CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$ 94,732	$ 132,189	$ 68,254
Other comprehensive income, net of tax:
Currency translation gain	20,577	2,776	9,328
Unrealized gain (loss) on securities	2,251	(322)	325
Defined benefit pension plan:
Actuarial gain (loss)	690	1,966	(4,068)
Prior service cost	(77)	(75)	(27)
Curtailment gain	457	0	0
Total other comprehensive income, net of tax	23,898	4,345	5,558
Comprehensive income	$ 118,630	$ 136,534	$ 73,812