SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Allowance for Bad Debts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	$ 268	$ 219
Additions	92	163
Write-offs	(66)	(114)
Ending Balance	294	268
Allowance for Customer Credits [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	158	321
Additions	511	391
Write-offs	(558)	(554)
Ending Balance	111	158
Tax Valuation Allowance [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	43,883	44,457
Charged (credit) to tax expense	(37,527)	(574)
Ending Balance	$ 6,356	$ 43,883