Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Cash Flows [Abstract]
Net cost of sold lease fleet railcars owned one year or less	$ 92.0	$ 295.9	$ 350.2

Payments to Acquire Leasing Assets Net of Sold Railcars Owned One Year or Less Net Cost

No definition available.

Name:	trn_PaymentstoAcquireLeasingAssetsNetofSoldRailcarsOwnedOneYearorLessNetCost
Namespace Prefix:	trn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration