Long-term Debt - Credit Agreement (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Net leverage ratio	2.50
U.S. bank debt and receivables facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Unused Borrowing Capacity, Amount	$ 176.7	$ 126.5
Revolving credit and term loan facilities [Member]
Debt Instrument [Line Items]
Incremental debt commitments capacity	$ 300.0
term loan A facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Jun. 30, 2020
Required prepayments under term loan A facility	$ 0.0
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Jun. 30, 2020
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.625%
Senior Secured Term Loan A [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.625%
Debt Instrument, Face Amount	$ 275.0
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	500.0
Revolving Credit Facility, Capacity Available for Foreign Revolver Loans	75.0
Revolving Credit Facility, Amount Outstanding	47.7	75.9
Revolving Credit Facility, Remaining Borrowing Capacity	436.0	408.2
Letters of credit [Member]
Debt Instrument [Line Items]
Letters of Credit, Maximum Borrowing Capacity	40.0
Letters of Credit Outstanding, Amount	$ 16.3	$ 15.9
Fair Value, Inputs, Level 2 [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Debt, Fair Value, % of par value	99.30%	99.30%
Fair Value, Inputs, Level 2 [Member] \| term loan A facility [Member]
Debt Instrument [Line Items]
Long-term Debt, Fair Value, % of par value	99.60%	99.60%
Principal payment, quarterly December 2015 through September 2018 [Member] \| term loan A facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Periodic Payment, Principal	$ 3.4
Principal payment, quarterly December 2018 through March 2020 [Member] \| term loan A facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Periodic Payment, Principal	5.2
Final principal payment, June 30, 2020 [Member] \| term loan A facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Periodic Payment, Principal	$ 202.8

Incremental debt commitments capacity.

No definition available.

Name:	trs_IncrementalDebtCommitmentsCapacity
Namespace Prefix:	trs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the letters of credit.

+ References

No definition available.

+ Details

Name:	trs_LetterOfCreditMaximumBorrowingCapacity
Namespace Prefix:	trs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fair value of long-term debt presented as a % of par value.

+ References

No definition available.

+ Details

Name:	trs_LongTermDebtFairValueOfParValue
Namespace Prefix:	trs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Net leverage ratio, as defined

+ References

No definition available.

+ Details

Name:	trs_NetLeverageRatio
Namespace Prefix:	trs_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Required prepayments under term loan A facility

+ References

No definition available.

+ Details

Name:	trs_RequiredprepaymentsundertermloanAfacility
Namespace Prefix:	trs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

Name:	us-gaap_DebtInstrumentMaturityDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the required periodic payments applied to principal.

+ References

+ Details

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

- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ References

+ Details

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

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Definition

The maximum amount of borrowing capacity under a line of credit that is available as of the balance sheet date for a specific purpose other than for financing goods acquired for inventory or imminent delivery to a customer.

+ References

No definition available.

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=trs_TermloanAfacilityMember
Namespace Prefix:
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- Details

Name:	us-gaap_DebtInstrumentAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=trs_SeniorSecuredTermLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LetterOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_LongtermDebtTypeAxis=trs_TermloanAfacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	trs_PrincipalPaymentScheduleAxis=trs_PrincipalpaymentquarterlyDecember2015throughSeptember2018Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	trs_PrincipalPaymentScheduleAxis=trs_PrincipalpaymentquarterlyDecember2018throughMarch2020Member
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	trs_PrincipalPaymentScheduleAxis=trs_FinalprincipalpaymentJune302020Member
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