Benefit Plans (Estimated Net Loss and Prior Service Cost (Credit) Expected to be Amortized in 2016) (Details) $ in Millions |
12 Months Ended |
---|---|
Dec. 31, 2015
USD ($)
| |
Postretirement Benefit Plan [Member] | |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |
Estimated future net loss | $ 30 |
Estimate future prior service cost (credit) | (40) |
Pension [Member] | |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |
Estimated future net loss | 183 |
Estimate future prior service cost (credit) | $ 5 |