Railcar Leasing and Management Services Group - Future contractual minimum rental revenues on leases (Details) - Railcar Leasing and Management Services Group $ in Millions	Mar. 31, 2020 USD ($)
Future contractual minimum rental revenue
Operating Leases, Future Minimum Payments Receivable, Remainder of Fiscal Year	$ 446.5
Operating Leases, Future Minimum Payments Receivable, in Two Years	482.1
Operating Leases, Future Minimum Payments Receivable, in Three Years	376.3
Operating Leases, Future Minimum Payments Receivable, in Four Years	268.8
Operating Leases, Future Minimum Payments Receivable, in Five Years	183.7
Thereafter	330.8
Total	2,088.2
Railroad Transportation Equipment
Future contractual minimum rental revenue
Operating Leases, Future Minimum Payments Receivable, Remainder of Fiscal Year	440.7
Operating Leases, Future Minimum Payments Receivable, in Two Years	475.9
Operating Leases, Future Minimum Payments Receivable, in Three Years	371.7
Operating Leases, Future Minimum Payments Receivable, in Four Years	266.6
Operating Leases, Future Minimum Payments Receivable, in Five Years	183.2
Thereafter	330.5
Total	$ 2,068.6