Property, Plant, and Equipment (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Components of property, plant, and equipment
Property, plant and equipment of TRIP Holdings	$ 5,479.3	$ 5,407.9
Less accumulated depreciation, including TRIP Holdings of $128.7 and $122.7	(1,262.0)	(1,228.4)
Property plant and equipment net before adjustment to Net deferred profit	4,751.7	4,711.0
Property, plant and equipment, total	4,217.3	4,179.5
TRIP Holdings [Member]
Components of property, plant, and equipment
Property, plant and equipment of TRIP Holdings	1,271.4	1,257.7
Less accumulated depreciation, including TRIP Holdings of $128.7 and $122.7	(128.7)	(122.7)
Manufacturing/Corporate [Member]
Components of property, plant, and equipment
Property, plant and equipment of TRIP Holdings	1,235.5	1,242.8
Less accumulated depreciation, including TRIP Holdings of $128.7 and $122.7	(735.1)	(732.8)
Property plant and equipment net before adjustment to Net deferred profit	500.4	510.0
Property, plant and equipment, total	500.4	510.0
Leasing Group [Member] | TRIP Holdings [Member]
Components of property, plant, and equipment
Less accumulated depreciation, including TRIP Holdings of $128.7 and $122.7	(128.7)	(122.7)
Property plant and equipment net before adjustment to Net deferred profit	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
Leasing Group [Member] | Wholly Owned Subsidiaries [Member]
Components of property, plant, and equipment
Property, plant and equipment of TRIP Holdings	3,506.8	3,438.9
Less accumulated depreciation, including TRIP Holdings of $128.7 and $122.7	(398.2)	(372.9)
Property plant and equipment net before adjustment to Net deferred profit	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
Land [Member] | Manufacturing/Corporate [Member]
Components of property, plant, and equipment
Property, plant and equipment of TRIP Holdings	41.6	41.6
Buildings and improvements [Member] | Manufacturing/Corporate [Member]
Components of property, plant, and equipment
Property, plant and equipment of TRIP Holdings	430.2	429.7
Machinery and other [Member] | Manufacturing/Corporate [Member]
Components of property, plant, and equipment
Property, plant and equipment of TRIP Holdings	746.4	758.7
Machinery and other [Member] | Leasing Group [Member] | Wholly Owned Subsidiaries [Member]
Components of property, plant, and equipment
Property, plant and equipment of TRIP Holdings	9.6	9.6
Construction in progress [Member] | Manufacturing/Corporate [Member]
Components of property, plant, and equipment
Property, plant and equipment of TRIP Holdings	17.3	12.8
Equipment on lease [Member] | Leasing Group [Member] | TRIP Holdings [Member]
Components of property, plant, and equipment
Property, plant and equipment of TRIP Holdings	1,271.4	1,257.7
Equipment on lease [Member] | Leasing Group [Member] | Wholly Owned Subsidiaries [Member]
Components of property, plant, and equipment
Property, plant and equipment of TRIP Holdings	$ 3,497.2	$ 3,429.3