Partially-Owned Leasing Subsidiaries - Narrative (Details) $ in Millions	3 Months Ended	21 Months Ended
Mar. 31, 2023 USD ($) board_member subsidiary	Mar. 31, 2023 USD ($) board_member
Signal Rail Holdings LLC
Noncontrolling Interest [Line Items]
Equity Method Investment, JV Majority Ownership Percentage	87.10%	87.10%
Equity Method Investment, Ownership Percentage	12.90%	12.90%
Equity Method Investment, Aggregate Future Estimated Investment of Railcars	$ 1,000.0	$ 1,000.0
Proceeds from Sales of Business, Affiliate and Productive Assets		598.6
Equity Method Investments	21.2	21.2
Partially-owned subsidiaries
Noncontrolling Interest [Line Items]
Parent Company Guarantees	$ 0.0	$ 0.0
Railcar Leasing and Management Services Group [Member] \| Partially-owned subsidiaries
Noncontrolling Interest [Line Items]
Number of Subsidiaries \| subsidiary	2
Number of Board Members \| board_member	7	7
Number of Board Members of Subsidiary, Designated by Parent \| board_member	2	2
Partially-owned subsidiaries \| Railcar Leasing and Management Services Group [Member]
Noncontrolling Interest [Line Items]
Carrying Value of Investment In Partially-Owned Consolidated Subsidiary	$ 135.3	$ 135.3
Noncontrolling Interest, Ownership Percentage by Parent	38.00%	38.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	62.00%	62.00%

Carrying Value of Investment In Partially-Owned Consolidated Subsidiary

No definition available.

Name:	trn_CarryingValueOfInvestmentInPartiallyOwnedConsolidatedSubsidiary
Namespace Prefix:	trn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Equity Method Investment, Aggregate Future Estimated Investment of Railcars

+ References

No definition available.

+ Details

Name:	trn_EquityMethodInvestmentAggregateFutureEstimatedInvestmentOfRailcars
Namespace Prefix:	trn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Equity Method Investment, Joint Venture Majority Ownership Percentage

+ References

No definition available.

+ Details

Name:	trn_EquityMethodInvestmentJVMajorityOwnershipPercentage
Namespace Prefix:	trn_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of subsidiaries.

+ References

No definition available.

+ Details

Name:	trn_NumberOfSubsidiaries
Namespace Prefix:	trn_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of Board Members

+ References

No definition available.

+ Details

Name:	trn_NumberofBoardMembers
Namespace Prefix:	trn_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of Board Members of Subsidiary, Designated by Parent

+ References

No definition available.

+ Details

Name:	trn_NumberofBoardMembersofSubsidiaryDesignatedbyParent
Namespace Prefix:	trn_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Parent Company Guarantees

+ References

No definition available.

+ Details

Name:	trn_ParentCompanyGuarantees
Namespace Prefix:	trn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(10))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 25
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8813-108599

+ Details

Name:	us-gaap_EquityMethodInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByParent
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Aggregate cash proceeds received from a combination of transactions in which noncurrent assets are sold, which may include the sale of a business, an investment in an affiliate (including an equity method investee), property, plant and equipment and intangible assets. Excludes sales of trading, available-for-sale, and held-to-maturity securities.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3179-108585

+ Details

Name:	us-gaap_ProceedsFromSalesOfBusinessAffiliateAndProductiveAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=trn_SignalRailHoldingsLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=trn_PartiallyOwnedSubsidiariesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=trn_RailcarLeasingAndManagementServicesGroupMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=trn_PartiallyOwnedSubsidiariesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: