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 [Member]
Movement in Valuation Allowances and Reserves
Balance at beginning of period	$ 5,654		$ 4,080		$ 2,360
Additions - Charged to costs and expenses	1,505		2,447		3,067
Additions - Charged to other accounts	0	[1]	199	[1]	930
Deductions	(633)	[2]	(1,149)	[2]	(2,289)	[2]
Translations	51		(77)		(12)
Balance at end of period	6,475		5,654		4,080
Inventory Valuation Reserve [Member]
Movement in Valuation Allowances and Reserves
Balance at beginning of period	6,556		4,078		3,191
Additions - Charged to costs and expenses	4,087		2,010		2,507
Additions - Charged to other accounts	0		675	[1]	1,085	[1]
Deductions	(5,158)	[3]	(313)	[3]	(2,732)	[3]
Translations	252		(106)		27
Balance at end of period	5,233		6,556		4,078
Valuation Allowance of Deferred Tax Assets [Member]
Movement in Valuation Allowances and Reserves
Balance at beginning of period	1,250		1,766		1,869
Additions - Charged to costs and expenses	1,089		339		1,251
Additions - Charged to other accounts	0		0		0
Deductions	(290)	[4]	(879)	[4]	(1,362)
Translations	67		(24)		(8)
Balance at end of period	$ 1,982		$ 1,250		$ 1,766

[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.

[4] Deductions to the deferred tax assets valuation allowance relate to decreased deferred tax assets and the release of the valuation allowance.