Railcar Leasing and Management Services Group - Future operating lease obligations and future contractual minimum rental revenues (Details) $ in Millions	Mar. 31, 2022 USD ($)
Future operating lease obligations
Remaining nine months of 2022	$ 14.9
2023	17.7
2024	13.3
2025	10.8
2026	10.1
Thereafter	64.3
Lessee, Operating Lease, Liability, to be Paid, Total	131.1
Railcar Leasing and Management Services Group [Member]
Future operating lease obligations
Remaining nine months of 2022	9.2
2023	10.5
2024	7.0
2025	5.2
2026	4.9
Thereafter	7.6
Lessee, Operating Lease, Liability, to be Paid, Total	44.4
Future contractual minimum rental revenues
Remaining nine months of 2022	421.4	[1]
2023	436.7	[1]
2024	330.0	[1]
2025	237.3	[1]
2026	157.0	[1]
Thereafter	283.2	[1]
Total	1,865.6	[1]
Railcar Leasing and Management Services Group [Member] | Building [Member]
Future operating lease obligations
Lessee, Operating Lease, Liability, to be Paid, Total	0.3
Railcar Leasing and Management Services Group [Member] | Railroad Transportation Equipment
Future operating lease obligations
Remaining nine months of 2022	9.1
2023	10.4
2024	6.9
2025	5.2
2026	4.9
Thereafter	7.6
Lessee, Operating Lease, Liability, to be Paid, Total	44.1
Railcar Leasing and Management Services Group [Member] | Property Lease Guarantee [Member]
Future contractual minimum rental revenues
Guarantor Obligations, Maximum Exposure, Undiscounted	1.6
Railcar Leasing and Management Services Group [Member] | Operating leases
Future contractual minimum rental revenues
Remaining nine months of 2022	6.2
2023	5.4
2024	2.8
2025	1.9
2026	1.2
Thereafter	0.1
Total	$ 17.6

[1] Total contractual minimum rental revenues on operating leases relates to our wholly-owned and partially-owned subsidiaries and sub-lease rental revenues associated with the Leasing Group's operating lease obligations.