XML 69 R51.htm IDEA: XBRL DOCUMENT
v3.19.2

Accumulated Other Comprehensive Income (Loss) (Schedule Of After-Tax Changes In Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Selling, general and administrative | $ 23,864 | $ 20,946 | $ 45,875 | $ 42,775
Beginning of Period |  |  | (179,987) | (176,669)
Other comprehensive income (loss) before reclassifications |  |  | (1,501) | (9,734)
Amounts reclassified from accumulated other comprehensive income (loss) |  |  | 5,644 | 4,862
Net other comprehensive income (loss) - current period | 3,207 | (9,105) | 4,143 | (4,872)
End of Period | (175,844) | (181,541) | (175,844) | (181,541)
Income before income taxes | 18,917 | 19,269 | 42,728 | 42,721
Income Tax Expense (Benefit) | 4,440 | 4,547 | 8,467 | 9,834
Net income | 14,477 | 14,722 | 34,261 | 32,887
Foreign Currency Translation |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Beginning of Period |  |  | (96,940) | (86,178)
Other comprehensive income (loss) before reclassifications |  |  | (283) | (8,905)
Amounts reclassified from accumulated other comprehensive income (loss) |  |  | 0 | 0
Net other comprehensive income (loss) - current period |  |  | (283) | (8,905)
End of Period | (97,223) | (95,083) | (97,223) | (95,083)
Gain (Loss) on Derivative Financial Instruments |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Beginning of Period |  |  | (1,601) | 459
Other comprehensive income (loss) before reclassifications |  |  | (1,218) | (829)
Amounts reclassified from accumulated other comprehensive income (loss) |  |  | 1,486 | (361)
Net other comprehensive income (loss) - current period |  |  | 268 | (1,190)
End of Period | (1,333) | (731) | (1,333) | (731)
Pension & Other Post-retirement Benefit Adjustment |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Beginning of Period |  |  | (81,446) | (90,950)
Other comprehensive income (loss) before reclassifications |  |  | 0 | 0
Amounts reclassified from accumulated other comprehensive income (loss) |  |  | 4,158 | 5,223
Net other comprehensive income (loss) - current period |  |  | 4,158 | 5,223
End of Period | (77,288) | (85,727) | (77,288) | (85,727)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Gain (Loss) on Derivative Financial Instruments |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Income before income taxes | (959) | 350 | (1,752) | 556
Income Tax Expense (Benefit) | (131) | 142 | (266) | 195
Net income | (828) | 208 | (1,486) | 361
Reclassification out of Accumulated Other Comprehensive Income [Member] | Pension & Other Post-retirement Benefit Adjustment |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Income Tax Expense (Benefit) | (593) | (761) | (1,185) | (1,523)
Net income | (2,079) | (2,611) | (4,158) | (5,223)
Amortization Of Prior Service Costs And Net Gains Loss | (2,672) | (3,372) | (5,343) | (6,746)
Aluminum Futures Contracts [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Gain (Loss) on Derivative Financial Instruments |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Cost of goods sold | (606) | 712 | 1,223 | (944)
Cost of Sales [Member] | Foreign Currency Forward Contracts [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member] | Gain (Loss) on Derivative Financial Instruments |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Cost of goods sold | $ 16 | $ 16 | $ 31 | $ 31

X
- Definition Amortization Of Prior Service Costs And Net Gains Loss + References No definition available. + Details
Name: | tg_AmortizationOfPriorServiceCostsAndNetGainsLoss
Namespace Prefix: | tg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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

X
- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e637-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669686-108580 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e681-108580 + Details
Name: | us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.2(a),(d)) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 + Details
Name: | us-gaap_CostOfGoodsAndServicesSold
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 20 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=68072869&loc=d3e41242-110953 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(10)) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(8)) -URI http://asc.fasb.org/extlink&oid=114873790&loc=SL114874131-224263 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(15)) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 + Details
Name: | us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 20 -Section 45 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109238882&loc=d3e38679-109324 + Details
Name: | us-gaap_IncomeTaxExpenseBenefit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669619-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(22)) -URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669625-108580 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(18)) -URI http://asc.fasb.org/extlink&oid=114873790&loc=SL114874131-224263 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(20)) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
Name: | us-gaap_NetIncomeLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount after tax, before reclassification adjustments of other comprehensive income (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669686-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 55 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=109228884&loc=d3e1436-108581 + Details
Name: | us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount after tax and reclassification adjustments of other comprehensive income (loss). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669619-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 55 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=109228884&loc=d3e1436-108581 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1B -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669625-108580 + Details
Name: | us-gaap_OtherComprehensiveIncomeLossNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount after tax of reclassification adjustments of other comprehensive income (loss). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 17B -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL34724394-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669686-108580 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 55 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=109228884&loc=d3e1436-108581 + Details
Name: | us-gaap_ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=68048583&loc=d3e3636-108311 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.4) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 + Details
Name: | us-gaap_SellingGeneralAndAdministrativeExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedTranslationAdjustmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeAxis=us-gaap_ReclassificationOutOfAccumulatedOtherComprehensiveIncomeMember
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_IncomeStatementLocationAxis=us-gaap_CostOfSalesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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