XML 144 R100.htm IDEA: XBRL DOCUMENT v3.8.0.1
Asset Retirement Obligations (Rollforward)(Details) - USD ($)
$ in Millions
2 Months Ended 12 Months Ended
Dec. 31, 2016
Dec. 31, 2017
Dec. 31, 2016
Oct. 31, 2016
Asset Retirement Obligation [Line Items]        
Beginning Balance   $ 10,611 $ 10,249  
Acquisitions     22  
Accretion expense   435 400  
Liabilities settled   (619) (613)  
Liabilities incurred in the current year   51 51  
Revisions in estimates of cash flows   (303) 502  
Ending Balance $ 10,611 10,175 10,611  
Duke Energy Carolinas [Member]        
Asset Retirement Obligation [Line Items]        
Beginning Balance   3,895 3,918  
Accretion expense   184 187  
Liabilities settled   (282) (287)  
Liabilities incurred in the current year   5    
Revisions in estimates of cash flows   (192) 77  
Ending Balance 3,895 3,610 3,895  
Progress Energy [Member]        
Asset Retirement Obligation [Line Items]        
Beginning Balance   5,475 5,369  
Acquisitions     2  
Accretion expense   228 230  
Liabilities settled   (270) (272)  
Liabilities incurred in the current year     3  
Revisions in estimates of cash flows   (19) 143  
Ending Balance 5,475 5,414 5,475  
Duke Energy Progress [Member]        
Asset Retirement Obligation [Line Items]        
Beginning Balance   4,697 4,567  
Accretion expense   195 194  
Liabilities settled   (204) (212)  
Liabilities incurred in the current year     3  
Revisions in estimates of cash flows   (15) 145  
Ending Balance 4,697 4,673 4,697  
Duke Energy Florida [Member]        
Asset Retirement Obligation [Line Items]        
Beginning Balance   778 802  
Acquisitions     2  
Accretion expense   33 35  
Liabilities settled   (65) (60)  
Revisions in estimates of cash flows   (4) (1)  
Ending Balance 778 742 778  
Duke Energy Ohio [Member]        
Asset Retirement Obligation [Line Items]        
Beginning Balance   77 125  
Accretion expense   3 5  
Liabilities settled   (7) (5)  
Liabilities incurred in the current year   7    
Revisions in estimates of cash flows   4 (48)  
Ending Balance 77 84 77  
Duke Energy Indiana [Member]        
Asset Retirement Obligation [Line Items]        
Beginning Balance   866 525  
Accretion expense   32 24  
Liabilities settled   (49) (49)  
Liabilities incurred in the current year   29 29  
Revisions in estimates of cash flows   (97) 337  
Ending Balance 866 781 866  
Piedmont Natural Gas [Member]        
Asset Retirement Obligation [Line Items]        
Beginning Balance 14 14   $ 20
Accretion expense   1   1
Liabilities settled (1) (8)   (7)
Liabilities incurred in the current year 1 8   6
Revisions in estimates of cash flows       (6)
Ending Balance $ 14 $ 15 $ 14 $ 14