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Changes in Operations U.K./Europe Optimization Restructuring Reserve Rollforward (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		15 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019
Restructuring Cost and Reserve [Line Items]
Restructuring and related costs incurred	$ 7,561	$ 9,362	$ 15,195	$ 9,645
U.K. Operations Optimization [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and related liabilities - beginning balance			5,076
Restructuring and related costs incurred	6,783		12,279		$ 27,263
Cash payments			(10,439)
Non-cash settlements			0
Restructuring and related liabilities - ending balance	6,916		6,916		6,916
Rationalization of locomotive and railcar fleet [Member] \| U.K. Operations Optimization [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and related liabilities - beginning balance			4,094
Restructuring and related costs incurred	0		0		6,301
Cash payments			(610)
Non-cash settlements			0
Restructuring and related liabilities - ending balance	3,484		3,484		3,484
Management restructuring [Member] \| U.K. Operations Optimization [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and related liabilities - beginning balance			982
Restructuring and related costs incurred	5,058		9,141		13,781
Cash payments			(6,691)
Non-cash settlements			0
Restructuring and related liabilities - ending balance	3,432		3,432		3,432
Productivity and automation investments [Member] \| U.K. Operations Optimization [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and related liabilities - beginning balance			0
Restructuring and related costs incurred	1,725		3,138		7,181
Cash payments			(3,138)
Non-cash settlements			0
Restructuring and related liabilities - ending balance	$ 0		$ 0		$ 0