XML 24 R79.htm IDEA: XBRL DOCUMENT v3.2.0.727
Contingencies and Legal Proceedings Legal Proceedings (Details)
 1 Months Ended 9 Months Ended 12 Months Ended
Jul. 31, 2013
Legal_actions
May. 31, 2013
Jun. 30, 2012
Dec. 31, 2011
Legal_actions
Apr. 30, 2011
Groups
Agreements
Sep. 30, 2010
Mar. 31, 2010
People
Nov. 30, 2009
People
Legal_actions
Jun. 30, 2008
Legal_actions
Oct. 31, 2007
Legal_actions
Jun. 30, 2015
USD ($)
Legal_actions
Dec. 31, 2010
Years
Apr. 30, 2015
Legal_actions
Apr. 14, 2015
Megawatts
Jun. 30, 2011
USD ($)
Units
Megawatts
Jun. 30, 2010
USD ($)
Legal Proceedings                                
Possible additional future costs for compliance with Clean Air Act requirements | $                     $ 800,000,000          
Megawatts | Megawatts                           700    
Term of payments for civil penalty                     3 years          
TDEC civil penalties related to Gallatin | $                     $ 17,000          
Plaintiff civil penalties related to Gallatin | $                     $ 37,500          
Units Affected by Paradise Case                     2          
Number of claims dismissed related to NPDES permit                     7          
Number of claims filed on Gallatin NPDES permit                     8          
Number of reactors a CCOLA was submitted for                   2            
Number of units at John Sevier Fossil                     4          
General                                
Legal Proceedings                                
Legal loss contingency accrual | $                     $ 145,000,000          
Environmental Agreements                                
Legal Proceedings                                
Number of similar environmental agreements entered into | Agreements         2                      
Number of environmental agreements entered into with the EPA | Agreements         1                      
Number of environmental agreements entered into with Alabama, Kentucky, North Carolina, and Tennessee | Agreements         1                      
Number of environmental agreements entered into with environmental advocacy groups | Groups         3                      
Number of units to be idled | Units                             18  
Megawatts | Megawatts                             2,200  
Megawatts option 2 | Megawatts                             3,500  
Amount to be invested in certain TVA environmental projects | $                             $ 290,000,000  
Amount to be provided to fund environmental projects | $                             60,000,000  
Amount to pay civil penalties | $                             $ 10,000,000  
Kingston Ash Spill                                
Legal Proceedings                                
Number of lawsuits filed                     78          
Number of lawsuits dismissed                     15   2      
Loss Contingency, Claims Dismissed, Number                     63          
Number of active lawsuits                     9          
Payments for Legal Settlements | $                     $ 28,000,000          
Loss Contingency, Claims Settled, Number                     7          
Civil penalty order issued June 1, 2010 | $                               $ 12,000,000
Amount of civil penalty order satisfied | $                     $ 10,000,000          
Credit against civil penalty order | $                     2,000,000          
Down payment on natural resource damages | $                     750,000          
Case Involving Tennessee Valley Authority Retirement System                                
Legal Proceedings                                
Number of participants that filed suit | People             8                  
Number of TVARS Board members | People             6                  
Retirement age of eligibility for cost of living adjustment before January 1, 2010 | Years                       55        
Retirement age of eligibility for cost of living adjustment after January 1, 2010 | Years                       60        
Number of days to file an ammended complaint           14 days                    
Case Involving the NRC Waste Confidence Decision on Spent Nuclear Fuel Storage                                
Legal Proceedings                                
Number of years that spent fuel can be stored after a plant's license is terminated     60 years                          
Administrative Proceedings Regarding Sequoyah U1 and U2 [Member]                                
Legal Proceedings                                
Number of contentions submitted by BREDL BEST and MATRR   8                            
Opposed contentions   8                            
Number of petitioners with standing 1                              
Number of petitioners 3                              
Number of contentions dismissed 7                              
Number of contentions left 1                              
Administrative Proceedings Regarding Bellefonte Units 3 and 4                                
Legal Proceedings                                
Number of contentions left                 2              
Number of admitted contentions submitted by BREDL and SACE                 4              
Number of contentions submitted by BREDL and SACE                 20              
Number of contentions no longer admitted                 2              
Administrative Proceedings Regarding Watts Bar Nuclear Plant Unit 2                                
Legal Proceedings                                
Number of contentions dismissed               1                
Number of contentions admitted for hearing               2                
Number of SACE contentions               7                
Number of other petitioners | People               4                
Number of contentions remaining               1                
Petitions Resulting from Japanese Nuclear Events                                
Legal Proceedings                                
Number of requests accepted by the NRC       5                        
Other Noncurrent Liabilities [Member] | General                                
Legal Proceedings                                
Legal loss contingency accrual | $                     63,000,000          
Accounts payable and accrued liabilities | General                                
Legal Proceedings                                
Legal loss contingency accrual | $                     $ 82,000,000