Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Oct. 17, 2018
Entity Information [Line Items]
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Registrant Name	TRINITY INDUSTRIES INC
Entity Central Index Key	0000099780
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Amendment Flag	false
Document Fiscal Year Focus	2018
Document Fiscal Period	Q3
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		146,298,614