XML 110 R86.htm IDEA: XBRL DOCUMENT v3.7.0.1
Accumulated Other Comprehensive Income (Loss), Net of Tax (Reclassifications of AOCI) (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Dec. 31, 2016
Reclassification out of Accumulated Other Comprehensive Income [Line Items]          
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax $ 15 $ (19) $ 33 $ (44)  
Reclassification from Accumulated Other Comprehensive Income, Current Period, Tax (8) 9 (17) 20  
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax 7 (10) 16 (24)  
Cash Flow Hedges [Member]          
Reclassification out of Accumulated Other Comprehensive Income [Line Items]          
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax 0 0 0 0 $ 0
Pension and OPEB Plans [Member]          
Reclassification out of Accumulated Other Comprehensive Income [Line Items]          
Reclassification Adjustment from AOCI, Pension and OPEB, Pre-Tax (10) (14) (20) (28)  
Reclassification Adjustment from AOCI, Pension and OPEB, Tax 4 6 8 12  
Reclassification Adjustment from AOCI, Pension and OPEB, After-Tax (6) (8) (12) (16)  
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax (6) (8) (12) (16)  
Available-for-Sale Securities [Member]          
Reclassification out of Accumulated Other Comprehensive Income [Line Items]          
Reclassification for Available for Sale Securities, Pre-Tax 25 (5) 53 (16)  
Reclassification for Available for Sale Securities, Tax (12) 3 (25) 8  
Reclassification for Available for Sale Securities, After-Tax 13 (2) 28 (8)  
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax 13 (2) 28 (8)  
Power [Member]          
Reclassification out of Accumulated Other Comprehensive Income [Line Items]          
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax 16 (18) 26 (41)  
Reclassification from Accumulated Other Comprehensive Income, Current Period, Tax (9) 8 (15) 18  
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax 7 (10) 11 (23)  
Power [Member] | Cash Flow Hedges [Member]          
Reclassification out of Accumulated Other Comprehensive Income [Line Items]          
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax 0 0 0 0  
Power [Member] | Pension and OPEB Plans [Member]          
Reclassification out of Accumulated Other Comprehensive Income [Line Items]          
Reclassification Adjustment from AOCI, Pension and OPEB, Pre-Tax (8) (12) (17) (24)  
Reclassification Adjustment from AOCI, Pension and OPEB, Tax 3 5 7 10  
Reclassification Adjustment from AOCI, Pension and OPEB, After-Tax (5) (7) (10) (14)  
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax (5) (7) (10) (14)  
Power [Member] | Available-for-Sale Securities [Member]          
Reclassification out of Accumulated Other Comprehensive Income [Line Items]          
Reclassification for Available for Sale Securities, Pre-Tax 24 (6) 43 (17)  
Reclassification for Available for Sale Securities, Tax (12) 3 (22) 8  
Reclassification for Available for Sale Securities, After-Tax 12 (3) 21 (9)  
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax 12 (3) 21 (9)  
Operating Expense [Member] | Pension and OPEB Plans [Member]          
Reclassification out of Accumulated Other Comprehensive Income [Line Items]          
Amortization of Prior Service (Cost) Credit, Pre-Tax 2 3 4 6  
Amortization of Prior Service (Cost) Credit, Tax (1) (1) (2) (2)  
Amortization of Prior Service (Cost) Credit, After-Tax 1 2 2 4  
Amortization of Actuarial Loss, Pre-Tax (12) (17) (24) (34)  
Amortization of Actuarial Loss, Tax 5 7 10 14  
Amortization of Actuarial Loss, After-Tax (7) (10) (14) (20)  
Operating Expense [Member] | Power [Member] | Pension and OPEB Plans [Member]          
Reclassification out of Accumulated Other Comprehensive Income [Line Items]          
Amortization of Prior Service (Cost) Credit, Pre-Tax 2 2 4 5  
Amortization of Prior Service (Cost) Credit, Tax (1) (1) (2) (2)  
Amortization of Prior Service (Cost) Credit, After-Tax 1 1 2 3  
Amortization of Actuarial Loss, Pre-Tax (10) (14) (21) (29)  
Amortization of Actuarial Loss, Tax 4 6 9 12  
Amortization of Actuarial Loss, After-Tax (6) (8) (12) (17)  
Other Income [Member] | Available-for-Sale Securities [Member]          
Reclassification out of Accumulated Other Comprehensive Income [Line Items]          
Reclassification for Available for Sale Securities, Pre-Tax 34 12 70 28  
Reclassification for Available for Sale Securities, Tax (17) (6) (34) (14)  
Reclassification for Available for Sale Securities, After-Tax 17 6 36 14  
Other Income [Member] | Power [Member] | Available-for-Sale Securities [Member]          
Reclassification out of Accumulated Other Comprehensive Income [Line Items]          
Reclassification for Available for Sale Securities, Pre-Tax 32 10 57 25  
Reclassification for Available for Sale Securities, Tax (16) (5) (29) (13)  
Reclassification for Available for Sale Securities, After-Tax 16 5 28 12  
Other Expense [Member] | Available-for-Sale Securities [Member]          
Reclassification out of Accumulated Other Comprehensive Income [Line Items]          
Reclassification for Available for Sale Securities, Pre-Tax (6) (7) (13) (24)  
Reclassification for Available for Sale Securities, Tax 4 4 7 12  
Reclassification for Available for Sale Securities, After-Tax (2) (3) (6) (12)  
Other Expense [Member] | Power [Member] | Available-for-Sale Securities [Member]          
Reclassification out of Accumulated Other Comprehensive Income [Line Items]          
Reclassification for Available for Sale Securities, Pre-Tax (5) (6) (10) (22)  
Reclassification for Available for Sale Securities, Tax 3 3 5 11  
Reclassification for Available for Sale Securities, After-Tax (2) (3) (5) (11)  
Other-Than-Temporary Impairments [Member] | Available-for-Sale Securities [Member]          
Reclassification out of Accumulated Other Comprehensive Income [Line Items]          
Reclassification for Available for Sale Securities, Pre-Tax (3) (10) (4) (20)  
Reclassification for Available for Sale Securities, Tax 1 5 2 10  
Reclassification for Available for Sale Securities, After-Tax (2) (5) (2) (10)  
Other-Than-Temporary Impairments [Member] | Power [Member] | Available-for-Sale Securities [Member]          
Reclassification out of Accumulated Other Comprehensive Income [Line Items]          
Reclassification for Available for Sale Securities, Pre-Tax (3) (10) (4) (20)  
Reclassification for Available for Sale Securities, Tax 1 5 2 10  
Reclassification for Available for Sale Securities, After-Tax $ (2) $ (5) $ (2) $ (10)