Railcar Leasing and Management Services Group - Future contractual minimum rental revenues on leases (Details) - Railcar Leasing and Management Services Group $ in Millions	Mar. 31, 2019 USD ($)
Future contractual minimum rental revenue
Operating Leases, Future Minimum Payments Receivable, Remainder of Fiscal Year	$ 430.9
Operating Leases, Future Minimum Payments Receivable, in Two Years	478.3
Operating Leases, Future Minimum Payments Receivable, in Three Years	358.9
Operating Leases, Future Minimum Payments Receivable, in Four Years	267.2
Operating Leases, Future Minimum Payments Receivable, in Five Years	174.4
Thereafter	312.8
Total	2,022.5
Railroad Transportation Equipment
Future contractual minimum rental revenue
Operating Leases, Future Minimum Payments Receivable, Remainder of Fiscal Year	423.0
Operating Leases, Future Minimum Payments Receivable, in Two Years	471.0
Operating Leases, Future Minimum Payments Receivable, in Three Years	353.5
Operating Leases, Future Minimum Payments Receivable, in Four Years	263.5
Operating Leases, Future Minimum Payments Receivable, in Five Years	172.9
Thereafter	312.4
Total	$ 1,996.3