Fixed Assets (Schedule of Fixed Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment
Fixed assets, at cost	$ 337,362	$ 291,776
Less accumulated depreciation and amortization	164,614	141,176
Fixed assets, net	172,748	150,600
Land
Property, Plant and Equipment
Fixed assets, at cost	13,802	11,064
Buildings and Improvements
Property, Plant and Equipment
Fixed assets, at cost	106,831	89,616
Leasehold Improvements
Property, Plant and Equipment
Fixed assets, at cost	11,918	11,147
Machinery and Equipment
Property, Plant and Equipment
Fixed assets, at cost	167,691	153,784
Furniture and Fixtures
Property, Plant and Equipment
Fixed assets, at cost	27,053	20,653
Construction in Progress
Property, Plant and Equipment
Fixed assets, at cost	$ 10,067	$ 5,512
Minimum | Buildings and Improvements
Property, Plant and Equipment
Estimated useful life in years	10 years
Minimum | Leasehold Improvements
Property, Plant and Equipment
Estimated useful life in years	3 years
Minimum | Machinery and Equipment
Property, Plant and Equipment
Estimated useful life in years	3 years
Minimum | Furniture and Fixtures
Property, Plant and Equipment
Estimated useful life in years	3 years
Maximum | Buildings and Improvements
Property, Plant and Equipment
Estimated useful life in years	40 years
Maximum | Leasehold Improvements
Property, Plant and Equipment
Estimated useful life in years	10 years
Maximum | Machinery and Equipment
Property, Plant and Equipment
Estimated useful life in years	15 years
Maximum | Furniture and Fixtures
Property, Plant and Equipment
Estimated useful life in years	8 years