Schedule II Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Allowance for doubtful accounts
Valuation and Qualifying Accounts
Balance at Beginning of Year	$ 1,362	$ 1,200	$ 1,743
Additions Charged to Costs and Expenses	488	464	215
Deductions Returns and Write-Offs	(522)	(302)	(758)
Balance at End of Year	1,328	1,362	1,200
Income tax valuation allowance
Valuation and Qualifying Accounts
Balance at Beginning of Year	1,146
Additions Charged to Costs and Expenses	988	1,146
Deductions Returns and Write-Offs	(1,146)
Balance at End of Year	$ 988	$ 1,146