XML 27 R42.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Derivative Financial Instruments (Narrative) (Details) (USD $) | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2015 lb | Dec. 31, 2013 lb | Dec. 31, 2014
Derivative [Line Items] |  |  |
Amounts of unrealized after tax gains (losses) to be Reclassified within Twelve Months | $ 800,000 us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths |  |
Aluminum Futures Contracts |  |  |
Derivative [Line Items] |  |  |
Notional Amount | 14,000,000 invest_DerivativeNotionalAmount / us-gaap_DerivativeInstrumentRiskAxis = tg_AluminumFuturesContractsMember |  | 8,600,000 invest_DerivativeNotionalAmount / us-gaap_DerivativeInstrumentRiskAxis = tg_AluminumFuturesContractsMember
Weight of aluminum that hedged future purchase of aluminum to meet fixed - price forward sales contract obligations, lbs | 13,000,000 us-gaap_DerivativeNonmonetaryNotionalAmountMass / us-gaap_DerivativeInstrumentRiskAxis = tg_AluminumFuturesContractsMember | 7,800,000 us-gaap_DerivativeNonmonetaryNotionalAmountMass / us-gaap_DerivativeInstrumentRiskAxis = tg_AluminumFuturesContractsMember |
Net asset (liability), Fair Value | (1,282,000)us-gaap_DerivativeFairValueOfDerivativeNet / us-gaap_DerivativeInstrumentRiskAxis = tg_AluminumFuturesContractsMember |  | (236,000)us-gaap_DerivativeFairValueOfDerivativeNet / us-gaap_DerivativeInstrumentRiskAxis = tg_AluminumFuturesContractsMember
Derivatives Not Designated As Hedging Instruments | Aluminum Futures Contracts |  |  |
Derivative [Line Items] |  |  |
Net asset (liability), Fair Value | 0 us-gaap_DerivativeFairValueOfDerivativeNet / us-gaap_DerivativeInstrumentRiskAxis = tg_AluminumFuturesContractsMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember |  |
Accrued Expenses [Member] | Derivatives Not Designated As Hedging Instruments | Aluminum Futures Contracts |  |  |
Derivative [Line Items] |  |  |
Derivative Asset, Fair Value, Gross Asset | 28,000 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_BalanceSheetLocationAxis = tg_AccruedExpensesMember / us-gaap_DerivativeInstrumentRiskAxis = tg_AluminumFuturesContractsMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember |  | 7,000 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_BalanceSheetLocationAxis = tg_AccruedExpensesMember / us-gaap_DerivativeInstrumentRiskAxis = tg_AluminumFuturesContractsMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember
Derivative Liability, Fair Value, Gross Liability | 28,000 us-gaap_DerivativeFairValueOfDerivativeLiability / us-gaap_BalanceSheetLocationAxis = tg_AccruedExpensesMember / us-gaap_DerivativeInstrumentRiskAxis = tg_AluminumFuturesContractsMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember |  | 7,000 us-gaap_DerivativeFairValueOfDerivativeLiability / us-gaap_BalanceSheetLocationAxis = tg_AccruedExpensesMember / us-gaap_DerivativeInstrumentRiskAxis = tg_AluminumFuturesContractsMember / us-gaap_HedgingDesignationAxis = us-gaap_NondesignatedMember
Accrued Expenses [Member] | Derivatives Designated As Hedging Instruments [Member] | Aluminum Futures Contracts |  |  |
Derivative [Line Items] |  |  |
Derivative Asset, Fair Value, Gross Asset | 2,000 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_BalanceSheetLocationAxis = tg_AccruedExpensesMember / us-gaap_DerivativeInstrumentRiskAxis = tg_AluminumFuturesContractsMember / us-gaap_HedgingDesignationAxis = us-gaap_DesignatedAsHedgingInstrumentMember |  | 82,000 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_BalanceSheetLocationAxis = tg_AccruedExpensesMember / us-gaap_DerivativeInstrumentRiskAxis = tg_AluminumFuturesContractsMember / us-gaap_HedgingDesignationAxis = us-gaap_DesignatedAsHedgingInstrumentMember
Derivative Liability, Fair Value, Gross Liability | $ 1,284,000 us-gaap_DerivativeFairValueOfDerivativeLiability / us-gaap_BalanceSheetLocationAxis = tg_AccruedExpensesMember / us-gaap_DerivativeInstrumentRiskAxis = tg_AluminumFuturesContractsMember / us-gaap_HedgingDesignationAxis = us-gaap_DesignatedAsHedgingInstrumentMember |  | $ 318,000 us-gaap_DerivativeFairValueOfDerivativeLiability / us-gaap_BalanceSheetLocationAxis = tg_AccruedExpensesMember / us-gaap_DerivativeInstrumentRiskAxis = tg_AluminumFuturesContractsMember / us-gaap_HedgingDesignationAxis = us-gaap_DesignatedAsHedgingInstrumentMember

X
- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
Name: | invest_DerivativeNotionalAmount
Namespace Prefix: | invest_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Definition The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994 + Details
Name: | us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (a),(c) -URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226000-175313 + Details
Name: | us-gaap_DerivativeFairValueOfDerivativeAsset
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (a),(c) -URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226000-175313 + Details
Name: | us-gaap_DerivativeFairValueOfDerivativeLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13433-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13495-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 + Details
Name: | us-gaap_DerivativeFairValueOfDerivativeNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_DerivativeLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Nominal mass used to calculate payments on a derivative instrument. + References No definition available. + Details
Name: | us-gaap_DerivativeNonmonetaryNotionalAmountMass
Namespace Prefix: | us-gaap_
Data Type: | num:massItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=tg_AccruedExpensesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=tg_AluminumFuturesContractsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_HedgingDesignationAxis=us-gaap_NondesignatedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |