Assets Held for Sale (Details) - CRJ 700 - Held for sale $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2024 USD ($) aircraft	Dec. 31, 2022 aircraft	Dec. 31, 2023 USD ($)
Assets Held for Sale
Number of aircraft held-for-sale \| aircraft	14	14
Gain due to elimination of the costs to sell in other operating expenses	$ 4.2
Assets held for sale			$ 54.3

Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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