Schedule of Valuation and Qualifying Accounts (Tables) (Details) (Allowance for doubtful accounts [Member], USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Allowance for doubtful accounts [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	$ 1,442	$ 1,094	$ 586
Charges to Operatons	67	407	546
Other additions		13	(23)
Deductions	1,171	72	15
Balance at end of period	$ 338	$ 1,442	$ 1,094