CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income (loss) from continuing operations, net of tax	$ 69,134	$ 44,250	$ 38,551
Foreign currency translation adjustment	6,710	(6,632)	(4,588)
Net unrealized gain (loss) (net of taxes of $1,555 in 2012, $292 in 2011 and $212 in 2010) on marketable securities.	1,168	(110)	1,611
Unrealized gain (loss) on derivative instruments held at year end (net of taxes of $127 in 2012)	(235)	(270)
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	270	0	142
Other comprehensive income (loss)	4,994	(49,255)	(5,121)
Comprehensive income (loss) from continuing operations	74,128	(5,005)	33,430
Income (loss) from discontinued operations, net of income taxes	(449)	(7,195)	(3,980)
Comprehensive income (loss)	73,679	(12,200)	29,450
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax	1,555	292	212
Actuarial net gain (loss) incurred in fisal year [Member]
Pension and other post-employment benefits	(6,687)	(44,964)	(4,413)
Amortization of gain (loss) [Member]
Pension and other post-employment benefits	3,760	2,752	2,153
Amortization of prior service credit (cost) [Member]
Pension and other post-employment benefits	$ 8	$ (31)	$ (26)