Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Effective Tax Rate	29.70%	26.20%	28.70%
Income tax ruling exemption	$ 8,500	$ 8,500	$ 6,500
Cumulative earnings of non-United States subsidiaries considered to be indefinitely invested outside of United States	493,300
Unrecognized tax benefits	7,204	5,942	6,325	$ 5,906
Unrecognized tax benefits that would impact effective tax rate if recognized	5,900	5,000
Interest expense and penalties related to unrecognized tax benefits	300	300	$ 300
Interest expense and penalties accrued	600	$ 500
Net operating loss carryforwards in certain state and international jurisdictions	31,500
Valuation allowance against certain deferred tax assets related to net operating loss carryforwards	$ 4,400
Tax years no longer subject to U.S. federal examination [Member]
Years before	2013
With few exceptions, tax years no longer subject to state or local and international jurisdicition examination [Member]
Years before	2007
Switzerland [Member]
Expiration date for tax holidays	December 31, 2015
Netherlands [Member]
Expiration date for tax holidays	December 31, 2022