Schedule II - Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Allowance for Doubtful Accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 5,553		$ 5,300		$ 5,232
Charged (Credited) to Cost and Expense	274		425		954
Effect of Foreign Currency Translation	(579)		(47)		(59)
Deduction from Reserves	(246)		(125)		(827)
Balance at End of Year	5,002		5,553		5,300
Allowance for Sales Returns
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	7,074		5,336		5,746
Charged (Credited) to Cost and Expense	5,453		7,660		3,912
Effect of Foreign Currency Translation	(6,937)		(397)		(155)
Deduction from Reserves	(538)		(5,525)		(4,167)
Balance at End of Year	5,052		7,074		5,336
Allowance for Customer Rebates
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	1,314		1,364		1,265
Charged (Credited) to Cost and Expense	1,009		647		878
Effect of Foreign Currency Translation	(129)		(34)		29
Deduction from Reserves	(599)		(663)		(808)
Balance at End of Year	1,595		1,314		1,364
Income Tax Valuation Account
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	99,859		112,143		105,388
Charged (Credited) to Cost and Expense	7,519		(2,973)		4,324
Effect of Foreign Currency Translation	2,042	[1]	(2,840)	[1]	2,431	[1]
Deduction from Reserves	(6,625)		(6,471)		0
Balance at End of Year	$ 102,795		$ 99,859		$ 112,143

[1] This includes amounts recorded to Accumulated Other Comprehensive Income.