Restructuring Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restructuring Reserve [Roll Forward]
Restructuring accrual balance at December 31, 2016	$ 0
Provision	1,547
Cash payments	(202)
Changes in foreign currency exchange rates	6
Restructuring accrual balance at December 31, 2017	1,351	$ 0
Restructuring costs	2,661	1,032	$ 1,496
Inventory Write-down	1,000
Effect on Future Earnings, Amount	4,000
Employee Severance
Restructuring Reserve [Roll Forward]
Restructuring accrual balance at December 31, 2016	0
Provision	1,369
Cash payments	(202)
Changes in foreign currency exchange rates	5
Restructuring accrual balance at December 31, 2017	1,172	0
Other Restructuring
Restructuring Reserve [Roll Forward]
Restructuring accrual balance at December 31, 2016	0
Provision	178
Cash payments	0
Changes in foreign currency exchange rates	1
Restructuring accrual balance at December 31, 2017	179	0
Voluntary Retirement Program
Restructuring Reserve [Roll Forward]
Severance Costs		300
Distribution
Restructuring Reserve [Roll Forward]
Severance Costs	500	700
Aerospace
Restructuring Reserve [Roll Forward]
Severance Costs	400	$ 2,500
Corporate, Non-Segment
Restructuring Reserve [Roll Forward]
Severance Costs	2,800
Minimum
Restructuring Reserve [Roll Forward]
Expected restructuring costs	7,000
Maximum
Restructuring Reserve [Roll Forward]
Expected restructuring costs	$ 8,500