XML 118 R74.htm IDEA: XBRL DOCUMENT v3.7.0.1
Derivative Financial Instruments - Summary of Economic Hedges (Details) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Derivative [Line Items]    
Unrealized Gain (Loss) on Derivatives $ (47) $ 107
Unrealized Gain (Loss) on Derivatives and Commodity Contracts (49) 103
Exelon Generation Co L L C [Member]    
Derivative [Line Items]    
Unrealized Gain (Loss) on Derivatives (51) 106
Unrealized Gain (Loss) on Derivatives and Commodity Contracts (49) 103
Purchased Power And Fuel [Member] | Exelon Generation Co L L C [Member]    
Derivative [Line Items]    
Unrealized Gain (Loss) on Derivatives and Commodity Contracts (93) 40
Interest Expense [Member] | Exelon Generation Co L L C [Member]    
Derivative [Line Items]    
Unrealized Gain (Loss) on Derivatives (47) 108
Operating Revenue [Member] | Exelon Generation Co L L C [Member]    
Derivative [Line Items]    
Unrealized Gain (Loss) on Derivatives and Commodity Contracts 44 63
Operating Revenue [Member]    
Derivative [Line Items]    
Unrealized Gain (Loss) on Derivatives and Commodity Contracts (2) 3
Foreign Exchange Contract [Member] | Purchased Power And Fuel [Member] | Exelon Generation Co L L C [Member]    
Derivative [Line Items]    
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net 0 0
Unrealized Gain (Loss) on Derivatives 0 0
Change in Unrealized Gain (Loss) on Hedged Item in Foreign Currency Fair Value Hedge 0 0
Foreign Exchange Contract [Member] | Interest Expense [Member]    
Derivative [Line Items]    
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net (1) (2)
Unrealized Gain (Loss) on Derivatives (2) (5)
Change in Unrealized Gain (Loss) on Hedged Item in Foreign Currency Fair Value Hedge (1) (3)
Foreign Exchange Contract [Member] | Interest Expense [Member] | Exelon Generation Co L L C [Member]    
Derivative [Line Items]    
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net (1) (2)
Unrealized Gain (Loss) on Derivatives (2) (5)
Change in Unrealized Gain (Loss) on Hedged Item in Foreign Currency Fair Value Hedge (1) (3)
Foreign Exchange Contract [Member] | Operating Revenue [Member] | Exelon Generation Co L L C [Member]    
Derivative [Line Items]    
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net (1) (2)
Unrealized Gain (Loss) on Derivatives (2) (5)
Change in Unrealized Gain (Loss) on Hedged Item in Foreign Currency Fair Value Hedge (1) (3)
Foreign Exchange Contract [Member] | Operating Revenue [Member]    
Derivative [Line Items]    
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net (1) 1
Unrealized Gain (Loss) on Derivatives (1) (1)
Change in Unrealized Gain (Loss) on Hedged Item in Foreign Currency Fair Value Hedge 0 (2)
Commodity Contract [Member] | Purchased Power And Fuel [Member] | Exelon Generation Co L L C [Member]    
Derivative [Line Items]    
Unrealized Gain (Loss) on Commodity Contracts (135) (127)
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net 42 167
Unrealized Gain (Loss) on Derivatives (93) 40
Commodity Contract [Member] | Interest Expense [Member]    
Derivative [Line Items]    
Unrealized Gain (Loss) on Commodity Contracts (42) 152
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net (5) (44)
Unrealized Gain (Loss) on Derivatives (47) 108
Commodity Contract [Member] | Interest Expense [Member] | Exelon Generation Co L L C [Member]    
Derivative [Line Items]    
Unrealized Gain (Loss) on Commodity Contracts (42) 152
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net (5) (44)
Commodity Contract [Member] | Operating Revenue [Member] | Exelon Generation Co L L C [Member]    
Derivative [Line Items]    
Unrealized Gain (Loss) on Commodity Contracts 93 279
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net (47) (211)
Unrealized Gain (Loss) on Derivatives 46 68
Commodity Contract [Member] | Operating Revenue [Member]    
Derivative [Line Items]    
Unrealized Gain (Loss) on Commodity Contracts 0 7
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net (1) (3)
Unrealized Gain (Loss) on Derivatives $ (1) $ 4