SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Allowance for Bad Debts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	$ 490	$ 294	$ 268
Additions	379	354	92
Write-offs	(264)	(158)	(66)
Ending Balance	605	490	294
Allowance for Customer Credits [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	280	111	158
Additions	803	1,037	511
Write-offs	(644)	(868)	(558)
Ending Balance	439	280	111
Tax Valuation Allowance [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	6,015	6,356	43,883
Charged (credit) to tax expense	(588)	(341)	(37,527)
Ending Balance	$ 5,427	$ 6,015	$ 6,356