Retirement Plans (Fair Value Of Our Other Post-Retirement Plan Assets by Category and the Corresponding Level within the Fair Value Hierarchy) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Equity Funds
Total other post-retirement plan assets	$ 296
Equity Funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Total other post-retirement plan assets	5
Equity Funds | Significant Other Observable Inputs (Level 2)
Total other post-retirement plan assets	291
Equity Funds | Significant Unobservable Inputs (Level 3)
Total other post-retirement plan assets	0
Fixed Income Funds
Total other post-retirement plan assets	6
Fixed Income Funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Total other post-retirement plan assets	6
Fixed Income Funds | Significant Other Observable Inputs (Level 2)
Total other post-retirement plan assets	0
Fixed Income Funds | Significant Unobservable Inputs (Level 3)
Total other post-retirement plan assets	0
Hedge Funds
Total other post-retirement plan assets	2	1
Hedge Funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Total other post-retirement plan assets	0	0
Hedge Funds | Significant Other Observable Inputs (Level 2)
Total other post-retirement plan assets	1	1
Hedge Funds | Significant Unobservable Inputs (Level 3)
Total other post-retirement plan assets	1	0
Equity Securities
Total other post-retirement plan assets	154	120
Equity Securities | Quoted Prices in Active Markets for Identical Assets (Level 1)
Total other post-retirement plan assets	154	120
Equity Securities | Significant Other Observable Inputs (Level 2)
Total other post-retirement plan assets	0	0
Equity Securities | Significant Unobservable Inputs (Level 3)
Total other post-retirement plan assets	0	0
Fixed Income Securities
Total other post-retirement plan assets	55	56
Fixed Income Securities | Quoted Prices in Active Markets for Identical Assets (Level 1)
Total other post-retirement plan assets	2	1
Fixed Income Securities | Significant Other Observable Inputs (Level 2)
Total other post-retirement plan assets	53	55
Fixed Income Securities | Significant Unobservable Inputs (Level 3)
Total other post-retirement plan assets	0	0
Commingled Funds | Equity Funds
Total other post-retirement plan assets		225
Commingled Funds | Equity Funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Total other post-retirement plan assets		4
Commingled Funds | Equity Funds | Significant Other Observable Inputs (Level 2)
Total other post-retirement plan assets		221
Commingled Funds | Equity Funds | Significant Unobservable Inputs (Level 3)
Total other post-retirement plan assets		0
Commingled Funds | Fixed Income Funds
Total other post-retirement plan assets		6
Commingled Funds | Fixed Income Funds | Quoted Prices in Active Markets for Identical Assets (Level 1)
Total other post-retirement plan assets		6
Commingled Funds | Fixed Income Funds | Significant Other Observable Inputs (Level 2)
Total other post-retirement plan assets		0
Commingled Funds | Fixed Income Funds | Significant Unobservable Inputs (Level 3)
Total other post-retirement plan assets		0
Other Postretirement Benefit Plans, Defined Benefit
Total other post-retirement plan assets	519	426
Other Postretirement Benefit Plans, Defined Benefit | Quoted Prices in Active Markets for Identical Assets (Level 1)
Total other post-retirement plan assets	173	149
Other Postretirement Benefit Plans, Defined Benefit | Significant Other Observable Inputs (Level 2)
Total other post-retirement plan assets	345	277
Other Postretirement Benefit Plans, Defined Benefit | Significant Unobservable Inputs (Level 3)
Total other post-retirement plan assets	1	0
Cash
Total other post-retirement plan assets	6	18
Cash | Quoted Prices in Active Markets for Identical Assets (Level 1)
Total other post-retirement plan assets	6	18
Cash | Significant Other Observable Inputs (Level 2)
Total other post-retirement plan assets	0	0
Cash | Significant Unobservable Inputs (Level 3)
Total other post-retirement plan assets	$ 0	$ 0