Consolidated Statements of Comprehensive Income (unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net income	$ 189.0us-gaap_ProfitLoss	$ 233.0us-gaap_ProfitLoss
Derivative financial instruments:
Unrealized losses arising during the period, net of tax benefit of $0.2 and $0.4	(0.3)	(1.2)
Reclassification adjustments for losses included in net income, net of tax benefit of $2.1 and $2.0	3.8	4.3
Currency translation adjustment	(3.8)	0
Defined benefit plans:
Amortization of net actuarial losses, net of tax benefit of $0.5 and $0.1	0.8	0.2
Total other comprehensive income (loss)	0.5	3.3
Comprehensive income	189.5	236.3
Less: comprehensive income attributable to noncontrolling interest	9.4	7.3
Comprehensive income attributable to Trinity Industries, Inc.	$ 180.1us-gaap_ComprehensiveIncomeNetOfTax	$ 229.0us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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