v3.3.1.900
Document And Entity Information - USD ($)
12 Months Ended
Dec. 31, 2015
Jan. 29, 2016
Jun. 30, 2015
Document And Entity Information [Abstract]      
Entity Registrant Name TREDEGAR CORP    
Entity Central Index Key 0000850429    
Current Fiscal Year End Date --12-31    
Entity Filer Category Large Accelerated Filer    
Document Type 10-K    
Document Period End Date Dec. 31, 2015    
Document Fiscal Year Focus 2015    
Document Fiscal Period Focus (Q1,Q2,Q3,FY) FY    
Amendment Flag false    
Entity Common Stock, Shares Outstanding   32,682,162  
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Public Float     $ 560,178,695