Cash Equivalents And Restricted Cash And Securities (Summary Of Cash Equivalents And Marketable Securities) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
	Jun. 30, 2013	Dec. 31, 2012
Money Market Funds [Member] | Cash Equivalents [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Cost Basis	$ 722	$ 1,319
Unrealized Holding Gains
Estimated Market Value	722	1,319
Money Market Funds [Member] | Restricted Cash And Securities [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Cost Basis	308	323
Unrealized Holding Gains
Estimated Market Value	308	323
Cash [Member] | Restricted Cash And Securities [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Cost Basis	5,000	5,000
Unrealized Holding Gains
Estimated Market Value	$ 5,000	$ 5,000