Retirement Plans (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014 contract	Jun. 30, 2013
Defined Benefit Plan Disclosure [Line Items]
Number of retirement plans			5
Defined Benefit Plan Number			3
Active Defined Benefit Plan Number			1
Inactive Defined Benefit Plan Number			2
Defined Contribution Plan Number			2
Defined Contribution Plan, Cost Recognized	$ 631	$ 608	$ 1,306	$ 1,184
Salaried Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Contribution Plan, Cost Recognized	523	495	1,079	944
Union Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Contribution Plan, Cost Recognized	22	19	39	35
Canadian Employees [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Contribution Plan Number			2
United Kingdom Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plans, Estimated Future Employer Contributions in Current Fiscal Year			298
Defined Benefit Plan, Contributions by Employer			154
Defined Contribution Plan, Cost Recognized	30	35	68	68
Kelsan Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Description of Postemployment Benefits			The Company sponsors five defined contribution plans for hourly and salaried employees across our domestic and international facilities. The following table summarizes the expense associated with the contributions made to these plans.
United States Pension Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plans, Estimated Future Employer Contributions in Current Fiscal Year			448
Defined Benefit Plan, Contributions by Employer			$ 149