Note 10. Employee Retirement Plans Cash Flows (Details) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($)
Retirement Benefits [Abstract]
Defined Contribution Plan, Expected Future Employer Discretionary Contributions, Next Fiscal Year	$ 7.6
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 19.4

Defined Contribution Plan, Expected Future Employer Discretionary Contributions, Next Fiscal Year

No definition available.

Name:	trn_DefinedContributionPlanExpectedFutureEmployerDiscretionaryContributionsNextFiscalYear
Namespace Prefix:	trn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration