FUEL DERIVATIVES AND RISK MANAGEMENT (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fuel Derivative Gains (Losses)
Outstanding derivative contracts	$ 0
Fuel Derivative Contracts
Changes in Derivative Assets (Liabilities)
Balance - January 1	(1,174)	$ 2,233
Non-cash Gains (Losses)	3,527	(12,206)
Contract Settlements	(2,353)	8,799
Balance - End of period		(1,174)	$ 2,233
Fuel Derivative Gains (Losses)
Non-cash Gains (Losses)	3,527	(12,206)	10,791
Cash Premiums Paid		(2,053)	(665)
Total Fuel Derivative Gains (Losses)	$ 3,527	$ (14,259)	$ 10,126

The amount of cash premiums paid during period.

No definition available.

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- Definition

The amount of non-cash gain (loss) on derivatives

+ References

No definition available.

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Topic 815
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of gain (loss) recognized in income from derivative asset (liability) after deduction of derivative liability (asset), measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount of settlements of financial instrument classified as a derivative asset (liability) after deduction of derivative liability, measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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- Definition

Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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