Railcar Leasing and Management Services Group (Details 1) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Revenues:
Total revenues	$ 1,562.8		$ 1,110.3		$ 4,508.6		$ 3,109.3
Operating profit:
Total operating profit	281.2		205.6		974.5		548.5
Selected expense information:
Depreciation					171.5		156.2
Interest:
Interest expense	48.2		45.8		141.4		141.5
Railcar Leasing and Management Services Group
Revenues:
Total revenues	203.0		150.6		870.6		454.6
Operating profit:
Total operating profit	87.0		74.0		419.7		211.3
Operating profit margin:
Total operating profit margin	42.30%		49.10%		47.70%		46.50%
Selected expense information:
Depreciation	32.4	[1]	32.8	[1]	97.1	[1]	95.8	[1]
Percent Change, Depreciation	(1.20%)	[1]			1.40%	[1]
Maintenance	17.8	[1]	16.4	[1]	58.8	[1]	53.8	[1]
Percent Change, Maintenance	8.50%	[1]			9.30%	[1]
Rent	13.1	[1]	13.3	[1]	39.7	[1]	40.0	[1]
Percent Change, Rent	(1.50%)	[1]			(0.80%)	[1]
Interest:
Interest expense	39.1	[1]	37.3	[1]	114.5	[1]	116.2	[1]
Railcar Leasing and Management Services Group | Leasing and management
Revenues:
Total revenues	158.3		150.6		469.2		435.6
Percent Change	5.10%				7.70%
Operating profit:
Total operating profit	74.4		72.4		213.8		198.2
Percentage Change	2.80%				7.90%
Operating profit margin:
Total operating profit margin	47.00%		48.10%		45.60%		45.50%
Railcar Leasing and Management Services Group | Railcars owned one year or less at the time of sale
Revenues:
Total revenues	47.4		0		411.1		19.0
Operating profit:
Total operating profit	9.6		0		115.7		3.5
Railcar Leasing and Management Services Group | Railcars owned more than one year at the time of sale
Operating profit:
Total operating profit	3.0		1.6		90.2		9.6
Rail Group
Revenues:
Total revenues	802.3		541.5		2,164.1		1,439.2
Operating profit:
Total operating profit	186.4		121.5		529.9		332.3
Intercompany | Railcar Leasing and Management Services Group
Interest:
Interest expense	0	[1]	0	[1]	0	[1]	3.8	[1]
Total
Revenues:
Total revenues	1,562.8		1,110.3		4,508.6		3,109.3
Total | Railcar Leasing and Management Services Group
Revenues:
Total revenues	205.7		150.6		880.3		454.6
Percent Change	36.60%				93.60%
Operating profit:
Total operating profit	87.0		74.0		419.7		211.3
Percentage Change	17.60%				98.60%
Interest:
Interest expense	39.1	[1]	37.3	[1]	114.5	[1]	120.0	[1]
Percent Change, Total interest expense	4.80%	[1]			(4.60%)	[1]
Total | Rail Group
Revenues:
Total revenues	$ 996.4		$ 718.5		$ 2,749.4		$ 2,012.0

[1] Depreciation, maintenance, and rent expense are components of operating profit. Amortization of deferred profit on railcars sold from the Rail Group to the Leasing Group is included in the operating profits of the Leasing Group resulting in the recognition of depreciation expense based on the Company's original manufacturing cost of the railcars. Interest expense is not a component of operating profit and includes the effect of hedges. Intercompany interest expense is eliminated in consolidation and arises from Trinity’s previous ownership of a portion of TRIP Holdings’ Senior Secured Notes, which notes were retired in full in May 2013. See Note 11 Debt.