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	Dec. 31, 2009
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation Allowances and Reserves, Balance	$ 1,058	$ 1,088	$ 1,061	$ 472
Valuation Allowances And Reserves, Adjustments to Beginning Balance		187	0	0
Valuation Allowances and Reserves, Charged to Cost and Expense	315	660	648
Valuation Allowances and Reserves, Deductions	$ 532	$ 633	$ 59