Fair Value Measurements and Derivatives - Effects of derivatives designated as cash flow hedges (Details) - Cash Flow Hedging - USD ($)
$ in Thousands |
12 Months Ended |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Amount of Gain (Loss) Recognized in Other Comprehensive Income |
$ (123,015)
|
$ (161,214)
|
|
| Amount of Gain (Loss) Recognized in Other Comprehensive Income (before ASU adoption) |
|
|
$ 304,684
|
| Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income |
8,898
|
30,096
|
|
| Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (before ASU adoption) |
|
|
(36,795)
|
| Fuel |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income |
14,093
|
34,410
|
|
| Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (before ASU adoption) |
|
|
(29,721)
|
| Depreciation and amortization |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income |
(3,062)
|
(3,463)
|
|
| Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (before ASU adoption) |
|
|
(4,077)
|
| Interest expense, net |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income |
(2,133)
|
(851)
|
|
| Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income (before ASU adoption) |
|
|
(2,997)
|
| Fuel contracts |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Amount of Gain (Loss) Recognized in Other Comprehensive Income |
46,154
|
(52,949)
|
|
| Amount of Gain (Loss) Recognized in Other Comprehensive Income (before ASU adoption) |
|
|
50,263
|
| Fuel contracts | Fuel |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income |
14,093
|
34,410
|
|
| Foreign currency contracts |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Amount of Gain (Loss) Recognized in Other Comprehensive Income |
(163,197)
|
(108,911)
|
|
| Amount of Gain (Loss) Recognized in Other Comprehensive Income (before ASU adoption) |
|
|
254,070
|
| Foreign currency contracts | Depreciation and amortization |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income |
(3,062)
|
(3,463)
|
|
| Interest rate contracts |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Amount of Gain (Loss) Recognized in Other Comprehensive Income |
(5,972)
|
646
|
|
| Amount of Gain (Loss) Recognized in Other Comprehensive Income (before ASU adoption) |
|
|
$ 351
|
| Interest rate contracts | Interest expense, net |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income |
$ (2,133)
|
$ (851)
|
|