Note 16. Selected Quarterly Financial Data (Details) - USD ($)	3 Months Ended																12 Months Ended
	Dec. 31, 2021		Sep. 30, 2021		Jun. 30, 2021		Mar. 31, 2021		Dec. 31, 2020		Sep. 30, 2020		Jun. 30, 2020		Mar. 31, 2020		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues	$ 472,200,000		$ 419,800,000		$ 293,300,000		$ 330,700,000		$ 359,700,000		$ 396,800,000		$ 439,900,000		$ 553,300,000		$ 1,516,000,000	$ 1,749,700,000	$ 2,752,400,000
Cost of revenues:	375,700,000		337,400,000		202,100,000		246,300,000		254,400,000		288,900,000		344,500,000		439,600,000		1,161,500,000	1,327,400,000	2,178,400,000
Selling, engineering, and administrative expenses:	42,900,000		45,800,000		46,200,000		44,700,000		47,500,000		42,900,000		48,600,000		50,600,000		179,600,000	189,600,000	217,000,000.0
Gains on dispositions of property:	13,000,000.0		41,600,000		12,100,000		11,500,000		100,000		3,700,000		6,600,000		9,600,000		78,200,000	20,000,000.0	54,400,000
Impairment of long-lived assets									27,000,000.0		0		369,400,000	[1]	0		0	396,400,000	0
Restructuring activities, net	(2,600,000)		(100,000)		(700,000)		(300,000)		500,000		4,700,000		300,000		5,400,000		(3,700,000)	10,900,000	14,600,000
Total operating profit (loss)	69,200,000		78,300,000		57,800,000		51,500,000		30,400,000		64,000,000.0		(316,300,000)		67,300,000		256,800,000	(154,600,000)	396,800,000
Nonoperating Income (Expense)	41,100,000		44,500,000		63,500,000		52,500,000		205,900,000	[2]	53,700,000		52,300,000		58,100,000		201,600,000	370,000,000.0	215,600,000
Income (loss) from continuing operations before income taxes	28,100,000		33,800,000		(5,700,000)		(1,000,000.0)		(175,500,000)		10,300,000		(368,600,000)		9,200,000		55,200,000	(524,600,000)	181,200,000
Provision (benefit) for income taxes:	6,500,000		8,300,000		(2,900,000)		4,000,000.0		(42,300,000)		(8,700,000)		(74,000,000.0)		(149,100,000)		15,900,000	(274,100,000)	58,800,000
Income (loss) from continuing operations	21,600,000		25,500,000		(2,800,000)		(5,000,000.0)		(133,200,000)		19,000,000.0		(294,600,000)		158,300,000		39,300,000	(250,500,000)	122,400,000
Gain on sale of discontinued operations, net of provision for income taxes of $51.9, $—, and $—	131,400,000		0		0		0										131,400,000	0	0
Income from discontinued operations, net of provision for income taxes of $3.5, $5.5, and $1.7	(13,200,000)		10,400,000		7,600,000		6,300,000		6,600,000		6,900,000		6,800,000		4,000,000.0		11,100,000	24,300,000	13,700,000
Net income (loss)	139,800,000		35,900,000		4,800,000		1,300,000		(126,600,000)		25,900,000		(287,800,000)		162,300,000		181,800,000	(226,200,000)	136,100,000
Net loss attributable to noncontrolling interest	5,800,000		3,900,000		(7,900,000)		(2,000,000.0)		600,000		800,000		(80,900,000)		600,000		(200,000)	(78,900,000)	(1,500,000)
Net income (loss) attributable to Trinity Industries, Inc.	$ 134,000,000.0		$ 32,000,000.0		$ 12,700,000		$ 3,300,000		$ (127,200,000)		$ 25,100,000		$ (206,900,000)		$ 161,700,000		$ 182,000,000.0	$ (147,300,000)	$ 137,600,000
Income (loss) from continuing operations	$ 0.16	[3]	$ 0.22	[3]	$ 0.05	[3]	$ (0.03)	[3]	$ (1.19)	[3]	$ 0.15	[3]	$ (1.82)	[3]	$ 1.32	[3]	$ 0.39	$ (1.48)	$ 0.98
Income from discontinued operations	1.23	[3]	0.11	[3]	0.07	[3]	0.06	[3]	0.06	[3]	0.06	[3]	0.06	[3]	0.04	[3]	1.40	0.21	0.11
Basic net income (loss) attributable to Trinity Industries, Inc.	1.39	[3]	0.33	[3]	0.12	[3]	0.03	[3]	(1.13)	[3]	0.21	[3]	(1.76)	[3]	1.36	[3]	1.79	(1.27)	1.09
Income (loss) from continuing operations	0.16	[3]	0.22	[3]	0.05	[3]	(0.03)	[3]	(1.19)	[3]	0.15	[3]	(1.82)	[3]	1.30	[3]	0.38	(1.48)	0.96
Income from discontinued operations	1.21	[3]	0.11	[3]	0.07	[3]	0.06	[3]	0.06	[3]	0.06	[3]	0.06	[3]	0.03	[3]	1.37	0.21	0.11
Diluted net income (loss) attributable to Trinity Industries, Inc.	$ 1.37	[3]	$ 0.33	[3]	$ 0.12	[3]	$ 0.03	[3]	$ (1.13)	[3]	$ 0.21	[3]	$ (1.76)	[3]	$ 1.33	[3]	$ 1.75	$ (1.27)	$ 1.07
Manufacturing [Member]
Revenues	$ 291,200,000		$ 234,500,000		$ 108,300,000		$ 147,400,000		$ 170,600,000		$ 213,100,000		$ 247,300,000		$ 317,200,000		$ 781,400,000	$ 948,200,000	$ 1,636,100,000
Cost of revenues:	281,900,000		238,800,000		99,600,000		149,600,000		164,900,000		202,500,000		241,600,000		301,000,000.0		769,900,000	910,000,000.0	1,462,200,000
Selling, engineering, and administrative expenses:																	32,500,000	38,600,000	60,100,000
Leasing [Member]
Revenues	181,000,000.0		185,300,000		185,000,000.0		183,300,000		189,100,000		183,700,000		192,600,000		236,100,000		734,600,000	801,500,000	1,116,300,000
Cost of revenues:	$ 93,800,000		$ 98,600,000		$ 102,500,000		$ 96,700,000		$ 89,500,000		$ 86,400,000		$ 102,900,000		$ 138,600,000		391,600,000	417,400,000	716,200,000
Selling, engineering, and administrative expenses:																	$ 50,600,000	$ 51,300,000	$ 49,500,000

[1] Impairment of long-lived assets during the three months ended June 30, 2020 relates to our small cube covered hopper railcars. See Note 11 for further information.

[2] Other expense during the three months ended December 31, 2020 includes $151.5 million related to the settlement of our Pension Plan. See Note 10 for further information.

[3] The sum of the quarters may not necessarily be equal to the full year net income per common share amount.