Railcar Leasing and Management Services Group (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Consolidating Financial Information
Cash and cash equivalents	$ 304.8	$ 351.1
Property, plant, and equipment, net	4,751.7	4,711.0
Net deferred profit on railcars sold to the Leasing Group	(534.4)	(531.5)
Property, plant and equipment, total	4,217.3	4,179.5
Restricted cash of TRIP Holdings	224.0	240.3
Debt:
Recourse	558.0	557.5
Less: unamortized discount	(96.8)	(99.8)
Total Recourse Debt	461.2	457.7
Non-recourse	2,575.1	2,626.0
Less: non-recourse debt owned by Trinity	(108.8)	(108.8)
Total debt	2,927.5	2,974.9
Net deferred tax liabilities	465.5	434.7
TRIP Holdings [Member]
Consolidating Financial Information
Restricted cash of TRIP Holdings	59.2	74.6
Debt:
Less: unamortized discount	(96.8)	(99.8)
Manufacturing/Corporate [Member]
Consolidating Financial Information
Cash and cash equivalents	301.1	347.9
Property, plant, and equipment, net	500.4	510.0
Property, plant and equipment, total	500.4	510.0
Debt:
Recourse	456.1	454.2
Less: unamortized discount	(96.8)	(99.8)
Total Recourse Debt	359.3	354.4
Total debt	359.3	354.4
Net deferred tax liabilities	(97.0)	(152.4)
Leasing Group [Member] | Wholly Owned Subsidiaries [Member]
Consolidating Financial Information
Cash and cash equivalents	3.7	3.2
Property, plant, and equipment, net	3,108.6	3,066.0
Net deferred profit on railcars sold to the Leasing Group	(348.0)	(344.5)
Property, plant and equipment, total	2,760.6	2,721.5
Restricted cash of TRIP Holdings	164.8	165.7
Debt:
Recourse	101.9	103.3
Total Recourse Debt	101.9	103.3
Non-recourse	1,575.5	1,616.0
Total debt	1,677.4	1,719.3
Net deferred tax liabilities	557.9	582.4
Leasing Group [Member] | TRIP Holdings [Member]
Consolidating Financial Information
Property, plant, and equipment, net	1,142.7	1,135.0
Net deferred profit on railcars sold to the Leasing Group	(186.4)	(187.0)
Property, plant and equipment, total	956.3	948.0
Restricted cash of TRIP Holdings	59.2	74.6
Debt:
Non-recourse	999.6	1,010.0
Less: non-recourse debt owned by Trinity	(108.8)	(108.8)
Total debt	890.8	901.2
Net deferred tax liabilities	$ 4.6	$ 4.7