Amount of shares earned as a % of target award.

No definition available.

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

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award percentage attained

+ References

No definition available.

+ Details

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

- Definition

Award percentage earned based on metric over the performance period.

+ References

No definition available.

+ Details

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

- Definition

Percentage of the value of the incentive plan in earned cash.

+ References

No definition available.

+ Details

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

- Definition

Incentive Compensation Plan, Threshold Target Award for Granting Stock Award.

+ References

No definition available.

+ Details

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

- Definition

Number of performance metrics in restricted shares award type plan.

+ References

No definition available.

+ Details

Name:	trs_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfPerformanceMetricsInRestrictedSharesAwardTypePlan
Namespace Prefix:	trs_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of the value of the incentive plan in restriced shares.

+ References

No definition available.

+ Details

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

- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph g(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

-URI http://asc.fasb.org/extlink&oid=6793087&loc=d3e301413-122809

+ Details

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

- Definition

The number of shares issued pursuant to the terms of the deferred compensation plan as of the balance sheet date.

+ References

+ Details

Name:	us-gaap_DeferredCompensationArrangementWithIndividualSharesIssued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Aggregate unrecognized cost of share-based awards, other than options, made to employees under an equity-based compensation plan, that have yet to vest.

+ References

No definition available.

+ Details

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

- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

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

Equity Awards - Restricted Shares Narrative (Details) (USD $)	3 Months Ended						3 Months Ended													12 Months Ended
	Mar. 31, 2013 Restricted Shares [Member]	Mar. 31, 2012 Restricted Shares [Member]	Mar. 31, 2013 Restricted Shares [Member] Non-employee independent director [Member] Deferred Compensation, Share-based Payments [Member]	Mar. 31, 2013 Plan 1 [Member] Service-based restriced shares [Member]	Mar. 31, 2013 Plan 2 [Member] Service-based restriced shares [Member]	Mar. 31, 2013 Plan 3 [Member] number	Mar. 31, 2013 Plan 3 [Member] Restricted Shares [Member]	Mar. 31, 2013 Plan 3 [Member] Service-based restriced shares [Member]	Mar. 31, 2013 Plan 3 [Member] Performance-based restriced shares [Member]	Mar. 31, 2013 Plan 5 [Member] Service-based restriced shares [Member]	Mar. 31, 2013 Plan 5 [Member] Service-based restriced shares [Member] Non-employee independent director [Member]	Mar. 31, 2013 Minimum [Member] Plan 2 [Member] Service-based restriced shares [Member]	Mar. 31, 2013 3 year cash flow metric [Member] Plan 3 [Member] Performance-based restriced shares [Member]	Mar. 31, 2013 3 year cash flow metric [Member] Minimum [Member] Plan 3 [Member] Performance-based restriced shares [Member]	Mar. 31, 2013 3 year cash flow metric [Member] Maximum [Member] Plan 3 [Member] Performance-based restriced shares [Member]	Mar. 31, 2013 3 year EPS CAGR metric [Member] Plan 3 [Member] Performance-based restriced shares [Member]	Mar. 31, 2013 3 year EPS CAGR metric [Member] Minimum [Member] Plan 3 [Member] Performance-based restriced shares [Member]	Mar. 31, 2013 3 year EPS CAGR metric [Member] Maximum [Member] Plan 3 [Member] Performance-based restriced shares [Member]	Mar. 31, 2013 2012 EPS growth metric [Member] Plan 4 [Member] Performance-based restriced shares [Member]	Dec. 31, 2012 2012 EPS growth metric [Member] Plan 4 [Member] Performance-based restriced shares [Member]	Dec. 31, 2012 2012 & 2013 EPS CAGR metric [Member] Plan 4 [Member] Performance-based restriced shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares issued related to director fee deferrals			1,508
Number of Unvested Restricted Shares Granted	401,110			29,498	41,480		238,808	119,404,000	119,404,000		17,240								72,576
Award requisite service period				3 years	1 year			3 years		1 year
ICP, Threshold target for granting stock awards												$ 20,000
Cash value of incentive plan					80.00%
Restriced shares value of incentive plan					20.00%
Award vesting period									3 years
Award percentage earned based on metric over the performance period													25.00%			75.00%				60.00%	40.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award percentage attained																				175.00%
Number of performance metrics in restricted shares award type plan						2
Amount of shares earned % of target award														30.00%	200.00%		30.00%	250.00%
Unrecognized unvested restricted shares-based compensation expense	11,800,000
Weighted-average period for recognition of the unrecognized unvested restricted shares-based compensation expense	1 year 11 months
Restricted shares-based compensation expense	$ 2,700,000	$ 1,400,000