XML 101 R81.htm IDEA: XBRL DOCUMENT v3.22.0.1

Debt And Credit Agreements (Summary Of Total Debt Due And Outstanding) (Details)	12 Months Ended
	Dec. 31, 2021
Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, covenant terms, maximum debt to EBITDA ratio	4.00

X

- Definition

Line of credit facility, covenant terms, maximum debt to EBITDA ratio

+ References

No definition available.

+ Details

Name:	tg_LineOfCreditFacilityCovenantTermsMaximumDebtToEbitdaRatio
Namespace Prefix:	tg_
Data Type:	xbrli:pureItemType
Balance Type:	na
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_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=tg_SecuredRevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: