SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning of period		$ 67,240	$ 67,158	$ 72,468
Costs and expenses		5,747	5,841	4,460
Other accounts		963	314	5,646
Deductions		3,671	4,946	12,857
Currency translation adjustments		(1,515)	(1,127)	(2,559)
End of period		68,764	67,240	67,158
Allowance for Doubtful Accounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning of period		873	1,062	1,139
Costs and expenses		215	135	400
Other accounts		41	0	4
Deductions	[1]	280	271	401
Currency translation adjustments		(53)	(53)	(80)
End of period		796	873	1,062
Inventory Valuation Reserve [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning of period		22,704	21,307	22,032
Costs and expenses		3,612	3,995	3,451
Other accounts		0	314	16
Deductions		2,829	2,521	2,533
Currency translation adjustments		(531)	(391)	(1,659)
End of period		22,956	22,704	21,307
Valuation Allowance of Deferred Tax Assets [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning of period		43,663	44,789	49,297
Costs and expenses		1,920	1,711	609
Other accounts		922	0	5,626
Deductions		562	2,154	9,923
Currency translation adjustments		(931)	(683)	(820)
End of period		$ 45,012	$ 43,663	$ 44,789

[1] (1) Uncollectable accounts written off, net of recoveries.