The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount of interest capitalized during the period.

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The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value.

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Property, Plant and Equipment (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Depreciation of property, plant and equipment	$ 14,813	$ 13,648	$ 13,619	$ 14,642	$ 15,984	$ 16,002	$ 15,871	$ 14,652	$ 56,722	$ 62,509	$ 64,620
Interest Costs Capitalized									$ 800	$ 300	$ 400
Graham Healthcare Group [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment impairment charges		$ 200				$ 400
Other Businesses [Member] \| Forney [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment impairment charges							$ 600