Valuation And Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Allowance For Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of year	$ 53	$ 58	$ 207
Additions charged to costs and expenses	367	153	69
Deductions	211	158	218
Balance at end of year	209	53	58
Tax Valuation Allowance [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of year	38,461	54,513	59,603
Deductions	558	16,052	5,090
Balance at end of year	$ 37,903	$ 38,461	$ 54,513