Discontinued Operations And Other Disposition (Schedule Of Disposal Groups Including Discontinued Operations) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Discontinued Operations And Other Disposition [Abstract]
Property, plant and equipment, at cost	$ 46,933	$ 128,463
Less: accumulated depreciation	19,891	48,856
Net property, plant and equipment	27,042	79,607
Current assets	1,429	4,656
Regulatory assets	136	2,034
Other assets		126
Assets of discontinued operations held for sale	28,607	86,423
Current liabilities	6,574	2,074
Deferred income taxes and investment tax credits	2,443	5,166
Contributions in aid of construction	7,506	15,560
Other liabilities	829	837
Liabilities of discontinued operations held for sale	17,352	23,637
Net assets	$ 11,255	$ 62,786