassified into earnings, net of taxes	985	1,431	2,142	2,869
Change in fair value	(1,655)	(3,080)	(1,614)	(5,435)
Balance at June 30, 2011	(5,498)		(5,498)
Fuel Hedges [Member]
Amounts included in AOCL
Balance at December 31, 2010			2,931
Amounts reclassified into earnings, net of taxes	(792)	257	(1,294)	1,441
Change in fair value	(449)	(1,269)	2,433	(1,919)
Balance at June 30, 2011	$ 4,070		$ 4,070

Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ References+ Details

Net of tax effect of the reclassification adjustment for accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges included in accumulated comprehensive income that was realized in net income during the period.

+ References

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-Name Statement of Financial Accounting Standard (FAS)
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6522872

+ Details

- Definition

Change in accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges, net of tax effect. The after tax effect change includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ References

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-Name Accounting Standards Codification
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+ Details