Cover - shares	9 Months Ended
	Sep. 30, 2022	Nov. 04, 2022
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	1-10258
Entity Registrant Name	Tredegar Corporation
Entity Incorporation, State or Country Code	VA
Entity Tax Identification Number	54-1497771
Entity Address, Address Line One	1100 Boulders Parkway
Entity Address, City or Town	Richmond,
Entity Address, State or Province	VA
Entity Address, Postal Zip Code	23225
City Area Code	(804)
Local Phone Number	330-1000
Title of 12(b) Security	Common stock, no par value
Trading Symbol	TG
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0000850429
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q3
Document Period End Date	Sep. 30, 2022
Amendment Flag	false
Entity Common Stock, Shares Outstanding		34,000,642