Railcar Leasing and Management Services Group - Future contractual minimum rental revenues on leases (Details) - Railcar Leasing and Management Services Group $ in Millions	Jun. 30, 2019 USD ($)
Future contractual minimum rental revenue
Operating Leases, Future Minimum Payments Receivable, Remainder of Fiscal Year	$ 295.6
Operating Leases, Future Minimum Payments Receivable, in Two Years	504.3
Operating Leases, Future Minimum Payments Receivable, in Three Years	390.1
Operating Leases, Future Minimum Payments Receivable, in Four Years	293.8
Operating Leases, Future Minimum Payments Receivable, in Five Years	198.6
Thereafter	355.9
Total	2,038.3
Railroad Transportation Equipment
Future contractual minimum rental revenue
Operating Leases, Future Minimum Payments Receivable, Remainder of Fiscal Year	290.5
Operating Leases, Future Minimum Payments Receivable, in Two Years	496.9
Operating Leases, Future Minimum Payments Receivable, in Three Years	384.6
Operating Leases, Future Minimum Payments Receivable, in Four Years	290.0
Operating Leases, Future Minimum Payments Receivable, in Five Years	197.1
Thereafter	355.4
Total	$ 2,014.5