Lease Accounting (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
Operating lease costs	$ 32,900,000	$ 41,400,000	$ 13,600,000
Mileage credits	25,100,000	22,500,000	22,400,000
Acquired fixed assets, useful life	0	$ 0	$ (671,000)
Marine transportation
Lessor, Lease, Description [Line Items]
Expected undiscounted cash flows, year one	$ 29,600,000