Income Taxes (Schedule Of Roll Forward Of Valuation Allowance For Deferred Income Tax Assets) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011	Dec. 31, 2010
Income Taxes [Abstract]
Valuation Allowance, Balance at beginning of period	$ 18,504		$ 21,504	$ 88,868
Charged (Credited) to Costs and Expenses	(1,300)		(3,000)	(67,364)
Other Adjustments	406	[1]
Valuation Allowance, Balance at end of period	$ 17,610		$ 18,504	$ 21,504

[1] Increase in valuation allowance due to the acquisition of certain deferred tax assets where the more likely than not criteria was not met.