Revenue from Contract with Customer Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenue from Contracts with Customers [Line Items]
Railcar Manufacturing Revenue	$ 80,004	$ 48,872	$ 135,434	$ 101,643
Sales Revenue, Components Manufacturing	9,436	6,215	18,147	14,170
Sales Revenue, Goods, Net	89,440	55,087	153,581	115,813
Operating Leases, Income Statement, Lease Revenue	34,804	33,717	68,925	67,552
Revenue not subject to ASC 606	34,804	33,717	68,925	67,552
Revenue, Net	146,528	109,020	262,766	223,701
Sales Revenue, Services, Net	22,284	20,216	40,260	40,336
Contract with Customer	$ 111,724	$ 75,303	$ 193,841	$ 156,149