v2.4.0.6
Document And Entity Information (USD $)
3 Months Ended
Mar. 31, 2013
May 06, 2013
Jun. 30, 2012
Entity information [Abstract]      
Entity Registrant Name Great Plains Energy Inc    
Entity Central Index Key 0001143068    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Filer Category Large Accelerated Filer    
Entity Public Float     $ 3,273,153,264
Entity Common Stock, Shares Outstanding   153,730,325  
Document Fiscal Year Focus 2013    
Document Fiscal Period Focus Q1    
Document Type 10-Q    
Amendment Flag false    
Document Period End Date Mar. 31, 2013