Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 67.5	$ 31.6	$ 119.8	$ 57.2
Unrealized loss on derivative financial instruments:
Unrealized gain (loss) arising during the period	0.3	(12.5)	3.0	1.8
Reclassification adjustments for losses included in net income	2.2	0.9	4.5	1.7
Currency translation adjustment - reclassification adjustment for loss included in net income	1.1	(0.1)	1.1	(0.1)
Funded status of pension liability - amortization of actuarial loss	0.8		1.7
Other comprehensive income (loss), before tax	4.4	(11.7)	10.3	3.4
Income tax expense (benefit) related to components of other comprehensive income (loss)	1.6	(4.3)	4.0	1.1
Other comprehensive income (loss), net of tax	2.8	(7.4)	6.3	2.3
Comprehensive income	70.3	24.2	126.1	59.5
Less: comprehensive income (loss) attributable to noncontrolling interest	(0.1)	(0.3)	(0.2)	3.4
Comprehensive income attributable to Trinity Industries, Inc.	$ 70.4	$ 24.5	$ 126.3	$ 56.1