Commitments And Contingent Liabilities (Minimum Fuel Purchase Requirements) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2011
Total minimum purchase requirements	$ 1,032
Power [Member] | Commitments Through 2015 [Member] | Nuclear Fuel Uranium [Member]
Total minimum purchase requirements	491
Power [Member] | Commitments Through 2015 [Member] | Nuclear Fuel Enrichment [Member]
Total minimum purchase requirements	457
Power [Member] | Commitments Through 2015 [Member] | Nuclear Fuel Fabrication [Member]
Total minimum purchase requirements	129
Power [Member] | Commitments Through 2015 [Member] | Natural Gas [Member]
Total minimum purchase requirements	959
Power [Member] | Commitments Through 2015 [Member] | Coal/Oil [Member]
Total minimum purchase requirements	1,032
Power [Member]
Coverage percentage of nuclear fuel commitments of uranium, enrichment, and fabrication requirements	100.00%
Amount of coal / oil commitments Power can cancel at no cost	$ 687