Leases and Aircraft Maintenance Deposits - Future Minimum Lease Payments Under Finance and Operating Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Finance Leases
2022	$ 842
2023	465
2024	215
2025	117
2026	39
2027 and thereafter	0
Total minimum lease payments	1,678
Less amount representing interest	90
Present value of minimum lease payments	1,588
Less current portion	785
Long-term portion	803
Operating Leases
Less current portion	158,631	$ 133,791
Long-term portion	1,751,351	$ 1,248,519
Total Operating and Finance Lease Obligations
2022	260,891
2023	254,687
2024	240,054
2025	219,812
2026	193,312
2027 and thereafter	1,654,849
Total minimum lease payments	2,823,605
Less amount representing interest	912,035
Present value of minimum lease payments	1,911,570
Less current portion	159,416
Finance And Operating Leases, Liability, Noncurrent	$ 1,752,154
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Long-term Debt and Lease Obligation, Including Current Maturities
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Current maturities of long-term debt and finance leases
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Long-term debt and finance leases, less current maturities
Aircraft and Spare Engine Leases
Operating Leases
2022	$ 255,121
2023	249,420
2024	236,811
2025	218,569
2026	192,309
2027 and thereafter	1,512,674
Total minimum lease payments	2,664,904
Less amount representing interest	778,639
Present value of minimum lease payments	1,886,265
Less current portion	154,946
Long-term portion	1,731,319
Property Facility Leases
Operating Leases
2022	4,771
2023	4,788
2024	3,028
2025	1,126
2026	964
2027 and thereafter	142,175
Total minimum lease payments	156,852
Less amount representing interest	133,304
Present value of minimum lease payments	23,548
Less current portion	3,529
Long-term portion	20,019
Other
Operating Leases
2022	157
2023	14
2024	0
2025	0
2026	0
2027 and thereafter	0
Total minimum lease payments	171
Less amount representing interest	2
Present value of minimum lease payments	169
Less current portion	156
Long-term portion	$ 13

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