Schedule II - Valuation and Qualifying Accounts - Schedule of Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for doubtful trade receivables [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 7,739	$ 6,241	$ 2,364
Charges to costs and expenses	1,259	5,741	4,832
Recoveries and write offs	(3,428)	(4,243)	(955)
Balance at end of period	5,570	7,739	6,241
Allowance for excess and slow moving inventory [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	39,247	34,607	33,216
Charges to costs and expenses	5,748	8,512	3,951
Recoveries and write offs	653	(3,872)	(2,560)
Balance at end of period	$ 45,648	$ 39,247	$ 34,607