Special Charges (Credits) (Details) - JetBlue Merger Agreement $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Jul. 28, 2022 installment
Unusual or Infrequent Item, or Both [Line Items]
Legal, advisory and other fees	$ 0.4	$ (13.1)	$ (27.9)	$ (20.4)
Retention award payments number of installments \| installment					2
Retention award recorded		$ 6.9	$ 8.0	$ 13.6

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479405/805-10-25-23

Name:	us-gaap_BusinessCombinationAcquisitionRelatedCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration