Summary of Significant Accounting Policies Lessor Accounting (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022		Jun. 30, 2021
Lessor, Lease, Description [Line Items]
Lessor, Operating Lease, Renewal Term		5 years		5 years
Direct Financing Lease, Revenue		$ 0.0		$ 0.0
Operating lease revenues		169.7	$ 165.0	333.3		$ 328.0
Variable operating lease revenues		18.1	12.5	31.3		25.9
Interest income on sales-type lease receivables		0.2	0.0	0.3		0.0
Profit recognized at sales-type lease commencement (1)		0.0	$ 0.0	1.3	[1]	$ 0.0
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Remainder of Fiscal Year		0.7		0.7
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Two		1.1		1.1
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Three		1.1		1.1
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Four		1.1		1.1
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, Year Five		1.1		1.1
Sales-Type and Direct Financing Leases, Lease Receivable, to be Received, after Year Five		11.0		11.0
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received		16.1		16.1
Less: Unearned interest income		(5.3)		(5.3)
Net investment in sales-type leases (1)	[2]	10.8		10.8
Railcar Leasing and Management Services Group [Member]
Lessor, Lease, Description [Line Items]
Remaining six months of 2022	[3]	295.5		295.5
2023	[3]	474.3		474.3
2024	[3]	361.7		361.7
2025	[3]	263.7		263.7
2026	[3]	180.5		180.5
Thereafter	[3]	304.2		304.2
Total	[3]	$ 1,879.9		$ 1,879.9
Minimum | Railcar Leasing and Management Services Group [Member]
Lessor, Lease, Description [Line Items]
Lessor, Operating Lease, Term of Contract		1 year		1 year
Maximum | Railcar Leasing and Management Services Group [Member]
Lessor, Lease, Description [Line Items]
Lessor, Operating Lease, Term of Contract		10 years		10 years

[1] Included in gains on dispositions of property – lease portfolio sales on our Consolidated Statements of Operations.

[2] Included in other assets in our Consolidated Balance Sheets.

[3] 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.