v3.3.1.900
Commitments and Contingencies (Narrative) (Details)
$ in Millions
12 Months Ended
Dec. 31, 2015
USD ($)
Dec. 31, 2014
USD ($)
Dec. 31, 2013
USD ($)
Commitments and Contingencies [Line Items]      
Royalty Expense $ 23 $ 28 $ 27
Guarantor Obligations, Current Carrying Value $ 0    
Outstanding claims related to guarantees 0    
LTSA [Member]      
Unrecorded Unconditional Purchase Obligation      
Unrecorded Unconditional Purchase Obligation $ 183    
Term of Unrecorded Unconditional Purchase Obligation Lower Limit 1 year    
Term of Unrecorded Unconditional Purchase Obligation Upper Limit 10 years    
Electric Generation Equipment [Member]      
Commitments and Contingencies [Line Items]      
Operating Leases, Rent Expense, Net $ 43 46 47
Office Equipment [Member]      
Commitments and Contingencies [Line Items]      
Operating Leases, Rent Expense, Net 11 $ 11 $ 12
Operating Leases, Future Minimum Payments Due, Next Twelve Months 13    
Unrecorded Unconditional Purchase Obligation      
Operating Leases, Future Minimum Payments, Due in Two Years 13    
Operating Leases, Future Minimum Payments, Due in Three Years 13    
Operating Leases, Future Minimum Payments, Due in Four Years 12    
Operating Leases, Future Minimum Payments, Due in Five Years 10    
Operating Leases, Future Minimum Payments, Due Thereafter 0    
Operating Leases, Future Minimum Payments Due $ 61