Employee Benefits (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012 item	Dec. 31, 2010
Employee Benefits
Number of Swiss plans that require employee contributions	1
Number of foreign plans for which accrual of benefits was frozen			1
Number of foreign plans for which significant lump sum payments were made	2
Settlement charge recognized as a result of significant lump sum payments	$ 200,000
Amortization of prior service cost		3,200,000
Number of foreign pension plans that changed the interest rates used to convert lump sums to annuity payments		2
401(k) defined contribution plan
Retirement benefits under the defined contribution plan
Eligible service period for employer's contribution	1 year
Employer's contribution (as a percent)	4.00%
Employer's matching contribution percentage of employee's contribution percentage	25.00%
Employer's contribution	1,600,000	1,400,000
Age to be reached by employees to be eligible for enhanced participation	50 years
Minimum age of employees as of January 1, 2011 to be eligible for enhanced employer contributions	40 years
Expense recognized on permanent freeze of benefit accruals under the domestic defined benefit plan	1,800,000	1,600,000
Employer's matching contribution of employee's additional contribution	$ 0
Retiree health plan
Retirement benefits under the defined contribution plan
Eligible service period for participating in the plan	10 years
Eligible age to elect early retirement	55 years
Eligible service period for participating in the plan on electing early retirement	15 years