Other Employee Benefit Plans Other Employee Benefit Plans (Details 3) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Change in benefit obligation:
Benefit obligation at January 1	$ 20,564	$ 22,220
Service costs	205	142	125
Interest costs	1,047	1,135	1,085
Actuarial loss (gain)	2,697	1,319
Benefits paid	(436)	(4,541)
Foreign currency exchange changes	(98)	289
Benefit obligation at December 31	23,979	20,564	22,220
Fair value of plan assets at December 31	0	0
Unfunded status at December 31	23,979	20,564
Amounts recognized in the Consolidated Balance Sheets:
Current liabilities	401	420
Non-current liabilities	$ 23,578	$ 20,144
Supplemental Executive Retirement Plan (SERP)
Net periodic benefit cost:
Discount rate	5.15%	5.50%
Rate of increase in compensation levels	5.00%	5.00%
Funded status and projected benefit obligation:
Discount rate	4.00%	5.15%
Rate of increase in compensation levels	5.00%	5.00%
Defined benefit pension plan for employees outside the United States
Net periodic benefit cost:
Discount rate	3.40%	4.70%
Funded status and projected benefit obligation:
Discount rate	3.40%	4.70%