Railcar Leasing and Management Services Group - Future operating lease obligations and future contractual minimum rental revenues (Details) $ in Millions	Jun. 30, 2023 USD ($)
Future operating lease obligations
Remaining six months of 2023	$ 10.4
2024	16.1
2025	14.3
2026	13.4
2027	12.7
Thereafter	61.5
Lessee, Operating Lease, Liability, to be Paid, Total	128.4
Railcar Leasing and Management Services Group [Member]
Future operating lease obligations
Remaining six months of 2023	5.4
2024	7.1
2025	6.2
2026	5.8
2027	5.3
Thereafter	3.7
Lessee, Operating Lease, Liability, to be Paid, Total	33.5
Future contractual minimum rental revenues
Remaining six months of 2023	340.7	[1]
2024	588.8	[1]
2025	475.3	[1]
2026	360.1	[1]
2027	261.4	[1]
Thereafter	400.0	[1]
Total	2,426.3	[1]
Railcar Leasing and Management Services Group [Member] | Railroad Transportation Equipment
Future operating lease obligations
Remaining six months of 2023	5.3
2024	7.0
2025	6.2
2026	5.8
2027	5.3
Thereafter	3.7
Lessee, Operating Lease, Liability, to be Paid, Total	33.3
Railcar Leasing and Management Services Group [Member] | Building [Member]
Future operating lease obligations
Lessee, Operating Lease, Liability, to be Paid, Total	0.2
Railcar Leasing and Management Services Group [Member] | Property Lease Guarantee [Member]
Future contractual minimum rental revenues
Guarantor Obligations, Maximum Exposure, Undiscounted	1.1
Railcar Leasing and Management Services Group [Member] | Operating leases
Future contractual minimum rental revenues
Remaining six months of 2023	5.1
2024	6.1
2025	4.2
2026	2.5
2027	0.8
Thereafter	0.2
Total	$ 18.9

[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.