Schedule II-Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Accounts Receivable Allowance for Doubtful Accounts
Movement in valuation and qualifying accounts
Beginning Balance	$ 225	$ 255	$ 1,215
Additions/Charged to Expenses	486	379	111
Reductions	(593)	(409)	(1,071)
Balance at End of Period	118	225	255
Tax Valuation Allowance
Movement in valuation and qualifying accounts
Additions/Charged to Expenses	491
Balance at End of Period	$ 491