SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for doubtful accounts and sales returns and allowances
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 5,572	$ 5,659	$ 5,126
Charged to Costs and Expenses	2,009	1,262	2,211
Deductions	(1,262)	(1,349)	(1,678)
Balance at End of Period	6,319	5,572	5,659
Deferred tax assets valuation allowance
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	4,887	6,772	7,283
Charged to Costs and Expenses	(1,228)	80	3
Deductions	(55)	(1,965)	(514)
Balance at End of Period	$ 3,604	$ 4,887	$ 6,772