XML 173 R139.htm IDEA: XBRL DOCUMENT v3.3.1.900
Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated Other Comprehensive Income (Loss), Net of Tax (Changes in AOCI) (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning Balance $ (283) $ (95) $ (388)
Other Comprehensive Income before Reclassifications (30) (135) 299
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) 18 (53) (6)
Net Current Period Other Comprehensive Income (Loss) (12) (188) 293
Ending Balance (295) (283) (95)
Power [Member]      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning Balance (228) (63) (328)
Other Comprehensive Income before Reclassifications (27) (110) 276
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) 15 (55) (11)
Net Current Period Other Comprehensive Income (Loss) (12) (165) 265
Ending Balance (240) (228) (63)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning Balance 10 (2) 7
Other Comprehensive Income before Reclassifications 2 7 (2)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) (12) 5 (7)
Net Current Period Other Comprehensive Income (Loss) (10) 12 (9)
Ending Balance 0 10 (2)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Power [Member]      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning Balance 11 (1) 9
Other Comprehensive Income before Reclassifications 1 7 (2)
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) (12) 5 (8)
Net Current Period Other Comprehensive Income (Loss) (11) 12 (10)
Ending Balance 0 11 (1)
Accumulated Defined Benefit Plans Adjustment [Member]      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning Balance (411) (238) (485)
Other Comprehensive Income before Reclassifications (7) (184) 210
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) 32 11 37
Net Current Period Other Comprehensive Income (Loss) 25 (173) 247
Ending Balance (386) (411) (238)
Accumulated Defined Benefit Plans Adjustment [Member] | Power [Member]      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning Balance (351) (204) (422)
Other Comprehensive Income before Reclassifications (4) (156) 185
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) 28 9 33
Net Current Period Other Comprehensive Income (Loss) 24 (147) 218
Ending Balance (327) (351) (204)
Accumulated Net Unrealized Investment Gain (Loss) [Member]      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning Balance 118 145 90
Other Comprehensive Income before Reclassifications (25) 42 91
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) (2) (69) (36)
Net Current Period Other Comprehensive Income (Loss) (27) (27) 55
Ending Balance 91 118 145
Accumulated Net Unrealized Investment Gain (Loss) [Member] | Power [Member]      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Beginning Balance 112 142 85
Other Comprehensive Income before Reclassifications (24) 39 93
Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) (1) (69) (36)
Net Current Period Other Comprehensive Income (Loss) (25) (30) 57
Ending Balance $ 87 $ 112 $ 142