Benefit Plans (Allocation Of Plan Assets) (Details)	12 Months Ended
	Dec. 31, 2012
Pension Plans, Defined Benefit [Member] | Cash and Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Target range allocation, minimum	0.00%
Target range allocation, maximum	5.00%
Actual allocation	4.00%
Pension Plans, Defined Benefit [Member] | U.S. Large Cap Core [Member]
Defined Benefit Plan Disclosure [Line Items]
Target range allocation, minimum	10.00%
Target range allocation, maximum	20.00%
Actual allocation	13.00%
Pension Plans, Defined Benefit [Member] | U.S. Large Cap Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Target range allocation, minimum	6.00%
Target range allocation, maximum	16.00%
Actual allocation	11.00%
Pension Plans, Defined Benefit [Member] | U.S. Large Cap Growth [Member]
Defined Benefit Plan Disclosure [Line Items]
Target range allocation, minimum	6.00%
Target range allocation, maximum	16.00%
Actual allocation	11.00%
Pension Plans, Defined Benefit [Member] | U.S. Small Cap Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Target range allocation, minimum	0.00%
Target range allocation, maximum	6.00%
Actual allocation	3.00%
Pension Plans, Defined Benefit [Member] | U.S. Small Cap Growth [Member]
Defined Benefit Plan Disclosure [Line Items]
Target range allocation, minimum	0.00%
Target range allocation, maximum	6.00%
Actual allocation	3.00%
Pension Plans, Defined Benefit [Member] | International - Developed Markets [Member]
Defined Benefit Plan Disclosure [Line Items]
Target range allocation, minimum	11.00%
Target range allocation, maximum	23.00%
Actual allocation	16.00%
Pension Plans, Defined Benefit [Member] | International - Emerging Markets [Member]
Defined Benefit Plan Disclosure [Line Items]
Target range allocation, minimum	0.00%
Target range allocation, maximum	8.00%
Actual allocation	4.00%
Pension Plans, Defined Benefit [Member] | Global Asset Allocation Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target range allocation, minimum	5.00%
Target range allocation, maximum	15.00%
Actual allocation	10.00%
Pension Plans, Defined Benefit [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target range allocation, minimum	15.00%
Target range allocation, maximum	35.00%
Actual allocation	25.00%
Other Postretirement Benefits Plans [Member] | Cash and Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Target range allocation, minimum	0.00%
Target range allocation, maximum	5.00%
Actual allocation	2.00%
Other Postretirement Benefits Plans [Member] | Domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Target range allocation, minimum	25.00%
Target range allocation, maximum	45.00%
Actual allocation	34.00%
Other Postretirement Benefits Plans [Member] | International [Member]
Defined Benefit Plan Disclosure [Line Items]
Target range allocation, minimum	10.00%
Target range allocation, maximum	20.00%
Actual allocation	15.00%
Other Postretirement Benefits Plans [Member] | Global Asset Allocation Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target range allocation, minimum	20.00%
Target range allocation, maximum	40.00%
Actual allocation	29.00%
Other Postretirement Benefits Plans [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target range allocation, minimum	10.00%
Target range allocation, maximum	30.00%
Actual allocation	20.00%