XML 14 R1.htm IDEA: XBRL DOCUMENT v3.10.0.1
DEI Document - USD ($)
 12 Months Ended
Dec. 31, 2018
Feb. 04, 2019
Jun. 30, 2018
Entity Information [Line Items]      
Entity Registrant Name PORTLAND GENERAL ELECTRIC CO /OR/    
Entity Central Index Key 0000784977    
Document Type 10-K    
Document Period End Date Dec. 31, 2018    
Amendment Flag false    
Document Fiscal Year Focus 2018    
Document Fiscal Period Focus FY    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer Yes    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Filer Category Large Accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
Entity Shell Company false    
Entity Common Stock, Shares Outstanding   89,269,775  
Entity Public Float     $ 3,802,406,147
Trading Symbol POR