Summary of Significant Accounting Policies (Restructuring Costs) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) Facility Employees
Restructuring Cost and Reserve [Line Items]
Severance expense	$ 300
Restructuring Reserve [Roll Forward]
Restructuring accrual beginning balance	1,029
Provision	(69)
Cash payments	(960)
Restructuring accrual ending balance	0
Severance
Restructuring Reserve [Roll Forward]
Restructuring accrual beginning balance	654
Provision	(75)
Cash payments	(579)
Restructuring accrual ending balance	0
Other
Restructuring Reserve [Roll Forward]
Restructuring accrual beginning balance	375	[1]
Provision	6	[1]
Cash payments	(381)	[1]
Restructuring accrual ending balance	0	[1]
Distribution
Restructuring Cost and Reserve [Line Items]
Severance expense	700
Aerospace
Restructuring Cost and Reserve [Line Items]
Severance expense	$ 2,500
Distributions segment
Restructuring Cost and Reserve [Line Items]
Restructuring, number of positions eliminated (in employees) | Employees	60
Restructuring, number of facilities eliminated | Facility	4

[1] (a) Includes costs associated with consolidation of facilities