Schedule II - Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Allowance for doubtful accounts [Member]
Movement in Valuation Allowances and Reserves
Balance at beginning of period	$ 3,008		$ 1,727		$ 2,312
Additions - Charged to costs and expenses	4,205		3,326		2,386
Additions - Charged to other accounts	52	[1]	489	[1]	0
Deductions	(4,919)	[2]	(2,552)	[2]	(3,007)	[2]
Translations	14		18		36
Balance at end of period	2,360		3,008		1,727
Allowance for obsolete and excess inventory [Member]
Movement in Valuation Allowances and Reserves
Balance at beginning of period	3,181		4,184		1,912
Additions - Charged to costs and expenses	3,331		1,800		4,450
Additions - Charged to other accounts	0		201	[1]	910	[1]
Deductions	(3,398)	[3]	(2,965)	[3]	(3,148)	[3]
Translations	77		(39)		60
Balance at end of period	$ 3,191		$ 3,181		$ 4,184

[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.