XML 1118 R1.htm IDEA: XBRL DOCUMENT v2.4.1.9
Document and Entity Information (USD $)
In Billions, except Share data, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Jan. 31, 2015
Jun. 30, 2014
Document Information [Line Items]      
Entity Registrant Name SOUTHERN CO    
Entity Central Index Key 0000092122    
Document Type 10-K    
Document Period End Date Dec. 31, 2014    
Amendment Flag false    
Document Fiscal Year Focus 2014    
Document Fiscal Period Focus FY    
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     $ 40.7dei_EntityPublicFloat
Entity Common Stock, Shares Outstanding   909,877,898dei_EntityCommonStockSharesOutstanding  
Alabama Power [Member]      
Document Information [Line Items]      
Entity Registrant Name ALABAMA POWER CO    
Entity Central Index Key 0000003153    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer Yes    
Entity Filer Category Non-accelerated Filer    
Entity Common Stock, Shares Outstanding   30,537,500dei_EntityCommonStockSharesOutstanding
/ dei_LegalEntityAxis
= so_AlabamaPowerMember
 
Georgia Power [Member]      
Document Information [Line Items]      
Entity Registrant Name GEORGIA POWER CO    
Entity Central Index Key 0000041091    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer Yes    
Entity Filer Category Non-accelerated Filer    
Entity Common Stock, Shares Outstanding   9,261,500dei_EntityCommonStockSharesOutstanding
/ dei_LegalEntityAxis
= so_GeorgiaPowerMember
 
Gulf Power [Member]      
Document Information [Line Items]      
Entity Registrant Name GULF POWER CO    
Entity Central Index Key 0000044545    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer No    
Entity Filer Category Non-accelerated Filer    
Entity Common Stock, Shares Outstanding   5,642,717dei_EntityCommonStockSharesOutstanding
/ dei_LegalEntityAxis
= so_GulfPowerMember
 
Mississippi Power [Member]      
Document Information [Line Items]      
Entity Registrant Name MISSISSIPPI POWER CO    
Entity Central Index Key 0000066904    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer No    
Entity Filer Category Non-accelerated Filer    
Entity Common Stock, Shares Outstanding   1,121,000dei_EntityCommonStockSharesOutstanding
/ dei_LegalEntityAxis
= so_MississippiPowerMember
 
Southern Power [Member]      
Document Information [Line Items]      
Entity Registrant Name SOUTHERN POWER CO    
Entity Central Index Key 0001160661    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer No    
Entity Filer Category Non-accelerated Filer    
Entity Common Stock, Shares Outstanding   1,000dei_EntityCommonStockSharesOutstanding
/ dei_LegalEntityAxis
= so_SouthernPowerMember