Defined Benefit Plan Future Amortization of Gain (Loss), Net of Tax

No definition available.

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

- Definition

Defined Contribution and Other Retirement Plans, Estimated Future Employer Contributions in Current Fiscal Year

+ References

No definition available.

+ Details

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

- Definition

Defined Contribution Plan, Employer Contribution Based on Service

+ References

No definition available.

+ Details

Name:	trn_DefinedContributionPlanEmployerContributionBasedOnService
Namespace Prefix:	trn_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Multiemployer Plan, Expected Contributions in Next Fiscal Year

+ References

No definition available.

+ Details

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

- Definition

Plan assets expected to be returned.

+ References

No definition available.

+ Details

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

- Details

Name:	trn_ScheduleOfBenefitPlansDisclosuresLineItems
Namespace Prefix:	trn_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

After tax net amount of gain (loss) that are not yet recognized as a component of net periodic benefit cost, and that are recognized as increases (decreases) in other comprehensive income as they arise.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesAfterTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The pretax net amount of gains and losses that are not yet recognized as a component of net periodic benefit cost, and that are recognized as increases or decreases in other comprehensive income as they arise. Gains and losses are due to changes in the value of either the benefit obligation or the plan assets resulting from experience different from that assumed or from a change in an actuarial assumption, or the consequence of a decision to temporarily deviate from the substantive plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (j)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

+ Details

Name:	us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount after tax of cost (credit) due to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation, which has not yet been recognized as a component of net periodic benefit cost.

+ References

No definition available.

+ Details

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

- Definition

Amount related to the pretax cost of benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation, which has not yet been recognized as components of net periodic benefit cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (j)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (j)

-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Prior Service Cost

-URI http://asc.fasb.org/extlink&oid=6521920

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Prior Service Cost

-URI http://asc.fasb.org/extlink&oid=6521884

+ Details

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

- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ References

+ Details

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

- Definition

Amount included in accumulated other comprehensive income (AOCI) related to gain (loss) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedBenefitPlanFutureAmortizationOfGainLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan in the current remaining fiscal period.

+ References

No definition available.

+ Details

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

- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

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

- Definition

Amount of contributions made to multiemployer plans by the employer. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=35742057&loc=SL14450702-114947

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 9

-URI http://asc.fasb.org/extlink&oid=35742057&loc=SL14450691-114947

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 5

-Subparagraph (e)(1)

-URI http://asc.fasb.org/extlink&oid=35742057&loc=SL14450657-114947

+ Details

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

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Employee Retirement Plans (Details Textual) (USD $)	12 Months Ended
Employee Retirement Plans (Details Textual) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of Benefit Plans Disclosures [Line Items]
Plan assets expected to be returned	$ 0trn_PlanAssetsExpectedToBeReturned
Prior service cost included in AOCL	100,000
Prior service cost included in AOCL, net of tax	100,000
Unrecognized actuarial losses included in AOCL	138,100,000
Unrecognized actuarial losses included in AOCL, net of tax	86,900,000
Actuarial loss expected to be recognized in net periodic pension cost within twelve months	5,200,000
Actuarial loss expected to be recognized in net periodic pension cost within twelve months, net of tax	3,300,000
Expected employer contributions to defined benefit plans next year	19,700,000
Actual employer contributions to defined benefit plans	15,000,000	18,900,000
Expected employer contributions to 401(k) plans and Supplemental Profit Sharing Plan next year	16,100,000
Actual employer contributions to 401(k) plans and Supplemental Profit Sharing Plan	14,000,000
Multiemployer plan, expected contributions in following year	2,700,000
Multiemployer plan contributions	$ 600,000	$ 0	$ 0
Minimum
Schedule of Benefit Plans Disclosures [Line Items]
Company contributions to the Profit Sharing Plan as a percentage of eligible compensation based on service	1.00%
Maximum
Schedule of Benefit Plans Disclosures [Line Items]
Company contributions to the Profit Sharing Plan as a percentage of eligible compensation based on service	3.00%