Leases Finance and Operating Lease Maturities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Finance Leases
remainder of 2019	$ 894
2020	780
2021	606
2022	578
2023	202
2024 and thereafter	0
Total minimum lease payments	3,060
Less amount representing interest	310
Present value of minimum lease payments	2,750
Less current portion	1,053
Long-term portion	1,697
Operating Leases
Less current portion	128,138	$ 0
Long-term portion	895,056	$ 0
Total Operating and Finance Lease Obligations
remainder of 2019	146,117
2020	189,105
2021	186,081
2022	177,711
2023	152,434
2024 and thereafter	481,936
Total minimum lease payments	1,333,384
Less amount representing interest	307,440
Present value of minimum lease payments	1,025,944
Less current portion	129,191
Long-term portion	896,753
Aircraft and Spare Engine
Operating Leases
remainder of 2019	142,701
2020	185,414
2021	183,572
2022	175,571
2023	151,177
2024 and thereafter	477,187
Total minimum lease payments	1,315,622
Less amount representing interest	303,429
Present value of minimum lease payments	1,012,193
Less current portion	125,429
Long-term portion	886,764
Property Facility
Operating Leases
remainder of 2019	2,088
2020	2,394
2021	1,903
2022	1,562
2023	1,055
2024 and thereafter	4,749
Total minimum lease payments	13,751
Less amount representing interest	3,658
Present value of minimum lease payments	10,093
Less current portion	2,165
Long-term portion	7,928
Other
Operating Leases
remainder of 2019	434
2020	517
2021	0
2022	0
2023	0
2024 and thereafter	0
Total minimum lease payments	951
Less amount representing interest	43
Present value of minimum lease payments	908
Less current portion	544
Long-term portion	$ 364