Consolidated Statements of Comprehensive Income (unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 26.3	$ 35.9	$ 36.7	$ 42.0
Derivative financial instruments:
Unrealized gains (losses) arising during the period, net of tax benefit (expense) of $(3.0), $0.2, $(8.4), and $(1.5)	10.0	(0.8)	26.8	5.0
Reclassification adjustments for losses included in net income, net of tax benefit (expense) of $(0.1), $0.3, $1.2, and $0.6	0.2	1.8	4.6	2.9
Defined benefit plans:
Amortization of net actuarial losses, net of tax benefit of $—, $—, $—, and $0.1	0.1	0.0	0.2	0.1
Foreign Currency Translation [Abstract]
Reclassification adjustments for losses included in discontinued operations, net of tax benefit of $—, $—, $—, and $—	0.0	0.0	1.3	0.0
Other Comprehensive Income (Loss), Net of Tax, Total	10.3	1.0	32.9	8.0
Comprehensive income	36.6	36.9	69.6	50.0
Less: comprehensive income (loss) attributable to noncontrolling interest	0.8	4.2	7.4	(5.0)
Comprehensive income attributable to Trinity Industries, Inc.	$ 35.8	$ 32.7	$ 62.2	$ 55.0