Loss Contingency, Number of Plaintiffs Specifying Damages Sought

No definition available.

Name:	trs_LossContingencyNumberofPlaintiffsSpecifyingDamagesSought
Namespace Prefix:	trs_
Data Type:	xbrli:integerItemType
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- Definition

Number of pending cases related to a loss contingency

+ References

No definition available.

+ Details

Name:	trs_LossContingencyPendingCasesNumber
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Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

Percentage of Settlement and Defense Costs Covered by Insurance

+ References

No definition available.

+ Details

Name:	trs_PercentageOfSettlementAndDefenseCostsCoveredByInsurance
Namespace Prefix:	trs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

+ References

No definition available.

+ Details

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

- 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_LossContingenciesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
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- Definition

Number of pending claims pertaining to a loss contingency.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

+ Details

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Balance Type:	na
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- Details

Name:	us-gaap_LossContingenciesByNatureOfContingencyAxis=us-gaap_AsbestosIssueMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	trs_DamagesSoughtTypeAxis=trs_PunitiveOnlyDamagesMember
Namespace Prefix:
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Period Type:

- Details

Name:	us-gaap_LitigationStatusAxis=us-gaap_PendingLitigationMember
Namespace Prefix:
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- Details

Name:	trs_DamagesSoughtTypeAxis=trs_CompensatoryOnlyDamagesMember
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Commitments and Contingencies Asbestos Narrative (Details) - Asbestos [Member] $ in Millions	339 Months Ended
	Mar. 31, 2019 USD ($) claimants cases	Dec. 31, 2018 claimants	Dec. 31, 2017 claimants
Loss Contingencies [Line Items]
Loss Contingency, Pending Cases, Number \| cases	370
Loss Contingency, Pending Claims, Number	4,811	4,820	5,256
Total settlement costs \| $	$ 9.0
Percentage of settlement and defense costs covered by insurance	40.00%
Punitive Only Damages [Member] \| Pending Litigation [Member]
Loss Contingencies [Line Items]
Number of pending claims seeking specific amounts of damages	0
Compensatory Only Damages [Member] \| Pending Litigation [Member]
Loss Contingencies [Line Items]
Number of pending claims seeking specific amounts of damages	54