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Valuation and Qualifying Accounts (Tables)

12 Months Ended

Dec. 31, 2020

SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]

Schedule Of Valuation And Qualifying Accounts

(in thousands)			Balance at Beginning of Year						Changes Charged to Statement of Income Accounts						Write Offs (net of recoveries)						Balance at End of Year
Allowance for expendable parts and supplies
For the Year Ended December 31, 2020			$	2,748					$	1,575					$	—					$	4,323
For the Year Ended December 31, 2019 (1)			14,410						2,257						(13,919)						2,748
For the Year Ended December 31, 2018			13,756						2,624						(1,970)						14,410

(1) Increase in write offs mostly related to disposal of MD-80 fleet parts in 2019.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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