Asset Impairments and Assets Held for Sale (Details) $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) AircraftEngines	Dec. 31, 2022 USD ($) AircraftEngines	Dec. 31, 2021 USD ($)
Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property	$ 130.9	$ 121.2	$ 99.4
Asset Impairment Charges	1.5	48.9	2.4
Assets Held-for-sale, Long Lived, Fair Value Disclosure	0.8	40.0
Net gain (loss) on asset dispositions	130.3	77.9	105.9
Rail North America [Member]
Asset Impairment Charges	0.0	0.0	2.4
Assets Held-for-sale, Long Lived, Fair Value Disclosure	0.8	1.2
Net gain (loss) on asset dispositions	120.5	119.7	94.3
Rail International [Member]
Asset Impairment Charges	0.3	14.6	0.0
Charge for anticipated liquidation of translation adjustment	1.2
Assets Held-for-sale, Long Lived, Fair Value Disclosure	0.0	13.7
Net gain (loss) on asset dispositions	7.0	(11.2)	2.7
Gain on disposition of Rail Russia	0.3
Portfolio Management [Member]
Asset Impairment Charges	1.2	34.3	0.0
Assets Held-for-sale, Long Lived, Fair Value Disclosure	$ 0.0	$ 25.1
Number of Specialized Gas Vessels Sold | AircraftEngines	3	2
Net gain (loss) on asset dispositions	$ 2.2	$ (31.1)	$ 8.0
Portfolio Management [Member] | Specialized Gas Vessels [Member]
Gains on sales of assets	$ 4.0