Accounts Receivable (Schedule Of Allowance For Doubtful Accounts) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance Beginning of Year				$ 69
Balance at End of Year		467	403	69
Allowance for Doubtful Accounts [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance Beginning of Year	467	403
Additions Charged to Costs and Expenses	259	247	539
Recoveries (Deductions)	41	(183)	(205)
Balance at End of Year	$ 767	$ 467	$ 403