Accumulated Other Comprehensive Loss (Details) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Comprehensive net income (loss)
Net income attributable to Trinity Industries, Inc	$ 31.9	$ 29.7	$ 86.1	$ 50.1
Other comprehensive income (loss):
Change in currency translation adjustment, net of tax benefit of $0.0			(0.1)
Change in unrealized loss on derivative financial instruments, net of tax benefit of $(2.8), $(4.3), $(2.0), and $(11.6)			(3.5)
Comprehensive net income			85.2
Trinity Stockholders' Equity [Member]
Comprehensive net income (loss)
Net income attributable to Trinity Industries, Inc	31.9	29.7	86.1	50.1
Other comprehensive income (loss):
Change in currency translation adjustment, net of tax benefit of $0.0			(0.1)
Change in unrealized loss on derivative financial instruments, net of tax benefit of $(2.8), $(4.3), $(2.0), and $(11.6)	(5.2)	(7.6)	(3.2)	(23.5)
Other changes, net of tax expense of $0.7				1.1
Comprehensive net income	$ 26.7	$ 22.1	$ 82.8	$ 27.7