Schedule II - Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Allowance for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves
Balance at beginning of period	$ 2,360		$ 3,008		$ 1,727
Additions - Charged to costs and expenses	3,067		4,205		3,326
Additions - Charged to other accounts	930	[1]	52	[1]	489
Deductions	(2,289)	[2]	(4,919)	[2]	(2,552)	[2]
Translations	(12)		(14)		(18)
Balance at end of period	4,080		2,360		3,008
Inventory Valuation Reserve [Member]
Movement in Valuation Allowances and Reserves
Balance at beginning of period	3,191		3,181		4,184
Additions - Charged to costs and expenses	2,507		3,331		1,800
Additions - Charged to other accounts	1,085		0	[1]	201	[1]
Deductions	(2,732)	[3]	(3,398)	[3]	(2,965)	[3]
Translations	(27)		(77)		(39)
Balance at end of period	$ 4,078		$ 3,191		$ 3,181

[1] Reserves at date of acquisition of subsidiary or subsidiaries.

[2] Reversal of amounts previously recorded as bad debt and uncollectible accounts written off.

[3] Inventory items written off against the allowance.