Accumulated Other Comprehensive Loss (Schedule Of Components Of Accumulated Other Comprehensive Loss) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2011
Accumulated Other Comprehensive Loss [Abstract]
Accumulated Other Comprehensive Income (Loss), Derivatives, Net of Tax (Beginning Balance)	$ (6,753)	$ 6,282	$ 18,182	$ (1,306)
Accumulated Other Comprehensive Income (Loss), Unrealized Gains (Losses) on Investments, Net of Tax (Beginning Balance)	1,115	775	117	580
Accumulated Other Comprehensive Income (Loss), Postretirement Benefits, Net of Tax (Beginning Balance)	(82,047)	(64,796)	(65,029)	(132,695)
Accumulated Other Comprehensive Income (Loss), Proportionate Share of Telesat Other Comprehensive Loss, Net of Tax	(8,188)	(5,139)		(21,054)
Accumulated Other Comprehensive Income (Loss), Accumulated Other Comprehensive Loss, Net of Tax	(95,873)	(62,878)	(46,730)	(154,475)
Derivative - Period Change	5,447	(13,035)	(11,900)
Unrealized Gains(Losses) on Investments - Period Change	(535)	340	658
Postretirement Benefits - Period Change	(50,648)	(17,251)	233
Accumulated Other Comprehensive Income (Loss), Proportionate Share of Telesat Other Comprehensive Loss Period Change, Net of Tax	(12,866)	(3,049)	(5,139)
Accumulated Other Comprehensive Income (Loss), Other Comprehensive Loss Period Change, Net of Tax	$ (58,602)	$ (32,995)	$ (16,148)