Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2021

Fair Value Disclosures [Abstract]

Schedule of Fair Values of Financial Instruments and Nonfinancial Assets and Liabilities Measured at the Reporting Date

The fair values of these financial instruments are summarized as follows:

			Fair Value Measurements at Reporting Date Using
Description	At June 30, 2021		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Fuel hedge contracts	$	4,802	$	-	$	4,802	$	-

			Fair Value Measurements at Reporting Date Using
Description	At December 31, 2020		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Fuel hedge contracts	$	1,739	$	-	$	1,739	$	-

Schedule of Fair Value of Fuel Hedge Contracts Balance Sheet Location

The fair value of the fuel hedge contracts outstanding as of June 30, 2021 and December 31, 2020 is as follows:

		Fair Value at
		June 30,		December 31,
	Balance Sheet Location	2021		2020
Asset derivatives:
Derivatives designated as hedging instruments
Fuel hedge contracts	Prepaid expenses and other current assets	$	4,802	$	1,739

Changes in Components of Accumulated Other Comprehensive Income (Loss)

Changes in the components of the accumulated balances of other comprehensive income (loss) are as follows:

	Three Months Ended					Six Months Ended
	June 30,					June 30,
	2021			2020		2021			2020
Derivatives:
Reclassification of derivative (gains) losses to earnings—net of tax		(1,878	)		2,490		(3,404	)		3,828
Change in fair value of derivatives—net of tax		2,282			950		5,694			(7,514	)
Net change in cash flow derivative hedges—net of tax	$	404		$	3,440	$	2,290		$	(3,686	)

Adjustments Reclassified from Accumulated Balances Other Comprehensive Income (Loss) to Earnings

Adjustments reclassified from accumulated balances of other comprehensive income (loss) to earnings are as follows:

		Three Months Ended					Six Months Ended
		June 30,					June 30,
	Statement of Operations Location	2021			2020		2021			2020
Derivatives:
Fuel hedge contracts	Costs of contract revenues	$	(2,513	)	$	3,340		(4,554	)		5,132
	Income tax (provision) benefit		(635	)		850		(1,150	)		1,304
		$	(1,878	)	$	2,490	$	(3,404	)	$	3,828