Leases Finance and Operating Lease Maturities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Finance Leases
Remainder of 2021	$ 564
2022	725
2023	349
2024	97
2025	0
2026 and thereafter	0
Total minimum lease payments	1,735
Less amount representing interest	113
Present value of minimum lease payments	1,622
Less current portion	673
Long-term portion	949
Operating Leases
Less current portion	135,260	$ 133,791
Long-term portion	1,290,800	$ 1,248,519
Total Operating and Finance Lease Obligations
Remainder of 2021	183,360
2022	217,700
2023	208,429
2024	184,951
2025	161,471
2026 and thereafter	1,215,648
Total minimum lease payments	2,171,559
Less amount representing interest	724,013
Present value of minimum lease payments	1,447,546
Less current portion	135,933
Long-term portion	1,311,613
Other Current Liabilities \| COVID-19 Pandemic
Total Operating and Finance Lease Obligations
2022	19,900
Aircraft and Spare Engine Leases
Operating Leases
Remainder of 2021	179,092
2022	212,304
2023	204,097
2024	182,035
2025	160,411
2026 and thereafter	1,072,555
Total minimum lease payments	2,010,494
Less amount representing interest	589,617
Present value of minimum lease payments	1,420,877
Less current portion	131,744
Long-term portion	1,289,133
Property Facility Leases
Operating Leases
Remainder of 2021	3,704
2022	4,671
2023	3,983
2024	2,819
2025	1,060
2026 and thereafter	143,093
Total minimum lease payments	159,330
Less amount representing interest	134,283
Present value of minimum lease payments	25,047
Less current portion	3,516
Long-term portion	$ 21,531

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